Dietary manganese intake is inversely associated with depressive symptoms in midlife women: A cross-sectional study.

Background: To study the association of manganese intake from diet with depressive symptoms in midlife women.

Methods: Data for this cross-sectional study were retrieved from baseline assessment of the Study of Women's Health Across the Nation (SWAN). Linear regression, logistic regression and restricted cubic spline models were performed to examine the association of manganese intake with depressive symptoms.

Results: A total of 2993 midlife women aged 42-52 years were included in the present study. In premenopausal women, manganese intake was inversely associated with CES-D score and after adjustment for total caloric intake, age, race/ethnicity, education, income, financial strain, physical activity, BMI, vasomotor symptoms, chronic stress and use of antidepressant, estradiol, testosterone and sex hormone binding globulin using linear regression. The fully adjusted regression coefficient 95% confidence intervals (CIs) were -0.533 (-0.993, -0.074). Similarly, manganese intake was inversely associated with depressive symptoms (CES-D scores≥16) using logistic regression adjusted same confounders. The fully adjusted odds ratios (ORs) with 95% CI of depressive symptoms were 0.512 (0.287-0.913) in quartile 4 compared with quartile 1 for manganese intake. However, in early perimenopausal women, no statistically significant difference was observed between manganese intake and depressive symptoms after adjustment for same confounders that adjusted in premenopausal women.

Limitations: This was a cross-sectional study, limiting causal inferences. Assessment of CES-D was based on a self-report scale.

Conclusion: Manganese intake may be inversely associated with depression symptoms in premenopausal women, but not in early perimenopausal women.