Markers of cardiovascular autonomic dysfunction predict COPD in middle-aged subjects

Autonomic dysfunction is commonly observed in chronic obstructive pulmonary disease (COPD) and may relate to the known comorbidity with coronary artery disease (CAD). We hypothesised that clinical markers of cardiovascular autonomic dysfunction predict COPD in the population, independently of CAD.In a population-based cohort of 24 768 subjects (mean age 45 years) without baseline airflow obstruction, we analysed the cross-sectional relationship of one-minute orthostatic systolic blood pressure (SBP) and diastolic blood pressure (DBP) changes and resting heart rate with forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV₁). Cox regression models were used to analyse the association of orthostatic SBP and DBP changes (SBP/DBP decrease) and resting heart rate with incident COPD over a 32-year follow-up.Baseline orthostatic SBP decrease (p=0.020) and DBP decrease (p=0.001) were associated with reduced FVC, whereas resting heart rate was associated with reduced FVC and FEV₁ (p<0.001). After adjustment for smoking and baseline lung function, SBP decrease predicted COPD (hazard ratio (HR) 1.10 per 10 mmHg, 95% CI 1.03-1.18). Resting heart rate predicted COPD among smokers (HR 1.11 per 10 beats-per-minute increase, 95% CI 1.05-1.18). Results were similar in subjects without CAD.Subtle signs of cardiovascular autonomic dysfunction may precede the development of COPD in middle-aged subjects. This association is independent of the relationship between cardiovascular autonomic dysfunction and CAD.