Association of C-reactive protein and hyperuricemia with diabetic nephropathy in Chinese type 2 diabetic patients

To investigate the relationship of micro-albuminuria with C-reactive protein (CRP) and hyperuricemia in Chinese patients with type 2 diabetes. All patients with type 2 diabetes, 40 years old and over were recruited consecutively from diabetic clinics at a medical center. Serum lipid, creatinine, uric acid, CRP, HbA_1C and urinary albumin concentration were measured. A total of 515 patients, aged 60.3 ± 10.7 years were recruited and the number (rate) of micro- and macro-albuminuria were 109 (21.2%) and 55 (10.7%). The prevalence of micro-albuminuria for the quartiles of CRP levels demonstrated a meaningful trend of increases between groups from 17.4, 21.1, 30.3, and 31.2% (P trend = 0.002). Besides, the median CRP concentrations was significantly higher in the patients with micro- and macro-albuminuria than those with non-albuminuria. Stepwise logistic regression analysis revealed that CRP was significantly associated with abnormal albuminuria (OR = 1.36, 95% CI = 1.12–1.64, P = 0.002). After excluding those subjects with angiotensin-converting enzyme inhibitors/angiotension II receptor blockers or/and statin usage, the observed relationship between serum CRP levels and albuminuria was still persistent (OR = 1.61, 95% CI = 1.24–2.08, P < 0.001). In addition, hyperuricemia were significantly associated with abnormal albuminuria in the patients without diuretics, uricosuric agents or alcohol usage. Both serum CRP levels and hyperuricemia were significantly related to the presence of albuminuria in patients with diabetes. In addition, Chinese type 2 diabetic patients with serum CRP levels in the lower range as other ethnic groups can lead to the development of micro-albuminuria.