Microinflammation is a common risk factor for progression of nephropathy and atherosclerosis in Japanese patients with type 2 diabetes

Aim: This study aimed to evaluate the change of serum levels of proinflammatory molecules in patients with type 2 diabetes and clarify the involvement of these molecules in diabetic nephropathy and atherosclerosis. Methods: Sixty-six Japanese type 2 diabetic patients (T2DM) and 39 healthy control subjects were enrolled. We assessed clinical parameters, urinary albumin excretion rate (AER), brachial-ankle pulse wave velocity (baPWV), intima media thickness (IMT) and serum levels of proinflammatory molecules. Results: Serum levels of IL-6, IP-10 and MCP-1 were significantly higher in T2DM than in control subjects. In T2DM, serum levels of high-sensitivity (hs) CRP, IP-10, hsTNF-α, VCAM-1 and E-selectin were positively correlated with AER. Serum levels of IP-10, hsTNF-α and VCAM-1 were positively correlated with baPWV. Serum levels of hsCRP, IL-6, IP-10 and hsTNF-α were positively correlated with IMT. Multiple linear regression analysis revealed that serum levels of hsTNF-α were independently associated with AER (β=0.235, P=0.038) and serum levels of IP-10 were independently associated with baPWV (β=0.209, P=0.047) and IMT (β=0.303, P=0.032). Conclusion: Our results suggest that low-grade inflammation, microinflammation, may be a common risk factor for diabetic nephropathy and atherosclerosis in Japanese type 2 diabetic patients.