Hormone Replacement Therapy and Adverse Outcomes in Women With Atrial Fibrillation

BACKGROUND AND PURPOSE: Hormone replacement therapy (HRT) use has been related to thromboembolism, but whether HRT increases adverse outcomes in females with atrial fibrillation is uncertain. METHODS: We used the Atrial Fibrillation Follow-Up Investigation of Rhythm Management (AFFIRM) trial data set that included 1594 women (39.3% of the population, mean age 71±8), of whom 376 (23.6%) were taking HRT at baseline. The primary end point, a composite of all-cause death, stroke, systemic/pulmonary embolism, and myocardial infarction, and secondary outcomes (ie, each individual end point) and major bleeding, were considered. RESULTS: HRT was not independently associated with the primary end point (hazard ratio=0.894; 95% confidence interval, 0.658-1.214; P=0.473) or any secondary outcome. Age (P<0.001), diabetes mellitus (P<0.001), previous stroke (P=0.011), and heart failure (P<0.001) predicted the primary end point. Lack of association between HRT and the primary end point was confirmed in a propensity score-matched control group (hazard ratio=0.966; 95% confidence interval, 0.663-1.409; P=0.858). CONCLUSIONS: HRT does not independently predict mortality, thromboembolism, or bleeding in a large cohort of women with atrial fibrillation.