Abstract
OBJECTIVE: We investigated whether low sex hormone concentrations are associated with depression in older women. STUDY DESIGN: This was a cross-sectional study of Australian women, aged at least 70 years, not taking medications modulating sex hormone levels. Associations between hormones, measured by liquid chromatography-tandem mass spectrometry, and depression were examined by logistic regression adjusted for potential confounders. MAIN OUTCOME MEASURES: The primary outcome was a Center for Epidemiologic Studies Depression score >10, designated as 'depression', with an expanded definition that included anti-depressant use as a secondary outcome. RESULTS: For the 5535 participants in the analysis, median age 74.0 years (interquartile range 71.7-77.7), depression prevalence was 5.8 % (95 % CI 5.2-6.4 %). In the adjusted models, a statistically significantly greater likelihood of depression was seen for women with testosterone and oestrone blood concentrations in quartile 1 compared with quartiles 2-4 (odds ratio 1.33, 95 % CI 1.04 to 1.70, p = 0.022; and 1.37, 95 % CI 1.06 to 1.78, p = 0.017, respectively). For the expanded definition, the odds ratios for the lowest testosterone and oestrone quartile compared with other quartiles were 1.47 (95 % CI 1.24 to 1.75, p < 0.001) and 1.31 (95 % CI 1.09 to 1.58, p < 0.001), respectively. A significant association for low DHEA was seen only for the expanded definition of depression (1.36, 95 % CI 1.13 to 1.64, p = 0.001). Receiver operating characteristic curves showed that the contribution of each sex hormone to the likelihood of depression was small. CONCLUSIONS: Amongst older women not taking medications that influence sex hormone concentrations, low testosterone and oestrone levels are associated with a greater likelihood of depression, but the effects are small. TRIAL REGISTRATION: International Standard Randomized Controlled Trial Number Register (ISRCTN83772183) and clinicaltrials.gov (NCT01038583).