Relationship of HOMA-IR with chronic kidney disease in diabetic and non-diabetic Chinese populations: findings from the REACTION study

Background: Chronic kidney disease (CKD) affects 8.2% of China's population and is a major global health concern. While insulin resistance (IR) is linked to CKD, the relationship between insulin resistance (HOMA-IR) and CKD risk remains unclear, especially in diabetic and non-diabetic populations. Methods: This cross-sectional study analyzed data from 32,055 Chinese adults in the REACTION study. Logistic regression and generalized additive models assessed the association between HOMA-IR and CKD risk in diabetic (DM) and non-diabetic (Non-DM) populations, with nonlinear relationships explored using two-piecewise logistic regression. Results: The overall CKD prevalence was 16.09%(95% CI: 15.68%-16.49%). In the Non-DM group, HOMA-IR was positively associated with CKD risk (OR = 1.037, 95% CI: 1.010-1.066, P = 0.008), while no significant association was found in the DM group (OR = 0.991, 95% CI: 0.952-1.032, P = 0.667). Both groups showed an n-shaped relationship, with inflection points at HOMA-IR values of 2.581 (Non-DM) and 2.587 (DM). Below these thresholds, CKD risk increased with HOMA-IR; above them, risk decreased. Conclusion: Elevated HOMA-IR is independently associated with an increased risk of CKD in non-diabetic individuals, whereas this association is not significant in diabetic patients. These findings strongly highlight the clinical value of HOMA-IR as an early predictor of CKD risk, particularly in non-diabetic populations, emphasizing the importance of monitoring insulin resistance for early risk stratification and tailored management.