Association of Cardiovascular Autonomic Dysfunction With Peripheral Arterial Stiffness in Patients With Type 1 Diabetes

CONTEXT: Cardiovascular autonomic neuropathy (CAN) appears to contribute to peripheral arterial stiffness (AS) in type 1 diabetes. Whether CAN in patients with AS is associated with concomitant asymptomatic peripheral arterial disease (aPAD) remains unclear. OBJECTIVE: To assess the risk of CAN in patients with type 1 diabetes and AS and its potential association with atherosclerosis. DESIGN: Cross-sectional study. SETTING: Type 1 diabetes clinic in an academic hospital. PATIENTS: Two hundred sixty-four patients with type 1 diabetes. INTERVENTION: AS was defined as an ankle-brachial index (ABI) >1.2, aPAD by the toe-brachial index and Doppler sonography, and CAN by blood pressure and heart rate responses to active standing and Ewing and Clarke tests. MAIN OUTCOME MEASURES: Odds of having CAN among patients with AS. Odds for CAN were also calculated as a function of the presence of AS and concomitant aPAD. RESULTS: The study population's mean age was 35 ± 11 years, with a duration of disease of 19 ± 10 years and mean hemoglobin A1c of 7.5% ± 1.3%. Seventy-three patients (28%) had peripheral AS, of whom 28 showed aPAD. The prevalence of CAN among patients with AS was 48% but it was only 23% in subjects with normal ABI (OR: 3.1 [1.7; 5.4]). Concomitant aPAD increased the OR for CAN (OR: 4.5 [2.0; 10.1]). After adjustments for aPAD and relevant cardiovascular risk factors, AS remained associated with parasympathetic dysfunction. CONCLUSIONS: In type 1 diabetes, both peripheral AS and atherosclerosis were associated with CAN. A simple method, such as the ABI, may identify a subset of patients with undiagnosed dysautonomia.