Abstract P608: Dynamic Changes in Dietary Guidelines Adherence and Its Association With All-Cause Mortality Among Middle-Aged Chinese: A Longitudinal Study From the China Health and Nutrition Survey

Abstract

Background: The traditional approach to evaluating dietary quality is based on the achievement of the recommended intakes for each food group, which may overlook the achievement of correct relative proportions between food groups. We propose a “Dietary Adherence Score (DAS)” to assess the degree of similarity between subjects' diets and those recommended in the Chinese Dietary Guidelines (CDG). Furthermore, it is important to incorporate the time-dependent nature of dietary quality into the mortality prediction. Aim: To investigate the association between long-term changes in adherence to the CDG and all-cause mortality. Method: The study included 4533 participants aged 30-60 from the China Health and Nutrition Survey study with a median follow-up of 6.9 years. Intakes from 10 food groups were collected in 5 survey rounds from 2004 to 2015. We calculated the Euclidean distance between the intake of each food and the CDG-recommended intake, and then summed all the foods as DAS. Mortality was assessed in 2015. The latent class trajectory modeling was used to identify 3 classes of participants with distinct longitudinal trajectories of DAS during the follow-up period. The Cox proportional hazard model was used to assess the risk of all-cause mortality in the 3 classes of people. Risk factors for death and a traditional measure of diet quality, the Alternative Healthy Eating Index (AHEI), were adjusted in the models. Result: There were 187 deaths overall. Participants in the first class identified had consistently low and decreasing DAS levels (coefficient= -0.020) over their lifetime, compared with a hazard ratio (HR) of 4.4 (95% confidence interval [CI]: 1.5, 12.7) for participants with consistently high and increasing DAS levels (coefficient= 0.008). Those with moderate DAS had an HR of 3.0 (95% CI: 1.1, 8.4). The effect of DAS was independent of AHEI. Conclusion: People with consistently high adherence to CDG-recommended dietary patterns had a significantly lower mortality risk. DAS is a promising method to assess diet quality.