Usefulness of metabolic score for insulin resistance index in estimating the risk of mildly reduced estimate glomerular filtration rate: a cross-sectional study of rural population in China

OBJECTIVES: This study aimed to reveal the association between metabolic score for insulin resistance (MetS-IR) and the risk of mildly decreased estimated glomerular filtration rate (eGFR), and explore the evaluation effect of MetS-IR on the progress of eGFR decline. STUDY DESIGN: A cross-sectional study. SETTING AND PARTICIPANTS: A total of 11 956 rural participants (aged ≥35 years) from northeastern China were enrolled in the study. After excluding the subjects whose data were not integrated or who met the exclusion criteria, we finally obtained 11 042 participants in the present study. MAIN OUTCOME MEASURES: Mildly decreased eGFR was defined as 60–90 mL/min/1.73 m(2). RESULTS: The prevalence of mildly decreased eGFR in the general population was 36.9%. After adjustment of covariates, each SD increment of MetS-IR could bring 26.3% additional risk of mildly decreased eGFR (OR: 1.263, 95% CI: 1.066 to 1.497, p=0.007). When MetS-IR was classified into four levels by quartile, we observed participants in the top level had 3.032-fold risk of mildly decreased eGFR (OR: 3.032, 95% CI: 1.841 to 4.991, p<0.001) compared with those from the bottom level. Further, we found the participants with higher MetS-IR score were more likely to aggravate into a worse renal state which presented as higher risk of accelerated decline of eGFR, by additional 28.3% risk in whole participants (OR: 1.283, 95% CI: 1.150 to 1.430, p<0.001) and 41.9% in men (OR: 1.419, 95% CI: 1.183 to 1.701, p<0.001). CONCLUSION: High MetS-IR was associated with high risk of mildly reduced eGFR and often accompanied by a high risk of accelerated decline in eGFR. Hence, we believed MetS-IR was a suitable indicator to evaluate the risk of early-stage renal dysfunction.