Association between percent body fat and the risk of prediabetes among Chinese adults: a 5-years longitudinal cohort study

This study aimed to explore the influence of percent body fat (PBF) on the risk of developing prediabetes among Chinese individuals, given the limited evidence on this relationship. We conducted a retrospective cohort study involving 185,586 Chinese adults. We applied Cox proportional hazards regression models, cubic spline functions, and smooth curve fitting to analyze the relationship between initial PBF and the likelihood of prediabetes, focusing on its nonlinear connection. We conducted various sensitivity and subgroup analyses to strengthen our results. After adjusting for covariates, we found a positive correlation between PBF and the risk of prediabetes (HR = 1.13, 95% CI: 1.12-1.15, p < 0.0001). Moreover, a nonlinear correlation was identified between PBF and the likelihood of prediabetes, with a turning point at 29.5. On the left side of the turning point, the hazard ratio was 1.01 (95% CI: 0.99-1.03, p = 0.4128), while on the right side, it was 1.52 (95% CI: 1.45-1.59, p < 0.0001). Furthermore, sensitivity and subgroup analyses reaffirmed the robustness of these findings. Our research identified a nonlinear relationship between PBF and the development of prediabetes in the Chinese population, marked by a turning point at 29.5. Lowering PBF below 29.5 may reduce the risk of developing prediabetes.