A longitudinal assessment of lipids in youth with type 1 diabetes.

Background: Type 1 diabetes and dyslipidemia are known risk factors for cardiovascular disease (CVD), but the relationship between lipid levels in youth with type 1 diabetes and future CVD remains unknown. Objective: To characterize lipid levels and CVD risk factors over time in youth with type 1 diabetes. Subjects: The study included adolescents with type 1 diabetes (12-25 yr) with a minimum of 3-yr follow-up. Methods: A longitudinal prospective, observational study of 46 youth with type 1 diabetes was performed. Fasting lipid profiles, A1C, and body mass index (BMI) were measured every 6 months for at least 3 yr (median 4.2 yr). Low-density lipoprotein (LDL)-cholesterol, total cholesterol (TC), and triglycerides (TG) were divided into categorical variables. Results: At baseline, median age was 14.3 yr, mean diabetes duration was 6.4 +/- 3.8 yr, mean A1C was 8.1 +/- 1.0%, and median BMI z-score was 0.92. Fifty percent of subjects had LDL levels < 100 mg/dL (< 2.6 mmol/L) at study onset. After adjusting for confounding factors, increasing BMI z-score [beta = 0.2, 95% confidence interval (CI ) = 0.03-0.38, p = 0.03] and increasing A1C (beta = 0.18, 95% CI = 0.08-0.29, p = 0.001) were associated with increasing LDL category over time. Non-Hispanic ethnicity (beta = 0.45, 95% CI = 0.12-0.79, p = 0.008) and family history of stroke (beta = 0.38, 95% CI = 0.04-0.72, p = 0.03) were also associated with increasing LDL category. Age, diabetes duration, and tobacco exposure were not related to change in LDL. Increasing A1C was associated with increases in TG (beta = 18.1, 95% CI = 2.3-33.9, p = 0.03), TC (beta = 20.3, 95% CI = 9.0-31.5, p < 0.0001), and LDL (beta = 13.4, 95% CI = 3.17- 23.6, p = 0.01). Conclusion: Glycemic control and BMI are modifiable risk factors for dyslipidemia in youth with type 1 diabetes.