Renin–angiotensin system blockade for the risk of cancer and death

Introduction:The effects of renin–angiotensin system blockade with angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II type 1 receptor blockers (ARBs) on cancer remain inconsistent.Methods:We searched existing databases from 1960 to August 2015, for randomised controlled trials and observational studies (case–control studies and cohort studies) of ARB/ACEI therapy with a minimal one year of follow-up. Outcomes were incidence and mortality of cancer.Results:We included 14 randomised controlled trials and 17 observational studies of 3,957,725 participants (350,329 ARB/ACEI users). The users had a lower incidence of cancer in the observational studies (RR 0.82, 95% CI 0.73–0.93) but not in the randomised controlled trials (RR 1.00, 95% CI 0.92–1.08). The protection persisted for lung cancer (RR 0.85, 95% CI 0.75–0.97) but not for other sites of cancer. The relative risk of cancer associated with renin–angiotensin system blockade was reduced along with time of follow-up. Mortality reduction wi...