Association between erythrocyte levels of n-3 polyunsaturated fatty acids and depression in postmenopausal women using or not using hormone therapy

Key Findings

Epidemiologic and clinical studies have suggested that hormone therapy provides an antidepressant benefit in postmenopausal women. Blood levels of n-3 PUFAs were observed to be higher in postmenopausal women using HT, which could be due to estrogen’s enhancement of the conversion of alpha-linolenic acid into EPA and DHA. In the present study, there were no significant associations of serum levels of cytokines, including IL-6, IL-10, Il-1B and TNF-a, between depressed and non-depressed women using and not using HT. The findings suggest that the beneficial effect of n-3 PUFAs on depression is greater in postmenopausal women using HT than in those not using HT. Low dose of HT combined with n-3 PUFAs might be one of the possible alternatives for using HT alone to reduce the risk for HT-associated diseases including breast cancer and cardiovascular disease.

Abstract

Objective: Epidemiologic and clinical studies have suggested that hormone therapy (HT) and n-3 polyunsaturated fatty acids (PUFAs), such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), exert antidepressant effects through regulation of the serotonergic pathway. The present study was conducted to evaluate the hypothesis that erythrocyte levels of n-3 PUFAs and depression were negatively associated in postmenopausal women, particularly those using HT. Methods: A total of 214 postmenopausal women were divided into groups defined by depression and HT status.   Depression was defined as a Beck Depression Inventory score of at least 14, and the types and durations of HT were obtained from medical records. Results: Erythrocyte levels of EPA, docosapentaenoic acid (DPA), DHA, omega-3 index, total n-3 PUFA, and arachidonic acid were significantly higher in women using HT than in those not using HT. There were significant negative correlations between depression and erythrocyte levels of alpha-linolenic acid and total n-3 PUFA in women using HT. Multivariate-adjusted logistic regression analysis also showed that depression was negatively associated with the erythrocyte levels of alpha-linolenic acid and DHA only in women using HT. Conclusions: Negative associations between erythrocyte levels of n-3 PUFAs and depression were found in Korean postmenopausal women using HT but not in those not using HT, suggesting a synergistic effect of HT and n-3 PUFAs on depression.