Impact of the women's health initiative trial results on hormone replacement therapy

Abstract

Study objective: To describe the impact of the results of the Women's Health Initiative (WHI) on hormone replacement therapy (HRT) discontinuation rates.

Design: Retrospective chart review.

Setting: University-based family medicine clinic.

Subjects: Ninety-eight postmenopausal women (aged 50-79 yrs) with an intact uterus who were receiving HRT.

Measurements and main results: Two study periods were defined: pre-WHI (July 9, 2001-January 9, 2002) and post-WHI (July 9, 2002-January 9, 2003). Patient demographics and HRT discontinuation or persistence data were collected. Seven women were eligible for only for pre-WHI, 13 only for post-WHI, and 78 were eligible for both groups based on HRT use during both time periods. Forty-two of the 78 women were randomized to the pre-WHI group and 36 to the post-WHI group to yield equal groups of 49 each. No significant demographic differences existed between the groups. Time-to-event analysis revealed an increased probability of HRT discontinuation after WHI versus before WHI (log-rank test, p<0.01). A subset of 85 women taking HRT 1 year before WHI were followed for 18 months. Discontinuation rates were 8% (7 of 85 patients) during the 12 months before WHI and 38% (30 of 78) during the 6 months after WHI, with 80% (24 of 30) of these patients discontinuing within 3 months.

Conclusion: Increased HRT discontinuation was temporally associated with release of WHI data, which implies that highly publicized, negative outcomes data can quickly influence pharmacotherapy decisions.