Erythrocytes polyunsaturated fatty acids mediate relationship between dietary patterns and depression.

Abstract

Background: This study aimed to examine the association between depression and dietary patterns via the intermediary role of erythrocytes polyunsaturated fatty acids (PUFA). Methods: In this individually matched case-control study, the dietary patterns were extracted for 330 individuals using factor analysis. Furthermore, erythrocyte PUFAs including n-3 and n-6 were assessed using a GC-Mass spectrometry analytical method for 84 people. Depression was diagnosed using the criteria mentioned in the Diagnostic and Statistical Manual of Mental Disorders. The dietary patterns were also extracted using a valid and reliable semi-quantitative food frequency questionnaire. Results: The findings showed that healthy dietary patterns were related to the risk of depression (P=0.01, odds ratio (OR)=0.31, 95% confidence interval (CI): 0.14-0.68) by the increase of ratio n-3 /n-6 PUFA (p≤0.03) and decrease of ratio n-6 /n-3 PUFA (p≤0.005). Moreover, the unhealthy dietary patterns were associated with the risk of depression (P=0.02, OR=2.7, 95%CI: 1.25-5.9) by the decrease of ratio n-3/n-6 PUFA (p≤0.03) and increase of ratio n-6/n-3 PUFA (p≤0.001). Conclusion: Based on the results, the type of dietary pattern is related to the risk of depression considering the changes in n-3 and n-6 PUFA as well as the ratio of n-3 to n-6 as the mediator variables. Of course, further studies are required in this area.