Efficacy of treating hypertension in women

OBJECTIVE:To assess whether the relative and absolute benefit of hypertensi on treatment in women varies with age or lace. DESIGN: Systematic review of studies from 1966 to 1998 using MEDLINE, revie ws, and consultation with experts. Eleven randomized controlled trials of p harmacologic treatment of primary hypertension with cardiovascular morbidit y and mortality outcomes were selected, with a pooled population of 23,000 women. Relative risks were combined for each end point to form a summary ri sk ratio using meta-analytic techniques based on a random-effects model. Su mmary risk ratios were converted to numbers needed to treat (NNTs). Data we re dichotomized by age to approximate menopausal status (30 to 54 years, an d 55 years and older), and by race (white and African American). MAIN RESULTS: In women aged 55 years or older (90% white), hypertension tre atment resulted in a 38% risk reduction in fatal and nonfatal cerebrovascul ar events (95% confidence interval [CI] 27%, 47%; 5-year NNT 78), a 25% red uction in fatal and nonfatal cardiovascular events (95% CI 17%, 33%; 5-year NNT 58), and a 17% reduction in cardiovascular mortality (95% CI 3%, 29%; 5-year NNT 282), In women aged 30 to 54 years (79% white), hypertension tre atment resulted in a 41% risk reduction in fatal and nonfatal cerebrovascul ar events (95% CI 8%, 63%; 5-year NNT 264), and a 27% risk reduction in fat al, and nonfatal cardiovascular events (95% CI 4%, 44%: 5-year NNT 259). Hy pertension treatment in African-American women (mean age, 52 years) reduced the risk of fatal and nonfatal cerebrovascular events by 53% (95% CI 29% 6 9%; 5-year NNT 39), fatal and nonfatal cardiovascular events by 45% (95% CI 18%, 63%; 5-year NNT 21), fatal and nonfatal coronary events by 33% (95% C I 6%. 52%: 5-year NNT 48), and all-cause mortality by 34% (95% CI 14%, 49%; 5-year NNT 32). Analyses In white women aged 30 to 54 years did not show a ny statistically significant treatment benefit or harm. CONCLUSIONS: Hypertension treatment lowers the relative and absolute risk o f cardiovascular morbidity and mortality in women aged 55 years and older a nd in African-American women of all ages. A greater effort should be made t o increase awareness and treatment in these groups of women. Although relat ive risk reductions for cerebrovascular and cardiovascular events are simil ar for younger and older women, the NNT of younger women is at least 4 time s higher. Decisions about treatment of hypertension in younger white women should be influenced by the individual patient's absolute risk of cardiovas cular disease.