BACKGROUND - Insulin resistance has been noted in patients with chronic kidney disease (CKD). The determinants of insulin resistance have not been well-studied in CKD patients.
OBJECTIVE - The objective of this study was to examine the degree and determinants of insulin resistance in persons without diabetes but with stage 3-4 CKD.
DESIGN - Demographic characteristics, metabolic hormones, and inflammatory markers were measured in 95 nonobese stage 3-4 CKD patients without prior diagnosis of diabetes mellitus and 36 control subjects without CKD. The estimated glomerular filtration rate (eGFR) was measured by using the Modification of Diet in Renal Disease study equation. Insulin resistance was measured with the use of the homeostasis model assessment of insulin resistance (HOMA-IR).
RESULTS - After age and sex adjustments, HOMA-IR scores were significantly and positively correlated with body mass index (BMI) and percentage body fat. After control for age, race, adiponectin concentrations, sex, and eGFR in a multivariate regression model, BMI remained as the only significant predictor of insulin resistance (standardized regression coefficient = 0.55; P < 0.001). When substituted for BMI, percentage body fat also was an independent predictor of insulin resistance. The prevalence of abnormal HOMA did not differ significantly between CKD patients (98%) and BMI-matched control subjects (94%).
CONCLUSION - Whereas insulin resistance is highly prevalent in stage 3-4 CKD, the primary determinant of insulin resistance in this population is BMI, specifically, fat mass.