HIV infection is associated with reduced pulmonary diffusing capacity

Author(s): Crothers, Kristina; McGinnis, Kathleen; Kleerup, Eric; Wongtrakool, Cherry; Hoo, Guy S; Kim, Joon; Sharafkhaneh, Amir; Huang, Laurence; Luo, Zhaoyu; Thompson, Bruce; Diaz, Philip; Kirk, Gregory D; Rom, William; Detels, Roger; Kingsley, Lawrence; Morris, Alison | Abstract: IntroductionPrior studies comparing abnormalities in pulmonary function between HIV-infected and HIV-uninfected persons in the current era are limited.ObjectivesTo determine the pattern and severity of impairment in pulmonary function in HIV-infected compared with HIV-uninfected individuals.MethodsCross-sectional analysis of 300 HIV-infected men and 289 HIV-uninfected men enrolled from 2009 to 2011 in 2 clinical centers of the Lung HIV Study. Participants completed pre- and postbronchodilator spirometry, diffusing capacity of the lung for carbon monoxide (DLCO) measurement, and standardized questionnaires.ResultsMost participants had normal airflow; 18% of HIV-infected and 16% of HIV-uninfected men had airflow obstruction. The mean percent predicted DLCO was 69% in HIV-infected vs. 76% in HIV-uninfected men (P l 0.001). A moderately to severely reduced DLCO of ≤60% was observed in 30% of HIV-infected compared with 18% of HIV-uninfected men (P l 0.001), despite the fact that 89% of those with HIV were on antiretroviral therapy. A reduced DLCO was significantly associated with HIV and CD4 cell count in linear regression adjusting for smoking and other confounders. The DLCO was lowest in HIV-infected men with CD4 cell counts l200 cells per microliter compared with those with CD4 cell counts ≥200 cells per microliter and to HIV-uninfected men. Respiratory symptoms of cough, phlegm and dyspnea were more prevalent in HIV-infected patients particularly those with abnormal pulmonary function compared with HIV-uninfected patients.ConclusionsHIV infection is an independent risk factor for reduced DLCO, particularly in individuals with a CD4 cell count below 200 cells per microliter. Abnormalities in pulmonary function among HIV-infected patients manifest clinically with increased respiratory symptoms. Mechanisms accounting for the reduced DLCO require further evaluation.