Objective: To test whether depressive symptoms are related to subsequent C-reactive protein (CRP) levels and/or whether CRP levels are related to subsequent depressive symptoms in mid-life women. Methods: Women enrolled in the Study of Women's Health Across the Nation (SWAN) were followed for 7 years and had measures of CES-Depression scores and CRP seven times during the follow-up period. Women were pre- or early peri-menopausal at study entry and were of Caucasian, African American, Hispanic, Japanese, or Chinese race/ethnicity. Analyses were restricted to initially healthy women. Results: Longitudinal mixed linear regression models adjusting for age, race, site, time between exams, and outcome variable at year X showed that higher CES-D scores predicted higher subsequent CRP levels and vice versa over a 7-year period. Full multivariate models adjusting for body mass index, physical activity, medications, health conditions, and other covariates showed that higher CRP levels at year X predicted higher CES-D scores at year X + 1, p = 0.03. Higher depressive symptoms predicted higher subsequent CRP levels at marginally significant levels, p = 0.10. Conclusions: Higher CRP levels led to higher subsequent depressive symptoms, albeit the effect was small. The study demonstrates the importance of considering bi-directional relationships for depression and other psychosocial factors and risk for heart disease.
Bibliographical noteFunding Information:
The Study of Women’s Health Across the Nation (SWAN) has grant support from the National Institutes of Health (NIH), DHHS, through the National Institute on Aging (NIA), the National Institute of Nursing Research (NINR) and the NIH Office of Research on Women’s Health (ORWH) (Grants NR004061 ; AG012505 , AG012535 , AG012531 , AG012539 , AG012546 , AG012553 , AG012554 , AG012495 ). The content of this paper is solely the responsibility of the authors and does not necessarily represent the official views of the NIA, NINR, ORWH or the NIH.
- C-reactive protein