Macrovascular complications are the main cause of mortality in type 1 diabetes mellitus (T1DM). The purpose of this study was to clarify the presence of early vascular changes and to assess the risk factors of macrovascular complications in young adults with T1DM diagnosed in childhood and adolescence.

Seventy-two patients (23.9±2.4 years) with T1 DM diagnosed before 18 years of age and twenty normal controls were included. The incidence of hypertension, dyslipidemia, and other risk factors of macrovascular complication were reviewed. Flow-mediated vasodilation (FMD) and mean intima-media thickness (IMT) measured by ultrasound were compared between patients and control subjects, and their correlations with macrovascular risk factors were analyzed.

Of the 72 patients, 32 (44.4%) had hypertension. The proportions of maleness ( P =0.03) and mean body mass index ( P =0.04) were higher in the hypertensive patients than in normotensive patients. Thirty-one (N=69, 44.9%) patients had dyslipidemia and LDL-cholesterol was positively correlated with mean HbA1c (r=0.32, P =0.008) and total daily insulin dose (r=0.27, P =0.02). The mean IMT was significantly higher in patients than in control subjects (0.43±0.06 mm vs 0.39±0.06 mm, P =0.03). There was no difference in the value of FMD between patients and controls, but the duration of the disease after pubertal onset was negatively correlated with FMD (r=-0.34, P =0.01).

Hypertension, dyslipidemia and atherosclerotic vascular change were observed in young adults with T1DM diagnosed during childhood and adolescence; this strongly suggests that meticulous screening of macrovascular complications and control of their risk factors should be conducted.