Cardiovascular Autonomic Function and Incident COPD Hospitalizations in ARIC.

Abstract

The autonomic nervous system extensively innervates the lungs but its role in COPD outcomes has not been well-studied. We assessed relationships between cardiovascular autonomic nervous system measures (heart rate variability [HRV] and orthostatic hypotension [OH]) and incident COPD hospitalization in the Atherosclerosis Risk in Communities (ARIC) study. Cox proportional hazards regression models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) between baseline (1987-1989) autonomic function measures (HRV measures from 2-minute electrocardiograms and OH variables) and incident COPD hospitalizations through 2019. Models included demographics, smoking status, lung function, co-morbidities, and physical activity. We also performed analyses stratified by baseline airflow obstruction. Of the11,625 participants (mean age 53.8 years, 56.5% female), 26.3% identified as Black. Baseline mean (±SD) percent predicted FEV1 was 94 ± 17% and 2,599 (22.4%) had airflow obstruction. Over a median follow-up time of 29 years, there were 2,406 incident COPD hospitalizations. Higher HRV (i.e. better autonomic function) was associated with lower risk of incident COPD hospitalization. Markers of worse autonomic function (OH and greater orthostatic changes in systolic and diastolic blood pressure) were associated with higher risk of incident COPD hospitalization [HR (95% CI) for presence of OH 1.51 (1.25 to 1.92)]. In stratified analyses, results were more robust in participants without baseline airflow obstruction. In this large, multicenter, prospective community cohort, better cardiovascular autonomic function at baseline was associated with lower risk of subsequent hospitalization for COPD, particularly among participants without evidence of lung disease at baseline.