HealthDay News — Aspirin may not be effective for primary prevention of cardiovascular disease and cancer mortality, according to research published online Nov. 21 in Family Practice.
Frank Moriarty, Ph.D., from the Royal College of Surgeons in Dublin, and Mark H. Ebell, M.D., from the University of Georgia in Athens, compared the benefits and harms of aspirin for primary prevention before (1978 to 2002) and after (2005 onward) widespread use of statins and screening for colorectal cancer.
The researchers found that for older versus newer studies, the relative risks for vascular outcomes were 0.89 (95 percent confidence interval [CI], 0.83 to 0.95) versus 0.93 (0.86 to 0.99) for major adverse cardiovascular events; 1.73 (1.11 to 2.72) versus 1.06 (0.66 to 1.70) for fatal hemorrhagic stroke; 0.86 (0.74 to 1.00) versus 0.86 (0.75 to 0.98) for any ischemic stroke; 0.84 (0.77 to 0.92) versus 0.88 (0.77 to 1.00) for any myocardial infarction; and 0.79 (0.71 to 0.88) versus 0.94 (0.83 to 1.08) for nonfatal myocardial infarction. In newer studies, there was no significant decrease observed for cancer mortality (relative risk, 1.11; 95 percent CI, 0.92 to 1.34). Significant increases were seen in major hemorrhage (older studies, relative risk, 1.48 [95 percent CI, 1.25 to 1.76] versus newer studies, relative risk, 1.37 [95 percent CI, 1.24 to 1.53]).
“In a modern era characterized by widespread statin use and population-wide cancer screening, aspirin no longer reduces the absolute risk of cancer death or myocardial infarction when given as primary prevention,” the authors write.