Pulmonary Hypertension in COPD Associated With Higher Mortality

Pulmonary hypertension (PH) is common among patients with chronic obstructive pulmonary disease (COPD) and is associated with higher mortality, according to study findings presented at the American Thoracic Society (ATS) 2021 International Conference, held virtually from May 14-19, 2021.

Although PH is a common complication of COPD, little is known about the prevalence and clinical profiles of patients with COPD-PH. Therefore, researchers studied the clinical characteristics, hemodynamic profiles, and prognosis of patients with COPD referred for right heart catheterization (RHC) between 1997 and 2017.

A total of 6065 patients were referred for RHC at Vanderbilt University Medical Center in Nashville, Tennessee, of whom 1509 (24.9%) had COPD and 1213 had COPD-PH (80.4% of those with COPD). Among those with COPD-PH, 12.6% had precapillary PH, 33.6% had postcapillary PH, 21.5% had combined precapillary and postcapillary PH, and 32.3% had PH with wedge pressure <15 mm Hg and pulmonary vascular resistance <3 Wood Units. Patients with COPD-PH had a higher prevalence of diabetes, atrial fibrillation, heart failure, and were more often of Black race compared with COPD without PH. Individuals with COPD-PH had left-sided remodeling (LV hypertrophy and left atrial enlargement) and lower stroke volume and PA oxygen saturation compared with COPD alone (P <.05 for all comparisons).

Pulmonary function testing data from individuals with COPD-PH revealed subtype differences, with precapillary COPD-PH having lower diffusing capacity for carbon monoxide (DLCO) values than other COPD-PH subtypes. Lower forced expiratory volume in 1 second (FEV₁; P ≤.001) and DLCO (P ≤.001) was associated with higher mean pulmonary arterial pressure when adjusted for age, sex, and race. Patients with COPD-PH had significantly increased mortality compared with COPD alone (hazard ratio [HR], 1.70; 95% CI, 1.28-2.26; P =.001), with the highest mortality in the combined precapillary and postcapillary COPD-PH subgroup (HR, 2.39; 95% CI, 1.64-3.47; P =.001).

The researchers concluded, “The etiology of PH in patients with COPD is often mixed due to multimorbidity and is associated with high mortality, which may have implications for risk factor management.”

Reference

Cook DP, Xu M, Annis J, et al. Clinical insights into pulmonary hypertension in chronic obstructive pulmonary disease. Presented at: the American Thoracic Society (ATS) International Conference 2021; May 14-19, 2021. Abstract A4567.