Introduction
exacerbations, hypoxia, PH, ECOPD, deaths, Shortness of Breath, COPD
ISCHEMIC HEART DISEASE, CHRONIC OBSTRUCTIVE PULMONARY DISEASE, HYPOXIA, CARDIOVASCULAR MORBIDITY, COPD, RHD, PULMONARY HYPERTENSION
Chronic obstructive pulmonary disease (COPD) afflicts over 65 million people worldwide, resulting in 3 million deaths annually, and in the United States, direct medical costs average over ten thousand dollars annually per patient [Cardiovascular morbidity in COPD patients extends beyond the well-established link with ischemic heart disease. In COPD patients, pulmonary hypertension (PH) related to destruction of lung tissue and chronic hypoxia is relatively common with estimates of PH prevalence using cardiac catheterization ranging from 20 to 36%, and up to 45% with exercise [The Beta-Blockers for the Prevention of Acute Exacerbations of COPD (BLOCK-COPD) trial randomized participants to metropolol vs. placebo for the prevention of ECOPD. Metoprolol did not affect the overall risk of ECOPD, but increased the risk of severe exacerbations requiring hospitalization and worsened respiratory symptoms as assessed by the COPD Assessment Test (CAT) and the San Diego Shortness of Breath Questionairre (SOBQ) [Previous work revealed that P-pulmonale, an ECG indicator of RHD, is both prevalent and associated with increased mortality in PH [We used data from BLOCK-COPD to test the hypothesis that P-pulmonale, an indicator of RHD in PH, is associated with ECOPD and would identify individuals at further risk for increased symptoms and ECOPD when randomized to metoprolol.