Prospective association between trans fatty acid intake and depressive symptoms: Results from the study of women's health across the nation.

Background: This prospective investigation examined relations between dietary trans fatty acid intake of women at midlife in baseline and prevalence of depressive symptoms 5 years later.

Methods: Women enrolled in the Study of Women's Health Across the Nation (SWAN) had measures of CES-D depression scores 5 years later and trans fatty acid intake at baseline. Logistic regression models were used to study prospective associations between trans fatty acid intake and depressive symptoms.

Results: In overall 2376 women, baseline trans fatty acid intake did not predict depressive symptoms (p = 0.139) in model 1 adjusting for total caloric intake. However, after additional adjustment for age, race/ethnicity, education, financial strain, physical activity, BMI, menopausal status, VMS, chronic stress and use of antidepressant in model 2, baseline trans fatty acid intake predicted depressive symptoms 5 years later. This association remained statistically significant when additional controlling for SHBG, testosterone and estradiol in fully adjusted model 3. The fully adjusted OR of depressive symptoms was 1.637 (1.087-2.467) in quartile 4 (the highest) versus quartile 1 (the lowest) of the trans fatty acid intake. Sensitivity analyses performed in women with baseline CES-D score <16 showed that this association remained statistically significant.

Limitations: Assessment of depression and trans fatty acid intake was based on a self-report scale.

Conclusions: Trans fatty acid intake is a predictor for depressive symptoms 5 years later in midlife women independent health and psychosocial profiles. This underlines the importance of targeting trans fatty acid in the prevention of major depression in midlife women.