Association between dietary patterns and depressive symptom based on reduced rank regression in people aged 55 and above in 4 provinces of China

OBJECTIVE To investigate the dietary patterns related to depressive symptoms based on reduced rank regression in people aged 55 and above in 4 provinces of China and the degree of association between this dietary pattern and depressive symptoms. METHODS Stratified, multi-stage, cluster and random sampling method was used to collect personal information such as demographic characteristics, behavioral lifestyles, disease history and medicine use in Chinese aged 55 and above who participated in the baseline survey of "Community-based Cohort Study on Nervous System Diseases" project conducted in 2018 and 2019 in Hebei, Zhejiang, Shaanxi and Hunan Provinces. Food frequency questionnaire was used to obtain dietary data. Depressive symptom was assessed by geriatric depression scale with a cut-off of 11. Participants who have incomplete demographic information, dietary data or scores of geriatric depression scale, and those whose intake frequency of each food-group >99. 5% were excluded. A total of 11 497 participants, 43. 1% of whom were male, were involved in this study with average age of(67. 3±7. 6) years. The reduced rank regression method was used to extract depressive symptoms-related dietary patterns by gender, and the degree of association between dietary patterns and depressive symptom was analyzed by logistic regression. RESULTS Among males, the depressive symptoms-related dietary pattern was characterized by the higher intake frequency of fried flour-made food, meat, processed meat, animal offal, and preserved eggs, and the lower intake frequency of liquid milk/milk power/cheese, fresh eggs(except preserved eggs) and nut. Among females, the depressive symptoms-related dietary pattern was characterized by the higher intake frequency of fried flour-made food, meat, processed meat, animal offal and preserved eggs, and the lower intake frequency of coarse cereals, fruits, liquid milk/milk power/cheese and fresh eggs(except preserved eggs). The highest quartile group of the dietary pattern score had a significantly higher risk of depressive symptom than the lowest quartile group(OR=3. 498, 95% CI 2. 624-4. 663, P<0. 001 for males; OR=3. 853, 95% CI 3. 002-4. 944, P<0. 001 for females). CONCLUSION The depressive symptoms-related dietary pattern is characterized by the higher intake frequency of fried flour-made food, meat, processed meat, animal offal and preserved eggs, and the lower intake frequency of liquid milk/milk power/cheese and fresh eggs(except preserved eggs) in the Chinese aged 55 and above. The score of this dietary pattern is significantly positively correlated with depressive symptom.