The cardiovascular safety of aromatase inhibitors and tamoxifen in post-menopausal women with breast cancer: A systematic review and meta-analysis of randomized controlled trials.

1573Background: The cardiovascular safety of aromatase inhibitors (AIs) in the treatment of breast cancer is controversial, with meta-analyses of randomized controlled trials (RCTs) reporting an increased risk of cardiovascular events with these drugs when compared with tamoxifen. However, it is unclear if this observed risk is real or the result of a cardioprotective effect of tamoxifen. We conducted a systematic review and meta-analysis using data from adjuvant, extended-adjuvant, and placebo-controlled breast cancer trials. Methods: We systematically searched PubMed, Embase (OVID), Cochrane CENTRAL, WHO International Clinical Trials Registry Platform, and clinicaltrials.gov from inception to March 2015 for all RCTs comparing AIs to tamoxifen, AIs to placebo or no-treatment, or tamoxifen to placebo or no-treatment in the adjuvant or extended adjuvant setting. We extracted all the cardiovascular endpoints reported in these RCTs, and study-specific relative risks were pooled using DerSimonian and Laird ra...