1534-P: Associations of Total, Plant-Based, and Animal-Based Low-Carbohydrate Diets with Mortality in Individuals with Stage 3–4 CKM Syndrome

Introduction and Objective: Low-carbohydrate diets (LCDs) are widely recommended for glycemic control and cardiovascular risk control. However, among individuals with advanced cardiovascular-kidney-metabolic (CKM) syndrome, in whom dietary recommendations for diabetes, cardiovascular disease, and chronic kidney disease often conflict, the associations of different LCD patterns with mortality remain unclear. Methods: This study analyzed data from the NHANES (1999-2018) and the UK Biobank (UKB). Adults with CKM syndrome stage 3-4 were included. LCD scores were calculated based on the percentage of energy derived from macronutrients, and associations with mortality were assessed using multivariable Cox proportional hazards models. Results: Among individuals with CKM syndrome stage 3-4, after multivariable adjustment, the total low-carbohydrate diet (TLCD) score was not associated with all-cause mortality. Higher plant-based low-carbohydrate diet (PLCD) scores were associated with lower all-cause mortality in both cohorts. In the NHANES, the hazard ratios (95% CIs) for PLCD quartiles Q2-Q4 compared with Q1 were 0.88 (0.79-0.99), 0.92 (0.82-1.03), and 0.84 (0.74-0.94), respectively; in the UKB, the corresponding hazard ratios were 0.89 (0.81-0.99), 0.83 (0.75-0.91), and 0.86 (0.78-0.94). No significant associations were observed for animal-based low-carbohydrate diet (ALCD) scores. The PLCD score exhibited a nonlinear inverted J-shaped association with all-cause mortality, with the lowest risk observed at approximately the upper two-thirds of the total score range. Plant protein and plant fat intakes exhibited similar inverted J-shaped associations, whereas animal protein and animal fat showed J-shaped curves. Conclusion: Among individuals with CKM syndrome stage 3-4, higher PLCD scores were associated with lower all-cause mortality in a nonlinear manner while TLCD and ALCD scores were neutrally associated with all-cause mortality. Disclosure S. Shi: None. X. Xiong: None.