The association between dietary quality index- international and metabolic risk factors in RaNCD cohort study

Non-communicable diseases (NCDs) are the leading cause of death around the world. The Dietary Quality Index-International (DQI-I) is one of the indicators that shows changes in diet and its association with NCDs. The aim of this study is to measure the association between the DQI-I and major metabolic risk factors.

This study is a cross-sectional study based on data collected in the first phase of the prospective cohort study on Ravansar non-communicable diseases (RaNCD). To perform clinical and biochemical tests such as lipid profile, blood glucose and liver enzymes, blood samples were collected using standard vacutainer blood collection techniques. Information from the food frequency questionnaire containing 118 food items was used to score each person's DQI-I. Binary logistic regression was used to determine the association between the DQI-I tertile and the metabolic risk factors. Linear regression was also used for the association between subgroups of DQI-I score and the metabolic risk factors.

The total number of subjects in this study was 7,115, with a mean age of 47.14 ± 8.29 years. Dietary quality was generally poor, with 37.03% in the lowest tertile. Men had better dietary quality than women. Anthropometric measures, blood pressure, triglycerides and blood glucose were lower in the lowest tertile of dietary quality. A one-unit increase in the total DQI-I resulted in a 0.19 decrease in total cholesterol. Higher dietary quality was associated with a 22% increased risk of high triglycerides, a 19% increased risk of low high-density density lipoprotein, a 5% decreased risk of elevated low-density lipoprotein, a 42% increased risk of high blood pressure, and a 99% increased risk of high fasting blood glucose. Higher dietary quality was also associated with a 33% increased risk of overweight/obesity.

The study found that participants had poor dietary quality, with some favorable metabolic outcomes in the lowest tertile, but concerning associations in the highest tertile, including increased risk for high triglycerides, blood pressure, and obesity. The complex associations suggest that balanced, multifaceted interventions are needed.