Coronary artery disease is under-diagnosed and under-treated in advanced lung disease

Abstract

Background: Coronary artery disease is a potentially treatable comorbidity observed frequently in both chronic obstructive pulmonary disease and interstitial lung disease. The prevalence of angiographically proven coronary artery disease in advanced lung disease is not well described. We sought to characterize the treatment patterns of coronary artery disease complicating advanced lung disease and to describe the frequency of occult coronary artery disease in this population.

Methods: We performed a 2-center, retrospective cross-sectional study of patients with either chronic obstructive pulmonary disease or interstitial lung disease evaluated for lung transplantation. Medications and diagnoses before the transplant evaluation were recorded in conjunction with left heart catheterization results.

Results: Of 473 subjects, 351 had chronic obstructive pulmonary disease, and 122 had interstitial lung disease. In subjects diagnosed clinically with coronary artery disease, medical regimens included a statin in 78%, antiplatelet therapy in 62%, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker in 42%, and a beta-blocker in 37%. Ten percent were on no medication from these 4 classes. Fifty-seven percent of these subjects were on an antiplatelet agent as well as a statin, and 13% were on neither. Beta-blockers were less frequently prescribed in chronic obstructive pulmonary disease than interstitial lung disease (23% vs 58%, P=.007). Coronary angiography was available in 322 subjects. It demonstrated coronary artery disease in 60% of subjects, and severe coronary artery disease in 16%. Occult coronary artery disease and severe occult coronary artery disease were found in 53% and 9%, respectively. There were no significant differences in angiographic results between chronic obstructive pulmonary disease and interstitial lung disease, despite imbalanced risk factors.

Conclusions: Coronary artery disease is common in patients with advanced lung disease attributable to chronic obstructive pulmonary disease or interstitial lung disease and is under-diagnosed. Guideline-recommended cardioprotective medications are suboptimally utilized in this population.