-
1.
More Than 50 Long-Term Effects of COVID-19: A Systematic Review and Meta-Analysis.
Lopez-Leon, S, Wegman-Ostrosky, T, Perelman, C, Sepulveda, R, Rebolledo, P, Cuapio, A, Villapol, S
Research square. 2021
-
-
-
Free full text
Plain language summary
Symptoms, signs, or abnormal clinical parameters persisting two or more weeks after COVID-19 onset that do not return to a healthy baseline can potentially be considered long-term effects of the disease. The aim of this study was to estimate the incidence of all the symptoms, signs, or abnormal laboratory parameters extending beyond the acute phase of COVID-19 reported to date. This study is a systematic review and meta-analysis of 15 peer-reviewed studies that reported symptoms, signs, or laboratory parameters of patients at a post-COVID-19 stage (assessed two weeks or more after initial symptoms) in cohorts of COVID-19 patients. Results indicate that 80% (95% CI 65–92) of individuals with a confirmed COVID-19 diagnosis continued to have at least one overall effect beyond two weeks following acute infection. In total, 55 effects, including symptoms, signs, and laboratory parameters, were identified, with fatigue, anosmia [partial or complete loss of the sense of smell], lung dysfunction, abnormal chest X-ray/CT scan, and neurological disorders being the most common. Authors conclude that physicians should be aware of the symptoms, signs, and biomarkers present in patients previously affected by COVID-19 to promptly assess, identify and halt long COVID-19 progression, minimize the risk of chronic effects and help re-establish pre-COVID-19 health.
Abstract
Background. COVID-19, caused by SARS-CoV-2, can involve sequelae and other medical complications that last weeks to months after initial recovery, which has come to be called Long-COVID or COVID long-haulers. This systematic review and meta-analysis aims to identify studies assessing long-term effects of COVID-19 and estimates the prevalence of each symptom, sign, or laboratory parameter of patients at a post-COVID-19 stage. Methods . LitCOVID (PubMed and Medline) and Embase were searched by two independent researchers. All articles with original data for detecting long-term COVID-19 published before 1 st of January 2021 and with a minimum of 100 patients were included. For effects reported in two or more studies, meta-analyses using a random-effects model were performed using the MetaXL software to estimate the pooled prevalence with 95% CI. Heterogeneity was assessed using I 2 statistics. This systematic review followed Preferred Reporting Items for Systematic Reviewers and Meta-analysis (PRISMA) guidelines, although the study protocol was not registered. Results. A total of 18,251 publications were identified, of which 15 met the inclusion criteria. The prevalence of 55 long-term effects was estimated, 21 meta-analyses were performed, and 47,910 patients were included. The follow-up time ranged from 14 to 110 days post-viral infection. The age of the study participants ranged between 17 and 87 years. It was estimated that 80% (95% CI 65-92) of the patients that were infected with SARS-CoV-2 developed one or more long-term symptoms. The five most common symptoms were fatigue (58%), headache (44%), attention disorder (27%), hair loss (25%), and dyspnea (24%). All meta-analyses showed medium (n=2) to high heterogeneity (n=13). Conclusions . In order to have a better understanding, future studies need to stratify by sex, age, previous comorbidities, the severity of COVID-19 (ranging from asymptomatic to severe), and duration of each symptom. From the clinical perspective, multi-disciplinary teams are crucial to developing preventive measures, rehabilitation techniques, and clinical management strategies with whole-patient perspectives designed to address long COVID-19 care.
-
2.
SARS-CoV-2 and immune-microbiome interactions: Lessons from respiratory viral infections.
Cyprian, F, Sohail, MU, Abdelhafez, I, Salman, S, Attique, Z, Kamareddine, L, Al-Asmakh, M
International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases. 2021;105:540-550
-
-
-
Free full text
Plain language summary
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an enveloped RNA beta-coronavirus. This virus caused the coronavirus disease 2019 (COVID-19) pandemic. The aim of this review was to investigate the relationship between microbiota, immunity, and COVID-19, with particular focus on how microbiome-associated immune crosstalk can shape outcome of COVID-19. The study included 118 articles which investigated or reviewed COVID-19 or coronavirus and the microbiome of the gut or respiratory tract. Findings indicate that: - an over-activated immune system leads to massive pulmonary damage in COVID-19 patients. - the effect of aging and comorbidities, and the use of antibiotics have an effect on the diversity of the microbiota. - the milieu of gut flora can exert influence on pulmonary immune responses. - a unique cross-talk exists between the pulmonary and gut microbial compartments. Authors conclude by highlighting the need of further studies that delineate the role of the microbiota and their products in the immune dysregulation observed in SARS-CoV-2 infections.
Abstract
By the beginning of 2020, infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had rapidly evolved into an emergent worldwide pandemic, an outbreak whose unprecedented consequences highlighted many existing flaws within public healthcare systems across the world. While coronavirus disease 2019 (COVID-19) is bestowed with a broad spectrum of clinical manifestations, involving the vital organs, the respiratory system transpires as the main route of entry for SARS-CoV-2, with the lungs being its primary target. Of those infected, up to 20% require hospitalization on account of severity, while the majority of patients are either asymptomatic or exhibit mild symptoms. Exacerbation in the disease severity and complications of COVID-19 infection have been associated with multiple comorbidities, including hypertension, diabetes mellitus, cardiovascular disorders, cancer, and chronic lung disease. Interestingly, a recent body of evidence indicated the pulmonary and gut microbiomes as potential modulators for altering the course of COVID-19, potentially via the microbiome-immune system axis. While the relative concordance between microbes and immunity has yet to be fully elucidated with regards to COVID-19, we present an overview of our current understanding of COVID-19-microbiome-immune cross talk and discuss the potential contributions of microbiome-related immunity to SARS-CoV-2 pathogenesis and COVID-19 disease progression.
-
3.
'Long COVID': persistent COVID-19 symptoms in survivors managed in Lagos State, Nigeria.
Osikomaiya, B, Erinoso, O, Wright, KO, Odusola, AO, Thomas, B, Adeyemi, O, Bowale, A, Adejumo, O, Falana, A, Abdus-Salam, I, et al
BMC infectious diseases. 2021;21(1):304
-
-
-
Free full text
Plain language summary
The spectrum of clinical presentation of COVID-19 ranges from the asymptomatic, to symptomatic with varying levels of severity depending on age, comorbid conditions, and basal metabolic index. The aim of this study was to highlight associations between socio-demographic characteristics and comorbidities with persistent symptoms in COVID-19 survivors. This study is a retrospective study using de-identified data of 274 COVID-19 survivors. A thorough clinical history and physical assessment was conducted for all patients. Results indicate that: - the most common symptom manifested by survivors was easy fatigability. - neurologic symptoms were found in 39.1% of the COVID-19 survivors. Symptoms included headaches, insomnia, and attention deficits. - there was no significant association between demographic factors and comorbidities such as hypertension or diabetes and the presence of persistent symptoms in COVID-19 survivors. Authors conclude these findings, together with evidence from other studies, can guide policies and interventions aimed at improving the quality of life of survivors and return to usual health.
Abstract
BACKGROUND Coronavirus disease once thought to be a respiratory infection is now recognised as a multi-system disease affecting the respiratory, cardiovascular, gastrointestinal, neurological, immune, and hematopoietic systems. An emerging body of evidence suggests the persistence of COVID-19 symptoms of varying patterns among some survivors. This study aimed to describe persistent symptoms in COVID-19 survivors and investigate possible risk factors for these persistent symptoms. METHODS The study used a retrospective study design. The study population comprised of discharged COVID-19 patients. Demographic information, days since discharge, comorbidities, and persistent COVID-19 like symptoms were assessed in patients attending the COVID-19 outpatient clinic in Lagos State. Statistical analysis was done using STATA 15.0 software (StataCorp Texas) with significance placed at p-value < 0.05. RESULTS A total of 274 patients were enrolled in the study. A majority were within the age group > 35 to ≤49 years (38.3%), and male (66.1%). More than one-third (40.9%) had persistent COVID-19 symptoms after discharge, and 19.7% had more than three persistent COVID-like symptoms. The most persistent COVID-like symptoms experienced were easy fatigability (12.8%), headaches (12.8%), and chest pain (9.8%). Symptomatic COVID-19 disease with moderate severity compared to mild severity was a predictor of persistent COVID-like symptoms after discharge (p < 0.05). CONCLUSION Findings from this study suggests that patients who recovered from COVID-19 disease may still experience COVID-19 like symptoms, particularly fatigue and headaches. Therefore, careful monitoring should be in place after discharge to help mitigate the effects of these symptoms and improve the quality of life of COVID-19 survivors.
-
4.
Intake and adequacy of the vegan diet. A systematic review of the evidence.
Bakaloudi, DR, Halloran, A, Rippin, HL, Oikonomidou, AC, Dardavesis, TI, Williams, J, Wickramasinghe, K, Breda, J, Chourdakis, M
Clinical nutrition (Edinburgh, Scotland). 2021;40(5):3503-3521
-
-
-
-
Free full text
Plain language summary
This systematic review investigated vegan diets in the European populations and their adequacy of macro-and micronutrient intake, compared to the recommendations of the World Health Organization. Included were 48 studies and their outcomes regarding protein, carbohydrates, fats and micronutrients summarized. The overall results and their impact on health are discussed in the later sections of the paper. Adequate intake amongst vegans was seen with carbohydrates, fats, Vitamin A, B1, В6, C, E, iron, phosphorus, magnesium, copper and folate. Sodium exceeded recommended intake, whilst protein, Vitamin B2, B3, B12, D, iodine, zinc, calcium, potassium, selenium was of low consumption in a vegan diet. The bioavailability of some nutrients was also acknowledged. In summary, following a vegan diet appears to have positive and negative aspects. A vegan diet profile can contribute to disease prevention with lower incidence rates of obesity, Type 2 diabetes, and cardiovascular disease. Yet veganism appears to increase the risk for mental health conditions, bone fractures, immune system impairments, anaemias and deficiencies from low nutrient intake. This review yields a comprehensive overview of the positive and negative health consequences of a vegan diet. It may be a useful reference for those looking to support vegans or individuals considering adopting a vegan diet pattern.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Vegan diets in European populations tend to be lower in protein intake, particularly amino acids lysine, methionine and tryptophan.
- Other micronutrients that tend to lower in vegan diets are Vitamin B12, zinc, calcium and selenium.
- Healthcare practitioners should be aware of these potential deficiencies when working with vegan clients.
Evidence Category:
-
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
X
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
Vegan diets have become increasingly popular in the last ten years. This systematic review of 48 studies investigated the adequacy of vegan diets in European populations. It compared their macro- and micronutrient intakes compared to World Health Organization recommendations. It found that vegan diets tend to be lower in protein and in essential amino acids (lysine, methionine and tryptophan). They can also be lower in micronutrients especially vitamin B12, zinc, calcium and selenium. However, the lower intakes are not always associated with health impairments.
Clinical practice applications:
Practitioners should be aware of the potential deficiencies in a vegan diet.
Considerations for future research:
More research is needed to determine whether lower nutrient intakes in vegans correlated with poor health outcomes.
Abstract
BACKGROUND Vegan diets, where animal- and all their by-products are excluded from the diet, have gained popularity, especially in the last decade. However, the evaluation of this type of diet has not been well addressed in the scientific literature. This study aimed to investigate the adequacy of vegan diets in European populations and of their macro- and micronutrient intakes compared to World Health Organization recommendations. METHODS A systematic search in PubMed, Web of Science, IBSS, Cochrane library and Google Scholar was conducted and 48 studies (12 cohorts and 36 cross-sectional) were included. RESULTS Regarding macronutrients, vegan diets are lower in protein intake compared with all other diet types. Veganism is also associated with low intake of vitamins B2, Niacin (B3), B12, D, iodine, zinc, calcium, potassium, selenium. Vitamin B12 intake among vegans is significantly lower (0.24-0.49 μg, recommendations are 2.4 μg) and calcium intake in the majority of vegans was below recommendations (750 mg/d). No significant differences in fat intake were observed. Vegan diets are not related to deficiencies in vitamins A, B1, Β6, C, E, iron, phosphorus, magnesium, copper and folate and have a low glycemic load. CONCLUSIONS Following a vegan diet may result in deficiencies in micronutrients (vitamin B12, zinc, calcium and selenium) which should not be disregarded. However, low micro- and macronutrient intakes are not always associated with health impairments. Individuals who consume a vegan diet should be aware of the risk of potential dietary deficiencies.
-
5.
Vegan Diet Health Benefits in Metabolic Syndrome.
Marrone, G, Guerriero, C, Palazzetti, D, Lido, P, Marolla, A, Di Daniele, F, Noce, A
Nutrients. 2021;13(3)
-
-
-
Free full text
Plain language summary
Plant-based diets (PBD) have grown in popularity in recent years and have been associated with better health outcomes especially with heart disease, however poorly planned PBD’s can result in nutrient deficiencies like vitamin B12. This review aimed to summarise the health benefits of PBD’s, especially vegan diets, compared to omnivorous diets when looking at risk factors associated with heart disease. The authors started by summarising three PBD’s obvious in the literature; vegan diet with no animal products, lacto-ovo-vegetarian (LOV) with dairy products and eggs, and fish-vegetarian including fish and seafoods. The study then highlighted the strengths and weaknesses of the vegan diet, highlighting that although the vegan diet represents a healthy way of eating rich in carbohydrates, omega-6 fats, fibre, vitamin C, vitamin E and magnesium it can be low in protein, omega-3 fats, vitamin B12, vitamin D, calcium, iron, zinc and iodine if not properly planned. Heart disease incidence was reported to be lower in individuals on a PBD, especially vegans, when compared to omnivorous diets possibly due to their improvement on risk factors associated with the disease. Metabolic syndrome, blood pressure, fat production, and blood sugar balance were all shown to be improved and reasons such as their high fibre content reducing energy intake and causing feelings of satiety and their low saturated fat content impacting cholesterol production were listed as possible mechanisms behind the improvements. It was concluded that a nutritionist led, vegan diet can improve risk factors for heart disease resulting in better health outcomes. This study could be used by healthcare practitioners to understand where vegan diets may lack certain nutrients and the Importance of a well-planned vegan diet in the prevention of heart disease in those at an increased risk.
Abstract
Plant-based diets (PBDs) are increasingly consumed by the Italian population and around the world. In particular, among PBDs, the vegan diet is a food pattern characterized by the exclusion of all animal-origin foods. What drives people to adopt this model are mainly ethical, health and environmental reasons. A vegan diet, if well-balanced and varied, can help in achieving and maintaining an optimal state of health. However, this nutritional approach, if not well-balanced, can cause deficiencies in proteins, ω-3 fatty acids, iron, vitamin D and calcium, zinc, iodine and, above all, vitamin B12. Oral food supplements especially fortified foods are recommended in these cases to restore the nutritional deficiencies. A vegan diet generally reduces the risk of developing chronic non-communicable degenerative diseases, such as metabolic syndrome (MetS) and, in addition, requires fewer natural resources for food production than an omnivorous diet. The aim of this review is to analyze the possible impact of the vegan diet on MetS onset and its treatment.
-
6.
Improvement in Gastrointestinal Quality of Life Index (GIQLI) following meditation: An open-trial pilot study in India.
Kanchibhotla, D, Sharma, P, Subramanian, S
Journal of Ayurveda and integrative medicine. 2021;12(1):107-111
-
-
-
Free full text
Plain language summary
Gut health is a complex phenomenon, consisting of micro and macro integrity of various gastrointestinal organs from oesophagus to the rectum, allowing us to eat and digest without discomfort. The aim of this study was to investigate the improvement in gut health and gastrointestinal quality of life with the regular practice of a novel meditation called the Vaishvanara Agni meditation (VAM). This study was an open-trial single-arm, pre-post pilot study. Of all the 80 participants enrolled for the study, 54 participants completed the assessments at all three time points, and were considered for data analysis. Results indicate an overall improvement in the quality of life with regular practice of Vaishvanara Agni meditation. In fact, regular practice of VAM not only improved the physical strength and digestion of the individual, but also contributed to their mental, emotional and social health. Authors conclude that meditation practices which focus on improving digestion can be an effective tool for improving gut health.
Abstract
BACKGROUND Medical science is increasingly recognizing the role of gut health in achieving optimal wellbeing. A healthy gut improves digestion. Additionally, it has a positive impact on multiple physiological networks such as immune system, central nervous system and hepato-endocrine system, thus contributing to the overall quality of life. Functional gastrointestinal disorders: also known as disorders of gut-brain interaction, such as irritable bowel syndrome are increasing worldwide. Conditions like stress, anxiety and mental disorders are correlated with these disorders. Mind-body interventions have been shown to ameliorate stress, anxiety and related conditions that may aggravate functional gastrointestinal disorders. OBJECTIVE The present study aims to investigate the benefits of a novel meditation technique called the Vaishvanara Agni meditation (VAM) on the gastrointestinal quality of life. MATERIALS AND METHODS 54 subjects participated in the study and practiced VAM for 50 days. During the Vaishvanara Agni meditation (VAM), attention is directed to the navel region and the digestive system. The effect of the meditation was evaluated using the gastrointestinal quality of life (GI-QoL) questionnaire, which was administered to subjects at three different time points i.e. day 0, day 24 and day 50. RESULTS GI-QoL was significantly improved with the practice of VAM. Additionally, significant improvements were noticed in all sub domains especially core symptoms, physical strength and the psychological domain. CONCLUSION Meditation practices that focus on improving digestion can be an effective tool for improving gut health.
-
7.
Association of prior metabolic and bariatric surgery with severity of coronavirus disease 2019 (COVID-19) in patients with obesity.
Aminian, A, Fathalizadeh, A, Tu, C, Butsch, WS, Pantalone, KM, Griebeler, ML, Kashyap, SR, Rosenthal, RJ, Burguera, B, Nissen, SE
Surgery for obesity and related diseases : official journal of the American Society for Bariatric Surgery. 2021;17(1):208-214
-
-
-
Free full text
-
Plain language summary
A growing body of evidence indicates that patients with obesity are disproportionately affected with a severe form of SARS-CoV-2 infection and may experience resultant higher mortality. The aim of this study was to determine the association of prior metabolic surgery with severity of SARSCoV-2 infection in patients with severe obesity. This study is a retrospective, matched-cohort analysis of a prospective, observational, institutional review board–approved clinical registry of all patients tested for SARS-CoV-2 infection. The study population included a total of 363 patients, including 33 individuals who had metabolic surgery and 330 matched patients who tested positive. Results indicate that a history of metabolic surgery is associated with lower severity of SARSCoV-2 infection in patients with severe obesity, as manifested by lower risks of hospital and ICU admission. Authors conclude that prior metabolic surgery with subsequent weight loss and improvement of metabolic abnormalities could potentially reduce morbidity from SARS-CoV-2 infection.
Abstract
BACKGROUND Obesity is a risk factor for poor clinical outcomes in patients with coronavirus disease 2019 (COVID-19). OBJECTIVES To investigate the relationship between prior metabolic surgery and the severity of COVID-19 in patients with severe obesity. SETTING Cleveland Clinic Health System in the United States. METHODS Among 4365 patients who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) between March 8, 2020 and July 22, 2020 in the Cleveland Clinic Health System, 33 patients were identified who had a prior history of metabolic surgery. The surgical patients were propensity matched 1:10 to nonsurgical patients to assemble a cohort of control patients (n = 330) with a body mass index (BMI) ≥ 40 kg/m2 at the time of SARS-CoV-2 testing. The primary endpoint was the rate of hospital admission. The exploratory endpoints included admission to the intensive care unit (ICU), need for mechanical ventilation and dialysis during index hospitalization, and mortality. After propensity score matching, outcomes were compared in univariate and multivariate regression models. RESULTS The average BMI of the surgical group was 49.1 ± 8.8 kg/m2 before metabolic surgery and was down to 37.2 ± 7.1 at the time of SARS-CoV-2 testing, compared with the control group's BMI of 46.7 ± 6.4 kg/m2. In the univariate analysis, 6 (18.2%) patients in the metabolic surgery group and 139 (42.1%) patients in the control group were admitted to the hospital (P = .013). In the multivariate analysis, a prior history of metabolic surgery was associated with a lower hospital admission rate compared with control patients with obesity (odds ratio, 0.31; 95% confidence interval, 0.11-0.88; P = .028). While none of the 4 exploratory outcomes occurred in the metabolic surgery group, 43 (13.0%) patients in the control group required ICU admission (P = .021), 22 (6.7%) required mechanical ventilation, 5 (1.5%) required dialysis, and 8 (2.4%) patients died. CONCLUSION Prior metabolic surgery with subsequent weight loss and improvement of metabolic abnormalities was associated with lower rates of hospital and ICU admission in patients with obesity who became infected with SARS-CoV-2. Confirmation of these findings will require larger studies.
-
8.
Effectiveness of Health Coaching in Diabetes Control and Lifestyle Improvement: A Randomized-Controlled Trial.
Lin, CL, Huang, LC, Chang, YT, Chen, RY, Yang, SH
Nutrients. 2021;13(11)
-
-
-
Free full text
Plain language summary
World Health Organization statistics indicate that over 400 million people worldwide have Type 2 Diabetes. Health coaching is an approach to diabetes management that empowers patients to make healthier choices by changing their behaviours. This two-arm randomised controlled trial evaluated the effectiveness of health coaching in reducing blood sugar levels and following a healthy diet among Type 2 diabetic patients. Patients with diabetes improved their HbA1c by 0.62% after six months of health coaching. Through health coaching, patients were also able to reduce their calorie intake significantly by reducing their consumption of whole grains, meat, proteins, fats and oils and increasing their intake of vegetables. In the intervention group, diet modifications were also associated with a decrease in HbA1c. The benefits of health coaching in Type 2 diabetes management needs to be confirmed in more robust studies. However, healthcare professionals can use the results of this study to understand how behaviour change in diabetic patients contributes to blood sugar management and healthy eating.
Abstract
BACKGROUND The study aimed to look into the effectiveness of a 6-month health coaching intervention for HbA1c and healthy diet in the treatment of patients with type 2 diabetes. METHODS The study was carried out via a two-armed, randomized controlled trial that included 114 diabetic patients at a medical center in Taiwan. During the 6-month period, the intervention group had health coaching and usual care for 6 months, and the control group had usual care only. The outcome variables were HbA1c level and healthy diet for follow-up measurement in the third and sixth month. RESULTS The study discovered a significant decrease in HbA1c and health diet improvement after the 6-month health coaching. Patients in the intervention group decreased their daily intake of whole grains, fruits, meats and protein, and fats and oils while increasing their vegetables intake. CONCLUSIONS Health coaching may be conducive to the blood sugar control and healthy diet of patients with type 2 diabetes. Further study on health coaching with higher-quality evidence is needed.
-
9.
Efficacy and safety of low and very low carbohydrate diets for type 2 diabetes remission: systematic review and meta-analysis of published and unpublished randomized trial data.
Goldenberg, JZ, Day, A, Brinkworth, GD, Sato, J, Yamada, S, Jönsson, T, Beardsley, J, Johnson, JA, Thabane, L, Johnston, BC
BMJ (Clinical research ed.). 2021;372:m4743
-
-
-
-
Free full text
Plain language summary
Diet modification has long been recognised as a component for the treatment of diabetes. Diets low in carbohydrates have been extensively researched, as a diet for those with Type 2 Diabetes (T2D). This systematic review and meta-analysis aimed to determine the effect of low carbohydrate diets on T2D. The systematic review found 23 studies, including 1357 individuals, investigating the role of low carbohydrate diets on T2D outcomes. Low carbohydrate diet was defined as less than 130g of carbohydrate (less than 26% of calories from carbohydrate) for at least 12 weeks. Results reported at 6 months, found low carbohydrate diets were more effective than a normal diet at achieving diabetes remission. However, this effect diminished at 12 months, although longer term improvements were seen in blood lipids, weight loss and measures of prediabetes. It was concluded that individuals with T2D, eating a low carbohydrate diet for 6 months may reverse the disease. This study could be used by healthcare professionals to recommend a short-term low carbohydrate diet to individuals with T2D, to improve their chance of going into remission.
Expert Review
Conflicts of interest:
None
Take Home Message:
- Type 2 diabetes remains a significant and worsening problem worldwide, despite many pharmaceutical developments and a global emphasis on glycemic control.
- This review highlights structured LCDs as a worthwhile option for the management and treatment of diabetes, providing an opportunity for Nutritional Therapy Practitioners to support clients in adopting evidence-informed, modifiable dietary and lifestyle changes for Type Two Diabetes.
Evidence Category:
-
A: Meta-analyses, position-stands, randomized-controlled trials (RCTs)
-
X
B: Systematic reviews including RCTs of limited number
-
C: Non-randomized trials, observational studies, narrative reviews
-
D: Case-reports, evidence-based clinical findings
-
E: Opinion piece, other
Summary Review:
- Type 2 diabetes is the most common form of diabetes, accounting for 90-95% of cases.
- Previous randomised trials assessed low carbohydrate diets (LCDs) (<26-45% of daily calories from carbohydrate) as encouraging to improve blood glucose control and outcomes of type 2 diabetes but did not systematically assessed remission of diabetes using low carbohydrate diets (LCDs) and very low carbohydrate diets (VLCDs) for people with type 2 diabetes.
- Systematic reviews (SR) and meta-analyses represent the most valuable, reliable, and objective tool to summarise evidence from primary studies.
- This SR assessed 23 randomised controlled trials comparing LCDs with mostly low fat control diets in individuals / subjects / participants with type 2 diabetes. LCDs were defined as diets with less than 130 g/day or less than 26% of calories from carbohydrates, based on 2000 kcal/day. The authors used the Cochrane Risk of Bias tool 2.0 (RoB 2) to assess methodological quality of evidence, GRADE to assess the certainty of evidence
- On the basis of assessment of moderate to low certainty evidence, individuals / subjects / participants adhering to a LCD for six months may experience remission of type 2 diabetes without adverse consequences.
- Primary outcomes of interest were remission of type 2 diabetes (dichotomously defined as HbA1c <6.5% or fasting glucose <7.0 mmol/L), with or without the use of diabetes medication.
- Eight studies reported on remission of diabetes at six months. Pooled analysis showed that when remission was defined by an HbA1c level below 6.5% independent of medication use, LCDs increased remissions by an additional 32 per 100 patients followed (risk difference 0.32, 95% confidence interval 0.17 to 0.47; 8 studies, n=264; GRADE=moderate)
- When remission was defined by an HbA1c level below 6.5% and the absence of diabetes medication, LCDs increased remissions at a lower rate (risk difference 0.05, –0.05 to 0.14; 5 studies, n=199; GRADE=low)
- Additional primary outcomes were weight loss, HbA1c:
- 18 studies reported on Weight loss results (mean difference –3.46, 95% confidence interval –5.25 to –1.67; n=882 (note that positive results not sustained at 12 mo)
- Seventeen studies reported on HbA1c levels at six months, LCDs achieved greater reductions in HbA1c than did control diets (mean difference –0.47%, –0.60 to –0.34; n=747
- Limitations of study: 1) the definition of remission of diabetes, 2) Self-reported dietary intake data are prone to measurement error, particularly in dietary trials in which participants are not blinded
- This SR was funded in part by Texas A&M University.
- The authors declared no conflicts of interest.
Clinical practice applications:
The Authors highlight LCD diets incorporating carbohydrate of less than 130 g/day or less than 26% of calories (based on 2000 kcal/day) may be a safe strategy to help individuals with type 2 diabetes achieve weight loss and better blood glucose control over a six-month period. Results may not be sustained at 12 months.
Considerations for future research:
- The definition of diabetes remission needs clarification, especially with regard to threshold concentrations of Hb1Ac or fasting glucose and the use of diabetes medication.
- Safety concerns have been raised with LCDs. Although no significant or clinically important increase in total or serious adverse events was identified in this SR, these outcomes should be reported in future trials to confirm the certainty of evidence for safety.
- The Authors suggest long term, well designed, calorie controlled randomised trials are needed to determine the effects of LCD on sustained weight loss and remission of diabetes.
- Larger treatment effects for LCDs in shorter term trials (3 to <6 months), may be trialed as an effect modifier
Abstract
OBJECTIVE To determine the efficacy and safety of low carbohydrate diets (LCDs) and very low carbohydrate diets (VLCDs) for people with type 2 diabetes. DESIGN Systematic review and meta-analysis. DATA SOURCES Searches of CENTRAL, Medline, Embase, CINAHL, CAB, and grey literature sources from inception to 25 August 2020. STUDY SELECTION Randomized clinical trials evaluating LCDs (<130 g/day or <26% of a 2000 kcal/day diet) and VLCDs (<10% calories from carbohydrates) for at least 12 weeks in adults with type 2 diabetes were eligible. DATA EXTRACTION Primary outcomes were remission of diabetes (HbA1c <6.5% or fasting glucose <7.0 mmol/L, with or without the use of diabetes medication), weight loss, HbA1c, fasting glucose, and adverse events. Secondary outcomes included health related quality of life and biochemical laboratory data. All articles and outcomes were independently screened, extracted, and assessed for risk of bias and GRADE certainty of evidence at six and 12 month follow-up. Risk estimates and 95% confidence intervals were calculated using random effects meta-analysis. Outcomes were assessed according to a priori determined minimal important differences to determine clinical importance, and heterogeneity was investigated on the basis of risk of bias and seven a priori subgroups. Any subgroup effects with a statistically significant test of interaction were subjected to a five point credibility checklist. RESULTS Searches identified 14 759 citations yielding 23 trials (1357 participants), and 40.6% of outcomes were judged to be at low risk of bias. At six months, compared with control diets, LCDs achieved higher rates of diabetes remission (defined as HbA1c <6.5%) (76/133 (57%) v 41/131 (31%); risk difference 0.32, 95% confidence interval 0.17 to 0.47; 8 studies, n=264, I2=58%). Conversely, smaller, non-significant effect sizes occurred when a remission definition of HbA1c <6.5% without medication was used. Subgroup assessments determined as meeting credibility criteria indicated that remission with LCDs markedly decreased in studies that included patients using insulin. At 12 months, data on remission were sparse, ranging from a small effect to a trivial increased risk of diabetes. Large clinically important improvements were seen in weight loss, triglycerides, and insulin sensitivity at six months, which diminished at 12 months. On the basis of subgroup assessments deemed credible, VLCDs were less effective than less restrictive LCDs for weight loss at six months. However, this effect was explained by diet adherence. That is, among highly adherent patients on VLCDs, a clinically important reduction in weight was seen compared with studies with less adherent patients on VLCDs. Participants experienced no significant difference in quality of life at six months but did experience clinically important, but not statistically significant, worsening of quality of life and low density lipoprotein cholesterol at 12 months. Otherwise, no significant or clinically important between group differences were found in terms of adverse events or blood lipids at six and 12 months. CONCLUSIONS On the basis of moderate to low certainty evidence, patients adhering to an LCD for six months may experience remission of diabetes without adverse consequences. Limitations include continued debate around what constitutes remission of diabetes, as well as the efficacy, safety, and dietary satisfaction of longer term LCDs. SYSTEMATIC REVIEW REGISTRATION PROSPERO CRD42020161795.
-
10.
The Role of Diet Quality in Mediating the Association between Ultra-Processed Food Intake, Obesity and Health-Related Outcomes: A Review of Prospective Cohort Studies.
Dicken, SJ, Batterham, RL
Nutrients. 2021;14(1)
-
-
-
Free full text
Plain language summary
Diet has long been a cornerstone of weight management, with dietary policies being a core feature of government and health organisation strategies to reduce obesity worldwide. Indeed, poor diets are a leading cause of preventable obesity-related death and non-communicable diseases, including cancer, cardiovascular disease and type 2 diabetes. The aim of this study was to provide novel insights into the relative impact of nutrient content and dietary patterns vs. ultra-processing on obesity and adverse health-related outcomes. This study is a review of prospective cohort studies. Findings show that adjustment for fat, sugar and sodium intake, or adjustment for adherence to a range of healthy or unhealthy dietary patterns has a minimal impact on the adverse associations between UPF intake and a diverse range of health-related outcomes. Authors conclude that their findings raise important questions regarding current policy and future research needs, suggesting that the nature and extent of processing is an important dietary dimension.
Abstract
Prospective cohort studies show that higher intakes of ultra-processed food (UPF) increase the risk of obesity and obesity-related outcomes, including cardiovascular disease, cancer and type 2 diabetes. Whether ultra-processing itself is detrimental, or whether UPFs just have a lower nutritional quality, is debated. Higher UPF intakes are inversely associated with fruit, vegetables, legumes and seafood consumption. Therefore, the association between UPFs and poor health could simply be from excess nutrient intake or from a less healthful dietary pattern. If so, adjustment for dietary quality or pattern should explain or greatly reduce the size of the significant associations between UPFs and health-related outcomes. Here, we provide an overview of the literature and by using a novel approach, review the relative impact of adjusting for diet quality/patterns on the reported associations between UPF intake and health-related outcomes in prospective cohort studies. We find that the majority of the associations between UPFs, obesity and health-related outcomes remain significant and unchanged in magnitude after adjustment for diet quality or pattern. Our findings suggest that the adverse consequences of UPFs are independent of dietary quality or pattern, questioning the utility of reformulation to mitigate against the obesity pandemic and wider negative health outcomes of UPFs.