Using the Methodology of Systematic Review of Reviews for Evidence-Based Medicine

Systematic Review of Reviews without abstract. Authors' invited you to read the whole review article since it is short

Coagulopathy: Another side effect of coronavirus infection

Recently, coronavirus disease 2019 (COVID-19) has been considered as a major health problem around the globe. This severe acute respiratory syndrome has a bunch of features, such as high transmission rate, which are adding to its importance. Overcoming this disease relies on a complete understanding of the viral structure, receptors, at-risk cells or tissues, and pathogenesis. Currently, researches have shown that besides the lack of a proper anti-viral therapeutic method, complications provided by this virus are also standing in the way of decreasing its mortality rate. One of these complications is believed to be a hematologic manifestation. Commonly, three kinds of coagulopathies are detected in COVID-19 patients: disseminated intravascular coagulation (DIC), pulmonary embolism (PE), and deep vein thrombosis (DVT). In this paper, we have reviewed the relation between these conditions and coronavirus-related diseases pathogenesis, severity, and mortality rate

Effects of propolis supplementation on glycemic status, lipid profiles, inflammation and oxidative stress, liver enzymes, and body weight: a systematic review and meta-analysis of randomized controlled clinical trials

The aim of meta-analysis was to assess the effects of propolis on markers of oxidative stress, lipid profiles, inflammation and glycemic control, liver enzymes, and weight control. The heterogeneity between the included studies was indicated using the Cochrane’s Q test and I-square (I2 ) statistic. 14 trials were included in this meta-analysis. Our meta-analysis indicated a significant reduction in fating glucose (WMD: -17.00; 95% CI: −30.88, −3.11), HbA1C (WMD: -0.42; 95% CI: −0.75, −0.10), and insulin (WMD: -1.75; 95% CI: −3.24, −0.26) and a marginally significant reduction in insulin resistance (WMD: -0.60; 95% CI: −1.20, 0.00) following propolis supplementation in 10, 8, 6, and 5 studies, respectively. Pooling 5 effect sizes, a significant reduction was seen in ALT (WMD: -5.63; 95% CI: −10.59, −0.67) and aspartate aminotransferase (AST) (WMD: -3.09; 95% CI: −5.15, −1.03) following propolis. A significant beneficial effect was observed for CRP (WMD: -1.11; 95% CI: −1.92, −0.29), TNF-α (WMD: -6.71; 95% CI: −9.44, −3.98) and interleukin-6 (IL-6) (WMD: -17.99; 95% CI: −35.56, −0.42) concentrations after propolis supplementation. This study demonstrated the beneficial effects of propolis on FPG, HbA1c, insulin, CRP, TNF-α and liver enzymes levels

Fetuin-A and vitamin D receptor gene polymorphisms in hemodialysis patients

Introduction: Vascular calcification is a common complication in the chronic kidney disease (CKD) patients and the leading cause of morbidity and mortality in this patient. The aim of the present study was to evaluate a possible correlation between vitamin D receptor (VDR) gene FokI and ApaI polymorphisms with the expression of calcification biomarkers such as Fetuin-A and intact parathyroid hormone (iPTH) in hemodialysis (HD) patients. Methods: In this cross-sectional study, serums were obtained from 46 stable chronic HD patients. The serum levels of iPTH, Fetuin-A, vitamin D, calcium, phosphorus, and VDR genotyping were determined by standard methods. Results: Serum levels of Fetuin-A, calcium, and phosphorus did not differ between males and females, but significant differences in iPTH and vitamin D levels was found in the study patients [(336.8 ± 139.0 pg/dl) vs. (414.7 ± 111.8 pg/dl), P = 0.040 and (24.5 ± 7.6 ng/ml) vs. (19.9 ± 4.8 ng/ml), P = 0.020 respectively]. A significant correlations were found between serum phosphorus and levels of serum calcium (r = –0.4; P = 0.002), vitamin D (r = –0.5; P = 0.001) and iPTH (r = 0.4; P = 0.001). iPTH level in FokI polymorphism, were different between genotype groups in study patient (P = 0.020). There was a significant positive correlation between vitamin D and iPTH levels in patients with aa genotype (P = 0.020, r = 0.4). Conclusion: These findings suggest that FokI (rs2228570) polymorphism in exon-2 of the VDR gene may play a role in iPTH levels. Fetuin-A deficiency or high level of iPTH and its association with VDR gene polymorphisms may be useful to identify the high-risk group susceptible to renal failure and atherosclerosis. Although VDR gene FokI and ApaI polymorphisms could affect the levels of Fetuin-A and vitamin D, their direct role on atherosclerosis needs further studies in the future

The effects of L-carnitine supplementation on indicators of inflammation and oxidative stress: a systematic review and meta-analysis of randomized controlled trials

Objective: Several trials investigated the efficacy of L-carnitine administration on markers of inflammation and indicators of oxidative stress; however, their findings are controversial. The aim of this study was to conduct a comprehensive meta-analysis and a critical review, which would analyze all randomized controlled trials (RCTs) in order to determine the effects of L-carnitine supplementation on inflammatory markers and oxidative stress. ----- Methods: An electronic search was performed using Scopus, Cochrane Library, PubMed, Google scholar and Web of Science databases on publications from 1990 up to May 2020. Human RCTs conducted in healthy subjects or participants with certain disorders which investigating the efficacy of L-carnitine supplementation compared to control (placebo, usual treatment or no intervention) on inflammation and oxidative markers were included. Data were pooled applying a random-effects model and as the overall effect size, weighted mean difference (WMD) was presented. Between heterogeneity among studies was computed using Cochran's Q test and I-square (I2). Quality of studies assessed using the Jadad scale. Dose-response analysis was measured using meta-regression. The funnel plot, as well as the Egger's regression test was applied to determine the publication bias. ----- Results: 44 trials (reported 49 effect sizes for different outcomes of interest) met the inclusion criteria for this meta-analysis. According to the findings, L-carnitine supplementation resulted in a significant reduction in C-reactive protein (CRP) (WMD: -0.10; 95% CI: -0.14, -0.06), interleukin 6 (IL-6) (WMD: -1.87; 95% CI: -2.80, -0.95), tumor necrosis factor-α (TNF-α) levels (WMD: -1.43; 95% CI: -2.03, -0.84), and malondialdehyde (MDA) (WMD: -0.47; 95% CI: -0.76, -0.18) levels, while there was a significant increase in superoxide dismutase (SOD) (WMD: 2.14; 95% CI: 1.02, 3.25). However, no significant effects of L-carnitine on glutathione peroxidase (GPx) (WMD: 0.02; 95% CI: -0.01, 0.05) and total antioxidant capacity (TAC) (WMD: 0.14; 95% CI: -0.05, 0.33) were found. ----- Conclusions: L-carnitine supplementation was associated with lowering of CRP, IL-6, TNF-α, and MDA, and increasing SOD levels, but did not affect other inflammatory and oxidative stress biomarkers

The effects of vitamin D supplementation on muscle function among postmenopausal women

The loss of muscle mass and its strength is one of the most critical changes in aging which is associated with an increased risk of falls, osteoporotic fractures and mobility disability. Vitamin D, with its extra-skeletal benefits, might improve muscle function in elderly. The current systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to summarize available relevant data and determine the effect of vitamin D supplementation on muscle function among postmenopausal women. We reach ed databases including; Cochrane library, Embase, PubMed, and Web of Science database until the end of May 2018 to identify relevant published RCTs. Heterogeneity among included studies was assessed using Q-test and I2 statistics. Random-effect model was applied to pool data and weighted mean differen ce (WMD) was calculated representing summary effect size. Outcomes of interest included the eff ects of vitamin D supplementation on hand grip strength (HGS), back muscle strength (BMS), and Timed Up and Go (TUG). Twelve RCTs out of 1739 potential reports were included in our meta-analysis. The pooled findings showed that vitamin D supplementation had no significant effect on HGS (WMD -0.03 kilogram (Kg); 95 % CI, -0.26, 0.20; P=0.78), BMS (WMD 7.21 newton (N); 95 % CI, -5.98, 20.40; P=0.28), and TUG (WMD 0.01 second (S); 95 % CI, -0.17, 0.18; P=0.93) in postmenopausal women. Overall, the current meta-analysis showed that taking vitamin D supplementation by postmenopausal women did not affect markers of muscle function. Further studies are required to confirm the effect of vitamin D supplementation on markers of muscle function

The effects of omega-3 fatty acids supplementation on metabolic status in pregnant women: a systematic review and meta-analysis of randomized controlled trials

Background and objective: Data regarding the effects of omega-3 polyunsaturated fatty acids (PUFA) supplementation on metabolic status of pregnant women are limited. This systematic review and meta-analysis were done based on randomized controlled trials (RCTs) dealing with the effects of omega-3 PUFA supplementation on glycemic control, lipoproteins, inflammation and oxidative stress in pregnant women. ------ Methods: Following databases were searched for eligible studies published from inception to until 2019: MEDLINE, EMBASE, Web of Science, PubMed, Scopus, Cochrane Library, and Google scholar. Studies that evaluated the effect of omega-3 PUFA supplementation on parameters of glycemic control, lipoproteins, inflammation and oxidative stress in pregnant women were found by using the key MeSH. A study quality assessment was performed using the Cochrane Collaboration risk of bias tool and heterogeneity between studies was statistically computed using Cochrane's Q test and I-square (I2). Data were pooled using a random-effects model and weighted mean difference (WMD) was considered as the overall effect size. ------ Results: No significant effects of omega-3 PUFA supplementation on FPG, insulin, insulin resistance, total cholesterol, triglycerides, LDL-cholesterol, total cholesterol/HDL-cholesterol, interleukin 6 (IL-6), IL-8, and malondialdehyde were found. However, omega-3 PUFA significantly increased serum concentrations of HDL-cholesterol (WMD: 3.10; 95% CI: 0.18, 6.03) and reduced C-reactive protein (WMD: -1.85; 95% CI: -2.61, -1.09). ------ Conclusion: Based on the results of this meta-analysis omega-3 PUFA supplementation during pregnancy has a significant beneficial effect on HDL-cholesterol, and C-reactive protein

Effects of Nigella sativa on glycemic control, lipid profiles, and biomarkers of inflammatory and oxidative stress: A systematic review and meta-analysis of randomized controlled clinical trials

The aim of this systematic review and meta-analysis was to evaluate the effects of Nigella sativa (N. sativa) on glycemic control, lipid profiles, and biomarkers of inflammatory and oxidative stress. Two independent authors systematically examined online databases consisting of, EMBASE, Scopus, PubMed, Cochrane Library, and Web of Science from inception until October 30, 2019. Cochrane Collaboration risk of bias tool was applied to assess the methodological quality of the studied trials. The heterogeneity among the included studies were assessed using the Cochrane's Q test and I-square (I 2 ) statistic. Data were pooled using a random-effects model and weighted mean difference (WMD) was considered as the overall effect size. A total of 50 trials were included in this meta-analysis. We found a significant reduction in total cholesterol (WMD: −16.80; 95% CI: −21.04, −12.55), triglycerides (WMD: −15.73; 95% CI: −20.77, −10.69), LDL-cholesterol (WMD: −18.45; 95% CI: −22.44, −14.94) and VLDL-cholesterol (WMD: −3.72; 95% CI: −7.27, −0.18) following supplementation with N. sativa. In addition, there was significant reductive effect observed with N. sativa on fasting glucose (WMD: −15.18; 95% CI: −19.82, −10.55) and HbA1C levels (WMD: −0.45; 95% CI: −0.66, −0.23). Effects of N. sativa on CRP (WMD: −3.61; 95% CI: −9.23, 2.01), TNF-α (WMD: −1.18; 95% CI: −3.23, 0.86), TAC (WMD: 0.31; 95% CI: 0.00, 0.63), and MDA levels (WMD: −0.95; 95% CI: −2.18, 0.27) were insignificant. This meta-analysis demonstrated the beneficial effects of N. sativa on fasting glucose, HbA1c, triglycerides, total-, VLDL-, LDLcholesterol levels

Metabolic syndrome and its components among women with polycystic ovary syndrome: a systematic review and meta-analysis

Introduction: The objectives of this study were to provide an estimate of the prevalence of metabolic syndrome (MetS) and its components among women with PCOS; and calculate the odds ratio (OR) for MetS (using different definitions of MetS) in women with PCOS, compared to healthy controls

A systematic review and meta-analysis: The effects of probiotic supplementation on metabolic profile in patients with neurological disorders

Background and objective: The objective of meta-analysis of randomized controlled trials (RCTs) was to evaluate the effects of probiotic supplementation on metabolic status in patients with neurological disorders. Methods: The following databases were search up to April 2019: Pubmed, Scopus, Google scholar, Web of Science, and Cochrane Central Register of Controlled Trials. The quality of the relevant extracted data was assessed according to the Cochrane risk of bias tool. Data were pooled by the use of the inverse variance method and expressed as mean difference with 95 % Confidence Intervals (95 % CI). Results: Nine studies were included in this meta-analysis. The findings suggested that probiotic supplementation resulted in a significant reduction in C-reactive protein (CRP) [Weighted Mean Difference (WMD): -1.06; 95 % CI: -1.80, -0.32] and malondialdehyde (MDA) levels (WMD: -0.32; 95 % CI: -0.46, -0.18). Supplementation with probiotics also significantly reduced insulin (WMD: -3.02; 95 % CI: -3.88, -2.15) and homeostatic model assessment for insulin resistance (HOMA-IR) (WMD: -0.71; 95 % CI: -0.89, -0.52). Probiotics significantly reduced triglycerides (WMD: -18.38; 95 % CI: -25.50, -11.26) and VLDL-cholesterol (WMD: -3.16; 95 % CI: -4.53, -1.79), while they increased HDL-cholesterol levels (WMD: 1.52; 95 % CI: 0.29, 2.75). Conclusion: This meta-analysis demonstrated that taking probiotic by patients with neurological disorders had beneficial effects on CRP, MDA, insulin, HOMA-IR, triglycerides, VLDL-cholesterol and HDL-cholesterol levels, but did not affect other metabolic parameters