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Reproductive Health Feb 2024Polycystic ovary syndrome (PCOS) is a common condition in women, characterised by reproductive and metabolic dysfunction. While dietary approaches have been evaluated as... (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
Polycystic ovary syndrome (PCOS) is a common condition in women, characterised by reproductive and metabolic dysfunction. While dietary approaches have been evaluated as a first-line treatment for patients with PCOS, there is limited evidence to support preference for a specific dietary composition. This systematic review and network meta-analysis was performed with the objective of comparing different dietary interventions in terms of positive impact. Metformin, the currently preferred treatment, was also compared.
METHODS
The latest systematic search was performed on the 20th of March, 2023. Eligible randomised controlled trials (RCTs) included patients with PCOS and compared the dietary approach with another intervention or a standard diet. Outcomes were expressed via anthropometric measurements and hormonal, glycemic, and lipid levels. The Bayesian method was used to perform a network meta-analysis and to calculate the surface under the cumulative ranking curve (SUCRA) values in order to rank the dietary interventions. The overall quality of the evidence was assessed using the Grading of Recommendations Assessment, Development, and Evaluation system.
RESULTS
19 RCTs were identified, comprising data from 727 patients who were variously treated with 10 types of dietary interventions and metformin. The Dietary Approaches to Stop Hypertension (DASH) diet was the most effective in reducing Homeostatic Model Assessment of Insulin Resistance (SUCRA 92.33%), fasting blood glucose (SUCRA 85.92%), fasting insulin level (SUCRA 79.73%) and triglyceride level (SUCRA 82.07%). For body mass index (BMI), the most effective intervention was the low-calorie diet (SUCRA 84.59%). For weight loss, the low-calorie diet with metformin (SUCRA 74.38%) was the most effective intervention. Metformin produced the greatest reductions in low-density lipoprotein cholesterol (SUCRA 78.08%) and total testosterone levels (SUCRA 71.28%). The low-carb diet was the most effective intervention for reducing cholesterol levels (SUCRA 69.68%), while the normal diet (SUCRA 65.69%) ranked first for increasing high-density lipoprotein cholesterol levels.
CONCLUSION
Dietary interventions vary in their effects on metabolic parameters in women with PCOS. Based on our results, the DASH diet is the most effective dietary intervention for treating PCOS. Registration PROSPERO ID CRD42021282984.
Topics: Female; Humans; Polycystic Ovary Syndrome; Network Meta-Analysis; Metformin; Diet; Cholesterol
PubMed: 38388374
DOI: 10.1186/s12978-024-01758-5 -
Journal of Medical Internet Research Feb 2024Telehealth-based dietary interventions were recommended for cardiovascular disease (CVD) management during the COVID-19 pandemic; however, data regarding their... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Telehealth-based dietary interventions were recommended for cardiovascular disease (CVD) management during the COVID-19 pandemic; however, data regarding their effectiveness and feasibility are limited.
OBJECTIVE
We aimed to examine (1) the effectiveness of telehealth-based dietary interventions in improving clinical CVD risk factors and (2) the feasibility of these interventions among individuals with CVD.
METHODS
To conduct this systematic review and meta-analysis of randomized controlled trials (RCTs), 2 investigators searched PubMed, Cochrane Library, Web of Science, and ClinicalTrials.gov databases based on predetermined search terms and included English-language RCTs published between January 2000 and July 2022. The Cochrane Risk of Bias tool was used to assess RCT quality. To evaluate intervention effectiveness, weight, BMI, systolic and diastolic blood pressure, and levels of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, or blood glucose were compared postintervention in telehealth and usual care (UC) groups. Feasibility was determined through the number of participants retained in intervention and UC groups. Pooled data for each CVD outcome were analyzed using a random effects model. Mean difference (MD), standardized MD, or risk ratio were calculated using R software.
RESULTS
A total of 13 RCTs with 3013 participants were included in the analysis to assess the effectiveness and feasibility of telehealth-based dietary interventions among individuals with CVD. Participants had a mean age of 61.0 (SD 3.7) years, and 18.5% (n=559) were women. Approximately one-third of RCTs were conducted in the United States (n=4, 31%). Included studies used telephone, app, text, audio-visual media, or website-based interventions. Of the 13 included studies, 3 were of high quality, 9 were of moderate quality, and only 1 was of low quality. Pooled estimates showed systolic blood pressure (MD -2.74, 95% CI -4.93 to -0.56) and low-density lipoprotein cholesterol (standardized MD -0.11, 95% CI -0.19 to -0.03) to be significantly improved among individuals with CVD as a result of telehealth-based dietary interventions compared to UC. No significant difference in effectiveness was detected for weight, BMI, and levels of diastolic blood pressure, total cholesterol, high-density lipoprotein, and triglycerides between telehealth-based dietary interventions and UC among those with CVD. There was no significant difference between the feasibility of telehealth-based dietary interventions versus UC. Significant I indicated moderate to considerable heterogeneity.
CONCLUSIONS
Telehealth-based dietary interventions show promise in addressing CVD risk factors.
Topics: Female; Humans; Middle Aged; Male; Cardiovascular Diseases; Feasibility Studies; Triglycerides; Cholesterol, LDL; Cholesterol, HDL; Telemedicine
PubMed: 38363635
DOI: 10.2196/49178 -
The Cochrane Database of Systematic... Feb 2024The prevalence of gallstones varies between less than 1% and 64% in different populations and is thought to be increasing in response to changes in nutritional intake... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The prevalence of gallstones varies between less than 1% and 64% in different populations and is thought to be increasing in response to changes in nutritional intake and increasing obesity. Some people with gallstones have no symptoms but approximately 2% to 4% develop them each year, predominantly including severe abdominal pain. People who experience symptoms have a greater risk of developing complications. The main treatment for symptomatic gallstones is cholecystectomy. Traditionally, a low-fat diet has also been advised to manage gallstone symptoms, but there is uncertainty over the evidence to support this.
OBJECTIVES
To evaluate the benefits and harms of modified dietary fat intake in the treatment of gallstone disease in people of any age.
SEARCH METHODS
We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials in the Cochrane Library, MEDLINE ALL Ovid, Embase Ovid, and three other databases to 17 February 2023 to identify randomised clinical trials in people with gallstones. We also searched online trial registries and pharmaceutical company sources, for ongoing or unpublished trials to March 2023.
SELECTION CRITERIA
We included randomised clinical trials (irrespective of language, blinding, or status) in people with gallstones diagnosed using ultrasonography or conclusive imaging methods. We excluded participants diagnosed with another condition that may compromise dietary fat tolerance. We excluded trials where data from participants with gallstones were not reported separately from data from participants who did not have gallstones. We included trials that investigated other interventions (e.g. trials of drugs or other dietary (non-fat) components) providing that the trial groups had received the same proportion of drug or other dietary (non-fat) components in the intervention.
DATA COLLECTION AND ANALYSIS
We intended to undertake meta-analysis and present the findings according to Cochrane recommendations. However, as we identified only five trials, with data unsuitable and insufficient for analyses, we described the data narratively.
MAIN RESULTS
We included five trials but only one randomised clinical trial (69 adults), published in 1986, reported outcomes of interest to the review. The trial had four dietary intervention groups, three of which were relevant to this review. We assessed the trial at high risk of bias. The dietary fat modifications included a modified cholesterol intake and medium-chain triglyceride supplementation. The control treatment was a standard diet. The trial did not report on any of the primary outcomes in this review (i.e. all-cause mortality, serious adverse events, and health-related quality of life). The trial reported on gallstone dissolution, one of our secondary outcomes. We were unable to apply the GRADE approach to determine certainty of evidence because the included trial did not provide data that could be used to generate an estimate of the effect on this or any other outcome. The trial expressed its finding as "no significant effect of a low-cholesterol diet in the presence of ursodeoxycholic acid on gallstone dissolution." There were no serious adverse events reported. The included trial reported that they received no funding that could bias the trial results through conflicts of interest. We found no ongoing trials.
AUTHORS' CONCLUSIONS
The evidence about the effects of modifying dietary fat on gallstone disease versus standard diet is scant. We lack results from high-quality randomised clinical trials which investigate the effects of modification of dietary fat and other nutrient intakes with adequate follow-up. There is a need for well-designed trials that should include important clinical outcomes such as mortality, quality of life, impact on dissolution of gallstones, hospital admissions, surgical intervention, and adverse events.
Topics: Adult; Humans; Gallstones; Quality of Life; Cholesterol; Dietary Fats
PubMed: 38318932
DOI: 10.1002/14651858.CD012608.pub3 -
Systematic Reviews Feb 2024The present study aimed to investigate the effects of fish oil supplements compared to corn oil on serum lipid profiles by performing a meta-analysis of randomized... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The present study aimed to investigate the effects of fish oil supplements compared to corn oil on serum lipid profiles by performing a meta-analysis of randomized controlled trials (RCTs).
METHODS
Online databases including PubMed, Web of Science, and Scopus were searched until 30 December 2022. Pooled effect sizes were reported as the weighted mean difference (WMD) with 95% confidence intervals (CI). The Cochrane Collaboration's risk-of-bias tool was utilized to evaluate the quality of the studies. Lipid parameters, including triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL), and high-density lipoprotein cholesterol (HDL), were assessed in the meta-analysis.
RESULTS
Overall, 16 eligible trials were included in this systematic review and meta-analysis. The results revealed that the fish oil supplements significantly reduced TG (WMD: - 25.50 mg/dl, 95% CI: - 42.44, - 8.57, P = 0.000) levels compared to corn oil. Also, in this study, fish oil supplements had a positive and significant effect on HDL (WMD: 2.54 mg/dl, 95% CI: 0.55, 4.52). There were no significant changes in TC and LDL.
CONCLUSIONS
Our findings showed the effects of fish oil supplements on reducing TG and increasing HDL-c compared to corn oil. Further larger and well-designed RCTs are required to confirm these data.
Topics: Humans; Fish Oils; Corn Oil; Randomized Controlled Trials as Topic; Dietary Supplements; Triglycerides; Cholesterol, HDL
PubMed: 38317191
DOI: 10.1186/s13643-023-02426-8 -
Nutrition, Metabolism, and... Apr 2024The aim of this study was to conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) that evaluated the impact of sesame supplementation on... (Meta-Analysis)
Meta-Analysis
Effect of sesame supplementation on body composition and lipid profile in patients with type 2 diabetes: A systematic review and meta-analysis of randomized controlled trials.
AIMS
The aim of this study was to conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) that evaluated the impact of sesame supplementation on body weight (BW), body mass index (BMI), triglycerides (TGs), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C), and high-density lipoprotein-cholesterol (HDL-C) in patients with type 2 diabetes mellitus (T2DM).
DATA SYNTHESIS
PubMed, Scopus, ISI Web of Science, and Embase were searched without any restrictions until September 2023.Only RCTs reporting the effects of sesame supplementation on body composition and lipid profiles were included, while observational studies and animal models were excluded. The methodological quality of the studies was assessed using the Cochrane risk of bias tool. Out of 997 studies identified, 10 were included in the systematic review and meta-analysis. Our meta-analysis suggested a significant association between sesame supplementation and reduction in TG (weighted mean difference (WMD): -37.61 mg/dl, 95 % CI: -61.48, 13.73), TC (WMD: -32.69 mg/dl, 95 % CI: -47.26, 18.12), and LDL-C (WMD: -28.72 mg/dl, 95 % CI: -44.68, 12.76). However, our meta-analysis indicated that the supplementary intake of sesame had no significant effect on HDL-C, BW, and BMI in patients with T2DM.
CONCLUSIONS
This study showed that sesame consumption significantly lowered TG, TC, and LDL-C levels, which may have contributed to the improvement of clinical symptoms in T2DM. However, given the limited number of trials included in the analysis, additional large-scale studies are needed to confirm the effects of sesame consumption on the lipid profile and body composition in patients with T2DM.
PROSPERO CODE
CRD42023460630.
Topics: Animals; Humans; Lipids; Sesamum; Cholesterol, LDL; Randomized Controlled Trials as Topic; Diabetes Mellitus, Type 2; Cholesterol, HDL; Body Weight; Body Composition; Dietary Supplements
PubMed: 38316576
DOI: 10.1016/j.numecd.2024.01.020 -
Nutrition, Metabolism, and... Mar 2024Chronic metabolic acidosis has been shown to be associated with cardiometabolic risk factors. The aim of the currently updated meta-analysis was to explore the... (Meta-Analysis)
Meta-Analysis
AIMS
Chronic metabolic acidosis has been shown to be associated with cardiometabolic risk factors. The aim of the currently updated meta-analysis was to explore the association between Potential Renal Acid Load (PRAL) and Net Endogenous Acid Production (NEAP) with these risk factors.
DATA SYNTHESIS
Databases were searched up to May 2023. The mean of waist circumference (WC), body mass index (BMI), high- and low-density lipoprotein-cholesterol (HDL-C and LDL-C), triglyceride (TG), total cholesterol (TC), fasting blood sugar (FBS), and systolic- and diastolic blood pressure (SBP and DBP) in highest category vs lowest categories of NEAP and PRAL were recorded. Effect sizes were generated as weighted mean difference (WMD). Results showed that SBP, DBP, and WC had a significant difference in the upper and lower categories of PRAL (WMD: 1.466 mmHg; 95% CI: 2.121, -0.811; P<0.001, WMD: 0.710 mmHg; 95 % CI: 1.170, -0.249; P=0.003, and WMD: 0.819 cm; 95% CI: 1.446, -0.192; P=0.010) or NEAP (WMD: 1.690 mmHg; 95% CI: 2.789, -0.591; P=0.003, WMD: 1.076 mmHg, and WMD: 1.325 cm; 95% CI: 1.901, -0.749; P<0.001; 95% CI: 1.938, -0.214; P =0.014). The lowest versus highest categories of dietary PRAL were associated with lower BMI (WMD: 0.297 kg/m2; 95 % CI: 0.440, -0.154; P<0.001) and TG (WMD: 2.280 mg/dl; 95%CI: 3.828, -0.732; P=0.004; I=99.4 %; P<0.001).
CONCLUSIONS
High DAL can be considered as an independent risk factor for increasing anthropometric indices, blood pressure, and TG. This study registered in the PROSPERO database (Registration No. CRD42023402985).
Topics: Humans; Diet; Risk Factors; Anthropometry; Cholesterol, HDL; Cardiovascular Diseases
PubMed: 38316575
DOI: 10.1016/j.numecd.2024.01.013 -
Journal of Research in Health Sciences Dec 2023According to the findings from observational studies and clinical trials assessing the effect of vitamin D supplements on cardiovascular diseases (CVDs), there are still... (Meta-Analysis)
Meta-Analysis Review
Vitamin D Supplementation and Cardiovascular Disease Risks in More Than 134000 Individuals in 29 Randomized Clinical Trials and 157000 Individuals in 30 Prospective Cohort Studies: An Updated Systematic Review and Meta-analysis.
BACKGROUND
According to the findings from observational studies and clinical trials assessing the effect of vitamin D supplements on cardiovascular diseases (CVDs), there are still contradictory results. This systematic review aimed to assess the effect of vitamin D supplements on CVDs considering cohort studies and clinical trials. A systematic review.
METHODS
MEDLINE/PubMed, Science Direct, Embase, and Cochrane Library databases were reviewed by two reviewers independently until 2022. The study effect is risk ratio (RR) and 95% confidence interval (CI) according to Mantel Haenszel's random-effects model. Then, Stata version 14 was used for statistical analysis.
RESULTS
In clinical trial studies, the incidence of CVDs among the vitamin D-consuming group was not significantly different from that in the placebo group (RR: 0.99, 95% CI: 0.95-1.03; =0.77; I =0%). CVD mortality was also not significantly different between the two groups (RR: 0.97, 95% CI: 0.90-1.05; =0.72; I=0%). In cohort studies, circulating 25 (OH) D increased the risk of CVD incidence by 31% (RR: 1.31, 95% CI: 1.19-1.45) and CVD mortality by 37% (RR: 1.37, 95% CI: 1.17-1.61).
CONCLUSION
According to current evidence from clinical trials, vitamin D supplementation should not be recommended for CVD prevention. However, there is a direct association between vitamin D deficiency and the incidence of CVDs as well as its mortality. According to the results of clinical trial studies carrying higher levels of scientific evidence, it can be concluded that vitamin D supplementation does not exert a significant effect on the incidence, mortality, and reduction of CVDs.
Topics: Humans; Cardiovascular Diseases; Prospective Studies; Randomized Controlled Trials as Topic; Vitamins; Vitamin D; Dietary Supplements
PubMed: 38315909
DOI: 10.34172/jrhs.2023.129 -
Semergen 2024Monacolin K is the major active component in red yeast rice (RYR) which is structurally identical to lovastatin and has the most powerful effect, in terms of reducing... (Review)
Review
Monacolin K is the major active component in red yeast rice (RYR) which is structurally identical to lovastatin and has the most powerful effect, in terms of reducing blood cholesterol levels. This review aimed to examine the effect and safety of different doses of monacolin K on blood cholesterol levels. PubMed and Cochrane were searched for articles published between 2012 and 2023 for clinical-trials and randomized-controlled-trials. Eligible studies included participants>18-years-old, of any gender and ethnicity. The intervention/exposure of interest was monacolin K. Hypercholesterolemia was considered the outcome of interest defined as the elevated total or low-density-lipoprotein (LDL) cholesterol levels. 12 randomized-controlled-trials were eligible for inclusion in the analysis including 769 participants>18-years-old. 11 out of 12 studies were assessed with high methodological quality and one study with low methodological quality. Monacolin K supplementation varied between 2mg and 10mg per day and the maximum period of supplementation was 12 weeks. All studies indicated a beneficial effect of monacolin supplementation on LDL and total cholesterol levels (p<0.05) regardless the dose and period of supplementation. Also, 3 of the included studies reported adverse side effects after treatment with monacolin K. Low doses of monacolin K equal to 3mg/day exert potential cholesterol-lowering effects although the number of relative studies is limited. Regarding the safety of monacolin K supplementation, findings seem to be more controversial and therefore, it is suggested for all patients treated with monacolin K to be routinely monitored regardless the dose of supplementation.
Topics: Humans; Hypercholesterolemia; Dietary Supplements; Randomized Controlled Trials as Topic; Lovastatin; Anticholesteremic Agents; Cholesterol, LDL; Dose-Response Relationship, Drug; Cholesterol; Biological Products; Dicarboxylic Acids; Fatty Acids
PubMed: 38310834
DOI: 10.1016/j.semerg.2023.102156 -
European Journal of Clinical... Jun 2024Stroke represents a significant public health challenge, necessitating the exploration of preventive measures. This network meta-analysis aimed to assess the efficacy of... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND AND AIM
Stroke represents a significant public health challenge, necessitating the exploration of preventive measures. This network meta-analysis aimed to assess the efficacy of different vitamin treatments compared to a placebo in preventing stroke.
METHODS
A systematic electronic search in databases including PubMed, EmBASE, Web of Science, clinicaltrials.gov, and Google Scholar until 31 May 2023 was conducted, to identify published studies investigating the association between vitamin intake and the risk of stroke. Pooled risk ratio (RR) with 95% confidence intervals (CIs) was calculated using a frequentist network meta-analysis. Furthermore, we ranked vitamins based on p-scores, facilitating a comparative assessment of their effectiveness in preventing stroke.
RESULTS
A total of 56 studies, including 17 randomized controlled trials (RCTs) and 39 cohort studies were analyzed. Direct estimates obtained from network meta-analysis, we found that vitamin A (RR: .81 [.72-.91]), vitamin B-complex (RR: .85 [.74-.97]), vitamin B (RR: 79 [.68-.92]), folate (RR: .86 [.75-.97]), vitamin C (RR: .77 [.70-.85]) and vitamin D (RR: .73 [.64-.83]) were significantly associated with a decreased stroke risk. However, no significant association was observed for vitamin B, vitamin B, and vitamin E. Subsequent to network meta-analysis, vitamins were ranked in decreasing order of their efficacy in stroke prevention based on p-score, with vitamin D (p-score = .91), vitamin C (p-score = .79), vitamin B (p-score = .70), vitamin A (p-score = .65), vitamin B-complex (p-score = .53), folate (p-score = .49), vitamin B (p-score = .39), vitamin E (p-score = .28), vitamin B (.13) and placebo (.10).
CONCLUSION
Our study has established noteworthy connections between vitamin A, vitamin B-complex, vitamin B, folate, vitamin C, and vitamin D in the realm of stroke prevention. These findings add substantial weight to the accumulating evidence supporting the potential advantages of vitamin interventions in mitigating the risk of stroke. However, to solidify and validate these observations, additional research is imperative. Well-designed clinical trials or cohort studies are needed to further explore these associations and formulate clear guidelines for incorporating vitamin supplementation into effective stroke prevention strategies.
Topics: Humans; Vitamins; Stroke; Vitamin B Complex; Folic Acid; Network Meta-Analysis; Vitamin D; Vitamin E; Ascorbic Acid; Vitamin A; Vitamin B 6; Randomized Controlled Trials as Topic; Dietary Supplements
PubMed: 38291560
DOI: 10.1111/eci.14165 -
European Journal of Nutrition Apr 2024The objective of this systematic review was to determine a minimum serum 25-hydroxyvitamin D (25OHD) threshold based on the risk of having rickets in young children.... (Meta-Analysis)
Meta-Analysis Review
Serum 25-hydroxyvitamin D threshold and risk of rickets in young children: a systematic review and individual participant data meta-analysis to inform the development of dietary requirements for vitamin D.
PURPOSE
The objective of this systematic review was to determine a minimum serum 25-hydroxyvitamin D (25OHD) threshold based on the risk of having rickets in young children. This work was commissioned by the WHO and FAO within the framework of the update of the vitamin D requirements for children 0-3 years old.
METHODS
A systematic search of Embase was conducted to identify studies involving children below 4 years of age with serum 25OHD levels and radiologically confirmed rickets, without any restriction related to the geographical location or language. Study-level and individual participant data (IPD)-level random effects multi-level meta-analyses were conducted. The odds, sensitivity and specificity for rickets at different serum 25OHD thresholds were calculated for all children as well as for children with adequate calcium intakes only.
RESULTS
A total of 120 studies with 5412 participants were included. At the study-level, children with rickets had a mean serum 25OHD of 23 nmol/L (95% CI 19-27). At the IPD level, children with rickets had a median and mean serum 25OHD of 23 and 29 nmol/L, respectively. More than half (55%) of the children with rickets had serum 25OHD below 25 nmol/L, 62% below 30 nmol/L, and 79% below 40 nmol/L. Analysis of odds, sensitivities and specificities for nutritional rickets at different serum 25OHD thresholds suggested a minimal risk threshold of around 28 nmol/L for children with adequate calcium intakes and 40 nmol/L for children with low calcium intakes.
CONCLUSION
This systematic review and IPD meta-analysis suggests that from a public health perspective and to inform the development of dietary requirements for vitamin D, a minimum serum 25OHD threshold of around 28 nmol/L and above would represent a low risk of nutritional rickets for the majority of children with an adequate calcium intake.
Topics: Child; Humans; Child, Preschool; Infant, Newborn; Infant; Calcium; Vitamin D Deficiency; Vitamin D; Rickets; Vitamins; Calcifediol; Nutritional Requirements
PubMed: 38280944
DOI: 10.1007/s00394-023-03299-2