[An association between adiponectin and renal dysfunction in patients with type 2 diabetes mellitus]

Adiponectin is a hormone of adipose tissue produced exclusively by adipocytes. According to recent studies its serum concentrations are negatively associated with obesity and diabetes mellitus type 2 (DM). The aim of the study was to clarify the relationship between renal functions and serum adiponectin in patients suffering from diabetic nephropathy.

The serum adiponectin levels were investigated in 120 patients and 40 controls. Patients in the diabetic group were divided according to albumin excretion rate into three groups - with normoalbuminuria (AER - albumin excretion rate/24 hod < 30 mg/24 h), with microalbuminuria (AER 30 300 mg/24 h) and with macroalbuminuria (AER > 300 mg/24 h).

Serum adiponectin levels in diabetic group did not show any significant difference as compared with the control group. The highest concentrations of adiponectin were observed in patients with macroalbuminuria 24.22 ± 10.37 µg/ml (p < 0.0001) compared to those with normoalbuminuria and microalbuminuria, or control group, which was significant. Patients with normoalbuminuria 12.16 ± 5.3 µg/ml had the lowest concentrations of adiponectin. The univariate linear regression analysis revealed the negative correlation with BMI (r = -0.4, p < 0.0001) and glomerular filtration (r = -0.2, p < 0.05) and positive correlation with albuminuria (r = 0.5, p < 0.0001). Multiple linear regression confirmed that BMI and AER are independent predictive factors of adiponectin levels as well as that adiponectin and glomerular filtration are independent predictors of albuminuria.

The beginning and progress of diabetic nephropathy play probably one of the most important roles in increased synthesis and excretion of adiponectin to blood circulation by diabetic patients with overt diabetic nephropathy. Key words: diabetes mellitus type 2 - adiponectin - obesity - diabetic nephropathy.