Are depressive symptoms associated with cancer screening and cancer stage at diagnosis among postmenopausal women? The Women's Health Initiative observational cohort.

BACKGROUND: Women with depressive symptoms may use preventive services less frequently and experience poorer health outcomes. We investigated the association of depressive symptoms with breast and colorectal cancer screening rates and stage of cancer among a cohort of postmenopausal women.
METHODS: In The Women's Health Initiative Observational Study, 93,676 women were followed on average for 7.6 years. Depressive symptoms were measured at baseline and at 3 years using the 6-item scale from the Center for Epidemiological Studies Depression scale (CES-D). We calculated a cancer screening rate expressed as a proportion of the years that women were current with recommended cancer screening over the number of follow-up visits in the study. Breast and colorectal cancers were staged based on Surveillance, Epidemiology and End Results (SEER) classification.
RESULTS: At baseline, 15.8% (12,621) women were positive for depressive symptoms, and 6.9% (4,777) were positive at both baseline screening and at 3 years. The overall average screening rate was 71% for breast cancer and 53% for colorectal cancer. The breast cancer screening rate was 1.5% (CI 0.9%-2.0%) lower among women who reported depressive symptoms at baseline than among those who did not. Depressive symptoms were not a predictor for colorectal cancer screening. Stage of breast and colorectal cancer was not found to be associated with depressive symptoms after adjusting for covariates.
CONCLUSIONS: Among a healthy and self-motivated cohort of women, self-reported depressive symptoms were associated with lower rates of screening mammography but not with colorectal cancer screening.