Obesity epidemic in childhood/adolescence may influence the mode of presentation of diabetes in conditions usually diagnosed in lean people like T1DM and MODY. The aim of our study was to identify clinical parameters useful for distinguishing betweeen obese patients with T1DM (T1DMob) and patients with T2DM with onset in adolescence (T2DMad). For this study, overweight/obesity was defined as BMI ≥ 95th centile for age and sex according to BMI calculator for child and teen of CDC. We compared 60 T1DMob patients (at least one T1DM autoab with high titer) with 36 patients with T2DMad (negative to T1DM autoabs). Patients with T2DMad and a parent with diabetes were considered as possibly being MODY, and excluded. We evaluated sex, ethnicity, birth weight, and age, plasma glucose, HbA1c, C-peptide, Cholesterol, HDL/Cholest., triglycerides (TG), and blood pressure (BP) at diabetes onset. Mean age at diagnosis was lower in T1DMob (9.7±3.0) than T2DMad (13.9±2.4) (p<0.001), while fasting plasma glucose (20±10.5 vs. 16.2±8.6 mmol/L respectively) and HbA1c were not statistically different. C-peptide (1.0±0.9 vs. 4.0±3.5 ng/ml, p<0.001), TG (104.9±77.9 vs. 284.5±297.6, p<0.001), total Cholesterol (159.9±35.9 vs. 194.5±30.2, mg/dl, p=0.006), systolic BP (111.3±11.2 vs. 126.6±14.3 mm/Hg, p<0.001) were lower, and HDL/Cholest. (48.7±23 vs. 32.3±10.1, p<0.001) was higher in T1DMob. In 17 pubertal T1DMob patients (age at onset 13.2±2.2) C-peptide (1.5±1, p=0.001), TG (115.7±81.7, p=0.005), systolic BP (116.9±6.6, p=0.04) were still lower, and HDL/Cholest. (57.0±35.3, p=0.001) still higher than T2DMad. TG/HDL ratio, another index of insulin resistance (IR) was higher (11.2±15.2 vs. 2.6±2.2, p=0.001) in T2DMad. We conclude that parameters indicative of IR, a pathophyiologic component of T2DM, are profoundly altered in patients with T2DMad when compared to T1DMob, and that this does not appear to be linked to differences in age at diabetes presentation.
F. Barbetti: Consultant; Self; Amring. R. Bonfanti: Advisory Panel; Self; Abbott, Medtronic, Roche Diabetes Care. D. Iafusco: None.