Association of Dietary Inflammatory Index (DII) and depression in the elderly over 55 years in Northern China: analysis of data from a multicentre, cohort study.

OBJECTIVES

Our study aimed to assess the association between the Dietary Inflammatory Index (DII) and depression in the elderly over 55 years in Northern China.

METHODS

We analysed the data of 2022 Chinese adults aged 55 and over from a community-based neurological disease cohort study from 2018 to 2019. A validated semiquantitative food frequency questionnaire was used to assess eating habits at the time of inclusion. Multiple logistic regression was used for analysis, and social demographics, lifestyle and health-related factors were adjusted.

RESULTS

Among the included population, the prevalence of depression was 23.39%. Mean (SD) and range of the DII in the included population were 1.70 (1.42) and -5.20 to +5.68. The risk of depression was significantly higher in participants in the most pro-inflammatory group (quartile 4) than in the participants in the most anti-inflammatory group (quartile 1) (OR 1.53; 1.37 to 1.82; p-trend=0.01). The subgroup analysis of body mass index (BMI) showed that there is a significant association between DII and the risk of depression in overweight and obese people (p＜0.05). The restricted cubic spline results show that the OR value of depression possesses an upward trend with the increase of the DII score.

CONCLUSIONS

Aged patients with depression present a higher potential for dietary inflammation. Pro-inflammatory diets might increase the risk of depressive symptoms. Further research in different populations is crucial to confirm the association between DII and depression.