Diabetic nephropathy and cardiovascular diseases

Diabetic nephropathy is diagnosed either when persistent increase of urinary albumin excretion rate (UAER) above 30 mg/24h in a patient with diabetes was discovered (early or incipient nephropathy) or when UAER values are persistently elevated above 300 mg/24h (overt or clinical nephropathy). In both situations the additional criteria of presence of diabetic retinopathy and the absence of the evidence of other kidney or renal tract disease should be fulfilled. It was found that the excess of cardiovascular events and mortality occurs already in diabetic patients with persistent microalbuminuria, but is particularly evident in macroalbuminuric diabetic patients and results not only from end-stage renal failure (ESRF) but rather from cardiovascular disease (CVD), the latter mainly in type 2 diabetic patients. Several traditional risk factor for atherosclerosis has been identified in diabetic patients with micro- or macroalbuminuria including elevated blood pressure levels, dyslipidemia and procoagulatory state associated with endothelial dysfunction. Microalbuminuria is currently regarded as a marker of generalized endothelial damage, it reflects transvascular albumin leakage, now recognized as an early event in atherogenesis. Recently the association of microalbuminuria with the marker of chronic inflammation (C-reactive protein) and with increased production of vascular endothelial growth factor (VEGE) was described. Thus, multiple mechanisms are involved in the development and progression of cardiovascular complications both in micro- and macroalbuminuric diabetic patients and all these mechanisms should be regarded as the target for therapeutic intervention.