Clinical Question:
Is aspirin beneficial in the primary prevention of adverse cardiovascular
events in both women and men?
Bottom Line:
For women and men, aspirin therapy reduced the risk of a composite of
cardiovascular events due to its effect on reducing the risk of ischemic
stroke in women and MI in men. Aspirin significantly increased the risk of
bleeding to a similar degree among women and men.
Reference:
Berger JS, Roncaglioni MC, Avanzini F, Pangrazzi I, Tognoni G, Brown DL.
Aspirin for the primary prevention of cardiovascular events in women and
men. A sex-specific meta-analysis of randomized controlled trials. JAMA
2006;295:306-13.
Study Design:
Meta-analysis (randomized controlled trials)
Synopsis:
Aspirin therapy reduces the risk of cardiovascular disease in adults who are
at increased risk. However, it is unclear if women derive the same benefit
as men. To determine if the benefits and risks of aspirin treatment in the
primary prevention of cardiovascular disease vary by sex. MEDLINE and the
Cochrane Central Register of Controlled Trials databases (1966 to March
2005), bibliographies of retrieved trials, and reports presented at major
scientific meetings. Eligible studies were prospective, randomized
controlled trials of aspirin therapy in participants without cardiovascular
disease that reported data on myocardial infarction (MI), stroke, and
cardiovascular mortality. Six trials with a total of 95 456 individuals were
identified; 3 trials included only men, 1 included only women, and 2
included both sexes. Studies were reviewed to determine the number of
patients randomized, mean duration of follow-up, and end points (a composite
of cardiovascular events [nonfatal MI, nonfatal stroke, and cardiovascular
mortality], each of these individual components separately, and major
bleeding). Among 51,342 women, there were 1285 major cardiovascular events:
625 strokes, 469 MIs, and 364 cardiovascular deaths. Aspirin therapy was
associated with a significant 12% reduction in cardiovascular events (odds
ratio [OR], 0.88; 95% confidence interval [CI], 0.79-0.99; P = .03) and a
17% reduction in stroke (OR, 0.83; 95% CI, 0.70-0.97; P = .02), which was a
reflection of reduced rates of ischemic stroke (OR, 0.76; 95% CI, 0.63-0.93;
P = .008). There was no significant effect on MI or cardiovascular
mortality. Among 44,114 men, there were 2047 major cardiovascular events:
597 strokes, 1023 MIs, and 776 cardiovascular deaths. Aspirin therapy was
associated with a significant 14% reduction in cardiovascular events (OR,
0.86; 95% CI, 0.78-0.94; P = .01) and a 32% reduction in MI (OR, 0.68; 95%
CI, 0.54-0.86; P = .001). There was no significant effect on stroke or
cardiovascular mortality. Aspirin treatment increased the risk of bleeding
in women (OR, 1.68; 95% CI, 1.13-2.52; P = .01) and in men (OR, 1.72; 95%
CI, 1.35-2.20; P<.001). |