Relationship between circulating irisin, renal function and body composition in type 2 diabetes

Aims: Chronic kidney disease (CKD) secondary to type 2 diabetes mellitus (T2DM) is associated with multifaceted energy dysmetabolism. We aim to study the relationship between renal function, body composition and irisin, the recently identified myokine which is involved in energy regulation, in T2DM. Methods: Circulating irisin and body composition were measured in 365 T2DM subjects across a wide range of renal function. Results: Circulating irisin was significantly decreased in T2DM with renal insufficiency (77.4 +/- 13.7 ng/ml in T2DM with eGFR >= 60 ml/min/1.73 m(2) versus 72.5 +/- 14.9 ng/ml in those with eGFR < 60 ml/min/1.73 m(2), p = 0.001) and the reduction in irisin was most pronounced in stage 5 CKD patients. In T2DM with preserved renal function, irisin was correlated with age (r = -0.242, p = 0.001) and pulse pressure (r = -0.188, p = 0.002). Among those with renal insufficiency, irisin was correlated with BMI (r = 0.171, p = 0.022), fat mass (r = 0.191, p = 0.013), percentage of fat mass (r = 0.210, p = 0.007) and eGFR (r = 0.171, p = 0.020). Multivariate linear regression models revealed that variations in circulating irisin were mainly attributable to eGFR and age in T2DM with and without renal impairment, respectively. Conclusion: Our observations suggest that the level of circulating irisin may be associated with renal function in T2DM. The role of reduced irisin in energy dysmetabolism in diabetic patients with renal insufficiency deserves further investigation. (C) 2014 Elsevier Inc. All rights reserved.