Adaptation and validity assessment of a diet quality index for patients with type 2 diabetes

Purpose As diet quality indices (DQI) are likely to be influenced by disease background, adapting the existing indices for each disease is crucial. No study has been adapted a DQI for patients with type 2 diabetes. We aimed to adapt healthy eating index and assess its validity for Iranian patients with type 2 diabetes mellitus (T2DM). Methods In this cross-sectional study, the analysis was conducted on 489 adults with T2DM. We adapted HEI and assessed its validity using construct validity. Construct validity was assessed using a 168-item semi-quantitative food-frequency questionnaire (FFQ). General linear model was used to assess associations between adapted HEI scores and demographic characteristics, anthropometric indices, physical activity and food and nutrient intakes. Results Adapted HEI were examined on 489 subjects (163 men and 326 women). Findings showed that in older subjects the mean adapted HEI score was greater than the younger ones. However, it was significant only in women (p = 0.01). Women with higher education level obtained the greater score (p < 0.001). The greatest mean score of the adapted HEI score in men was related to non-smokers. The mean score in both genders were raised following the increase in physical activity level (p < 0.05). Moreover, a reduction in the mean score of adapted HEI was observed in men with higher BMI compared to those with the lower one (p = 0.001). Conclusion Adapted HEI could successfully discriminate diet quality in patients with T2DM. Older and high-educated women were adhered greatly to high quality diets. The adapted DQI linked with greater physical activity level and non-smokers diabetic men with lower BMI.