Relationship between dietary patterns and diabetic microvascular complications in patients with type 2 diabetes mellitus

OBJECTIVE: This study aimed to investigate the relationship between different dietary patterns and diabetic microvascular complications in patients with type 2 diabetes mellitus. PATIENTS AND METHODS: This study was conducted based on the Chinese Chronic Disease and its Risk Factor Surveillance System. A multi-stage stratified sampling method was used to randomly select two districts (Xinghualing District, Taiyuan City, and Yuzi District, Jinzhong City) and two counties (Huguan County, Changzhi City, and Jiang County, Yuncheng City) from the chronic disease surveillance sites in Shanxi Province to collect general information, dietary records, physical measurements, and laboratory tests. In total, 1,227 patients were enrolled according to the study criteria. Factor analysis was performed to construct six dietary patterns, and the relationship between dietary pattern scores and type 2 diabetic microvascular complications was analysed using binary logistic regression after correcting for confounders. RESULTS: (1) Regarding the prevalence of type 2 diabetic microvascular complications and dietary characteristics, the prevalence of microvascular complications in patients with type 2 diabetes mellitus was 55.3% and was higher in urban than in rural areas. The prevalence of diabetic kidney disease (DKD), diabetic retinopathy, and diabetic peripheral neuropathy (DPN) were 21.4%, 12.7%, and 38.0%, respectively. (2) Six dietary patterns were constructed, namely, 'animal protein', 'coarse grains and plant protein', 'nuts and fruits', 'refined grains and vegetables', 'dairy', and 'added sugars', with factor contributions of 15.42%, 9.99%, 8.23%, 8.16%, 7.56%, and 7.28% respectively, explaining 56.64% of the total dietary variation. (3) After adjusting for confounding variables, the results of binary logistic regression indicated that patients in the highest quartile of dietary pattern scores for 'nuts and fruits' experienced a 43.3% lower risk of DKD compared to those in the lowest quartile [odds ratio (OR) = 0.567; 95% confidence interval (CI), 0.359- 0.894; p < 0.001]. Similarly, patients in the highest quartile of dietary pattern scores for 'animal protein' had a 42.8% lower risk of DPN compared with those in the lowest quartile (OR = 0.572; 95% CI, 0.388-0.843; p < 0.05). CONCLUSIONS: The results of this study suggest that in patients with type 2 diabetes mellitus, a 'nuts and fruits' dietary pattern reduces the risk of DKD and an 'animal protein' dietary pattern reduces the risk of DPN.