Correlation Between β-cell Function And Insulin Resistance And Microalbuminuria In Type 2 Diabetic Islets

Purpose:We investigated the relationships of pancreatic β-cell function and insulin resistance with microalbuminuria in a cross-sectional study of patients with type 2 diabetes.Methods A total of 524 participants with type 2 diabetes were recruited in this cross-sectional study. All subjects’ height, weight, waist circunlstance, and blood pressure were measured. Venous blood samples were drawn to measure fasting plasma glucose(FPG), fasting lipids, glycated hemoglobin A1C(Hb A1c), fasting C-peptide(FPC). 24h-urine was collected to measure urinary albumin excretion rate(UAER). Homeostasis model assessment of pancreatic β-cell function(HOMA-B) and insulin resistance(HOMA-IR) were estimated using fasting plasma C-peptide. According to HOMA-B quartile, the subjects were divided into four groups, including q1 ~ q4. According to HOMA-IR, the subjects were also divided into four groups, including Q1 ~ Q4. We assessed the crude associations across quartiles of these data with demographic and clinical parameters using a nonparametric test for trend across ordered groups(nptrend using Stata software). Multivariable logistic regression analysis was performed to assess the relationships of pancreatic β-cell function and insulin resistance with microalbuminuria in patients with type 2 diabetes.Results Trend test showed that UAER gradually reduced with increase of HOMA-B(P = 0.035). With HOMA-IR increasing, UAER gradually increased(P = 0.016). Multivariable logistic regression analysis showed that subjects with the highest quartile of HOMA-B had lower possibility of microalbuminuria than patients with the lowest quartile of HOMA-B(Adjusted OR q 4 vs. q 1 = 0.45, 95% CI 0.23-0.85, P = 0.015). Subjects with the highest quartile of HOMA-IR had higher risk of microalbuminuria than those with the lowest quartile of HOMA-IR(Adjusted OR Q 4 vs. Q 1 = 1.85, 95% CI 1.01-3.42, P = 0.048).Conclusion Insulin resistance may be an independent risk factor of microalbuminuria in patients with type 2 diabetes, while better pancreatic β-cell function may be an independent protective factor of microalbuminuria for those patients.