Abstract P054: Duration Of Diabetes, Glucose Excursions, Glycemic Control, And Low Heart Rate Variability: The Atherosclerosis Risk In Communities (aric) Study

Abstract

Introduction: Individuals with diabetes often have low heart rate variability (HRV)—a marker of autonomic dysfunction. How diabetes duration, glucose excursions, and poor glycemic control relate to HRV is not well characterized. Objectives: To evaluate the associations of diabetes status, duration of diabetes, and biomarkers of glucose excursions (1,5-anhydroglucitol [1,5-AG]—a measure of glycosuria) and glycemic control with HRV. Methods: We conducted a cross-sectional analysis of ARIC Study participants who underwent a 2-minute electrocardiogram at visit 4 (1996-98). We considered root mean square of successive differences in normal-to-normal R-R intervals (rMSSD, measure of parasympathetic activity), standard deviation of normal-to-normal R-R intervals (SDNN, total variability), low frequency (LF, primarily sympathetic activity), high frequency (HF, reflects parasympathetic activity), and LF/HF ratio (sympathetic-parasympathetic balance) as HRV indices. In persons with diabetes, we compared geometric means of HRV indices by diabetes duration (<5 years vs ≥5 years), 1,5-AG (<6 μg/mL vs ≥6 μg/mL), and glucose control (estimated A1C <8% vs ≥8%). We obtained p-values from linear regressions adjusted for age and sex. Results: Among 10169 participants (mean age 63, 57% female, 22% black), participants with diabetes had significantly lower rMSSD, SDNN, LF, HF, and LF/HF ratio compared to those without diabetes ( Table ). Among the 1667 participants with diabetes, longer duration of diabetes, low 1,5-AG, and poor glycemic control were associated with lower rMSSD, SDNN, LF, and HF. No statistically significant associations were found for diabetes duration, 1,5-AG, glycemic control with LF/HF ratio. Discussion: Our results demonstrate that longer duration of diabetes, glucose excursions, and poor glycemic control are associated with some measures of low HRV. This study underscores that cardiac autonomic neuropathy is a common but overlooked complication of long-standing and/or poorly managed diabetes.