The association of insulin resistance and C-reactive protein with urinary albumin excretion rate in patients with type 2 diabetes for 5 years

Objective To investigate the association of insulin resistance and C-reactive protein with urinary albumin excretion rate(UAER)in patients with type 2 diabetes for 5 years. Methods The subjects(674 cases with type 2 diabetes for 5 years)were divided into the normal albuminuria group (296 cases, UAER20 μg/min), microalbuminuria group (242 cases, UAER: 20~200 μg/min)and clinical albuminuria group(136 cases, UAER200 μg/min), according to UAER levels. Oral glucose tolerance test and insulin release test were performed.The insulin resistance index (ISI), area under the insulin curve and ratio of the area under insulin curve(AUCI/AUCG)were used to assess the insulin resistance(HOMA-IR)for each patient. The levels of hs-CRP, HbA1C, LDL-C, HDL-C, SCr and BUN were measured for analyzing the relationship between UREA and hs-CRP or insulin resistance. Results The ISI in normal albuminuria group was -3.67±0.53, which was significantly higher than those(-4.27±0.42 and -4.39± 0.47)in microalbuminuria group and clinical albuminuria group (P0.05). HOMA-IR in normal albuminuria group was 3.41± 0.56, which was significantly lower than those (3.88±0.42 and 3.97±0.52)in microalbuminuria group and clinical albuminuria group(P0.05). AUCI/AUCG in normal albuminuria group was 2.89±0.62 which was significantly lower than those(2.93±0.84 and 2.97±0.53)in microalbuminuria group and clinical albuminuria group (P0.05). There was positive correlation between UAER levels and hs-CRP levels (r=0.319,P0.05). Multiple stepwise regression analysis showed that UAER was positively correlated with diabetes progress, hs-CRP and AUCI/AUCG (β were 0.643, 0.148 and 0.219, respectively, P0.05). Conclusion The increase of UAER in T2DM patients with normal renal function for 5 years might be associated with the development of insulin resistance and the increase of hs-CRP level.