Pathogenesis of diabetic macro- and microangiopathy.

Epidemiological investigations reveal that we must expect a rapid increase in cases of diabetes mellitus in the next few years. As a result, vascular complications in the form of macro- and microangiopathy are also expected to arise more frequently. A classical example of macroangiopathy is coronary arteriosclerosis, microangiopathy is exemplified by diabetic nephropathy. In patients suffering from diabetes, macroangiopathy manifests as atherosclerosis like in nondiabetic patients, characterized by formation of plaques that follows in stages but with an accelerated course due to the different risk factors, especially hyper- and dyslipidemia, with cumulative effects. Thus, atherosclerosis in diabetes begins earlier, is more markedly pronounced and progresses more rapidly. The pathogenetic concept is based on an endothelial lesion that occurs as a result of a diabetes-specific, endothelium-damaging parameters. In case of diabetic microangiopathy histologically characterized by a progressive glomerulosclerosis, arteriolosclerosis and interstitial fibrosis hyperglycemia, along with its consecutive and complex processes that induce matrix increase, is considered to be the primary pathogenetically relevant factor involved. Insulin resistance seems to be the major common denominator at the center of both diabetic macroangiopathy and microangiopathy.