Gain in adiposity across 15 years is associated with reduced gray matter volume in healthy women.

Objective: To test whether current gray matter volume (GMV) covaried with previously obtained longitudinal measures of weight gain-as assessed by increases in body mass index (BMI)-among otherwise healthy postmenopausal women. Cross-sectional results indicate that reduced GMV may be associated with excess body weight.

Methods: Demographic, biometric, and behavioral measures were obtained from 48 women as part of the Pittsburgh Healthy Women Study, a longitudinal epidemiological investigation initiated between 1983 and 1984. In 2005 and 2006, these women took part in a brain imaging protocol.

Results: Premenopausal BMI and a priori chosen confounding variables, including the number of years post menopause, an aggregate measure of perceived life stress spanning a 20-year period, resting blood pressure, total cerebral volume, and severity of white matter hyperintensities (a suspected indicator of aging-related silent cerebrovascular disease), explained approximately 22% of variance in total GMV. An additional 15% of the variance was uniquely explained by the change in BMI between pre- and postmenopausal longitudinal assessments, such that an increase in BMI predicted a greater reduction in GMV.

Conclusions: An increase in BMI during the menopausal transition and beyond is associated with reduced GMV among otherwise healthy women.