The Differential Impact of Emphysema on Respiratory Symptoms and 6-Minute Walk Distance in HIV Infection

• Authors: Matthew Triplette, University of Washington; Engi Attia, University of Washington; Kathleen Akgun, Yale University; Monica Campo, University of Washington; Maria Rodriguez-Barradas, Baylor College of Medicine; Sudhakar Pipavath, University of Washington; Shahida Shahrir, University of Washington; Cherry Wongtrakool, Emory University; Matthew Bidwell Goetz, University of California; Joon Kim, James J. Peters Veterans Affairs Medical Center; Guy W. Soo Hoo, University of California; Sheldon T. Brown, James J. Peters Veterans Affairs Medical Center; Kristina Crothers, University of Washington
• Journal Title: Journal of Acquired Immune Deficiency Syndromes
• Volume: Volume 74, Number 1
• Publisher: Lippincott, Williams & Wilkins | 2017-01-01, Pages E23-E29
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1097/QAI.0000000000001133
• Subjects: Health Sciences, Medicine and Surgery; Health Sciences, Radiology
• Keywords: Science & Technology; Life Sciences & Biomedicine; Immunology; Infectious Diseases; COPD; emphysema; HIV; 6-minute walk distance; OBSTRUCTIVE PULMONARY-DISEASE; ANTIRETROVIRAL THERAPY ERA; IMMUNODEFICIENCY-VIRUS-INFECTION; SPIROMETRY REFERENCE VALUES; VETERANS AGING COHORT; RADIOGRAPHIC EMPHYSEMA; DIFFUSING-CAPACITY; RISK-FACTORS; MORTALITY; ASSOCIATION

Abstract

Background: Emphysema is more prevalent in HIV-infected (HIV+) patients independent of smoking behavior. Nonetheless, health effects of emphysema in this population are poorly understood. We determined whether emphysema is associated with a greater burden of pulmonary symptoms and a lower 6-minute walk distance (6MWD) in HIV+ compared with HIV-uninfected (HIV-) subjects. Methods: We performed a cross-sectional analysis of 170 HIV+ and 153 HIV- subjects in the Examinations of HIV-Associated Lung Emphysema (EXHALE) cohort study. Subjects completed a self-assessment of respiratory symptoms, pulmonary function testing, and 6MWD testing as well as a chest computed tomography to determine emphysema severity. We used regression models to determine the association of emphysema with respiratory symptoms and 6MWD in HIV+ subjects and compared this to HIV- subjects. Results: Models stratified by HIV status demonstrated an association between > 10% radiographic emphysema and chronic cough and/or phlegm and 6MWD in HIV+ subjects. These associations persisted among the subset without airflow obstruction: those with emphysema had 4.2 (95% confidence interval: 1.3 to 14) times the odds of chronic cough and/or phlegm and walked 60 m (95% confidence interval: 26 to 93) less distance than those without emphysema. There was no association between > 10% emphysema and symptoms or 6MWD in HIV- subjects. Conclusions: In our cohort, > 10% radiographic emphysema was associated with chronic cough and/or phlegm and lower 6MWD in HIV+ but not HIV- subjects. These findings were robust even among HIV+ subjects with milder forms of emphysema and those without airflow obstruction, highlighting the clinical impact of emphysema in these patients.