Carotid atherosclerosis in adolescents and young adults with IDDM. Relation to urinary endothelin, albumin, free cortisol, and other factors.

OBJECTIVE

To investigate 1) alterations of carotid intimal-plus-medial thickness (IMT) in subjects with IDDM and 2) the relation of IMT to indexes of diabetic angiopathy and to risk factors of atherosclerosis.

METHODS

IMT was assessed by ultrasound B-mode imaging in 39 subjects with IDDM (23 male, 16 female young adults aged 17.5 +/- 5.2 years, diabetes duration 8.8 +/- 5.9) and in 22 control subjects (healthy siblings of the IDDM subjects) of comparable age. Urinary endothelin (UET1) and urinary free cortisol (UFC) were determined by radioammunoassay (RIA), urinary albumin by nephelometry, HbA1c by high-performance liquid chromatography (HPLC), and plasma renin by immunoradiometric assay (IRMA).

RESULTS

The IMT values were greater in IDDM subjects than in control subjects (0.49 +/- 0.1 mm, 0.44 +/- 0.09 mm, respectively; P = 0.048) and greater in IDDM male subjects than in control male subjects (0.52 +/- 0.09 and 0.44 +/- 0.06 mm, respectively; P = 0.015), with no difference between IDDM and control female subjects. The IMT values were greater in diabetic male subjects than in female subjects (0.52 +/- 0.09 and 0.45 +/- 0.1 mm, respectively; P = 0.017). In IDDM subjects, but not in control subjects, there was a positive correlation of IMT to urinary albumin (P = 0.008), systolic blood pressure (P = 0.023), UET1 (P = 0.016), UFC (P = 0.002), and BMI (P = 0.021). Multiple regression analysis demonstrated that in IDDM subjects the variable that interacts independently with IMT was the BMI (P = 0.001).

CONCLUSIONS

IMT, an index of atherosclerosis (macroangiopathy), is increased in IDDM subjects quite early (already in adolescence), and it is positively related to urinary albumin, UET1, blood pressure, and UFC.