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Early life gut microbiota profiles linked to synbiotic formula effects: a randomized clinical trial in European infants.
Lagkouvardos, I, Intze, E, Schaubeck, M, Rooney, JP, Hecht, C, Piloquet, H, Clavel, T
The American journal of clinical nutrition. 2023;117(2):326-339
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Plain language summary
Microbial colonisation of the intestine after birth is a central event that influences infant health with life-long consequences. Although improvement of hygienic conditions reduces infant mortality due to infections, environments with low microbial biomass counteract natural colonisation by commensal microbes. The aim of this study was to assess the effects of a synbiotic intervention formula (IF) on faecal microbiota. This study was a multicentre, randomised, controlled, double-blind intervention trial which enrolled 540 infants. Infants whose parents had chosen not to breastfeed or were not able to breastfeed prior to study inclusion were allocated randomly to 1 of 2 formula groups (n = 230 control formula, n = 230 IF). The infants in the breastfed reference group (n = 80) were mainly fed human milk. Results showed that synbiotic intervention influenced the gut microbiota and milieu parameters during early life to resemble some major characteristics found in breastfed infants (higher relative abundances of bifidobacteria, lower richness, lower faecal pH and butyrate concentrations), and effects depended on the ecosystem profile of the infants. Authors conclude that specific randomised, controlled studies that focus on infants born by Caesarean section and how early nutrition can support the beneficial development of their microbiota are needed.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Infant gut colonisation differs in vaginal versus cesarean section deliveries and between breastfed and infant formula practices.
- Both enriched strain-specific probiotic and standard infant formula were shown to have a marked effect on microbiota colonisation in infants at age 4 months.
- By the age of 2 years, however, there is no significant difference between breastfed and formula fed infants.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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X
B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
This randomised controlled intervention study compared gut health parameters with the use of a synbiotic pre- and probiotic strain enriched infant formula with human milk and standard formula at three intervals over a period of 2 years.
Methods
This was a double-blinded controlled study of 540 infants from France and Belgium. Participants were randomly allocated to 2 formula groups (n = 230 Control Formula (CF), n = 230 Intervention Formula (IF)) and the breastfed reference group (n = 80) as well as delivery mode (Cesarean and vaginal delivery). The synbiotic IF was a standard infant formula enriched with prebiotic GOS (0.02 g/g) and the probiotic strain L. fermentum CECT5716 (at least 1.0 × 106 cfu/g).
Stool analysis was conducted at three time intervals, 4, 12, and 24 months (infant age). Biomarkers included short chain fatty acids, pH, secretory IgA, calprotectin, and various bacterial phyla via microbiota analysis.
Results
- At 4 months, the IF group tested higher for Bifidobacterium spp., and Lactobacillaceae and lower occurrence of Blautia spp., as well as Ruminoccocus gnavus and relatives compared to CF. They also had lower fecal pH and butyrate levels
- Both the formula cohorts had lower SigA and more basic pH values than the human milk cohort, as well as higher prevalence of anaerobes belonging to the bacterial genera Akkermansia, Collinsella, and Faecalibacterium.
- By age 24 months, the IF cohort exhibited increased levels of Akkermansia, Escherichia-Shigella, and R.gnavus. However there were no significant differences between the formula fed and human milk cohort at this time interval.
- The differences observed at 4 months disappeared over time, except for a significantly higher relative abundance of bifidobacteria and Faecalibacterium spp. in IF infants at 12 months compared with CF infants.
Conclusion:
Although prominent differences between the cohorts were observed at 4 months, it appears that by the age of 2 years, there is little observable difference. This is most likely due to gut ecosystem maturation. The paper draws attention to the fact that changes to microbiota following treatment were more pronounced in infants who tested lower in occurrences of Bacteroides spp at age 4 months. Of note is the prevalence of cesarean birth deliveries in this cohort thereby indicating potential improved alternative feeding options when breastfeeding is not possible for these infants.
Clinical practice applications:
- Probiotic L.fermentum and prebiotic galacto-oligosaccharide enriched infant formula appears to the improve infant microbiome, when compared to that of breastfed infants.
- The most receptive infants were those born via cesarean section.
Limitations to consider:
- The sample groups were from France and Belgium, with no indication as to culture, socio-economic, or sex distribution.
- The two infant formula groups were n=230 each with only 80 infants in the breastfed reference group.
- There was no indication of maternal diet practices pre-, during, and post- pregnancy.
- Stool samples were not collected from the infants at baseline visit prior to formula intervention.
Considerations for future research:
- Future studies need to include more diverse cultural and socio-economic cohorts to ascertain the potential influence of parental diet in baseline infant microbiome.
- It is imperative to establish what role solid food choices, generally introduced at 6 months, might have on gut ecosystem maturation.
- It would be useful to have a larger cesarean section birth cohort to compare to vaginal deliveries for more definitive results.
Abstract
BACKGROUND Microbial colonization of the gastrointestinal tract after birth is an essential event that influences infant health with life-long consequences. Therefore, it is important to investigate strategies to positively modulate colonization in early life. OBJECTIVES This randomized, controlled intervention study included 540 infants to investigate the effects of a synbiotic intervention formula (IF) containing Limosilactobacillus fermentum CECT5716 and galacto-oligosaccharides on the fecal microbiome. METHODS The fecal microbiota from infants was analyzed by 16S rRNA amplicon sequencing at 4, 12, and 24 months of age. Metabolites (e.g., short-chain fatty acids) and other milieu parameters (e.g., pH, humidity, and IgA) were also measured in stool samples. RESULTS Microbiota profiles changed with age, with major differences in diversity and composition. Significant effects of the synbiotic IF compared with control formula (CF) were visible at month 4, including higher occurrence of Bifidobacterium spp. and Lactobacillaceae and lower occurrence of Blautia spp., as well as Ruminoccocus gnavus and relatives. This was accompanied by lower fecal pH and concentrations of butyrate. After de novo clustering at 4 months of age, overall phylogenetic profiles of the infants receiving IF were closer to reference profiles of those fed with human milk than infants fed CF. The changes owing to IF were associated with fecal microbiota states characterized by lower occurrence of Bacteroides compared with higher levels of Firmicutes (valid name Bacillota), Proteobacteria (valid name Pseudomonadota), and Bifidobacterium at 4 months of age. These microbiota states were linked to higher prevalence of infants born by Cesarean section. CONCLUSIONS The synbiotic intervention influenced fecal microbiota and milieu parameters at an early age depending on the overall microbiota profiles of the infants, sharing a few similarities with breastfed infants. This trial was registered at clinicaltrials.gov as NCT02221687.
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Efficacy of diet restriction with or without probiotic for treatment of patients with IBS-D: Phase I-II clinical trial.
Zhao, XS, Shi, LJ, Ning, BL, Zhao, ZM, Li, XX, Zhu, MH, Zhang, YB, Fu, J
Immunity, inflammation and disease. 2023;11(5):e857
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Irritable bowel syndrome (IBS) is a functional intestinal disorder that can significantly affect quality of life. IBS patients suffer from intermittent abdominal pain/ discomfort, altered bowel habits, and abdominal bloating/distension. The aim of this study was to assess the effects of dietary restriction and probiotic use on IBS‐D patients. This study was a 2 × 2 factorial design, single‐centre, randomised trial. Phase 1 was a 12‐week dietary intervention, with 214 participants randomised to an IgG positive restricted diet (IgG res diet) or a control diet (cold/spicy/fried restricted). In Phase 2, 167 participants were randomised into either an IgG res diet + placebo or an IgG res diet + probiotic for 12 weeks. Symptom Severity Scale (IBS‐D‐SSS) and IgG titer were assessed at the beginning and the end of the study. Results showed that both diets reduced IBS‐D symptom severity scores and decreased immunoglobulin (IgG) antibody titer, although the IgG res diet had a greater impact. IBS symptom scores decreased with the addition of a Bifidobacterium probiotic along with dietary exclusion, however, IgG titers did not change with the probiotic compared to placebo. Authors concluded that diet restriction with appropriate and effective probiotics, provides greater symptom reductions for patients with IBS-D.
Expert Review
Conflicts of interest:
None
Take Home Message:
For individuals with IBDS-D:
- Establish IgG intolerances to foods and ensure an elimination diet remains nutritionally balanced
- Consider combining elimination diet with a Bifidobacterium supplement.
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
Irritable bowel syndrome (IBS) is a common functional intestinal disorder, affecting 5-20% of the population and diet is likely a major factor in its development as well as in its management. The aim of this study was to compare 3 dietary interventions and the use of a probiotic supplement in patients with IBS-diarrhoea dominant (IBS-D).
Methods
The study was conducted in 2 phases. The first was a 12-week 2 × 2 factorial design, randomised dietary intervention and included 224 patients (214 completed) with IBS-D. The diets were an Eastern/Chinese restriction diet, avoiding cold/raw, spicy and fried foods (CSF), the second avoided common allergens as determined by an IgG test (IgG diet, 14 foods tested), the third a combination of the two, whilst the control group continued their usual (Eastern/Chinese) diet.
The second phase was a 12-week randomised, double-blind, placebo-controlled trial comparing the CSF + IgG diet plus placebo with the CSF + IgG diet plus a 2 billion Bifidobacterium adolescentis supplement; this part included 202 patients of whom 169 completed the study.
The primary outcomes under observation were a reduction in IBS-D symptom severity Score (IBS-D-SSS) and IgG antibody titre (TigG).
Results
Phase 1: The IBS-D-SSS improved in all four groups from baseline (p<0.001), with the intervention groups improving significantly more than the control group (p<0.001). There was no statistically significant difference between the IgG and the IgG + CSF groups, although the authors considered there to be a synergistic effect. Statistically significant (p<0.001) reductions in TIgG were seen in all interventions, but not the control group.
Part 2: Significant (p<0.001) improvements in IBS-D-SSS were seen with both placebo and Bifidobacterium, although this was greater in the probiotic group (p<0.001). Improvements in TIgG were seen in both groups (p<0.001), with no difference between groups.
Conclusion
The authors concluded that the best intervention for patients with IBD-D is an IgG food elimination diet together with a Bifidobacterium probiotic supplement.
Clinical practice applications:
- Consider an elimination diet based on IgG testing for clients with IBS-D
- Consider combining elimination diet with a Bifidobacterium supplement. The dose used in this study was 4x 0.5 billion capsules of Bifidobacterium adolescentis
- Eliminating cold/raw, spicy and fried food could be an alternative to IgG elimination if the latter is not suitable for the client.
Considerations for future research:
- 45% and 35% of screened patients, respectively in the 2 phases of the study, were IgG negative. Screening for more potential food intolerances may extend the suitability of the approach to more patients
- Only a single strain probiotic was tested. Further research could evaluate other or combinations of Bifidobacteria strains in combination with an IgG elimination diet
- The mechanism(s) by which probiotics may affect symptoms of IBS-D are unknown. Adding stool microbiome analyses may shed further light on the effect of the intervention on the composition and function of the microbiome.
Abstract
BACKGROUND AND AIM Diet is a major contributor to irritable bowel syndrome (IBS) and is also a powerful tool for treatment of IBS. This study compared two diets and explored the effectiveness of the diets when combined with a probiotic for treatment of IBS-D patients. METHODS Phase I, patients were randomized into groups; control, cold/spicy/fried restricted diet (CSF res diet), IgG positive restricted diet (IgG res diet), and a combination both diets (CSF + IgG res diet). Phase II, patients were randomized into IgG res diet + placebo and IgG res diet + probiotic. Both interventions were 12 weeks in duration. Symptom Severity Scale (IBS-D-SSS) and IgG titer were assessed at the beginning and the end of the study. RESULTS Totals of 214 and 167 patients completed the two parts of the study, respectively. After intervention, IBS-D-SSS and TIgG grade were significantly improved compared to baseline, with results similar to the control group. In general, there were decreases in IBS-D-SSS and TIgG grade that were significantly different among the groups. There were exceptions; no differences were observed for IBS-D-SSS between the IgG res diet and CSF + IgG res diet, or TIgG grade between the CSF res diet, IgG res diet, and CSF + IgG res diet. However, the CSF res diet and IgG res diet had a synergistic effect that decreased IBS-D-SSS and TIgG titer, with a greater contribution by the IgG res diet. Therefore, we evaluated the IgG res diet with either placebo or probiotic and found that IBS-D-SSS and TIgG grade decreased from baseline. There was a significant decrease in IBS-D-SSS with the probiotic but TIgG grade was not significantly different between the IgG diet + placebo and IgG diet + probiotic diet. CONCLUSIONS Both the CSF res diet and IgG res diet improved IBS symptoms and demonstrated synergy, although the IgG res diet had a greater contribution. Further, when intolerant foods cannot be eliminated from a diet, avoiding uncooked, cold, spicy, fried, and alcoholic foods is a superior choice. The IgG res diet combined with Bifidobacteria was the best dietary choice and may function though a non-IgG pathway.
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Effect of the probiotic strain, Lactiplantibacillus plantarum P9, on chronic constipation: A randomized, double-blind, placebo-controlled study.
Ma, T, Yang, N, Xie, Y, Li, Y, Xiao, Q, Li, Q, Jin, H, Zheng, L, Sun, Z, Zuo, K, et al
Pharmacological research. 2023;191:106755
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Chronic constipation (CC) is a common gastroenterological problem encountered in clinical practice, and it negatively impacts patients’ quality of life. Growing evidence indicates that the occurrence of CC is closely linked to gut dysbiosis. Several main probiotics have been used to relieve constipation. The main aim of this study was to systematically evaluate the beneficial effects of Lactiplantibacillus plantarum P9 (P9) administration on alleviating CC and impact on the host gut microbiota and its metabolites. This study was a 42-day longitudinal double-blind randomised controlled trial which enrolled a total of 181 patients with CC. Subjects were randomly assigned to the probiotic or placebo group. Subjects in P9 group received one sachet of P9 powder per day after meal. Results show that P9 administration significantly improved patients’ defecation frequency. In fact, P9 administration effectively alleviated constipation, and the symptom relief effects were linked to desired changes and interactions with different types of host microbes. Authors conclude that administering P9 could effectively relieve chronic constipation in adults and improve some aspects of their quality of life.
Expert Review
Conflicts of interest:
None
Take Home Message:
- This study suggested that P9-associated constipation symptom relief was not attributed to macroscopic changes in the host gut bacteriome and phageome
- However, results supported that taking P9 could alleviate constipation, with the symptom relief effects linked to desired changes and interactions with different types of host microbes, including the gut commensal bacteria (L. plantarum, Ruminococcus_B gnavus, Oscillospiraceae sp., Lachnospiraceae sp.) and the bacteriophage family, Herelleviridae.
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
This study investigated the effect of a specific probiotic strain in alleviating Chronic Constipation (CC).
Methods
- The study employed a 42-day randomised control trial (RTC) double-blind, placebo-controlled design, with 163 patients, (mean age =22.68 ±5.66 years for the probiotic group and 21.59 ±4.59 years for the placebo group), diagnosed with CC (Rome IV criteria)
- The male to female ratio was 15–63 and 17–68 in probiotic and placebo groups respectively
- Groups were standardised with no differences observed in baseline age, gender ratio, drug treatment, high-fibre diet and smoking between the two groups (P >0.18)
- Participants were randomly assigned to the probiotic Lactiplantibacillis plantarum P9 (n=78; 2 g per sachet, 1 ×1011 CFU/day) or the placebo (n =85; maltodextrin powder) groups.
Results
Primary outcomes: weekly mean complete spontaneous bowel movements (CSBMs):
- At 28-days CSBM was 28% higher in the P9 group (P=0.039) compared with the placebo group
- At 42-days CSBM remained significantly higher in the P9 group (P=0.026) compared with the placebo group, and increased 2-fold compared with baseline (P <0.05)
- Authors noted that the CSBM benefits were maintained even after 14 days of not taking the supplement.
Secondary outcomes: The effects of P9 supplementation on constipation-related parameters, including the weekly mean frequency of spontaneous bowel movements (SBMs) demonstrated:
- After 28-days of P9 supplementation, SBMs were 12% higher than the placebo group (P=0.039)
- No differences were observed in the weekly mean stool consistency and straining scores between groups (P>0.05).
Patients’ quality of life and psychological state, using a PAC-QOL questionnaire related to: worries and concerns (WO), physical discomfort, psychosocial discomfort, and satisfaction and found:
- At day 14 WO in the P9 group was 1.22-fold lower than those in the placebo group (P <0.05)
- No differences in the other 3 items between P9 and placebo groups (P >0.05) were observed
- Supplementation resulted in a significant change in relative abundance of the P9 genome (≥0.01%)
- However, no differences were observed in alpha diversity after P9 consumption compared with placebo.
Conclusion
- The results indicated that P9 administration alleviated patients’ constipation symptoms and improved their quality of life but did not impact on gut bacteria or phageome
- Lactiplantibacillis plantarum P9 supplementation impacted several beneficial bacteria species (e.g. (Lactiplantibacillus plantarum and Ruminococcus_B gnavus), and reduced levels of other bacteria and phage taxa (e.g. Oscillospiraceae sp., Lachnospiraceae sp., and Herelleviridae) which may be implicated in constipation relief mechanisms.
Clinical practice applications:
- In this study, the use of P9 administration significantly improved patients’ defecation frequency which could have beneficial implications for patients suffering from chronic constipation
- Probiotic effects are known to be strain- and host-specific, and based on this study P9 administration for relief of constipation needs to be taken for at least two weeks to improve aspects of patients’ quality of life and 4 weeks for improvements in constipation.
Considerations for future research:
- Future trials should include factors that impact gut motility and constipation symptoms, such as: a detailed daily diet (dietary composition, fibre content, and water intake) and physical activity scale (intensity and duration), and longer term use of P9 or comparison across strains
- The relatively small study size and short duration of this study, as well as the younger age groups included may be pertinent when considering future research.
Abstract
Chronic constipation (CC) is a common gastrointestinal condition associated with intestinal inflammation, and the condition considerably impairs patients' quality of life. We conducted a large-scale 42-day randomized, double-blind, placebo-controlled trial to investigate the effect of probiotics in alleviating CC. 163 patients diagnosed with CC (following Rome IV criteria) were randomly divided into probiotic (n = 78; received Lactiplantibacillus plantarum P9 [P9]; 1 ×1011 CFU/day) and placebo (n = 85; received placebo material) groups. Ingesting P9 significantly improved the weekly mean frequency of complete spontaneous bowel movements (CSBMs) and spontaneous bowel movements (SBMs), while significantly reducing the level of worries and concerns (WO; P < 0.05). Comparing with the placebo group, P9 group was significantly enriched in potentially beneficial bacteria (Lactiplantibacillus plantarum and Ruminococcus_B gnavus), while depriving of several bacterial and phage taxa (Oscillospiraceae sp., Lachnospiraceae sp., and Herelleviridae; P < 0.05). Interesting significant correlations were also observed between some clinical parameters and subjects' gut microbiome, including: negative correlation between Oscillospiraceae sp. and SBMs; positive correlation between WO and Oscillospiraceae sp., Lachnospiraceae sp. Additionally, P9 group had significantly (P < 0.05) more predicted gut microbial bioactive potential involved in the metabolism of amino acids (L-asparagine, L-pipecolinic acid), short-/medium-chain fatty acids (valeric acid and caprylic acid). Furthermore, several metabolites (p-cresol, methylamine, trimethylamine) related to the intestinal barrier and transit decreased significantly after P9 administration (P < 0.05). In short, the constipation relief effect of P9 intervention was accompanied by desirable changes in the fecal metagenome and metabolome. Our findings support the notion of applying probiotics in managing CC.
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Physical Training and Healthy Diet Improved Bowel Symptoms, Quality of Life, and Fatigue in Children With Inflammatory Bowel Disease.
Scheffers, LE, Vos, IK, Utens, EMWJ, Dieleman, GC, Walet, S, Escher, JC, van den Berg, LEM
Journal of pediatric gastroenterology and nutrition. 2023;77(2):214-221
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Inflammatory bowel disease (IBD), including Crohn disease and ulcerative colitis, are chronic inflammatory diseases of the gastrointestinal tract, characterised by periods of remission and relapse of symptoms. The aim of this study was to assess the effects of a tailored lifestyle intervention on physical fitness (maximal and submaximal exercise capacity, strength, and core stability), the patient-reported outcomes (quality of life, fatigue, and fear), clinical disease activity, and nutritional status. This study was a prospective single-centre randomised semi-crossover-controlled trial. Children were randomized into group A (start exercise) or group B (start control period). Results showed improved physical fitness, quality of life, and parent-reported fatigue. Additionally, a combination of lower clinical disease activity scores accompanied by fewer IBD symptoms suggests positive effects on intestinal inflammation. Authors concluded that based on the findings of their study, children and adolescents with IBD should be motivated and supported to acquire and maintain a healthy lifestyle.
Expert Review
Conflicts of interest:
None
Take Home Message:
- IBD is a chronic inflammatory disease of the gastrointestinal tract, characterised by periods of abdominal pain, severe diarrhoea, and fatigue
- This clinical trial suggests that a 12-week program of physical training plus personalised healthy dietary advice may improve physical fitness, quality of life, and fatigue in children with IBD.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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X
B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
A randomised semi-crossover controlled trial was conducted to investigate the impact of a 12-week lifestyle program (3 physical training sessions per week plus personalised healthy dietary advice) in children with Inflammatory Bowel Disease (IBD).
Method
- Sixteen children with a median age of 15 [IQR: 12–16]) that were diagnosed with IBD (CD, UC, or IBD-unclassified) were randomized to group A (start exercise) or group B (start control period). Group A started the intervention immediately after the first assessment and did not have a control period. Group B started after a control period (this was planned to last for 6 weeks but due to the COVID-19 lockdown extended to 6 months)
- The lifestyle intervention lasted 12 weeks and consisted of 3 physiotherapist-supervised training sessions per week, lasting 60 minutes each. In addition, all participants received a recommended caloric intake per day based on measured rest energy expenditure and a brochure regarding healthy diet in children
- Endpoints were physical fitness (maximal and submaximal exercise capacity, strength, and core stability), patient-reported outcomes (quality of life, fatigue, and fears for exercise), clinical disease activity (faecal calprotectin and disease activity scores), and nutritional status (energy balance and body composition)
- A total of 15 out of 16 participants (93%) completed the program, one patient dropped out after one training session due to motivational problems.
Results
The primary findings of this study were as follows:
- While medical treatment remained unchanged, Paediatric Crohn's Disease Activity Index decreased versus the control period (15 [3–25] vs 2.5 [0–5], P = 0.012)
- The number of patients in clinical remission increased from 5 to 12 (P < 0.001), compared to the control period
- Quality of life (IMPACT-III) improved on 4 out of 6 domains and the total score (+13 points) versus the control period including a large improvement in bowel-related symptoms, P= 0.029)
- Fecal calprotectin decreased, but not compared to the control period, mainly due to relatively large intra-patient fluctuations (400 μg/g [57.1–1662.7] vs 128 μg/g [23.8–642.3], P = 0.016)
- Parents reported an improvement in the quality of life versus the control period on the child health questionnaire and total fatigue score (PedsQoL • Multidimensional Fatigue Scale) (+14 points, P = 0.048)
- Walking distance improved after the 12-week program, compared to the control period (P = 0.001).
Conclusion
This study revealed that a 12-week physical training program and personalised dietary advice improved bowel symptoms, quality of life, and fatigue in children with IBD.
Clinical practice applications:
- The mechanism behind the anti-inflammatory effects of exercise has not been clarified
- Multiple theories have been suggested in previously published studies such as a reduced release of adipokines due to less visceral fat, increased secretion of anti-inflammatory cytokines such as interleukin (IL)-6, and reduced transient stool time
- This clinical trial demonstrated that a 12-week program of physical training sessions plus personalised healthy dietary advice resulted in improved physical fitness, quality of life, and parent-reported fatigue.
Considerations for future research:
- A sample size calculation was not provided in the study report and it is therefore assumed that the sample size of 16 children in this trial was too small to draw a definite conclusion. A larger study over a longer period is therefore needed across diverse age and ethnic population groups to draw better conclusions
- This study did not measure mucosal inflammation before and after the intervention due to the invasive nature of the procedure. It would however be useful that future research investigate this to gain more insight into the effect of lifestyle interventions on IBD.
Abstract
OBJECTIVES Physical activity programs have been suggested as adjunctive therapy in adult inflammatory bowel disease (IBD) patients. We assessed the effects of a 12-week lifestyle intervention in children with IBD. METHODS This study was a randomized semi-crossover controlled trial, investigating a 12-week lifestyle program (3 physical training sessions per week plus personalized healthy dietary advice) in children with IBD. Endpoints were physical fitness (maximal and submaximal exercise capacity, strength, and core stability), patient-reported outcomes (quality of life, fatigue, and fears for exercise), clinical disease activity (fecal calprotectin and disease activity scores), and nutritional status (energy balance and body composition). Change in maximal exercise capacity (peak VO 2 ) was the primary endpoint; all others were secondary endpoints. RESULTS Fifteen patients (median age 15 [IQR: 12-16]) completed the program. At baseline, peak VO 2 was reduced (median 73.3% [58.8-100.9] of predicted). After the 12-week program, compared to the control period, peak VO 2 did not change significantly; exercise capacity measured by 6-minute walking test and core-stability did. While medical treatment remained unchanged, Pediatric Crohn's Disease Activity Index decreased significantly versus the control period (15 [3-25] vs 2.5 [0-5], P = 0.012), and fecal calprotectin also decreased significantly but not versus the control period. Quality of life (IMPACT-III) improved on 4 out of 6 domains and total score (+13 points) versus the control period. Parents-reported quality of life on the child health questionnaire and total fatigue score (PedsQoL Multidimensional Fatigue Scale) also improved significantly versus the control period. CONCLUSIONS A 12-week lifestyle intervention improved bowel symptoms, quality of life, and fatigue in pediatric IBD patients.
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5.
Probiotics fortify intestinal barrier function: a systematic review and meta-analysis of randomized trials.
Zheng, Y, Zhang, Z, Tang, P, Wu, Y, Zhang, A, Li, D, Wang, CZ, Wan, JY, Yao, H, Yuan, CS
Frontiers in immunology. 2023;14:1143548
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Intestinal barrier function is closely related to the pathogenesis of various immune and inflammatory diseases. The intestinal microbiota plays an essential role in maintaining gut homeostasis and functionality in the presence of pro-inflammatory and anti-inflammatory microbes. The aim of this study was to comprehensively evaluate the role of probiotics in contributing to intestinal barrier function, and the related immune function, inflammatory status, and gut microbiota composition. This study was a systematic review of 28 articles (qualitative synthesis), and a meta-analysis of 26 randomised controlled trials. Results showed that probiotics could significantly improve intestinal barrier function according to specific indicators. The meta-analysis also indicated that probiotic supplementation could reduce inflammatory factors. Furthermore, it also demonstrated that probiotics could modulate gut microbiota compositions by elevating the abundances of Bifidobacterium and Lactobacillus. Authors conclude that probiotics could improve intestinal barrier function to some extent, but more high-quality randomised controlled studies are needed to reach a solid conclusion.
Expert Review
Conflicts of interest:
None
Take Home Message:
The probiotics Bifidobacterium and Lactobacillus may be beneficial for health by addressing imbalances in gut bacteria (dysbiosis), reducing inflammation in the gut and improving the integrity and function of the gut barrier
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
Probiotics are microorganisms that are considered beneficial to health. The aim of this study was to assess the role of probiotics in protecting intestinal barrier function as well as their effects on the composition of gut microbiota, inflammatory status, and immune function for reducing the risk of related diseases.
Methods
26 randomised controlled trials (RCTs) published between 2005-2021 with a total population of n=1891 (n = 955 Intervention, n = 936 controls)) were included in the meta-analysis. Outcome measures were categorised under indicators relating to intestinal barrier function, inflammatory markers, immune function and microbiota composition. Studies were conducted worldwide with participants being healthcare patients or athletes. Study durations ranged from 3 days to 6 months. Different dosages and forms of probiotics were used. Data was pooled for Bifidobacterium, Lactobacillus, Enterobacteriaceae and Enterococcus species.
Results
Gut barrier function in the probiotic groups was improved as measured by transepithelial resistance (TER) mean difference (MD) 5.27 {95% CI, 3.82 to 6.72, p = < 0.00001], lipopolysaccharide (LPS) standardised mean difference (SMD) -0.47 (95% CI, -0.85 to -0.09, p = 0.02), serum zonulin SMD -1.58 (95% CI,-2.49 to -0.66, p = 0.0007), and endotoxin SMD -3.20 (95% CI, -5.41 to - 0.98, p = 0.005).
The inflammatory markers interleukin 6 (IL-6), C-reactive protein (CRP) and tumour necrosis factor-alpha (TNF-a) were also improved compared to control groups. Lactobacillus (95% CI p=0.02) and Bifidobacterium (95% CI, p=0.01) enhanced microbial composition, however, Enterobacteriaceae and Enterococcus species did not. Immune function as measured by Immunoglobulin A (IgA), Immunoglobulin G IgG and Immunoglobulin M (IgM) were not improved.
Conclusion
The findings of this study suggest that intestinal barrier function and microbial composition could be improved using probiotics. They were also found to help alleviate inflammation. Further studies of high quality are however needed to confirm these results.
No conflicts of interest were reported.
Clinical practice applications:
The use of the probiotics Bifidobacterium and Lactobacillus may be beneficial for:
- supporting the integrity of gut barrier function
- improving the composition of gut microbiota
- lowering inflammation
Considerations for future research:
High heterogeneity between studies may affect the applicability of the results. Future research development should focus on the following areas:
- testing methods
- study durations
- measuring indicators
- the type and dose of probiotics
Abstract
BACKGROUND Probiotics play a vital role in treating immune and inflammatory diseases by improving intestinal barrier function; however, a comprehensive evaluation is missing. The present study aimed to explore the impact of probiotics on the intestinal barrier and related immune function, inflammation, and microbiota composition. A systematic review and meta-analyses were conducted. METHODS Four major databases (PubMed, Science Citation Index Expanded, CENTRAL, and Embase) were thoroughly searched. Weighted mean differences were calculated for continuous outcomes with corresponding 95% confidence intervals (CIs), heterogeneity among studies was evaluated utilizing I2 statistic (Chi-Square test), and data were pooled using random effects meta-analyses. RESULTS Meta-analysis of data from a total of 26 RCTs (n = 1891) indicated that probiotics significantly improved gut barrier function measured by levels of TER (MD, 5.27, 95% CI, 3.82 to 6.72, P < 0.00001), serum zonulin (SMD, -1.58, 95% CI, -2.49 to -0.66, P = 0.0007), endotoxin (SMD, -3.20, 95% CI, -5.41 to -0.98, P = 0.005), and LPS (SMD, -0.47, 95% CI, -0.85 to -0.09, P = 0.02). Furthermore, probiotic groups demonstrated better efficacy over control groups in reducing inflammatory factors, including CRP, TNF-α, and IL-6. Probiotics can also modulate the gut microbiota structure by boosting the enrichment of Bifidobacterium and Lactobacillus. CONCLUSION The present work revealed that probiotics could improve intestinal barrier function, and alleviate inflammation and microbial dysbiosis. Further high-quality RCTs are warranted to achieve a more definitive conclusion. CLINICAL TRIAL REGISTRATION https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=281822, identifier CRD42021281822.
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6.
B-vitamins, related vitamers, and metabolites in patients with quiescent inflammatory bowel disease and chronic fatigue treated with high dose oral thiamine.
Bager, P, Hvas, CL, Hansen, MM, Ueland, P, Dahlerup, JF
Molecular medicine (Cambridge, Mass.). 2023;29(1):143
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Plain language summary
IBD is characterised by chronic inflammation of the gastrointestinal tract with periodic inactive (quiescent disease) and periodic active inflammation. Chronic fatigue is regarded as elevated fatigue levels with duration of more than 6 months. Malnutrition in patients with IBD is well known and this study assessed changes in B-vitamins and their related metabolites directly after high dose oral thiamine, vitamin B1. 40 adult patients with quiescent IBD and chronic fatigue were randomised compared to a control group of 20 patients without fatigue. In total, 52 females and 8 men took part in the trial. Half of the patients had Crohn’s disease and half had ulcerative colitis. Blood samples were taken and patients answered questionnaires regarding fatigue at each study visit. The researchers found low levels of Flavin mononucleotide (FMN), a biomolecule produced from riboflavin (vitamin B2) in patients with chronic fatigue in comparison to patients without fatigue. The researchers also observed that fatigued IBD patients had a less diverse microbiome with reduced numbers of butyrate-producing bacterial species compared to non-fatigued patients, highlighting the importance of vitamin B1 for the growth of gut bacteria. The oral dose of vitamin B1 administered is unclear and other factors influencing fatigue such as diet, sleep and physical activity were not investigated. The researchers conclude the mechanisms of B-vitamins in IBD in relation to fatigue does require further exploration along with assessing vitamin B2’s effect on IBD fatigue.
Expert Review
Conflicts of interest:
None
Take Home Message:
- This was a small secondary analysis of samples and data from a previous RCT and further investigations would be of benefit to confirm findings.
- However, low plasma B2 vitamin and FMN levels may be associated with chronic fatigue in individuals with IBD.
- Thiamine supplementation may result in higher use of riboflavin and ways to support these should be considered and may improve outcomes in this patient group.
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
Fatigue is considered a symptom of inflammatory bowel disease (IBD), and may be related to nutrient deficiencies and inflammation. Thiamine is an essential vitamin in the biosynthesis of adenosine triphosphate and energy, however deficiency amongst individuals with IBD is not common and so not monitored. This study aimed to compare plasma B vitamin levels, and their related metabolites and vitamers of individuals with quiescent IBD either with fatigue or without fatigue and determine the effect of high dose thiamine on fatigue.
Methods
- This was a secondary analysis of blood plasma samples collected from a previous randomised control trial (RCT), which looked at the supplementation of high dose thiamine on levels of fatigue in individuals with IBD.
- Samples were available from 60 individuals with IBD; 40 individuals with quiescent IBD and chronic fatigue. 20 individuals with quiescent IBD and no fatigue.
- 21 B vitamins and their associated metabolites and vitamers were analysed.
Results
- Of the 21 measures, only flavin mononucleotide (FMN), a B2 vitamer, was different between those with IBD and fatigue and those with IBD without fatigue. Those with fatigue had lower median FMN levels than those without (11.1 nmol/L; IQR 8.4 to 13.7 vs 14.2 nmol/l; IQR 10.9 to 17.0; P= 0.02).
- Thiamine treatment amongst those with fatigue increased thiamine levels, but had no effect on other metabolites or vitamers (statistics not given).
- Individuals with fatigue who improved with thiamine treatment showed a drop in riboflavin levels after therapy was given (P=0.01), whilst all other B vitamins, vitamers, and metabolites stayed the same.
Conclusion
- It was concluded that amongst the vitamers, metabolites, and B vitamins analysed, only FMN and riboflavin are associated with chronic fatigue in individuals with IBD.
Clinical practice applications:
- Low FMN may be involved in the development of fatigue in individuals with IBD.
- This trial did not show if vitamin B2 supplementation would be of benefit to individuals with IBD and chronic fatigue.
- Lower riboflavin levels following thiamine supplementation may be associated with an increase in its use for thiamine mediated ATP production.
- This study may be able to inform future research or support the supplementation of B2 if further research is found.
- Blood plasma levels of other B vitamins and their metabolites and vitamers is unlikely to be related to chronic fatigue in individuals with IBD.
- Use of the IBD fatigue questionnaire may be of utility in clinical practice.
Considerations for future research:
- Larger RCTs, which have been designed to analyse this specific research question are warranted, as this study was conducted in a small number of individuals as a secondary analysis of samples from another RCT.
- Supplementation RCTs of vitamin B2 alone and in combination with thiamine on individuals with IBD and chronic fatigue would be of benefit.
Abstract
BACKGROUND High doses of oral thiamine improve clinical fatigue scores in patients with quiescent inflammatory bowel disease (IBD) and chronic fatigue. In this study we analysed plasma samples obtained in a randomised clinical trial and aimed compare levels of vitamins B1, B2, B3 and B6, and their related vitamers and metabolites in patients with IBD, with or without chronic fatigue and with or without effect of high dose oral thiamine for chronic fatigue. METHODS Blood samples from patients with fatigue were drawn prior and after thiamine exposure and only once for patients without fatigue. A wide panel of analysis were done at Bevital AS Lab. RESULTS Concentration of flavin mononucleotide (FMN) was lower in patients with chronic fatigue compared to patients without fatigue (p = 0.02). Patients with chronic fatigue who reported a positive effect on fatigue after 4 weeks of high dose thiamine treatment had a statistically significantly lower level of riboflavin after thiamine treatment (p = 0.01). CONCLUSION FMN and Riboflavin were associated with chronic fatigue in patients with quiescent IBD. Levels of other B vitamins and metabolites were not significantly different between the investigated groups or related to effect of the thiamine intervention. CLINICAL TRIAL REGISTRATION ClinicalTrials.gov study identifier NCT036347359. Registered 15 August 2018, https://clinicaltrials.gov/study/NCT03634735?cond=Inflammatory%20Bowel%20Diseases&intr=Thiamine&rank=1.
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7.
The vaginal microbiome and the risk of preterm birth: a systematic review and network meta-analysis.
Gudnadottir, U, Debelius, JW, Du, J, Hugerth, LW, Danielsson, H, Schuppe-Koistinen, I, Fransson, E, Brusselaers, N
Scientific reports. 2022;12(1):7926
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Preterm birth is a major cause of neonatal mortality and morbidity. Many factors can trigger premature labour onset, including preterm premature rupture of membranes, infections and microbial invasion of the amniotic cavity. The vaginal microbiome is thought to protect from such infections. The aim of this study was to assess the association between the vaginal microbiome and the risk of preterm birth. This study is a systematic review and meta-analysis of 17 cohort studies. The number of pregnancies per study ranged between 38 and 539, with 8 and 107 preterm births. Results show that women with a “low-lactobacilli” vaginal microbiome composition were at higher risk of preterm birth (spontaneous and overall) compared to women with L. crispatus (microbiome) dominant microbiome compositions. Authors conclude that the diversity of the vaginal microbiome seems to play a part in the risk of preterm birth.
Expert Review
Conflicts of interest:
None
Take Home Message:
- The diversity of the vaginal microbiome is reported to play a part in the risk of preterm births.
- Practitioners could consider testing the virginal microbiome for low Lactobacilli or the dominance of Gardnerella and Prevotella and then recommending a probiotic supplement to pregnant patients who have low Lactobacilli vaginal microbiome.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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X
B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
A systematic review and network meta-analysis was conducted to investigate the association between vaginal microbiome and risk of preterm births.
Methodology
- Seventeen longitudinal cohort studies were included. Seven originated from North America, three from Europe, two from South America, three from Asia, and two from Africa. The number of pregnancies per study ranged between 38 and 539, with 8 and 107 preterm births. 16S Sequencing techniques were used to identify the microbial species. Preterm birth was defined as birth before 37 weeks of gestation.
- Microbiome community state types (CSTs) were grouped into five categories based on dominating species: L. crispatus, L. gasseri, L. iners,“low-lactobacilli” and L. jensenii. “Low-lactobacilli” was defined as an increased diversity of anaerobic or mixture of aerobe and facultative anaerobe bacteria (such as Gardnerella and Prevotella) based on the cut-offs and categorization used in the individual studies.
Results
Primary clinical outcomes were:
- Among women who delivered preterm, the pooled proportion with “low-lactobacilli” was 0.41 (95% CI 0.30-0.53) compared to 0.29 (95% CI 0.20-0.38) of women with full-term deliveries.
- The risk of preterm births was higher among women with “low-lactobacilli” compared to L. crispatus (OR 1.69, 95%CI 1.15 -2.49).”Low-lactobacilli” included Garnerella and Provotella, both of which are known to promote inflammatory cytokines and are commonly found in vaginal microbiome just before preterm premature rupture of membranes (PPROM).
Clinical practice applications:
- The diversity of the vaginal microbiome is reported to play an important role in the risk of preterm births.
- Women with low Lactobacilli seem to be at a greater risk of delivering preterm compared to women with L. crispatus dominant microbiome.
- Based on this study, practitioners could therefore consider testing the vaginal microbiome of their patients for low Lactobacilli and/or the dominance of Gardnerella and Prevotella.
- Practitioners may also consider recommending specific probiotic supplementation during pregnancy to increase the dominance of Lactobacilli and L. crispatus vaginal microbiome.
Considerations for future research:
- In the past, researchers have grouped the microbiome into categories based on dominating species, which is not ideal. Therefore, further studies are needed where individual microbiome sequencing data is used to make comparisons.
- Additionally, longitudinal studies are needed with higher sample sizes to investigate the natural changes of the vaginal microbiome during pregnancy and the physiological mechanisms underlying these apparent different risk profiles.
- Furthermore, randomized-controlled trials are needed to establish if pregnant women could benefit from specific probiotic supplementation during pregnancy.
Abstract
Preterm birth is a major cause of neonatal morbidity and mortality worldwide. Increasing evidence links the vaginal microbiome to the risk of spontaneous preterm labour that leads to preterm birth. The aim of this systematic review and network meta-analysis was to investigate the association between the vaginal microbiome, defined as community state types (CSTs, i.e. dominance of specific lactobacilli spp, or not (low-lactobacilli)), and the risk of preterm birth. Systematic review using PubMed, Web of Science, Embase and Cochrane library was performed. Longitudinal studies using culture-independent methods categorizing the vaginal microbiome in at least three different CSTs to assess the risk of preterm birth were included. A (network) meta-analysis was conducted, presenting pooled odds ratios (OR) and 95% confidence intervals (CI); and weighted proportions and 95% CI. All 17 studies were published between 2014 and 2021 and included 38-539 pregnancies and 8-107 preterm births. Women presenting with "low-lactobacilli" vaginal microbiome were at increased risk (OR 1.69, 95% CI 1.15-2.49) for delivering preterm compared to Lactobacillus crispatus dominant women. Our network meta-analysis supports the microbiome being predictive of preterm birth, where low abundance of lactobacilli is associated with the highest risk, and L. crispatus dominance the lowest.
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8.
Efficacy and Acceptability of Dietary Therapies in Non-Constipated Irritable Bowel Syndrome: A Randomized Trial of Traditional Dietary Advice, the Low FODMAP Diet, and the Gluten-Free Diet.
Rej, A, Sanders, DS, Shaw, CC, Buckle, R, Trott, N, Agrawal, A, Aziz, I
Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association. 2022;20(12):2876-2887.e15
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Irritable bowel syndrome (IBS) is a common disorder characterised by stomach pain, bloating, and altered bowel movements. Dietary therapy is a way to manage IBS, with 3 diets becoming popular amongst health care professionals and those who suffer from IBS. Traditional dietary advice (TD), which involves adopting healthy, sensible eating patterns with adequate hydration, is the first line recommendation in the UK. The low-FODMAP diet (LFD) is the avoidance of carbohydrates, which tend to ferment in the stomach and are found in certain fruits and vegetables. The gluten free diet (GFD) is the avoidance of foods which contain gluten such as bread and pasta. All three diets have little evidence to support their use in IBS and this randomised control trial of 101 individuals with IBS aimed to determine whether the GFD and LFD are superior in relieving IBS symptoms compared to TD. The results showed that GFD, LFD and TD were all effective in the management of non-constipated IBS, but that TD was easier to follow and cheaper compared to the other two diets. It was concluded that TD should be used as first-line therapy for people with non-constipated IBS and that GFD and LFD should be reserved for specific patients under the care of a health care professional.
Expert Review
Conflicts of interest:
None
Take Home Message:
- TDA, LFD and GFD can all lead to significant improvements in non-constipation IBS with no statistically significant difference in effectiveness between the diets.
- Most patients find a TDA easier and cheaper to implement than a LFD or GFD.
- TDA is therefore recommended as a first line approach in non-constipation IBS.
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
The aim of this study was to compare the effectiveness and patient acceptability of traditional dietary advice (TDA) vs a low FODMAP diet (LFD) vs a gluten-free diet (GFD, cross-contamination allowed) in patients with non-constipation irritable bowel syndrome (IBS).
TDA definition: healthy, sensible eating pattern, including regular meals, not eating too little/too much, adequate hydration, and reducing the intake of: alcohol/caffeine/fizzydrinks/fatty/spicy/ processed foods; fresh fruit (maximum of 3 per day); fibre/gas-producing foods and perceived food intolerances.
Methods
This was a randomised dietary trial over 4 weeks. Dietary advice was provided by a specialist dietitian in a session lasting 45-60 minutes. 99 patients completed the study (33 in each group). Stool analysis was performed in “around half“ (study authors terminology) of participants due to disruption of trial caused by COVID-19.
Results:
- Primary endpoint (reduction of 50 points or more on IBS symptom severity score) was met by 42% of patients on the TDA, 55% on LFD and 58% on GFD. The differences between groups were not statistically significant, p=0.43.
- Patients on the LFD had greater improvements in mood compared to the other diets under examination, reaching statistical significance (p=0.03) for Hospital Anxiety and Depression scale and (p<0.01) for dysphoria score on IBS-QOL scale.
- Patients on TDA found their diet cheaper (p<0.01), less time consuming to shop (p<0.01) and easier to follow when eating out with family and friends (p=0.03), whilst TDA and GFD were considered easier to incorporate into daily diet than LFD (p=0.02).
- No significant differences were found between groups in changes to macro- and micronutrient composition, except a trend to lower fibre intake with LFD (p=0.06).
- There was a significant reduction in intake of FODMAPs in all groups, with greatest reduction in LFD (27.7 to 7.6 g/day, p<0.01), followed by TDA (24.9 to 15.2 g/day, p<0.01) and GFD (27.4 to 22.4 g/day, p=0.03). Differences between groups were statistically significant (p<0.01).
- No differences were noted in change to the dysbiosis index between groups.
- Neither clinical characteristics nor dysbiosis index predicted response to any of the diets.
Conclusion
- TDA, LFD and GFD are all effective approaches for non-constipation IBS.
- TDA should be first-line dietary advice due to being the most patient-friendly.
Clinical practice applications:
- When working with clients with non-constipation IBS, a TDA approach may be favoured over LFD and GFD as a first line intervention if the patient has not already tried a TDA diet.
- Patient preferences, budget, time and living situation should be taken into account when deciding on best dietary advice for IBS.
Considerations for future research:
- As all 3 approaches led to reduction in FODMAPs, trials comparing different levels of FODMAP exclusion could lead to valuable information, as a strict FODMAP exclusion, which is commonly recommended in IBS, is difficult and may not be necessary.
- Studies of longer duration would be valuable to confirm that benefits observed with the 3 approaches are not short-term only.
- Comparing individual approaches to appropriate control group would ensure that improvements are not due to a placebo effect.
Abstract
BACKGROUND & AIMS Various diets are proposed as first-line therapies for non-constipated irritable bowel syndrome (IBS) despite insufficient or low-quality evidence. We performed a randomized trial comparing traditional dietary advice (TDA) against the low FODMAP diet (LFD) and gluten-free diet (GFD). METHODS Patients with Rome IV-defined non-constipated IBS were randomized to TDA, LFD, or GFD (the latter allowing for minute gluten cross-contamination). The primary end point was clinical response after 4 weeks of dietary intervention, as defined by ≥50-point reduction in IBS symptom severity score (IBS-SSS). Secondary end points included (1) changes in individual IBS-SSS items within clinical responders, (2) acceptability and food-related quality of life with dietary therapy, (3) changes in nutritional intake, (4) alterations in stool dysbiosis index, and (5) baseline factors associated with clinical response. RESULTS The primary end point of ≥50-point reduction in IBS-SSS was met by 42% (n = 14/33) undertaking TDA, 55% (n = 18/33) for LFD, and 58% (n = 19/33) for GFD (P = .43). Responders had similar improvements in IBS-SSS items regardless of their allocated diet. Individuals found TDA cheaper (P < .01), less time-consuming to shop (P < .01), and easier to follow when eating out (P = .03) than the GFD and LFD. TDA was also easier to incorporate into daily life than the LFD (P = .02). Overall reductions in micronutrient and macronutrient intake did not significantly differ across the diets. However, the LFD group had the greatest reduction in total FODMAP content (27.7 g/day before intervention to 7.6 g/day at week 4) compared with the GFD (27.4 g/day to 22.4 g/day) and TDA (24.9 g/day to 15.2 g/day) (P < .01). Alterations in stool dysbiosis index were similar across the diets, with 22%-29% showing reduced dysbiosis, 35%-39% no change, and 35%-40% increased dysbiosis (P = .99). Baseline clinical characteristics and stool dysbiosis index did not predict response to dietary therapy. CONCLUSIONS TDA, LFD, and GFD are effective approaches in non-constipated IBS, but TDA is the most patient-friendly in terms of cost and convenience. We recommend TDA as the first-choice dietary therapy in non-constipated IBS, with LFD and GFD reserved according to specific patient preferences and specialist dietetic input. CLINICALTRIALS gov: NCT04072991.
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9.
Low FODMAP diet reduces gastrointestinal symptoms in irritable bowel syndrome and clinical response could be predicted by symptom severity: A randomized crossover trial.
Algera, JP, Demir, D, Törnblom, H, Nybacka, S, Simrén, M, Störsrud, S
Clinical nutrition (Edinburgh, Scotland). 2022;41(12):2792-2800
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Irritable bowel syndrome (IBS) is a common disorder of gut-brain interaction, characterised by chronic abdominal pain and altered bowel habits. Currently, many patients follow an exclusion diet where specific food components are eliminated. One of these exclusion diets is a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs). The primary aim of this study was to compare the effects of diets with low vs. moderate FODMAP content on gastrointestinal (GI) symptoms in IBS. This study was a double-blind, randomised, controlled, crossover study which enrolled 31 participants who were randomly assigned to the diet periods. Results showed that the severity of GI symptoms was reduced, and bowel habits were affected in the direction of less frequent and firmer stool by the low FODMAP diet, but not by a diet with moderate amounts of FODMAPs. Authors conclude that assessment of overall IBS severity and predominant bowel habits before the intervention may be helpful for clinicians in their IBS management before considering a trial period with the low FODMAP diet as a treatment option.
Expert Review
Conflicts of interest:
None
Take Home Message:
A low (4 g/day) FODMAP diet could provide clinical benefits in the context of an acute strategy for IBS clients with frequent loose stools (IBS-Diarrhoea and/or IBS-Mixed) compared to those with hard and less frequent stools (IBS-Constipation) to improve the severity of GI symptoms, including lower abdominal pain intensity and frequency, bowel habits, daily life interference, and psychological distress.
Evidence Category:
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X
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
The aim of this paper was to investigate the effects of diets with low vs. moderate FODMAP content on gastrointestinal (GI) symptoms and bowel habits, and to identify possible predictors of clinical response to a low FODMAP diet and FODMAP sensitivity in Irritable Bowel Syndrome (IBS).
Methods
- This study involved a double-blind, randomised, controlled, crossover trial of 29 participants (18-75 years), mostly female, diagnosed with IBS (Rome IV)
- The primary outcome was to assess the effects of a low (4 g/day) vs. moderate (23 g/day) FODMAP diet on GI symptoms over a 7-day period
- Secondary outcomes involved assessing the effects of low vs. moderate FODMAP diets on i) somatic symptoms, ii) psychological distress, iii) predictors of clinical and IBS-Severity Scoring System (IBS-SSS) sensitivity to FODMAP
- Breakfast was standardised, with prescribed low FODMAP list deviations recorded
- Main dishes and snacks were also provided
- Participants were requested to limit alcohol, caffeine, fatty- and spicy foods, ate regularly, chewed thoroughly and drank enough water
- GI symptoms and bowel habits were recorded during the 7-day screening period, then participants undertook a Lactulose Nutrient Challenge Test (LNCT)
- The first 7-day diet started one day after the LNCT
- A 14-day wash-out period allowed participants to eat and drink as usual, thereafter following the second 7-day diet period as part of the cross over design.
Results
A low FODMAP intervention (compared to a moderate FODMAP diet); resulted in:
- Reduced overall IBS rating (10 ± 72 vs. 57 ± 108, P=0.04)
- Improved abdominal pain frequency (10 ± 32 vs. 18 ± 29 (P=0.02)
- Improved stool consistency (0.2 ± 1.0 vs. 0.6 ± 1.2, P= 0.01) and frequency (0.1 ± 0.7 vs. 0.4 ± 0.7, P= 0.01)
- Overall, 34% of participants positively responded to the low FODMAP diet, which could be predicted based on higher baseline IBS-SSS scores (P=0.02)
- Participants sensitive to FODMAPs had increased pre- and postprandial ratings of gas, abdominal pain and bloating and higher exhaled methane concentrations compared to non-sensitive participants to FODMAPs
- Authors highlighted a non-significant association between FODMAP sensitivity and GI symptoms during the LNCT, with higher visceral hypersensitivity (45 ± 20, P=0.73) after ingestion of poorly absorbed and fermentable carbohydrates, with no independent predictors identified.
Conclusions
This study showed that a diet low in FODMAPs reduces GI symptoms and positively impacts bowel habits in IBS, compared with a moderate FODMAP diet.
Clinical practice applications:
- While this was a short term study, a low FODMAP diet reduced GI symptoms and affected bowel habits (more firm and less frequent stools) in IBS, compared with a diet containing moderate amounts of FODMAPs
- Knowing the above, an assessment of overall IBS severity and predominant bowel habits before the intervention may be helpful for clinicians working with younger females in their IBS management before considering a trial period with the low FOD-MAP diet as a treatment option.
Considerations for future research:
- Future trials could target a larger sample size with a more representative population, as well as assessing low FODMAP interventions over longer timeframes
- . Additionally, the assessment of biological measures such as microbiota diversity and stability, as well as metabolites (such as short chain fatty acids) could be important to understand mechanistic attributes of low FODMAP diets in IBS.
Abstract
BACKGROUND & AIMS Fermentable oligo-, di-, monosaccharides and polyols (FODMAPs) can provoke symptoms in patients with irritable bowel syndrome (IBS). We aimed to compare the effects of diets with low vs. moderate FODMAP content on gastrointestinal (GI) symptoms and bowel habits, and to identify possible predictors of clinical response to a low FODMAP diet and FODMAP sensitivity in IBS. METHODS Adult participants with IBS (Rome IV criteria, n = 29) were included and adhered to two 7-day diet periods, with either low (4 g/day) or moderate (23 g/day) amounts of FODMAPs, in this randomized, double-blind, crossover study. The periods were separated by a wash-out period (≥14 days). IBS-Severity Scoring System (IBS-SSS) and a stool diary (Bristol Stool Form) were completed before and after the diet periods. At baseline, severity of GI symptoms and gut microbial fermentation were assessed (every 15 min, 4 h) during the Lactulose Nutrient Challenge Test (LNCT). Clinical response and FODMAP sensitivity were defined by reduction after low FODMAP period, and increase after moderate FODMAP period in IBS-SSS (≥50 points), respectively. RESULTS Severity of GI symptoms (P = 0.04), stool consistency (P = 0.01), and stool frequency (P = 0.01) differed between the interventions, with reduced overall GI symptom severity, abdominal pain intensity and frequency, bowel habits dissatisfaction, and daily life interference (P < 0.05 for all), as well as more firm (P = 0.03) and less frequent (P < 0.01) stools after low FODMAP intervention, but not after moderate FODMAP intervention. A third (34%) responded clinically to the low FODMAP diet, and the response could be predicted by higher IBS-SSS at baseline (P = 0.02). Although modest associations between FODMAP sensitivity (22%) and GI symptoms during LNCT were observed, no independent predictors could be identified. CONCLUSIONS A diet low in FODMAPs reduces GI symptoms and affects bowel habits in IBS, compared with a moderate FODMAP diet. Assessment of IBS severity before the intervention may be used to predict clinical response to a low FODMAP diet. Trial registry (http://www. CLINICALTRIALS gov): Registered under Clinical Trial number NCT05182593.
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10.
Effects of Lactococcus lactis subsp. cremoris YRC3780 daily intake on the HPA axis response to acute psychological stress in healthy Japanese men.
Matsuura, N, Motoshima, H, Uchida, K, Yamanaka, Y
European journal of clinical nutrition. 2022;76(4):574-580
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The hypothalamic-pituitary-adrenal (HPA) axis is involved in the stress response and is linked to the microbiome through a number of possible mechanisms, including immune-related ones. Lactococcus lactis subsp. cremoris YRC3780 (YRC3780), a probiotic isolated from kefir, has been shown to have beneficial immune-modulatory properties. The aim of this double-blind, placebo-controlled trial, which included 27 healthy young men, was to assess sleep quality, mental health, HPA axis activity (salivary cortisol) and response to an acute stress test during/after 8 weeks of supplementation with YRC3780. At 8 weeks, salivary morning cortisol levels were significantly reduced in the probiotic compared to the placebo group. The effect on the stress test depended on whether or not participants were considered “cortisol-responders” or not. Improvements in sleep quality were seen at 6 weeks (but not at any other time points) in 1 out of 2 sleep questionnaires in the YRC3780 group, whilst no significant differences were observed in actigraphy-measured sleep efficiency. There were no differences in mood between groups, but significant improvements in general health in the probiotic group. Interestingly, no changes in the microbiome of the probiotic group were seen, suggesting that the observed effects may be mediated via the immune system.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Research indicates a bidirectional interaction between the gut microbiome and the central nervous system, affecting the functions of the brain and spinal cord.
- This clinical trial suggests that daily intake of Lactococcus lactis subsp. cremoris (YRC3780) may enhance the HPA axis response to acute psychological stress, potentially linked to a reduction in morning cortisol levels.
Evidence Category:
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A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
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X
B: Systematic reviews including RCTs of limited number
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C: Non-randomized trials, observational studies, narrative reviews
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D: Case-reports, evidence-based clinical findings
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E: Opinion piece, other
Summary Review:
Introduction
A randomized, placebo-controlled, double-blind clinical trial was conducted to investigate the influence of Lactococcus lactis subsp. cremoris (YRC3780), isolated from kefir, on stress response, sleep quality, and mental health.
Method
Twenty-seven healthy young men, with an average age of 23.5 years, and mean body mass index of 21.5 kg/m2 , were randomly assigned to either the YRC3780 group or the placebo group. Participants were administered YRC3780 or a placebo daily for 8 weeks.
Throughout the study, participants completed assessments, including the Athens Insomnia Scale (AIS), the Pittsburgh Sleep Quality Index (PSQI), the General Health Questionnaire (GHQ-28), and the Profile of Mood States 2nd Edition-Adult Short, Total Mood Disturbance subscale (POMS 2 TMD), every 2 weeks. Additionally, diurnal rhythms of HPA axis activity were assessed every 2 weeks through saliva samples collected at 2-hour intervals during the day. At the end of the 8-week supplementation period, participants underwent the Trier Social Stress Test (TSST) to evaluate the effects of daily YRC3780 intake on the HPA axis stress response. In addition, three fecal samples were collected to analyse the gut microbiome (on the last day of baseline, and at 4 and 8 weeks).
A total of 27 out of 33 subjects (81%) completed the study, with six participants withdrawing without providing explanations.
Results
The primary findings of this study were as follows:
- At week 6 of YRC3780 supplementation, salivary cortisol levels at 2 hours and 6 hours after waking were significantly lower in the YRC3780 group compared to the placebo group (p=0.05).
- Salivary cortisol concentrations at 40 minutes after the TSST were significantly lower in the YRC3780 group (4.2 ± 4.4 nmol/L, mean ± SD) than in the placebo group (7.6 ± 4.7 nmol/L) (p=0.043).
- AIS scores at 6 weeks and GHQ-28 scores at 8 weeks were significantly lower in the YRC3780 group compared to the placebo group (AIS, p=0.031; GHQ-28, p=0.038) indicating better sleep quality and a better mental state.
Conclusion:
Oral supplementation with YRC3780 may have beneficial effects on the HPA axis response to acute psychological stress, potentially associated with a decrease in morning cortisol levels. Additionally, the study suggests that the lower basal activity and stress reactivity of the HPA axis may lead to improvements in subjective sleep quality and mental health.
Clinical practice applications:
- The precise mechanisms underlying the correlation between the gut microbiota and the gut-brain axis remain incompletely understood, emphasising the need for further research.
- This clinical trial demonstrated that daily intake of YRC3780 decreased morning salivary cortisol levels at 6 and 8 weeks and reduced the salivary cortisol response to acute psychological stress.
Considerations for future research:
- Larger, adequately powered clinical trials are required to provide deeper insights into the mechanisms responsible for the stress-reducing and sleep-improving effects of Lactococcus lactis subsp. cremoris.
- Furthermore, investigations into optimal dosage and duration of probiotic supplementation are warranted for a more comprehensive understanding, particularly in diverse demographic groups.
- Comparative research is needed to explore the effects of various probiotic strains on objective stress responses.
Abstract
BACKGROUND Lactococcus lactis subsp. cremoris (YRC3780), which is isolated from kefir, has been associated with anti-allergic effects in humans. However, it remains unknown whether daily intake of YRC3780 attenuates the response to psychological stress in humans in parallel with changes to the gut microbiome. We examined the fundamental role of YRC3780 in the gut microbiome, stress response, sleep, and mental health in humans. METHODS Effects of daily intake of YRC3780 on the hypothalamic-pituitary-adrenal (HPA) axis response to acute psychological stress were investigated in a double-blind, placebo-controlled clinical trial involving 27 healthy young men (mean age and body mass index: 23.5 years and 21.5 kg/m2) who were randomly assigned to placebo (n = 13) or YRC3780 (n = 14) groups. The HPA axis response to acute psychological stress, the diurnal rhythm of HPA axis activity, and gut microbiome were assessed and compared between the two groups. RESULTS The results showed that daily intake of YRC3780 significantly lowered morning salivary cortisol levels compared with placebo. In addition, salivary cortisol levels following a social stress test significantly decreased +40 min after beginning the TSST in the YRC3780-treated group compared to placebo. There were no significant differences between the two groups in terms of actigraphy-based sleep quality, but the subjective sleep quality and mental health were significantly improved in the YRC3780-treated group compared to placebo. CONCLUSIONS Our study suggests that daily intake of YRC3780 improves the HPA axis response to acute psychological stress, which might be associated with a decrease in morning cortisol levels.