Peripheral artery tonometry demonstrates altered endothelial function in children with type 1 diabetes

Objectives: To assess the ability of reactive hyperemia-peripheral artery tonometry (RH-PAT) to serve as a surrogate marker of endothelial dysfunction in children with type I diabetes (TID). Research Design and Methods: Forty-four children with TID [age 14.6 +/- 2.7 yr; duration of diabetes 6.01 +/- 4 yr; range of diabetes duration 1-16 yr; and hemoglobin Alc (HbAlc) 8.34 +/- 1.2%] and 20 children without diabetes (age 14.1 +/- 1.5 yr) underwent RH-PAT endothelial. function testing after an overnight fast. Height, weight, body mass index; (BMI), blood pressure (BP), fasting lipid profile, and glucose level were determined in each child. Children with TID underwent a second RH-PAT study 4 wk after their initial study to determine the intrapatient variability of the technique. Results: Children with TID had endothelial dysfunction as evidenced by lower mean RH-PAT scores (1.63 +/- 0.5) when compared with children without diabetes (mean RH-PAT score 1.95 +/- 0.3) (p = 0.01). Repeat RH-PAT scores were predicted by initial RH-PAT scores (p = 0.0025). Mean intrapatient standard deviation of RH-PAT score was 0.261 and mean coefficient of variation was 14.8. Variations in RH-PAT score were not explained by differences in glucose, HbAlc, BMI, systolic BP, diastolic BP, or lipids. Conclusions: Although larger validation studies are required, RH-PAT is a promising non-invasive technique to assess endothelial function in children with TID. Non-invasive measures of endothelial dysfunction may provide the additional risk stratification data needed to justify more aggressive primary prevention of cardiovascular disease in children with TID.