Difference in association of carbohydrate intake with all-cause mortality between middle-aged and older Korean adults with and without diabetes mellitus: A prospective study

Background & Aims The relationship between diet and health, particularly the role of carbohydrates, has been extensively studied. However, carbohydrate intake based on individual health conditions remains unclear. Here, we aimed to investigate whether the association between carbohydrate intake and all-cause mortality varied between individuals with and without diabetes mellitus (DM). Methods This prospective cohort study used data from the Korean Genome and Epidemiology Study (KoGES). Overall, 143,050 participants were included, with 10.1% having DM. Dietary intake was assessed using a semiquantitative food frequency questionnaire. Cox proportional hazards regression models were used to assess the association between carbohydrate intake and mortality after adjusting for confounders. Results The study showed that 5,436 deaths occurred during the median follow-up period of 10.1 years. A significant interaction between carbohydrate intake and DM was observed in the study population (interaction p=0.061). Higher carbohydrate intake proportion was associated with an increased risk of all-cause mortality among individuals with DM (adjusted hazard ratio [HR], p-value =1.10 [1.01–1.20], p=0.032). Conversely, no association was observed between the proportion of carbohydrate intake and all-cause mortality in participants without DM. Additionally, both total sugar and added sugar intakes were associated with an increased risk of all-cause mortality in participants with DM (adjusted HR, p-value = 1.02 [1.01–1.04], p<0.001 and 1.18 [1.13–1.24], p<0.001). Conclusions High carbohydrate (%) and added sugar intake were associated with an increased mortality risk in individuals with DM. Reducing intake and opting for healthy carbohydrates to mitigate mortality risk may be beneficial for individuals with DM, particularly when compared with the general population.