Letters Section Editor: Robert M. Golub, MD, Senior Editor.
To the Editor: In their sex-specific meta-analysis of aspirin in the primary prevention of cardiovascular disease, Dr Berger and colleagues1 found results similar to the meta-analysis we performed as part of the primary report of the Women's Health Study.2 However, meta-analyses can hide important clinical effects—in this case, the evidence of effect modification by age. In the Women's Health Study, the most consistent benefit of aspirin was observed among women aged 65 years or older, a group who comprised only 10% of the study population yet had almost one third of the total cardiovascular events.
Ridker PM, Cook NR, Buring JE. Use of Aspirin as Primary Prevention of Cardiovascular Events. JAMA. 2006;296(4):391-392. doi:10.1001/jama.296.4.391-a