Management of stable coronary artery disease and atrial fibrillation with anti-thrombotic therapy: A systematic review and meta-analysis.

INTRODUCTION: Long term management of patients with stable coronary artery disease of >1 year after myocardial infarction (MI) or percutaneous coronary intervention and atrial fibrillation is unclear. Current guidelines recommend using oral anti-coagulation (OAC) alone although the recommendation is weak and there is low quality evidence. Two new randomized control trials (RCTs) were published recently. We conducted an updated meta-analysis to evaluate the effect of these studies on patient outcomes. OBJECTIVE: To conduct a systematic review and meta-analysis of published RCTs and observational studies to compare OAC alone versus OAC plus single anti-platelet therapy. METHODS: Electronic searches were conducted using appropriate terms from 3 databases. Relevant studies included. Data extracted and analysis were performed using STATA. MEASUREMENTS: Summary statistics were pooled and measured for primary and secondary outcomes of both treatment arms. MAIN RESULTS: Eight studies involving 10,120 patients were included for the analysis. Five thousand two hundred thirty-seven patients were on combination therapy while 4883 were on OAC alone. There was no statistically significant difference in the primary outcome of major adverse cardiac events (hazard ratio [HR] 1.067; 95% confidence interval [CI] 0.912-1.249; P value .417). There was no statistically significant difference even in the measured secondary outcomes namely all cause mortality (HR 1.048; 95% CI 0.830-1.323; P value .695), cardiovascular mortality (HR 0.863; 95% CI 0.593-1.254; P value .439). However, we found statistically significant difference between the 2 groups in the incidence of MI with higher incidence in mono therapy group (HR 1.229; 95% CI 1.011-1.495; P value .039) and higher incidence of major bleeding in the combination therapy group in the subgroup analysis (HR 0.649; 95% CI 0.464-0.907; P value .011). CONCLUSION: We found no reduction of major adverse cardiac event between combination therapy and mono therapy. Although mono therapy showed increased risk of major bleeding overall, subgroup analysis of the RCTs showed increased risk of major bleeding in the combination therapy group. MI was higher in the mono therapy group compared to the combination therapy group, however this outcome was not reproducible in the subgroup analysis of the RCTs.

The role of vitamin D supplementation for primary prevention of cancer: meta-analysis of randomized controlled trials.

Background: In the USA cancer is the second leading cause of mortality, as such, primary prevention of cancer is a major public health concern. Vitamin D supplementation has been studied as a primary prevention method for multiple diseases including cardiovascular disease, osteoporosis, diabetes mellitus and cancer. The role of Vitamin D as primary prevention of cancer is still controversial. With fast emergence of large randomized controlled trials (RCTs) in that regards, we aimed to evaluate the efficacy of Vitamin D supplementation as primary prophylaxis for cancer. Methods: A comprehensive electronic database search was conducted for all RCTs where comparison of Vitamin D supplementation versus placebo for the prevention of any type of disease with at least 3 years of Vitamin D supplementation was used and where cancer incidence or mortality was reported. The primary outcome was cancer-related mortality and cancer incidence. We calculated risk ratios (RRs) and 95% confidence intervals (CIs) using a random-effects model at the longest follow-up. Results: We included 10 RCTs with 79,055 total patients, mean age of 68.07 years, a female percentage of 78.02% and a minimum follow-up of 4 years and more. Vitamin D was associated with significant reduction of cancer-related mortality compared with placebo (RR 0.87; 95% CI: 0.79-0.96; P = 0.05: I2 = 0%). Compared with placebo, Vitamin D was not associated with significant reduction of cancer incidence (RR: 0.96; 95% CI: 0.86-1.07; P = 0.46; I2 = 31%). Conclusion: With inclusion of studies, which did not primarily examine vitamin D for the purpose of preventing cancer or reducing cancer mortality our meta-analysis highlights that the use of vitamin D supplementation for primary prevention of cancer is encouraged as it does possibly decrease cancer-related mortality once cancer is diagnosed; however, it has no role or effect on cancer incidence.