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Unhealthy Food and Beverage Consumption in Children and Risk of Overweight and Obesity: A Systematic Review and Meta-analysis.
Rousham, EK, Goudet, S, Markey, O, Griffiths, P, Boxer, B, Carroll, C, Petherick, ES, Pradeilles, R
Advances in nutrition (Bethesda, Md.). 2022
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Infants and children are consuming increasing amounts of foods with added sugars, high in salt, and high in saturated or trans fats. Commercially prepared foods are more likely to be high in energy, low in nutrients (energy dense, nutrient-poor), and ultra-processed. The aim of this study was to examine, in children aged ≤10.9 y, the risks of greater consumption of unhealthy foods and beverages compared with no or low consumption on overweight and obesity. This study is a systematic review and meta-analysis which included the summarized characterises of 71 articles from 60 included studies. Results indicate that in children aged ≤10.9 years, consumption of sugar-sweetened beverages and unhealthy foods may increase body mass index, percentage body fat, or the odds of overweight/obesity (low to very-low certainty). Furthermore, there was little or no difference to body mass index, percentage body fat, or overweight/obesity outcomes (low certainty) after consumption of artificially sweetened beverages and 100% fruit juices. Authors conclude that policy recommendations are needed to address the growing burden of overweight and obesity that children are experiencing worldwide.
Abstract
This WHO-commissioned review contributed to the update of complementary feeding recommendations, synthesizing evidence on effects of unhealthy food and beverage consumption in children on overweight and obesity. We searched PubMed (Medline), Cochrane CENTRAL and Embase for articles, irrespective of language or geography. Inclusion criteria were: 1) randomized controlled trials (RCTs); non-RCTs; cohort studies and pre/post studies with control; 2) participants ≤ 10.9 y at exposure; 3) studies reporting greater consumption of unhealthy foods/beverages vs. no or low consumption; 4) studies assessing anthropometric and/or body composition; and 5) publication date ≥ 1971. Unhealthy foods and beverages were defined using nutrient- and food-based approaches. Risk of bias was assessed using the ROBINS-I and RoB2 tools for non-randomized and randomized studies, respectively. Narrative synthesis was complemented by meta-analyses where appropriate. Certainty of evidence was assessed using GRADE. Of 26,542 identified citations, 60 studies from 71 articles were included. Most studies were observational (59/60), and no included studies were from low-income countries. The evidence base was low quality, as assessed by ROBINS-I and RoB2 tools. Evidence synthesis was limited by the different interventions and comparators across studies. Evidence indicated that consumption of sugar-sweetened beverages (SSB) and unhealthy foods in childhood may increase body mass index (BMI)/BMI z-score, % body fat or odds of overweight/obesity (low certainty of evidence). Artificially-sweetened beverages and 100% fruit juice consumption may make little/no difference to BMI, % body fat or overweight/obesity outcomes (low certainty of evidence). Meta-analyses of a subset of studies indicated a positive association between SSB intake and % body fat, but no association with change in BMI and BMI z-score. High-quality epidemiological studies that are designed to assess the effects of unhealthy food consumption during childhood on risk of overweight/obesity are needed to contribute to a more robust evidence base upon which to design policy recommendations. This protocol was registered at https://www.crd.york.ac.uk/PROSPERO as CRD42020218109.
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Overweight and obesity as risk factors for COVID-19-associated hospitalisations and death: systematic review and meta-analysis.
Sawadogo, W, Tsegaye, M, Gizaw, A, Adera, T
BMJ nutrition, prevention & health. 2022;5(1):10-18
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A novel coronavirus named SARS-CoV-2, causing COVID-19, emerged in late 2019. The prognosis of COVID-19 has been consistently reported to worsen with older age, male sex and comorbidities. The aim of this study was to quantify the association between overweight or obesity and COVID-19-related hospitalisations and death, and to assess the magnitude of the association and the potential dose–response relationships. This study is a systematic review and meta-analysis of 208 studies. A total of 3 550 977 participants from over 32 countries were included in this study. Results indicate that being overweight increases the risk of COVID-19-related hospitalisations but not death while obesity and extreme obesity increase the risk of both COVID-19-related hospitalisations and death. In addition, there was a linear dose–response association between obesity categories and COVID-19 outcomes. However, the strength of the association has weakened over time following the pattern of the first wave of COVID-19. Authors conclude that their findings suggest the importance of increased vigilance towards people with excess adiposity. Some preventative measures for this vulnerable group include prompt access to COVID-19 testing and healthcare, as well as prioritisation for COVID-19 vaccination.
Abstract
Objective: To quantify the current weight of evidence of the association between overweight and obesity as risk factors for COVID-19-related hospitalisations (including hospital admission, intensive care unit admission, invasive mechanical ventilation) and death, and to assess the magnitude of the association and the potential dose-response relationships. Design: PubMed, Embase, Cochrane, Web of Sciences, WHO COVID-19 database and Google Scholar were used to identify articles published up to 20 July 2021. Peer-reviewed studies reporting adjusted estimates of the association between overweight or obesity and COVID-19 outcomes were included. Three authors reviewed the articles and agreed. The quality of eligible studies was assessed using the Newcastle-Ottawa Quality Assessment Scale. Random-effects meta-analysis was used to estimate the combined effects. Results: A total of 208 studies with 3 550 997 participants from over 32 countries were included in this meta-analysis. Being overweight was associated with an increased risk of COVID-19-related hospitalisations (OR 1.19, 95% CI 1.12 to 1.28, n=21 studies), but not death (OR 1.02, 95% CI 0.92 to 1.13, n=21). However, patients with obesity were at increased risk of both COVID-19-related hospitalisations (OR 1.72, 95% CI 1.62 to 1.84, n=58) and death (OR 1.25, 95% CI 1.19 to 1.32, n=77). Similarly, patients with extreme obesity were at increased risk of COVID-19-related hospitalisations (OR 2.53, 95% CI 1.67 to 3.84, n=12) and death (OR 2.06, 95% CI 1.76 to 3.00, n=19). There was a linear dose-response relationship between these obesity categories and COVID-19 outcomes, but the strength of the association has decreased over time. Conclusion: Being overweight increases the risk of COVID-19-related hospitalisations but not death, while obesity and extreme obesity increase the risk of both COVID-19-related hospitalisations and death. These findings suggest that prompt access to COVID-19 care, prioritisation for COVID-19 vaccination and other preventive measures are warranted for this vulnerable group.
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Effectiveness of Therapeutic Patient Education Interventions in Obesity and Diabetes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
Correia, JC, Waqas, A, Huat, TS, Gariani, K, Jornayvaz, FR, Golay, A, Pataky, Z
Nutrients. 2022;14(18)
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Obesity and diabetes mellitus (DM) account for the highest burden of non-communicable diseases. Obesity is also highly comorbid with type 2 DM with a prevalence of 8.5% among adults around the globe. The aims of this study were to present (a) a critical synthesis of the theoretical basis and development of therapeutic patient education (TPE) interventions for obesity and diabetes, and (b) quantitative evidence for the efficacy of these interventions across a range of biomedical, psychosocial and psychological outcomes. This study is a systematic review and meta-analysis of fifty-four randomised controlled trials. Results show that: - TPE interventions bring about significant improvements in biomedical outcomes among patients with DM and obesity. - there weren’t significant differences in the quality of life of participants undergoing TPE interventions (inconclusive as only data from two studies were considered). - interventions delivered through different media and delivery formats may be equally effective. Authors conclude that the use of electronic media such as short messaging services, website-based educational programs and animation media can be used to deliver TPE effectively.
Abstract
Diabetes mellitus (DM) and obesity account for the highest burden of non-communicable diseases. There is increasing evidence showing therapeutic patient education (TPE) as a clinically and cost-effective solution to improve biomedical and psychosocial outcomes among people with DM and obesity. The present systematic review and meta-analysis present a critical synthesis of the development of TPE interventions for DM and obesity and the efficacy of these interventions across a range of biomedical, psychosocial and psychological outcomes. A total of 54 of these RCTs were identified among patients with obesity and diabetes and were thus qualitatively synthesized. Out of these, 47 were included in the quantitative synthesis. There was substantial heterogeneity in the reporting of these outcomes (I2 = 88.35%, Q = 317.64), with a significant improvement noted in serum HbA1c levels (standardized mean difference (SMD) = 0.272, 95% CI: 0.118 to 0.525, n = 7360) and body weight (SMD = 0.526, 95% CI: 0.205 to 0.846, n = 1082) in the intervention group. The effect sizes were comparable across interventions delivered by different modes and delivery agents. These interventions can be delivered by allied health staff, doctors or electronically as self-help programs, with similar effectiveness (p < 0.001). These interventions should be implemented in healthcare and community settings to improve the health outcomes in patients suffering from obesity and DM.
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The effects of olive leaf extract on cardiovascular risk factors in the general adult population: a systematic review and meta-analysis of randomized controlled trials.
Razmpoosh, E, Abdollahi, S, Mousavirad, M, Clark, CCT, Soltani, S
Diabetology & metabolic syndrome. 2022;14(1):151
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Modifiable unhealthy behaviours, such as sedentary lifestyle, smoking, and unhealthy food habits, are regarded as important contributors to the widespread prevalence of cardiovascular diseases (CVDs), which occur concurrently in overweight/obesity, hypertension, dyslipidaemia, hyperglycaemia, and inflammation. The aim of this study was to investigate whether olive leaf extract (OLE) could improve the major cardiovascular-related variables, including lipid profile, glucose haemostasis, blood pressure, as well as liver/kidney and inflammatory markers in the general adult population. This study is a systematic review and meta-analysis of twelve randomised controlled studies. Results show that OLE supplementation: - significantly decreased triglycerides and systolic blood pressure levels. - only had short-term positive effects on blood pressure and lipid profiles, which may be attributed to the active constituents in OLE. - had more profitable effects on the improvement of triglycerides, blood pressure, total cholesterol and low-density lipoprotein cholesterol measures among participants with hypertension and individuals with normal body weight. Authors conclude that stronger randomised controlled trial investigations, assessing different doses and durations of OLE, are required to better elucidate the effects of OLE supplementation.
Abstract
BACKGROUND The aim of this systematic review and meta-analysis was to determine the effect of olive leaf extract (OLE) supplementation on cardiovascular-related variables, including lipid, glycemic, inflammatory, liver and renal-related factors, as well as blood pressure. METHODS PubMed, ISI Web of Science, Scopus, and Cochrane library were searched, up to October 2021, for relevant controlled trials. Mean differences and standard deviations were pooled for all outcomes, using a random-effects model. The methodological quality, as well as quality of evidence were assessed using standard tools. RESULTS Twelve studies (n = 819 participants) were included in our analyses. Overall analyses showed that OLE supplementation significantly decreased triglyceride (TG) levels (WMD = - 9.51 mg/dl, 95% CI - 17.83, - 1.18; P = 0.025; I2 = 68.7%; P-heterogeneity = 0.004), and systolic blood pressure (SBP) (WMD = - 3.86 mmHg, 95% CI - 6.44, - 1.28 mmHg; P = 0.003; I2 = 19.9%; P-heterogeneity = 0.28). Subgroup analyses also revealed a significant improvement in SBP (- 4.81 mmHg) and diastolic blood pressure (- 2.45 mmHg), TG (- 14.42 mg/dl), total cholesterol (TC) (- 9.14 mg/dl), and low-density lipoprotein-C (LDL-C) (- 4.6 mg/dl) measurements, in patients with hypertension. Significant reductions were also observed in TC (- 6.69 mg/dl), TG (- 9.21 mg/dl), and SBP (- 7.05 mmHg) in normal-weight individuals. However, no meaningful changes were seen in glucose hemostasis, liver and kidney, or inflammatory markers. CONCLUSION The present study revealed that supplementation with OLE yielded beneficial effects for blood pressure and lipid profile in adults, especially in patients with hypertension. As the quality of evidence for glucose hemostasis variables, liver, kidney, and inflammatory markers, were low-to-very low, higher quality RCTs may impact the overarching results. This study was registered at PROSPERO with the code CRD42022302395.
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The Effect of Yoga on the Lipid Profile: A Systematic Review and Meta-Analysis of Randomized Clinical Trials.
Ghazvineh, D, Daneshvar, M, Basirat, V, Daneshzad, E
Frontiers in nutrition. 2022;9:942702
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Modernisation has brought increased comforts and limited mobility in our lives at the cost of an increased prevalence of hypertension, diabetes mellitus, dyslipidaemia, and obesity, which are predecessors of major cardiovascular diseases. Prevention and control of coronary heart disease and its associated diseases are essential and can be achieved by modifying the lipid profile. The aim of this study was to systematically assess the effects of yoga on blood lipid levels. This study is a systematic review and meta-analysis of fifty-three randomised controlled studies. All studies employed a parallel design with a total of 13,191 participants whom were divided into 6,700 individuals in the control group and 6,517 in the intervention group. Results show that yoga had decreased total cholesterol, low-density lipoprotein cholesterol, triglycerides, and very low-density lipoprotein cholesterol and increased high-density lipoprotein cholesterol among yoga practitioners. Authors conclude that yoga had a striking effect on balancing lipid profiles.
Abstract
OBJECTIVES Yoga is a mind-body stress-relieving exercise that increases mental and physical health, which may have a role in the improvement of metabolic disorders. The present study has reviewed the effect of yoga on lipid profiles as a systematic review and meta-analysis. METHODS We evaluated the available randomized controlled trials on the effects of yoga-based programs, and lipid profiles by searching PubMed/Medline, Scopus, Web of Science, and the Cochrane central register of control trials up to January 2022. Both fixed and random effect analyses were used to find the relationships. Subgroup analysis was performed based on the continent, duration of the included studies, gender, and health condition of participants to discover the sources of heterogeneity. RESULT Fifty-three studies were included in the current systematic review and meta-analysis with a total sample size of 13,191. There was a striking association between yoga and total cholesterol (-10.31 mg/dl; 95% CI: -14.16, -6.45; I 2 = 82.5%, P < 0.001), low-density lipoprotein cholesterol (-8.64 mg/dl; 95% CI: -12.03, -5.25; I 2 = 75.0%, P < 0.001), high-density lipoprotein cholesterol (1.98 mg/dl; 95% CI: 0.81, 3.14; I 2 = 91.6%, P < 0.001), triglycerides (-13.50 mg/dl; 95% CI: -20.09, -6.92; I 2 = 90.7%, P < 0.001) and very low-density lipoprotein (-3.94 mg/dl; 95%CI: -6.31, -1.56; I 2 = 72.2%, P < 0.001). CONCLUSION It seems yoga interventions had a substantial effect on lipid profiles, however, more qualified trials or cohort studies are needed to conclude exactly.
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Causal relationship between obesity, lifestyle factors and risk of benign prostatic hyperplasia: a univariable and multivariable Mendelian randomization study.
Wang, YB, Yang, L, Deng, YQ, Yan, SY, Luo, LS, Chen, P, Zeng, XT
Journal of translational medicine. 2022;20(1):495
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Benign prostatic hyperplasia (BPH) is a common benign disease in middle-aged and elderly men which is often underestimated and underdiagnosed. If patients are not treated in time, it may lead to serious complications, such as urinary retention, renal insufficiency and renal failure. The aim of this study was to evaluate the possible causal associations of abdominal obesity (measured as waist circumference), overall obesity (measured as body mass index), lifestyle factors (dietary habits, smoking, alcohol drinking, and sedentary behaviour) with risk of BPH. This study is a univariable and multivariable mendelian randomised study. Results show that genetic predisposition to higher waist circumference and sedentary behaviour are independently and causally associated with the risk of BPH. However, there isn’t conclusive evidence that genetic predisposition to relative carbohydrate, fat, protein, and sugar intake, smoking and alcohol drinking are causally associated with the risk of BPH. Authors conclude that further studies are needed to identify comprehensive risk factors on BPH and develop freely accessible prediction models for the BPH. These will help to identify individuals at particular risk and provide decision-making supports for individualised intervention.
Abstract
BACKGROUND Obesity (waist circumference, body mass index (BMI)) and lifestyle factors (dietary habits, smoking, alcohol drinking, Sedentary behavior) have been associated with risk of benign prostatic hyperplasia (BPH) in observational studies, but whether these associations are causal is unclear. METHODS We performed a univariable and multivariable Mendelian randomization study to evaluate these associations. Genetic instruments associated with exposures at the genome-wide significance level (P < 5 × 10-8) were selected from corresponding genome-wide associations studies (n = 216,590 to 1,232,091 individuals). Summary-level data for BPH were obtained from the UK Biobank (14,126 cases and 169,762 non-cases) and FinnGen consortium (13,118 cases and 72,799 non-cases). Results from UK Biobank and FinnGen consortium were combined using fixed-effect meta-analysis. RESULTS The combined odds ratios (ORs) of BPH were 1.24 (95% confidence interval (CI), 1.07-1.43, P = 0.0045), 1.08 (95% CI 1.01-1.17, P = 0.0175), 0.94 (95% CI 0.67-1.30, P = 0.6891), 1.29 (95% CI 0.88-1.89, P = 0.1922), 1.23 (95% CI 0.85-1.78, P = 0.2623), and 1.04 (95% CI 0.76-1.42, P = 0.8165) for one standard deviation (SD) increase in waist circumference, BMI, and relative carbohydrate, fat, protein and sugar intake, 1.05 (95% CI 0.92-1.20, P = 0.4581) for one SD increase in prevalence of smoking initiation, 1.10 (95% CI 0.96-1.26, P = 0.1725) and 0.84 (95% CI 0.69-1.02, P = 0.0741) for one SD increase of log-transformed smoking per day and drinks per week, and 1.31 (95% CI 1.08-1.58, P = 0.0051) for one SD increase in sedentary behavior. Genetically predicted waist circumference (OR = 1.26, 95% CI 1.11-1.43, P = 0.0004) and sedentary behavior (OR = 1.14, 95% CI 1.05-1.23, P = 0.0021) were associated with BPH after the adjustment of BMI. CONCLUSION This study supports independent causal roles of high waist circumference, BMI and sedentary behavior in BPH.
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Efficacy of cinnamon supplementation on glycolipid metabolism in T2DM diabetes: A meta-analysis and systematic review.
Zhou, Q, Lei, X, Fu, S, Li, Z, Chen, Y, Long, C, Li, S, Chen, Q
Frontiers in physiology. 2022;13:960580
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Diabetes mellitus (DM) is categorised into three main types: type 1 diabetes mellitus, type 2 diabetes mellitus (T2DM), and gestational diabetes mellitus. T2DM accounts for approximately 90% of diabetes mellitus cases. The aim of this study was to assess the effects of cinnamon on glucose and lipid levels in patients with T2DM. This study is a systematic review and meta-analysis of fifteen randomised controlled trials with a total of 1020 patients. Results show that blood glycolipid [a carbohydrate that is covalently linked to a lipid] levels were improved dramatically in diabetes patients who received cinnamon instead of a placebo. Cinnamon supplementation also exerted a favourable impact on metabolic (especially glucose, body mass index and lipids) abnormalities. Authors conclude that their findings show a beneficial impact on hypoglycaemia and lipids with cinnamon and cinnamon extract, implicating the extracts as therapeutic agents that might ameliorate hyperglycaemia in diabetes.
Abstract
Background: Cinnamon is a spice used in cooking and in large quantities as a medical complement with hypoglycemic and lipid-lowering properties. The potential pharmacological mechanisms underlying cinnamon's anti-diabetic properties and its active ingredients have not been adequately determined. The current meta-analysis aims to systematically review the potential pharmacological mechanisms underlying the hypoglycemic and hypolipidemic efficacy of cinnamon administration and summarize clinical recommendations of cinnamon and its active ingredients. Method: Relevant randomized clinical trials (RCTs) were identified through a literature search that spanned the years January 2005 to April 2022. Retrieve electronic databases including Web of Science, PubMed, Embase, Medline, and the Cochrane Library. To obtain standardized mean differences (SMDs), continuous outcomes were pooled and 95 percent confidence intervals (CIs) were provided. Categorical outcomes were aggregated to calculate relative risks (RRs) and were accompanied by 95% CIs. Heterogeneity was measured using the Cochrane Q-test and I2 statistics, with a p < 0.05 considered as substantial heterogeneity. If I2 was less than 50%, a fixed effect model was employed; otherwise, a random effect model was used. Subgroup analyses and sensitivity analyses were performed to identify the origins of heterogeneity. Publication bias was retrieved by means of a funnel-plot analysis and Egger's test. The data were analyzed using revman (V.5.3) and stata (V.15) software packages. Results: These 16 RCTs included a total of 1,020 patients who were followed for a duration ranging from 40 days to 4 months. According to the current meta-analysis results, glycolipid levels in diabetic individuals who received cinnamon were significantly improved as compared to those who got placebo (All p < 0.05). An adverse effect was only detected in one patient. Conclusion: These findings imply that cinnamon has a significant influence on lipid and glucose metabolism regulation. An even more pronounced effect was observed in patients with HbA1c of 8%. The results of this study suggested that cinnamon may be utilized as hypoglycemic and lipid-lowering supplement in clinical settings with a guaranteed safety profile.Systematic Review Registration: [PROSPERO], identifier [CRD42022322735].
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Dietary macronutrients and the gut microbiome: a precision nutrition approach to improve cardiometabolic health.
Jardon, KM, Canfora, EE, Goossens, GH, Blaak, EE
Gut. 2022;71(6):1214-1226
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The global rise in the prevalence of obesity is strongly associated with an increase in the incidence and prevalence of cardiometabolic diseases, including insulin resistance (IR) and type 2 diabetes mellitus. In recent years, advancements have been made in understanding the involvement of the gut microbiome in obesity and related cardiometabolic complications as regulator of host energy and substrate metabolism. This study is a review that discusses the latest research describing interactions between dietary composition, the gut microbiome and host metabolism. Results show that current evidence for developing optimal dietary interventions targeting bodyweight control and IR via the gut microbiota is still in its infancy and does not capture the complexity of the integration of a whole-diet approach, the microbial and the host’s metabolic phenotype. Furthermore, implementation of targeted, precision nutrition intervention strategies or dietary guidelines for individuals or subgroups in public health requires further insight in the mechanisms involved in (non-)response to dietary intervention. Authors conclude that future studies are needed and these should focus on assessing detailed individual phenotyping and gaining insight into the balance between carbohydrate and protein fermentation by the gut microbiota as well as the site of fermentation in the colon.
Abstract
Accumulating evidence indicates that the gut microbiome is an important regulator of body weight, glucose and lipid metabolism, and inflammatory processes, and may thereby play a key role in the aetiology of obesity, insulin resistance and type 2 diabetes. Interindividual responsiveness to specific dietary interventions may be partially determined by differences in baseline gut microbiota composition and functionality between individuals with distinct metabolic phenotypes. However, the relationship between an individual's diet, gut microbiome and host metabolic phenotype is multidirectional and complex, yielding a challenge for practical implementation of targeted dietary guidelines. In this review, we discuss the latest research describing interactions between dietary composition, the gut microbiome and host metabolism. Furthermore, we describe how this knowledge can be integrated to develop precision-based nutritional strategies to improve bodyweight control and metabolic health in humans. Specifically, we will address that (1) insight in the role of the baseline gut microbial and metabolic phenotype in dietary intervention response may provide leads for precision-based nutritional strategies; that (2) the balance between carbohydrate and protein fermentation by the gut microbiota, as well as the site of fermentation in the colon, seems important determinants of host metabolism; and that (3) 'big data', including multiple omics and advanced modelling, are of undeniable importance in predicting (non-)response to dietary interventions. Clearly, detailed metabolic and microbial phenotyping in humans is necessary to better understand the link between diet, the gut microbiome and host metabolism, which is required to develop targeted dietary strategies and guidelines for different subgroups of the population.
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Dose-response relationship between weight loss and improvements in obstructive sleep apnea severity after a diet/lifestyle interventions: secondary analyses of the "MIMOSA" randomized clinical trial.
Georgoulis, M, Yiannakouris, N, Kechribari, I, Lamprou, K, Perraki, E, Vagiakis, E, Kontogianni, MD
Journal of clinical sleep medicine : JCSM : official publication of the American Academy of Sleep Medicine. 2022;18(5):1251-1261
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Obstructive sleep apnoea (OSA) represents one of the most common and serious sleep-related breathing disorders. Excess body weight has emerged as the strongest modifiable predictor of the onset and severity of OSA. The aim of this study was to explore the dose-response relationship between the degree of weight loss and improvements in OSA severity. This study is a secondary analysis of the Mediterranean diet/lifestyle Intervention for the Management of Obstructive Sleep Apnea (MIMOSA) study, which was designed as a single-centre, single-blind, parallel, randomised, controlled clinical trial. Results show that respiratory events and oximetry indices improved only in patients who lost weight and improvements were proportional to the degree of weight loss. Authors conclude that their findings indicate a dose-response relationship between the degree of weight loss and improvement in OSA severity and symptoms. However, further research is needed to gather more data on the optimal degree of weight loss and appropriate weight-loss interventions for managing the wide spectrum of OSA severity to guide clinical practice.
Expert Review
Conflicts of interest:
None
Take Home Message:
Important from a public health perspective:
- This study has confirmed that even a small degree of weight loss can have a beneficial effect on respiratory events and oxygen desaturation in moderate-to-severe OSA, but clinicians should preferably aim at a ≥ 5% weight loss, and ideally a ≥ 10% weight loss, to achieve clinically meaningful reductions in OSA severity.
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
OSA represents one of the most common and serious sleep-related breathing disorders, with a high worldwide prevalence of almost 1 billion people. OSA has numerous well-established cardiometabolic consequences.
The authors highlight that weight loss is essential for obstructive sleep apnea (OSA) management. However, the optimal degree of weight loss for improving OSA severity or eliminating sleep-disordered breathing has not been extensively studied. The aim of this study was to explore the dose-response relationship between the degree of weight loss and improvements in OSA severity.
Methods
This is a secondary analysis of the Mediterranean diet/lifestyle Intervention for the Management of Obstructive Sleep Apnea (MIMOSA) study. This study was designed as a single-center, single-blind, parallel, randomised, controlled clinical trial to evaluate the effectiveness of a weight-loss Mediterranean dietary/lifestyle intervention on managing OSA.
This 6-month long clinical trial included 180 adult, overweight/obese moderate-to-severe OSA patients (45 patients per study group plus a 29% dropout rate). All patients were prescribed the standard of care continuous positive airway pressure (CPAP) therapy and were randomised to 3 arms: standard care; Mediterranean diet; Mediterranean lifestyle
Based on percent change in weight at 6 months, participants were categorised into a weight-stable/gain (WS/GG) group or one of 3 weight-loss groups (WLG): < 5%WLG; 5%–10%WLG; ≥ 10%WLG. Polysomnographic data and OSA symptoms were also evaluated preintervention and postintervention.
Results
Results confirm a dose-response relationship between the degree of weight loss achieved through a dietary/lifestyle intervention and improvements in OSA severity.
- Respiratory events and oximetry indices improved only in patients who lost weight. Improvements were proportional to the degree of weight loss.
- Median percent change in apnea-hypopnea index (AHI) was −11.7%, − 37.9%, and − 49.3% in the < 5%WLG, 5%–10%WLG, and ≥ 10%WLG, respectively (P < .001).
- Compared to the WS/GG, the age-, sex-, baseline-, and CPAP use–adjusted relative risk (95% confidence interval) of severe OSA (AHI ≥ 30 events/h) was 0.45 (0.23–0.87) in the 5%–10%WLG and 0.32 (0.17–0.64) in the ≥ 10%WLG; the risk was also lower in the ≥ 10%WLG vs the < 5%WLG (0.42 [0.22–0.82]).
- Insomnia and daytime sleepiness also improved more in participants exhibiting ≥ 5% weight loss.
- The dose-response relationship between weight loss and improvement in OSA severity was evident regardless of self-reported CPAP use.
Conclusions
The authors conclude that even a < 5% weight loss was sufficient for improvements in respiratory events and oximetry indices, but the prevalence of severe OSA reduced only after a ≥ 5% weight loss, and patients achieving a ≥ 10% weight loss exhibited the greatest benefits compared to weight-stable/gain patients.
Clinical practice applications:
These findings might be useful for Nutritional Therapists and Clinical Practitioners:
- Clinicians should aim for a ≥ 5% weight loss, and ideally a ≥ 10% weight loss, to achieve clinically meaningful reductions in OSA severity.
- Improvements after weight loss were significant even though a healthy body weight was not achieved.
Considerations for future research:
- The study sample consisted of predominantly male, overweight, otherwise healthy patients with moderate-to-severe OSA. Therefore, findings cannot be generalised to the whole OSA population and further research is required with broader, diverse, study samples.
- 6 months is a short duration period, therefore longer trials are required.
- Self-reported CPAP use by participants is a limitation of this study. Further robust analysis methods should be considered for future trials.
- Participants were advised to abstain from CPAP therapy for 2 days prior to the follow-up PSG but this was not evaluated or confirmed in this study and should be in future research.
Abstract
STUDY OBJECTIVES Lifestyle-induced weight loss is a complementary therapeutic approach for obstructive sleep apnea (OSA). We aimed at identifying the dose-response relationship between weight loss and OSA severity improvement. METHODS This is a secondary analysis of a 6-month clinical trial in 180 adult, overweight/obese moderate-to-severe OSA patients. Participants were randomized to a standard care, a Mediterranean diet, or a Mediterranean lifestyle arm. All patients were prescribed with continuous positive airway pressure (CPAP), while intervention arms additionally participated in a weight-loss dietary/lifestyle intervention. Based on percent change in weight at 6 months, participants were categorized into a weight-stable/gain (WS/GG) group or 3 weight-loss groups (WLG): < 5%WLG, 5%-10%WLG, and ≥ 10%WLG. Polysomnographic data and OSA symptoms were evaluated preintervention and postintervention. RESULTS Respiratory events and oximetry indices improved only in patients who lost weight and improvements were proportional to the degree of weight loss. Median percent change in apnea-hypopnea index (AHI) was -11.7%, - 37.9%, and - 49.3% in the < 5%WLG, 5%-10%WLG, and ≥ 10%WLG, respectively (P < .001). Compared to the WS/GG, the age-, sex-, baseline-, and CPAP use-adjusted relative risk (95% confidence interval) of severe OSA (AHI ≥ 30 events/h) was 0.45 (0.23-0.87) in the 5%-10%WLG and 0.32 (0.17-0.64) in the ≥ 10%WLG; the risk was also lower in the ≥ 10%WLG vs the < 5%WLG (0.42 [0.22-0.82]). Insomnia and daytime sleepiness also improved more in participants exhibiting ≥ 5% weight loss. CONCLUSIONS Even a < 5% weight loss can reduce respiratory events, but a ≥ 5% and ideally ≥ 10% weight loss is necessary for reducing the prevalence of severe OSA. CLINICAL TRIAL REGISTRATION Registry: ClinicalTrials.gov; Name: Mediterranean Diet/Lifestyle Intervention in Obstructive Sleep Apnea; URL: https://clinicaltrials.gov/ct2/show/NCT02515357; Identifier: NCT02515357. CITATION Georgoulis M, Yiannakouris N, Kechribari I, et al. Dose-response relationship between weight loss and improvements in obstructive sleep apnea severity after a diet/lifestyle intervention: secondary analyses of the "MIMOSA" randomized clinical trial. J Clin Sleep Med. 2022;18(5):1251-1261.
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Long Term Weight Loss Diets and Obesity Indices: Results of a Network Meta-Analysis.
Jabbour, J, Rihawi, Y, Khamis, AM, Ghamlouche, L, Tabban, B, Safadi, G, Hammad, N, Hadla, R, Zeidan, M, Andari, D, et al
Frontiers in nutrition. 2022;9:821096
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Plain language summary
Obesity is associated with a decreased lifetime expectancy of 5–20 years, depending on the severity and the presence of comorbidities. Diet therapy remains one of the cornerstones of the multi-disciplinary approach to weight management. The aim of this study was to evaluate the association of long-term dietary interventions, categorised using the Acceptable Macronutrient Distribution Ranges, with changes in weight parameters. This study is a systematic review and network meta-analysis of fifty studies. Results indicate that compared with the usual diet, all dietary interventions allow a sustained modest weight loss during the follow-up of 12 months and beyond. Diets did not differ among each other, with the exception of the high-fat low-carbohydrate diet that was slightly better than the low-carbohydrate, low-fat, and moderate macronutrients diet, with a larger weight loss (of 0.8 kg) and body mass index loss (0.4 kg/m2 ). Authors conclude that even though their findings apply to the general population of patients with overweight/obesity, the long-term impact of dietary approaches on patients with chronic diseases should be further investigated.
Abstract
Background: Scientists have been investigating efficient interventions to prevent and manage obesity. This network meta-analysis (NMA) compared the effect of different diets [moderate macronutrients (MMs), low fat/high carbohydrate (LFHC), high fat/low carbohydrate (HFLC), and usual diet (UD)] on weight, body mass index (BMI), and waist circumference (WC) changes at ≥12 months. Methods: We searched Medline, Embase, PubMed databases, and the Cochrane Library. We systematically assessed randomized controlled trials (RCTs) evaluating dietary interventions on adults (mean BMI ≥ 25 kg/m2) receiving active dietary counseling for ≥12 months. We pooled the data using a random-effect NMA. We assessed the quality of the included RCTs using the Cochrane risk of bias (ROB) tool. Results: We included 36 trials, 14 of which compared HFLC with MM diets. Compared with UD, all diets were associated with a significant weight loss (WL) at ≥12 months, HFLC [mean difference in kg (95% CI): -5.5 (-7.6; -3.4)], LFHC [-5.0 (-7.1; -2.9)] and MM [-4.7 (-6.8; -2.7)]. HFLC, compared with MM diet, was associated with a slightly higher WL (of -0.77 kg) and drop in BMI (of -0.36 kg/m2), while no significant difference was detected in other dietary comparisons. WC was lower with all diets compared to UD, with no significant difference across specific diets. There was no significant interaction of the results with the pre-specified sub-groups. The ROB was moderate to high, mostly related to unclear allocation concealment, high dropout rate and unclear or lack of blinding of participants, providers, and outcome assessors. Conclusion: Dietary interventions extending over ≥12 months are superior to UD in inducing weight, BMI and WC loss. HFLC might be associated with a slightly higher WL compared with MM diets. Systematic Trial Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=103116, PROSPERO (CRD42018103116).