Longitudinal Changes in Arterial Stiffness and Heart Rate Variability In Youth-Onset Type 1 vs Type 2 Diabetes: The SEARCH for Diabetes in Youth Study
Research Design and Methods: Arterial stiffness (pulse wave velocity, augmentation index) and six indices of heart rate variability were measured twice, 4.5 years apart among participants with either youth-onset type 1 or type 2 diabetes in the SEARCH for Diabetes in Youth Study. Multivariable linear regression models assessed risk factors associated with arterial stiffness and HRV at follow-up assessment.
Results. Of 1159 participants studied, 949 had type 1 (mean age 17.1 ± 4.7 years, 60.3% non-Hispanic White, 55% female) and 210 had type 2 diabetes (mean age 22.1 ± 3.5 years, 23.8% non-Hispanic White, 71% female) at initial assessment when diabetes duration was 7.9 years (both groups). Participants with type 2 vs type 1 diabetes had greater vascular stiffness and more abnormalities in HRV at initial and follow-up assessment and a greater change over time (all p<0.05). Risk factors associated with worse arterial stiffness and HRV at follow-up in both types of diabetes included higher blood pressure, hemoglobin A1c, waist circumference, and triglycerides, and longer diabetes duration.
Conclusions. Arterial stiffness and HRV worsened over time with greater changes among those with type 2 compared with type 1 diabetes, and among those with features of the metabolic syndrome. The risk factor profile documents potentially modifiable pathways to prevent or limit cardiovascular complications in young adults with youth-onset diabetes.