Several clinical trials have evaluated the effects of lipid-lowering
medications on coronary heart disease (CHD). Many of the trials have not included
enough women to allow sex-specific analyses or have not reported results in
To assess and synthesize the evidence regarding drug treatment of hyperlipidemia
for the prevention of CHD events in women and to conduct a meta-analysis of
the effect of drug treatment on mortality.
We searched MEDLINE, the Cochrane Database, and the Database of Abstracts
of Reviews of Effectiveness for articles published from 1966 through December
2003. We reviewed reference lists of articles and consulted content experts.
Study Selection and Data Extraction
Studies of outpatients that had a treatment duration of at least 1 year,
assessed the impact of lipid lowering on clinical outcomes, and reported results
by sex were included. Outcomes evaluated were total mortality, CHD mortality,
nonfatal myocardial infarction, revascularization, and total CHD events. Summary
estimates of the relative risks (RRs) with therapy were calculated using a
random-effects model for patients with and without a previous history of cardiovascular
Thirteen studies were included. Six trials included a total of 11 435
women without cardiovascular disease and assessed the effects of lipid-lowering
medications. Lipid lowering did not reduce total mortality (RR, 0.95; 95%
confidence interval [CI], 0.62-1.46), CHD mortality (RR, 1.07; 95% CI, 0.47-2.40),
nonfatal myocardial infarction (RR, 0.61; 95% CI, 0.22-1.68), revascularization
(RR, 0.87; 95% CI, 0.33-2.31), or CHD events (RR, 0.87; 95% CI, 0.69-1.09).
However, some analyses were limited by too few CHD events in the available
trials. Eight trials included 8272 women with cardiovascular disease and assessed
the effects of lipid-lowering medications. Lipid lowering did not reduce total
mortality in women with cardiovascular disease (RR, 1.00; 95% CI, 0.77-1.29).
However, lipid lowering reduced CHD mortality (RR, 0.74; 95% CI, 0.55-1.00),
nonfatal myocardial infarction (RR, 0.71; 95% CI, 0.58-0.87), revascularization
(RR, 0.70; 95% CI, 0.55-0.89), and total CHD events (RR, 0.80; CI, 0.71-0.91).
For women without cardiovascular disease, lipid lowering does not affect
total or CHD mortality. Lipid lowering may reduce CHD events, but current
evidence is insufficient to determine this conclusively. For women with known
cardiovascular disease, treatment of hyperlipidemia is effective in reducing
CHD events, CHD mortality, nonfatal myocardial infarction, and revascularization,
but it does not affect total mortality.