Sex differences in erythrocyte fatty acid composition of first-diagnosed, drug-naïve patients with major depressive disorders

Abstract

Background: Since depression, sex hormones, and fatty acid status are interrelated, it is important to understand their relationships. In this study, we aimed to investigate sex differences in erythrocyte membrane fatty acid composition among first-diagnosed, drug-naïve patients with major depressive disorders. Methods: The study included 139 individuals with first-diagnosed, drug-naïve depression (male/female = 48/91) and 55 healthy controls (male/female = 24/31). The levels of erythrocyte membrane fatty acids were analyzed to compare the difference between males and females in both patients with depression and healthy controls, as well as to study their correlation with depressive symptoms. Results: In first-diagnosed, drug-naïve patients with major depressive disorders, sex disparities were observed in the levels of erythrocyte saturated fatty acids (SFAs) and n-6 PUFAs (such as C18:0, C20:4n6 and C22:4n6), where higher levels evident in females compared to in males. We found a noteworthy correlation between fatty acid levels and depressive symptoms, in which there is a significant association between female patients and depression but a weaker association between male patients and depression. Conclusion: Our findings demonstrate higher levels of n-6 PUFAs and SFAs in female patients with depression. The relationship between fatty acid composition and depressive symptoms was more prominent in females than males. These findings highlight the significance of considering sex as a crucial and interconnected factor in future investigations and potential adjunctive treatment for mood disorders by targeting fatty acid metabolism.

Keywords: erythrocyte membrane fatty acids; major depression disorder; n-3 PUFAs; n-6 PUFAs; sex differences.

FIGURE 1

Correlations between fatty acids and depression in the male (A) and female (B) AA, arachidonic acid; BDI, Beck Depression Inventory; DHA, docosahexaenoic acid; EPA, eicosapentaenoic acid; FAs, fatty acids; HAMA, Hamilton Anxiety Scale; HAMD, 24-item Hamilton Depression Rating Scale; MUFAs, monounsaturated fatty acids; PUFAs, polyunsaturated fatty acids; SFAs, saturated fatty acids; SAS, Self-Rating Anxiety Scale; UI, unsaturation index, *p < 0.05, **p < 0.01.

FIGURE 2

Association between fatty acids and depression in the multivariable model AA, arachidonic acid; BMI, body mass index; CI, confidence interval; PUFAs, polyunsaturated fatty acids.