Association between the Dietary Inflammatory Index and Hypertension in Middle-Aged and Elderly population in China: Results from a nation-wide cross sectional study

Background: Evidence on the Association between Dietary Inflammatory Index and Risk of Hypertension among Chinese Population aged 45 and above Objective： To investigate the association between DII and hypertension in Chinese adults aged 45 years and above. Methods： Data was from the China Adults Chronic Diseases and Nutrition Surveillance (2015) for participants who were 45 years of age or above. The DII for each participant was determined through a combination of 3 day 24-hour dietary recall interviews and a food frequency questionnaire. Spatial analysis was employed to investigate the geographic distribution of DII in China. Furthermore, restricted cubic spline models and binary logistic regression analysis were used to assess the relationship between DII and hypertension. Results： A total of 39,282 middle-aged and elderly participants were included in the study, among whom 6,133 had hypertension. The DII scores of participants with hypertension were higher compared to those without hypertension (1.507 vs. 1.447, P = 0.003). There was a significant increasing trend in the proportion of hypertensive individuals as DII scores increase (P for trend = 0.004). Spatial analysis revealed a clear spatial correlation in the national distribution of DII scores (Moran I: 0.252, P = 0.001), with higher DII scores concentrated in the northwest region and lower DII scores concentrated in the southeast region. Restricted cubic spline models and binary logistic regression analysis demonstrated a positive association between DII and hypertension after adjusting for potential confounding factors. Conclusions： Dietary inflammatory index was positively associated with hypertension in Chinese adults aged 45 years and above, and dietary intervention might be a promising method in the prevention of hypertension.