Longer Duration of Hormonal Contraceptive Use Predicts Better Cognitive Outcomes Later in Life

Background: The cognitive effects of postmenopausal hormone therapy (HT) have been studied extensively, but little is known about the relationship between premenopausal hormone use and cognition. Hormonal contraceptive use vs. nonuse may be a potential factor influencing cognitive processes in midlife. The aim of this study is to explore the effect of modification of hormone milieu through use of hormonal contraception in premenopausal women and midlife cognitive function. Methods: Subjects were 261 cognitively normal women, aged 40-65 (mean mu = 52), enrolled in the Wisconsin Registry for Alzheimer's Prevention. All women completed the Women's Health History Questionnaire and a self-report health history questionnaire and were administered a battery of neuropsychologic tests. Cognitive results were analyzed using summary scores for the domains of Verbal Ability, Visuo-spatial Ability, Working Memory, Verbal Learning & Memory, and Speed & Flexibility derived using a confirmatory factor analysis. Results: Hormonal contraceptive ever users performed significantly better than never users in the domains of Visuo-spatial Ability (mu = 0.75, 95% confidence interval [CI] 0.23-1.28, p = 0.005) and Speed & Flexibility (mu = 0.52, 95% CI -0.16-1.04, p = 0.007), with duration-dependent increases in performance, especially in ever users with >= 15 years of use. Conclusions: These data provide preliminary evidence that hormonal contraceptive use may influence cognitive outcomes, even years after use is discontinued. Hormonal contraceptive users scored better in domains of Visuo-spatial Ability and Speed & Flexibility than never users, with a duration-dependent trend. Further research is needed to explore the use of hormonal contraceptives to prevent or delay cognitive decline and to clarify the physiologic basis of this phenomenon.