Reduced Heart Rate Variability Is AssociatedWith Increased Arterial Stiffness in YouthWith Type 1 Diabetes The SEARCH CVD study

OBJECTIVEdReduced heart rate variability (HRV) and increased arterial stiffness (AS) are both present in youthwith type 1 diabetes. However, it is unclear whether they are associated and whether their association is independent of cardiovascular disease (CVD) risk factors. RESEARCH DESIGN AND METHODSdThe SEARCH Cardiovascular Disease (SEARCH CVD) study explored the cross-sectional relationships between HRV and several measures of AS in youth with (n = 344) and without (n = 171) type 1 diabetes. The SphygmoCor device (AtCor Medical, Sydney, Australia) was used to measure HRV using SD of normal R-R interval (SDNN), as well as AS, using pulse wave velocity in the carotid to femoral segment (PWV-trunk) and augmentation index adjusted to a heart rate of 75 bpm (AIx75). Brachial distensibility (BrachD), another index of AS, was measured with a DynaPulse instrument (Pulse Metric, San Diego, CA). Multiple linear regression analyses explored the associations between HRV and each of the three ASmeasures, after adjusting for demographic characteristics and traditional CVD risk factors (blood pressure, lipids, obesity, microalbuminuria, and smoking) separately, for youth with and without type 1 diabetes. RESULTSdAmong youth with type 1 diabetes, lower SDNN was associated with periphera