Use of postmenopausal hormone replacement therapy: estimates from a nationally representative cohort study.

The objective of this study was to describe trends in the use of hormone replacement therapy (HRT) in the United States by demographic, life-style, and heart disease risk factors. Data were obtained from the Epidemiologic Followup Study to the First National Health and Nutrition Examination Survey, a nationally representative cohort followed from the mid-1970s until 1992. A total of 5,602 women who had become menopausal by their last follow-up interview were included. An estimated 45% of the cohort of menopausal US women 25-74 years of age in the early 1970s used HRT for at least one month and 20% continued use for 5 or more years. Between 1987 and 1992, as the younger members of the cohort became menopausal, the proportion of this cohort who had ever used HRT and used it for 5 or more years increased by 32% and 54%, respectively. A higher probability of HRT use was found among women who were white, who were more highly educated, and who lived in the West, or who had experienced a surgical menopause. Women who were overweight or who abstained from alcohol were less likely to use HRT. These data support the hypothesis that HRT use is associated with sociodemographic factors, and that women tend to discontinue use within several years.