Subclinical target organ damage in patients with type 1 diabetes mellitus. a prospective preliminary study

Objective: Early atherosclerosis is the main cause of cardiovascular damage and death in patients with type 1 Diabetes Mellitus (T1DM). Some vascular indexes can help to identify and stratify patients before clinical events. This study aims to evaluate the trend over time of some markers of subclinical vascular damage to identify possible associations with anthropometric parameters, blood pressure (BP) and metabolic variables. Design and method: Fifty-six patients with T1DM (mean age: 17.5±2.5 years; mean duration of diabetes: 8.9±4.0 years) were assessed in two occasions (mean follow-up time: 2.7±0.9 years). Peripheral systolic and diastolic BP (pSBP, pDBP), central systolic and diastolic BP (cSBP, cDBP) and Pulse Wave Velocity (PWV) were measured by the SphygmoCorXCEL. Carotid Intima-Media Thickness (cIMT) and the carotid Distensibility Coefficient (cCD) were assessed by ultrasound connected with an image acquisition and analysis system (CardiovascularSuite). Biochemical and anthropometric data were also recorded. Results: At follow-up, PWV and BP values increased significantly while cDC further decreased with the 80.4% of patients that presented a pathological cDC (lower than 40x10 -3 KPa or the 5th percentile). BP values at baseline correlated with all vascular indexes at follow-up: in particular, cSBP was associated with cDC (r = -0.46, p< 0.001), cIMT (r = 0.39, p = 0.004) and PWV (r = 0.32, p = 0.01). These associations remained significant even after adjustment for metabolic (including glycated hemoglobin) and anthropometric parameters. Moreover, baseline arterial stiffness significantly correlated with BP values at follow-up: particularly cDC and PWV were associated with cDBP (r = -0.354, p = 0.009 and r = 0.40, p = 0.002; respectively) even after multiple adjustments. Regarding metabolic parameters, non-HDL-to-HDL-cholesterol ratio correlated with both cDC (r = -0.36, p = 0.007) and PWV (r = 0.30, p = 0.03). Conclusions: The most important finding of this study is the strict and independent association between BP parameters, especially cSBP at baseline, and indexes of vascular damage at follow-up, even after multiple adjustments. Indeed, cDC at baseline is also associated with increased cDBP at follow-up. Our data support the hypothesis of a vicious cycle between BP and arterial stiffness, which may worsen both parameters over time.