Hormone Replacement Therapy: Changing Guidelines, Changing Practice

Abstract

In the past decade our knowledge about the benefits and risks of hormone replacement therapy (HRT) has evolved substantially.  This paper reviews these changes and their impact on published clinical practice guidelines.  In the early 1990s, HRT was strongly recommended to all postmenopausal women for short-term use in the treatment of menopausal symptoms, and for long-term use in the prevention and treatment of osteoporosis and the prevention of cardiovascular disease.  The risk of breast cancer associated with HRT was considered small enough to be of little consequence in comparison to its purported benefits.  Data from three large RCTs were published during the late 1990s and early 2000s - the PEPI trial, the HERS trial, and the WHI trial.  In summary, these trials have shown increases in breast cancer (9 per 10,000 postmenopausal women per year) and cardiovascular events (7 coronary artery events and 8 strokes per 10,000 postmenopausal women per year) that may not be balanced by the decreases in menopausal symptoms and osteoporotic fractures (57 fewer total fractures per 10,000 postmenopausal women per year) in women taking HRT.  These findings have led to changes in clinical practice guidelines for HRT use.  Current guidelines recommend against the use of HRT solely for the primary or secondary prevention of cardiovascular disease, and caution against its use for the sole purpose of osteoporosis prevention or treatment.  Short-term relief of menopausal symptoms remains a relatively acceptable indication for HRT, however any prescription of HRT should be accompanied by a detalied discussion of its potential risks and benefits.