Endothelial dysfunction in IDDM; Relation to plasma homocystein levels

This work has been designed to evaluate the relationship of plasma homocystein [HCY] levels to the presence and development of diabetic microvascular complications in IDDM. Plasma levels of homocystein and thrombomodulin [TM] markers of endothelial cell damage, were measured before and 3h after oral methionine loading in 45 IDDM patients and 25 healthy control subjects matched for sex and age. IDDM patients had higher pre-and postload plasma levels of homocystein than did healthy control subjects [15 vs 6.8 umol/l and 28 vs 13 umol/I, p<0.001]. Of 45 IDDM patients, 17 had plasma homocystein levels above the normal range [means +/- 2 S.D. of values obtained of the normal control group]. These IDDM patients with hyper homocysteinemia had higher plasm TM levels [66 vs 36.5 ng/ml p<0.001], higher albumin excretion rates [390 mg vs 110 mg/dl p<0.001], and a higher prevalence of late diabetic complications [nephropathy, 65 vs 30% Neuropathy 53 vs 39%, retinopathy, 70 vs 43% and macroangiopathy, 59 vs 30%] compared with IDDM patients with normal homocystein, hyperhomocysteinemia is common in nephropathic diabetic patients and may contribute to enhanced morbidity and mortality from cardiovascular diseases characteristically observed in IDDM patients with diabetic nephropathy