Effects of daily administration of melatonin before bedtime on fasting insulin, glucose and insulin sensitivity in healthy adults and patients with metabolic diseases. A systematic review and meta‐analysis

Introduction: Moderate alcohol consumption is associated with a reduced risk of type 2 diabetes, but this relation appears stronger for women than men. The reduced risk of diabetes could be explained by improved insulin sensitivity or glycemic status, but results of intervention studies on this relation are inconsistent. Our aim was to conduct a systematic review and meta-analysis of intervention studies investigating the effect of alcohol consumption on insulin sensitivity and glycemic status. Design: Systematic review and meta-analysis of intervention studies. Data sources: PubMed and Embase were searched until May 2013 using a pre-specified search string. Methods: Intervention studies on the effect of more than 2 weeks alcohol consumption on biological markers of insulin sensitivity or glycemic status were identified and assessed on their quality. Pooled standardized mean differences (SMD) were calculated using either fixed or random effects models. Gender-stratified analyses and sensitivity analyses excluding studies with high doses of alcohol (> 40 g/day). In a meta-regression the influence of dosage and duration of intervention was tested. Results: We included 14 intervention studies in a meta-analysis on 6 glycemic endpoints. Alcohol consumption did not influence insulin sensitivity (SMD=0.06 [-0.13 to 0.26]) or fasting glucose (SMD=0.09 [-0.09 to 0.27]). Alcohol consumption reduced HbA1c (SMD=-0.62 [-1.01 to -0.23], P=0.002) and insulin concentrations (SMD=-0.17 [-0.34 to 0.00] P=0.049) compared with the control group. In women, alcohol consumption reduced fasting insulin (SMD=-0.23 [-0.41 to -0.04], P=0.019) and improved insulin sensitivity (SMD=0.19 [-0.03 to 0.41], P=0.087), but no significant differences were observed among men. Results were similar when only studies with moderate alcohol dosages were analysed and were not influenced by dosage and duration of the intervention. Conclusions: This study showed that moderate alcohol consumption may reduce fasting insulin and improve insulin sensitivity among women, but not among men. These effects may provide an explanation for the relation between alcohol consumption and type 2 diabetes. Furthermore, moderate alcohol consumption may reduce HbA1c levels among both men and women.

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The Effect of Alcohol Consumption on Insulin Sensitivity and Glycemic Status: A Systematic Review and Meta-analysis of Intervention Studies

Diabetes Care ◽

10.2337/dc14-1556 ◽

2015 ◽

Vol 38 (4) ◽

pp. 723-732

Author(s):

Ilse C. Schrieks ◽

Annelijn L.J. Heil ◽

Henk F.J. Hendriks ◽

Kenneth J. Mukamal ◽

Joline W.J. Beulens

Keyword(s):

Systematic Review ◽

Insulin Sensitivity ◽

Alcohol Consumption ◽

Intervention Studies ◽

Meta Analysis ◽

Moderate Alcohol Consumption ◽

Fasting Insulin ◽

Improve Insulin Sensitivity ◽

Glycemic Status ◽

Reduced Risk

OBJECTIVE Moderate alcohol consumption is associated with a reduced risk of type 2 diabetes. This reduced risk might be explained by improved insulin sensitivity or improved glycemic status, but results of intervention studies on this relation are inconsistent. The purpose of this study was to conduct a systematic review and meta-analysis of intervention studies investigating the effect of alcohol consumption on insulin sensitivity and glycemic status. RESEARCH DESIGN AND METHODS PubMed and Embase were searched up to August 2014. Intervention studies on the effect of alcohol consumption on biological markers of insulin sensitivity or glycemic status of at least 2 weeks' duration were included. Investigators extracted data on study characteristics, outcome measures, and methodological quality. RESULTS Fourteen intervention studies were included in a meta-analysis of six glycemic end points. Alcohol consumption did not influence estimated insulin sensitivity (standardized mean difference [SMD] 0.08 [−0.09 to 0.24]) or fasting glucose (SMD 0.07 [−0.11 to 0.24]) but reduced HbA1c (SMD −0.62 [−1.01 to −0.23]) and fasting insulin concentrations (SMD −0.19 [−0.35 to −0.02]) compared with the control condition. Alcohol consumption among women reduced fasting insulin (SMD −0.23 [−0.41 to −0.04]) and tended to improve insulin sensitivity (SMD 0.16 [−0.04 to 0.37]) but not among men. Results were similar after excluding studies with high alcohol dosages (>40 g/day) and were not influenced by dosage and duration of the intervention. CONCLUSIONS Although the studies had small sample sizes and were of short duration, the current evidence suggests that moderate alcohol consumption may decrease fasting insulin and HbA1c concentrations among nondiabetic subjects. Alcohol consumption might improve insulin sensitivity among women but did not do so overall.

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The Effects of Coenzyme Q10 Supplementation on Lipid Profiles Among Patients with Metabolic Diseases: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Current Pharmaceutical Design ◽

10.2174/1381612824666180406104516 ◽

2018 ◽

Vol 24 (23) ◽

pp. 2729-2742 ◽

Cited By ~ 6

Author(s):

Nasrin Sharifi ◽

Reza Tabrizi ◽

Mahmood Moosazadeh ◽

Naghmeh Mirhosseini ◽

Kamran B. Lankarani ◽

...

Keyword(s):

Systematic Review ◽

Lipid Profile ◽

Coenzyme Q10 ◽

Metabolic Disorders ◽

Metabolic Diseases ◽

Meta Analysis ◽

Lipid Profiles ◽

Controlled Trials ◽

Serum Triglycerides ◽

Coq10 Supplementation

Background and objective: Oxidative stress and inflammation are key parameters in developing metabolic disorders. Hence, antioxidant intake might be an appropriate approach. Several studies have evaluated the effect of coenzyme Q10 (CoQ10) supplementation on lipid profile among patients with metabolic diseases, though findings are controversial. The aim of this systematic review and meta-analysis was to determine the effects of CoQ10 supplementation on lipid profile in patients with metabolic disorders. Methods: We searched PubMed, EMBASE, Web of Science and Cochrane Library databases until July 2017. Prospective clinical trials were selected assessing the effect of CoQ10 supplementation on different biomarkers. Two reviewers independently assessed the eligibility of studies, extracted data, and evaluated the risk of bias of included studies. A fixed- or random-effects model was used to pool the data, which expressed as a standardized mean difference with 95% confidence interval. Heterogeneity was measured using a Q-test and with I2 statistics. Results: A total of twenty-one controlled trials (514 patients and 525 controls) were included. The meta-analysis indicated a significant reduction in serum triglycerides levels (SMD -0.28; 95% CI, -0.56, -0.005). CoQ10 supplementation also decreased total-cholesterol (SMD -0.07; 95% CI, -0.45, 0.31), increased LDL- (SMD 0.04; 95% CI, -0.27, 0.36), and HDL-cholesterol levels (SMD 0.10; 95% CI, -0.32, 0.51), not statistically significant. Conclusion: CoQ10 supplementation may significantly reduce serum triglycerides levels, and help to improve lipid profiles in patients with metabolic disorders. Additional prospective studies are recommended using higher supplementation doses and longer intervention period.

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