A Longitudinal Investigation of Race, Socioeconomic Status, and Psychosocial Mediators of Allostatic Load in Midlife Women: Findings From the Study of Women's Health Across the Nation

Objectives: This research sought to assess racial and socioeconomic status (SES) differences in level and change in allostatic load (AL) over time in midlife women and to test whether psychosocial factors mediate these relationships. These factors were discrimination, perceived stress, and hostility. Methods: Longitudinal data obtained from the Study of Women's Health Across the Nation were used (n = 2063; mean age at baseline = 46.0 years). Latent growth curve models evaluated the impact of demographic, menopausal, and psychosocial variables on level and change in AL for 8 years. Results: Direct effects: high levels of discrimination and hostility significantly predicted higher AL (path coefficients = 0.05 and 0.05, respectively). High perceived stress significantly predicted a faster rate of increase of AL (path coefficient = 0.06). Racial and SES differentials were present, with African American race (path coefficient = 0.23), low income (path coefficient = -0.15), and low education (path coefficient = -0.08) significantly predicting high AL level. Indirect effects: significant indirect effects were found for African American race, less income, and lower education through higher discrimination, perceived stress, and hostility on level and rate of AL. Conclusions: This was one of the first studies that investigated AL over multiple periods, and results supported AL as a cumulative phenomenon, affected by multiple psychosocial and demographic factors. The results suggest the complex ways in which race, SES, and psychosocial factors operate to influence AL.