Metabolic Syndrome Trajectories and Objective Physical Performance in Mid-to-Early Late Life: The Study of Women's Health Across the Nation (SWAN)

Abstract

Background: Little is known about how adverse, midlife metabolic profiles affect future physical functioning. We hypothesized that a higher number of midlife metabolic syndrome (MetS) components are associated with poorer physical performance in early old age for multiethnic women.

Methods: MetS status from 1996 to 2011 (8 visits) and objective physical performance in 2015/2016 (Short Physical Performance Battery [SPPB; 0-12], 40-foot walk [meter/second], 4-meter gait speed [meter/second], chair stands [seconds], stair climb [seconds]) were assessed in the Study of Women's Health Across the Nation (SWAN; n = 1722; age 65.4 ± 2.7 years; 26.9% African American, 10.1% Chinese, 9.8% Japanese, 5.5% Hispanic). Poisson latent class growth modeling identified MetS component trajectory groups: none (23.9%), 1 = low-MetS (28.7%), 2 = mid-MetS (30.9%), and ≥3 = high-MetS (16.5%). Adjusted linear regression related MetS groups to physical performance outcomes.

Results: High-MetS versus none had higher body mass index, pain, financial strain, and lower physical activity and self-reported health (p < .0001). Compared with White, African American and Hispanic women were more likely to be in the high-MetS groups and had worse physical functioning along with Chinese women (SPPB, chair stand, stair climb, and gait speed-not Hispanic). After adjustments, high-MetS versus none demonstrated significantly worse 40-ft walk (β: -0.08; 95% CI: -0.13, -0.03), gait speed (β: -0.09; 95% CI: -0.15, -0.02), SPPB (β: -0.79; 95% CI: -1.15, -0.44), and chair stands (β: 0.69; 95% CI: 0.09, 1.28), but no difference in stair climb.

Conclusions: Midlife MetS groups were related to poor physical performance in early old age multiethnic women. Midlife management of metabolic function may improve physical performance later in life.

Keywords: Longitudinal; Metabolic; Physical functional performance; Racial disparities; Successful aging.