The association of menopause status with physical function: the Study of Women's Health Across the Nation

Objective: The aim of this study was to determine whether postmenopause status is associated with self-reported limitations in physical function. Methods: The Study of Women's Health Across the Nation is a multisite, multiethnic, longitudinal study of midlife women. Women aged 45 to 57 years (N = 2,566) completed the physical function scale of the Medical Outcomes Study Short-Form 36 on visit 4 (2000-2001). Scores created a three-category variable of physical function limitations: none (86-100), moderate (51-85), and substantial (0-50). In the Study of Women's Health Across the Nation, menopause status is a five-category list variable based on menstrual bleeding patterns and gynecological surgery. Premenopausal and perimenopausal women using hormones (n = 284) or missing physical function scores (n = 46) were excluded. Multinomial logistic regression was used to relate physical function and menopause status after adjustment for age, ethnicity, site, education, body mass index (BMI), and self-reported diabetes, hypertension, arthritis, depressive symptoms, smoking, and hormone use among postmenopausal women. Results: Of 2,236 women, 8% were premenopausal, 51% were early perimenopausal, 12% were late perimenopausal, 24% were naturally postmenopausal, and 5% were surgically postmenopausal. In the full model, substantial limitations in physical function were higher in postmenopausal women, whether naturally postmenopausal (odds ratio, 3.82; 95% CI, 1.46-10.0) or surgically postmenopausal (odds ratio, 3.54; 95% CI, 1.15-10.84), than in premenopausal women. These associations were attenuated by higher BMI and depressive symptoms but remained significant. Moderate limitations in physical function were not significantly related to menopause status. Conclusions: Women experiencing surgical or naturally occurring postmenopause report greater limitations in physical function compared with premenopausal women, independent of age and only partly explained by higher BMI and depressive symptoms. This suggests that physiological changes in menopause could contribute directly to limitations in physical function.