Total homocysteine in patients with type 1 diabetes

Our aim was to study the presence of moderate hyperhomocysteinemia, a risk factor for premature cardiovascular disease, its modifying vitamin factors (folates, vitamins B12 and B6), and lipid risk factors in juvenile type 1 diabetes.

A total of 91 patients with type 1 diabetes (46 girls and 45 boys) were studied, with ages ranging from 11 to 18 years, a duration of diabetes from 1 to 15 years, and in pubertal development (stages III, IV, V). In all patients, cholesterol, triglycerides, HDL and LDL cholesterol, lipoprotein(a), folates, cobalamin, vitamin B6, and total homocysteine were determined by specific assays. Microalbuminuria, defined as a ratio of albumin/creatinine >3 mg/mmol creatinine, was analyzed in the first morning specimen.

Plasma total homocysteine (tHcy) concentrations were not different in the 91 diabetic children (median [range]) (11-15 years, 6.1 micromol/l [3.2-9.6]; 16-18 years, 7.3 micromol/l [3.9-12]) compared with the control group (11-15 years, 6.6 micromol/l [4.4-10.8]; 16-18 years, 8.1 micromol/l [4.6-11.3]). No significant differences were found in tHcy values in relation to the metabolic control of the disease as assessed by glycohemoglobin values, the duration of disease, alterations in fundus oculi, or presence of lymphocytic thyroiditis. A positive correlation was found between tHcy and plasma creatinine in type 1 diabetic patients that might be related with the increase in muscle mass. There was a negative correlation between tHcy and serum folate (P<0.001) and vitamin B12 (P<0.05), but not with vitamin B6 levels. No significant correlations were found between tHcy and the lipid parameters.

Hyperhomocysteinemia was not detected in adolescents with type 1 diabetes.