Increased resistin blood levels are not associated with insulin resistance in patients with renal disease.

BACKGROUND

Resistin is a newly discovered insulin inhibitor secreted by adipocytes. We explored the potential role of resistin in the pathophysiological process of insulin resistance encountered in patients with renal disease.

METHODS

Resistin blood concentrations, insulin sensitivity index (by intravenous glucose tolerance test), and glomerular filtration rate (GFR; by inulin clearance) were assessed in 30 male patients with immunoglobulin A glomerulonephritis in different stages of renal disease.

RESULTS

Patients with increased resistin blood concentrations had more advanced renal failure and were significantly older. Plasma resistin levels correlated significantly with GFR (r = -0.82; P < 0.0001), plasma homocysteine concentration (r = 0.68; P < 0.001), and age (r = 0.42; P = 0.05), but not with fasted plasma insulin (r = -0.34; P = 0.12), glucose (r = 0.25; P = 0.19), and leptin (r = -0.24; P = 0.21) concentrations; body mass index (r = -0.06; P = 0.75), waist-hip ratio (r = 0.09; P = 0.63), or insulin sensitivity (r = -0.05; P = 0.79). In multiple regression analysis, GFR was the only independent predictor of plasma resistin concentrations in renal patients (r = -0.812; P < 0.0001).

CONCLUSION

Resistin blood concentrations increase with progressive impairment of renal function. Thus, the kidney seems to be an important site of resistin elimination. However, the greater than 5-fold increase in resistin blood levels apparently is not associated with deterioration in insulin sensitivity in patients with renal disease.