The association between Dietary Approaches to Stop Hypertension and incidence of chronic kidney disease in adults: the Tehran Lipid and Glucose Study

Background. This study was conducted to examine the association of adherence to the Dietary Approaches to Stop Hypertension (DASH)-style diet with incident chronic kidney disease (CKD) among an Iranian population. Methods. We followed-up 1630 participants (50.5% women, mean age: 42.8 years) of the Tehran Lipid and Glucose Study for 6.1 years, who were initially free of CKD. Baseline diet was assessed using a valid and reliable 168-item food frequency questionnaire. A DASH-style diet, based on scoring eight components (fruits, vegetables, whole grains, nuts and legumes, low-fat dairy, red and processed meats, sweetened beverages and sodium) was used. Estimated glomerular filtration rate (eGFR) was calculated using the Modification of Diet in Renal Disease Study equation and CKD was defined as eGFR < 60 mL/min/1.73 m(2). Odds ratio (OR) using multivariable logistic regression was reported for the association of incident CKD with DASH-style diet score. Results. The incidence of CKD among those in the top quintile of the DASH-style diet was 30%, 18% lower than those in the bottom quintile. After controlling for age, sex, smoking, total energy intake, body mass index, eGFR, triglycerides, physical activity, hypertension and diabetes, adherence to the DASH-style diet was found to be inversely associated with incident CKD (OR: 0.41; 95% confidence interval: 0.24-0.70). In addition, higher scores of fruits, whole grains, nuts and legumes, sweetened beverages and sodium were inversely associated with incidence of CKD. Conclusion. Results revealed that after 6.1 years of follow-up, adherence to the DASH-style diet was associated with a lower risk of incident CKD among adults.