Idiopathic pulmonary fibrosis is more strongly associated with coronary artery disease than chronic obstructive pulmonary disease.

INTRODUCTION: Previous studies have shown that the population attributable risk of low forced expiratory volume in one second (FEV1) for coronary artery disease (CAD) is substantial. FEV1 can be low either because of airflow obstruction or ventilatory restriction. It is not known if low FEV1 arising from spirometric obstruction or restriction are differently associated with CAD. METHODS: We analyzed high resolution computed tomography (CT) scans acquired at full inspiration in lifetime non-smoker adults with no lung disease (controls) and those with chronic obstructive pulmonary disease enrolled in the Genetic Epidemiology of COPD (COPDGene) study. We also analyzed CT scans of adults with idiopathic pulmonary fibrosis (IPF) from a cohort of patients attending a quaternary referral clinic. Participants with IPF were matched 1:1 by FEV1 %predicted to adults with COPD and 1:1 by age to lifetime non-smokers. Coronary artery calcium (CAC), a surrogate for CAD, was measured by visual quantification on CT using the Weston score. Significant CAC was defined as Weston score ≥7. Multivariable regression models were used to test the association of the presence of COPD or IPF with CAC, with adjustment for age, sex, body-mass-index, smoking status, hypertension, diabetes mellitus, and hyperlipidemia. RESULTS: We included 732 subjects in the study; 244 with IPF, 244 with COPD, and 244 lifetime non-smokers. The mean (SD) age was 72.6 (8.1), 62.6 (7.4), and 67.3 (6.6) years, and median (IQR) CAC was 6 (6), 2 (6), and 1 (4), in IPF, COPD, and non-smokers, respectively. On multivariable analyses, the presence of COPD was associated with higher CAC compared to non-smokers (adjusted regression coefficient, ß = 1.10 ± SE0.51; P = 0.031). The presence of IPF was also associated with higher CAC compared to non-smokers (ß = 03.43 ± SE0.41; P < 0.001). The adjusted odds ratio for having significant CAC was 1.3, 95% CI 0.6 to 2.8; P = 0.53 in COPD and 5.6, 95% CI 2.9 to 10.9; P < 0.001 in IPF, compared to non-smokers. In sex stratified analyses, these associations were mainly noted in women. CONCLUSION: Adults with IPF displayed higher coronary artery calcium than those with COPD after accounting for age and lung function impairment.

Access to Pulmonary Rehabilitation among Medicare Beneficiaries with Chronic Obstructive Pulmonary Disease.

Rationale: Pulmonary rehabilitation (PR) remains substantially underused as a treatment modality for chronic obstructive pulmonary disease (COPD). A major barrier to the uptake of PR is the poor availability of and access to PR. Objectives: To quantify patients' access to PR centers in the United States. Methods: Using the 100% Medicare population with coverage for 2018, four geodesic distance-based buffers of 10-, 15-, 25-, and 50-mi radii around the geographic centroid of each ZIP code with at least one beneficiary with COPD were created. Street addresses of PR centers across the continental United States were geocoded. We calculated the distance between the residential ZIP code centroid and the closest PR center. The proportions of individuals with at least one PR center available within the four distance buffers were calculated overall as well as in metropolitan, micropolitan, small-town, and rural areas. Results: Of 62,930,784 Medicare beneficiaries, 10,376,949 (16.5%) had COPD. There were 1,696 PR centers across the United States, with one PR center for every 6,030 individuals with COPD. Mean distance to the nearest PR center was 12.4 (standard deviation, 16.6) mi. Overall, the proportions of individuals with COPD who had PR centers available within 10-, 15-, 25-, and 50-mi radii were 61.5%, 73.2%, 86.6%, and 97.1%, respectively. Proportions for rural areas were 11.3%, 24.3%, 53.4%, and 88.6%, respectively. Compared with those living in metropolitan areas, those living in rural areas were 95% less likely to have PR centers within 10 mi of their residences (odds ratio, 0.048 [95% confidence interval, 0.039-0.057]). Conclusions: In a nationally representative sample of Medicare beneficiaries, we found that two-fifths of adults with COPD overall, and eight in nine of those in rural areas, have poor access to PR.