Coronary heart disease and hormone replacement therapy after the menopause.

The discordance in coronary heart disease (CHD) outcome between randomized, controlled trials and observational studies of hormone replacement therapy (HRT) is likely the result of the dissimilar cohorts studied. This observation led to the formation of the timing hypothesis that benefits and risks of HRT depend upon age of HRT initiation and/or time of HRT initiation in relation to menopause. This hypothesis has been supported with data from large, randomized, controlled trials that have studied HRT and selective estrogen receptor modulators (SERMs) in the prevention of CHD. Initiation of HRT in women <60 years of age and/or within 10 years of menopause reduces both CHD and total mortality; SERMs have been shown to reduce CHD in women <60 years. What has become clear from the cumulated literature is that in young postmenopausal women who initiate HRT in close proximity to menopause, the adverse effects of HRT are rare and no greater than those of other commonly used pharmacological agents and that the primary prevention benefits for CHD are at least equivalent to those of other commonly used therapies. Additionally, the literature indicates that the duration of HRT confers greater CHD benefit especially in women <60 years who initiate therapy. The cumulated literature dispels misperceptions concerning HRT and CHD.