The efficacy of curcumin in relieving osteoarthritis: A meta-analysis of meta-analyses.

Osteoarthritis (OA) is one of the most prevalent degenerative joint diseases. Several meta-analyses have shown that curcumin could improve the function of the knee and alleviate pain in OA, while some meta-analyses demonstrate controversial results. Hence, we assessed curcumin's effects on knee OA in an umbrella meta-analysis. PubMed, Scopus, Embase, and Web of Science databases were employed to find English-language meta-analyses of randomized controlled trials investigating the effect of curcumin supplementation on OA outcomes up to September 2023. The visual analog scale (VAS), Western Ontario and McMaster Universities Arthritis Index (WOMAC) pain, function, and stiffness scales were analyzed. Effect sizes and 95% confidence intervals were utilized to obtain the overall effect size. A random-effects model was applied to perform the meta-analysis. Heterogeneity was determined by I2 statistics and the Cochrane Q-test. The pooled effect of the 11 included meta-analyses showed that curcumin could significantly decrease the VAS score (weighted mean difference [WMD] and standardized mean difference [SMD]), WOMAC-total (SMD and WMD), WOMAC-Function (SMD and WMD), WOMAC-Pain (SMD), and WOMAC-Stiffness scores (SMD) (p ≤ 0.001, ≤0.001, ≤0.001, 0.007, ≤0.001, 0.002, ≤0.001, ≤0.001, respectively). The results strongly support curcuminoid supplementation in relieving pain, improving joint mobility and stiffness, and shortening medication usage of OA patients.

The role of vitamin D in outcomes of critical care in COVID-19 patients: evidence from an umbrella meta-analysis of interventional and observational studies.

OBJECTIVES: Several meta-analyses have suggested the beneficial effect of vitamin D on patients infected with severe acute respiratory syndrome coronavirus-2. This umbrella meta-analysis aims to evaluate influence of vitamin D supplementation on clinical outcomes and the mortality rate of COVID-19 patients. DESIGN: Present study was designed as an umbrella meta-analysis. The following international databases were systematically searched till March 2023: Web of Science, PubMed, Scopus, and Embase. SETTINGS: Random-effects model was employed to perform meta-analysis. Using AMSTAR critical evaluation tools, the methodological quality of the included meta-analyses was evaluated. PARTICIPANTS: Adult patients suffering from COVID-19 were studied. RESULTS: Overall, 13 meta-analyses summarising data from 4 randomised controlled trial and 9 observational studies were identified in this umbrella review. Our findings revealed that vitamin D supplementation and status significantly reduced mortality of COVID-19 [Interventional studies: (ES = 0·42; 95 % CI: 0·10, 0·75, P < 0·001; I2 = 20·4 %, P = 0·285) and observational studies (ES = 1·99; 95 % CI: 1·37, 2·62, P < 0·001; I2 = 00·0 %, P = 0·944). Also, vitamin D deficiency increased the risk of infection and disease severity among patients. CONCLUSION: Overall, vitamin D status is a critical factor influencing the mortality rate, disease severity, admission to intensive care unit and being detached from mechanical ventilation. It is vital to monitor the vitamin D status in all patients with critical conditions including COVID patients.

The effect of Mediterranean diet instructions on depression, anxiety, stress, and anthropometric indices: A randomized, double-blind, controlled clinical trial.

Evidence suggests that adopting a healthy diet, such as the Mediterranean Diet (MD), can positively affect mental health. To further explore this, a study was conducted to determine the impact of MD instruction over 12 weeks on depression, anxiety, stress, and anthropometric indices. The study is a randomized, double-blind, controlled clinical trial with sixty participants who reported stress, anxiety, and depression conducted in Tabriz, Iran (2022-2023). They were randomly assigned to either the intervention group (n = 30), which received MD instruction, or the control group (n = 30), which received standard healthy nutrition education. Both groups were asked to follow their respective nutrition education plans for 12 weeks. After 12 weeks, depression, anxiety, and stress levels were measured using the DASS-21 questionnaire, and anthropometric indices were assessed. Initially, the unadjusted DASS-21 scores for depression, anxiety, and stress did not show significant differences between the two groups. However, after adjusting for baseline variables (model 2), all scores decreased significantly (the P-value for all scores was < 0.001). There was no significant difference in weight and BMI between the intervention and control groups. However, after adjusting the results based on baseline values (Model 2) and adherence to the program (Model 3), weight and BMI were significantly reduced in the MD group (P-values for both cases and both models were < 0.001). Overall, despite some significant findings, the results were not noticeable from a clinical perspective. The study provides some indications that following the Mediterranean diet may lead to improvements in weight and mental well-being.

The Effect of Vitamin D Supplementation on Lipid Profiles: an Umbrella Review of Meta-Analyses.

According to published meta-analyses, vitamin D exerts different beneficial effects in preventing and controlling risk factors associated with noncommunicable chronic diseases; however, the results are still conflicting. The purpose of this umbrella meta-analysis was to investigate the effect of vitamin D supplementation on low-density lipoprotein cholesterol, high-density lipoprotein (HDL) cholesterol, total cholesterol (TC), and triglyceride (TG) as components of the lipid profile. PubMed, Scopus, Web of Science, and Cochrane Database of Systematic Reviews were systematically searched for meta-analyses of randomized controlled trials. The umbrella meta-analysis followed the PRISMA guidelines. The random-effects model was employed to estimate the overall effect size (ES). Overall, 25 meta-analyses were included. In the standardized mean difference analysis, vitamin D significantly decreased TG (ES: -0.15; 95% CI: -0.23, -0.08; P ≤ 0.001) and TC levels (ES: -0.17; 95% CI: -0.23, -0.11; P ≤ 0.001) and increased HDL levels (ES: 0.08; 95% CI: 0.01, 0.15; P = 0.025). In the weighted mean difference analysis, vitamin D significantly decreased only TG levels (ES: -4.63 mg/dL; 95% CI: -7.70, -1.57; P = 0.003). The present study supports that vitamin D supplementation could be considered a beneficial adjuvant therapy in managing lipid profile levels, especially in individuals with vitamin D deficiency. This systematic review was registered in PROSPERO as CRD42022306334.

The Impact of Vitamin D Supplementation on Improving Blood Pressure: Evidence Obtained From an Umbrella Meta-analysis.

PURPOSE: The results of meta-analyses regarding the effect of vitamin D on blood pressure are conflicting. The present umbrella meta-analysis was conducted to provide definite and conclusive results. METHODS: Systematically, Scopus, EMBASE, PubMed, and Web of Science databases and Google Scholar were searched for relevant literature published up to July 2022. All meta-analyses of clinical trials addressing the effect of vitamin D on blood pressure were included. Random effects analysis was performed to obtain the overall effect size based on the standardized mean differences (SMDs) and weighted mean differences (WMDs) separately. The quality of included meta-analyses was assessed by using the Measurement Tool for Assessing Multiple Systematic Reviews 2 questionnaire. FINDINGS: Overall, 21 meta-analyses were enrolled in the umbrella review. The results indicated that systolic blood pressure was significantly reduced after the intervention based on WMD effect size analysis (ESWMD = -0.69 mm Hg; 95% CI, -1.35 to -0.04 [P < 0.038]; I2 = 46.7%, P = 0.021); however, no considerable impact was observed based on analysis of SMD effect sizes (ESSMD = -0.05 mm Hg; 95% CI, -0.24 to 0.14; P = 0.615). Also, vitamin D supplementation indicated a significant improvement in diastolic blood pressure based on WMD effect sizes (ESWMD = -0.66 mm Hg; 95% CI, -1.05 to -0.27 [P < 0.001]; I2 = 56.4%, P = 0.004) but not SMD analysis (ESSMD = -0.04 mm Hg; 95% CI, -0.13 to 0.04 [P = 0.328]; I2 = 53.4%, P = 0.057). IMPLICATIONS: Based on obtained evidence, vitamin D could be considered an efficient adjuvant for improving blood pressure.

The association between skeletal muscle mass index (SMI) and survival after gastrectomy: A systematic review and meta-analysis of cohort studies.

OBJECTIVE: Low skeletal muscle mass index (SMI) is frequently identified in gastric cancer patients but its association with patient survival rate is not clear. This systematic review and meta-analysis aimed to clarify the association between SMI and overall survival in gastric cancer patients after gastrectomy. METHODS: PubMed, Scopus, and Web of Science were searched from database inception until July 2021. Studies were eligible if they included gastric cancer patients, measured the SMI level, reported SMI before gastrectomy, defined sarcopenia according to SMI, and had a cohort or case-control design. Primary outcome was cancer survival rate. The risk of bias of individual studies was assessed using the Newcastle - Ottawa Scale. RESULTS: Overall, 22 cohort studies including 7,203 participants were included. The quality of the included studies was moderate to high. A higher overall survival rate was associated with a higher SMI (RR = 1.62, 95% CI: 1.42-1.85). Subgroup analysis suggested a stronger association in overweight or obese patients (RR = 2.39, 95% CI: 1.13-5.09; I2 = 77%; heterogeneity P < 0.01). But no significant differences in the association based on the surgery type (curative surgery vs radical surgery) or the type of gastrectomy (total gastrectomy vs sub-total gastrectomy) were observed. CONCLUSIONS: It is suggested that SMI can be a prognostic indicator for overall survival in gastric cancer patients, especially in overweight and obese patients.

The effect of propolis supplementation in improving antioxidant status: A systematic review and meta-analysis of controlled clinical trials.

The present study aimed to assess the effect of propolis supplementation on oxidative status, a key contributor to the etiology of many chronic diseases. A systematic search of multiple databases, including Web of Science, SCOPUS, Embase, PubMed, and Google Scholar, was conducted from inception to October 2022 to identify articles examining the effect of propolis on glutathione (GSH), glutathione peroxidase (GPX), total antioxidant capacity (TAC), superoxide dismutase (SOD), and malondialdehyde (MDA) levels. The quality of the included studies was evaluated using the Cochrane Collaboration tool. A total of nine studies were included in the final analysis, and a random-effects model was used to pool the estimated effects. Results showed that propolis supplementation significantly increased the levels of GSH (SMD = 3.16; 95% CI: 1.15, 5.18; I2 = 97.2%), GPX (SMD = 0.56; 95% CI: 0.07, 1.05; p = 0.025; I2 = 62.3%), and TAC (SMD = 3.26; 95% CI: 0.89, 5.62; I2 = 97.8%, p < 0.001). However, the effect of propolis on SOD was not significant (SMD = 0.05; 95% CI: -0.25, 0.34; I2 = 0.0%). Although the MDA concentration was not significantly decreased overall (SMD = -0.85, 95% CI: -1.70, 0.09; I2 = 93.3%), a significant decrease in MDA levels was observed at doses ≥1000 mg/day (SMD = -1.90; 95% CI: -2.97, -0.82; I2 = 86.4) and supplementation durations of less than 11 weeks (SMD = -1.56; 95% CI: -2.60, -0.51; I2 = 90.4). These results suggest that propolis is a safe supplement with a beneficial effect on GSH, GPX, and TAC levels and may be an effective adjunctive therapy for diseases where oxidative stress is a key factor in the etiology. However, further high-quality studies are necessary to make more precise and comprehensive recommendations given the limited number of studies, clinical diversity, and other limitations.

The effects of probiotics on VCAM-1 and ICAM-1: A systematic review and meta-analysis of randomized controlled trials.

BACKGROUND: We performed the present systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the effects of probiotics on intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) levels in adults. METHODS: A systematic search current to April 2022 was performed in MEDLINE, EMBASE, and Cochrane Database using relevant keywords to detect eligible articles. A random-effects model was used to estimate the standardized mean difference (SMD) and 95% confidence interval (95% CI). RESULTS: Six eligible trials were included in the final analysis. The pooled analysis revealed that there was a significant reduction in VCAM-1 from baseline to post-probiotic course with standardized mean difference [SMD: -0.66 ng/ml; 95% CI: -1.09, -0.23 ng/ml; P = 0.003]. The effects of probiotic intake on VCAM-1 were more pronounced when it was received via supplements [SMD: -0.61 ng/ml; 95% CI: -1.08, -0.14 ng/ml; P = 0.010], for 12 weeks [SMD: -0.60 ng/ml; 95% CI: -1.09, -0.12 ng/ml; P = 0.014] and when it was prescribed for individuals with metabolic syndrome [SMD: -0.79 ng/ml; 95% CI: -1.40, -0.19 ng/ml; P = 0.010]. Moreover, VCAM-1 levels were decreased in the subgroup of multispecies probiotic regiments [SMD: -0.71 ng/ml; 95% CI: -1.38, -0.04 ng/ml; P = 0.039]. CONCLUSION: Our study demonstrates potential beneficial effects of probiotics on VCAM-1 in adults. However, more larger-scale, long-time RCTs are needed to confirm the accurate effect of probiotics on endothelial dysfunction biomarkers.

Inositol supplementation and body mass index: A systematic review and meta-analysis of randomized clinical trials.

Background: Inositol is a sugar-alcohol and recognized as a key component of cell membrane phospholipids. It has crucial role in the cell signaling pathways and contribute to improving glycemic responses. Although some earlier studies have revealed the effect of inositol mediating glucose uptake by improving insulin sensitivity, the benefit of inositol supplementation in patients with overweight and obesity is not completely understood. This study aimed to assess the impact of inositol supplementation on body mass index (BMI) through a systematic review and meta-analysis of controlled clinical trials. Methods: A systematic search was performed to August 2021 in the following databases: PubMed-Medline, Embase, Web of Science and Scopus. Fifteen controlled clinical trials investigating the effect of inositol on adult's BMI were finally included in the study. A random-effects model was employed to estimate the effect size. Subgroup analysis was performed by dose, duration, age, type of inositol. Meta-regression was used to investigate presence of any linear relationship. Begg's and Egger's tests were carried out to detect small study effect. Results: The results of pooled analysis showed that inositol supplementation significantly decreased BMI scores (WMD = -0.41 kg/m2; 95% CI: -0.78, -0.04; p = 0.028). Subgroup analysis was performed to identify the source of heterogeneity among studies (I 2 = 73.9%, p < 0.001), demonstrating supplementation duration, baseline BMI, mean age of participants, type of inositol and dosage were potential sources of heterogeneity. The effect of intervention was more clinically significant in participants with polycystic ovary syndrome (PCOS) and overweight/obesity. Inositol in the form of myo-inositol (MI) had stronger effect on BMI reduction. Conclusion: The meta-analysis suggests that oral inositol supplementation has positive effect on BMI reduction. Inositol supplementation could be considered as an adjunct treatment to improve body mass index.

Effects of vitamin D supplementation on apolipoprotein A1 and B100 levels in adults: Systematic review and meta-analysis of controlled clinical trials.

Cardiovascular disease (CVD) is a leading cause of death around the world. According to the studies, apolipoproteins A1 and B100 play crucial role in CVD development and progression. Also, findings have indicated the positive role of vitamin D on these factors. Thus, we conducted the present meta-analysis of randomized controlled trials (RCTs) to demonstrate the impact of vitamin D supplementation on apolipoproteins A1 and B100 levels in adults. PubMed and Scopus databases and Google Scholar were searched up to 21 December 2020. Relevant articles were screened, extracted, and assessed for quality based on the Cochrane collaboration's risk of bias tool. Data analysis conducted by random-effect model and expressed by standardized mean difference (SMD). The heterogeneity between studies was assessed by I-squared (I2) test. Subgroups and sensitivity Analyses were also conducted. Seven RCTs were identified investigating the impact of vitamin D on Apo A1 levels and six on Apo B100 levels. The findings showed the insignificant effect of vitamin D supplementation on Apo A1 (SMD=0.26 mg/dL; 95% confidence interval (CI), -0.10, 0.61; P = 0.155) and Apo B100 (standardized mean difference (SMD)=-0.06 mg/dL; 95% CI, -0.24, 0.12; P = 0.530) in adults. There was a significant between-study heterogeneity in Apo A1 (I2=89.3%, P < 0.001) and Apo B100 (I2 = 57.1%, P = 0.030). However, significant increase in Apo A1 in daily dosage of vitamin D (SMD=0.56 mg/dL; 95% CI, 0.02, 1.11; P = 0.044) and ≤12 weeks of supplementation duration (SMD=0.71 mg/dL; 95% CI, 0.08, 1.34; P = 0.028) was observed. No significant effects of vitamin D on Apo A1 and Apo B100 levels after subgroup analysis by mean age, gender, study population, dosage and duration of study. Overall, daily vitamin D supplementation and ≤12 weeks of supplementation might have beneficial effects in increasing Apo A1 levels, however, future high-quality trials considering these a primary outcome are required.

Spirulina supplementation and anthropometric indices: A systematic review and meta-analysis of controlled clinical trials.

Obesity and overweight are associated with the burden of chronic diseases. The aim of the present meta-analysis is to determine the efficacy of spirulina in reducing of obesity indices. PubMed, Web of Science, Scopus, EMBASE and Cochrane library databases were searched up to November 2019. Randomized controlled trials comparing spirulina supplementation with a placebo or no treatment for anthropometric indices were included. Meta-analysis was performed using random-effects model. Subgroup analysis and meta-regression were carried out. Publication bias was evaluated using standard methods. Spirulina had ameliorative effects on weight (WMD = -1.85 Kg; 95% CI: -2.44, -1.26; p < .001; I2 = 82.4%, p < .001), and waist circumference (WMD = -1.09 cm; 95% CI: -2.16, -0.01; p = .046; I2 = 0.0%, p = .757) while no significant effect was shown on body mass index, even after sensitivity analysis (SMD = -0.53 Kg/m2 ; 95% CI: -1.25, 0.19; p = .149; I2 = 92.9%, p < .001); however, spirulina was effective in studies lasted for at least 12 weeks (SMD = -1.25 Kg/m2 ; 95% CI: -2.21, -0.28; p = .011; I2 = 90.8%, p < .001). Spirulina supplementation exerts beneficial effects on weight and waist circumference. The ameliorative effect of spirulina on body mass index was revealed in longer duration of supplementation.

The effects of N-acetylcysteine on inflammatory and oxidative stress biomarkers: A systematic review and meta-analysis of controlled clinical trials.

Prolonged inflammation could be considered as the leading cause of chronic diseases such as cardiovascular disorders, type two diabetes, and obesity. N-acetylcysteine (NAC) is considered an antioxidant. The present meta-analysis aims to determine the efficacy of NAC in alleviating inflammation and oxidative stress. PubMed-Medline, SCOPUS, Web of Science and Embase databases and Google Scholar were searched up to Nov 2019. Random effect analysis was used to perform meta-analysis. Subgroup analyses were carried out to find heterogeneity sources. Meta-regression analysis was used to explore linear relationship between effect size and variables. Trim and fill analysis were performed in case of the presence of publication bias. Quality assessment was performed using Cochrane Collaboration's tool. A total of 28 studies were included in meta-analysis. NAC significantly decreased malondialdehyde (MDA) (SMD = -1.44 µmol/L; 95% CI: -2.05, -0.84; P < 0.001), IL-8 (WMD = -2.56 pg/ml; 95% CI: -3.89, -1.23; P < 0.001) and homocysteine (WMD = -1.45 pg/ml; 95% CI: -2.74, -0.17; P = 0.027) levels. There were no significant effects of NAC supplementation on CRP (SMD = -0.1 g/L; 95% CI: -0.52, 0.32; P = 0.647), TNF- α (WMD = -0.2 pg/ml; 95% CI: -0.65, 0.25; P = 0.378) and IL-6 (WMD = -0.41 pg/ml; 95% CI: -1.15, 0.32; P = 0.270) levels. However, NAC effects were significant in ameliorating TNF-α and IL-6 using sensitivity analysis. NAC significantly decreased MDA, IL-8, and homocysteine levels. The effects of NAC on amending TNF-α and IL-6 levels were significant after sensitivity analysis. No significant change was observed on CRP levels.