Background: few data are available on cardiovascular (CV) involvement in young DM1 subjects with disease onset in pediatric age.

Aim: to assess preclinical CV changes in young patients with early onset DM1.

Methods: Thirty DM1 normotensive subjects (age =19.4±3.2 years, BMI=22.1±2.7 kg/m², disease duration=10.7±5.4 years, HbA1c=7.8±1.4%) without macro- and microvascular complications, and 14 controls (C) of comparable age and BMI. Common carotid artery (CCA) IMT, local stiffness (ß and Ep) and wave speed (WS) were obtained by echo-tracking (Aloka Alpha10). Aortic stiffness was assessed by carotid-femoral pulse wave velocity (PWV). Myocardial tissue velocities, LV geometry and function were evaluated by echocardiography.

Results: DM1 had, compared to C, higher (p<0.05) diastolic BP (DBP: 68±7 vs 62±4 mmHg), interventricular septum thickness (IVS) (0.76±0.11 vs 0.65±0.10 cm) and LV relative wall thickness (RWT: 0.31±0.4 vs 0.28±0.03). No differences between groups were found for pulse pressure, LV mass index, midwall shortening, transmitral E/A, myocardial velocities, CCA IMT and stiffness, WS and PWV. In the entire population, DBP increased with age, BMI, WS and PWV (r from 0.33 to 0.38, p < 0.05), and IVS increased with SBP and BMI (r=0.35 and 0.49, p<0.05). Independent predictors of DBP were WS and DM1 (R2=0.23, p<0.005), whereas predictors of IVS were sex, BMI and DM1 (R2=0.53, p<0.0001). RWT was independently related to DM1 (R²=0.12, p<0.05).

Conclusions: well controlled young DM1 subjects show mildly elevated DBP and a trend towards LV concentric remodelling. Whether arterial stiffness is mechanism or result of increased DBP remains to be established.