Key chronic lung diseases
Ken M. Kunisaki, MD, MS, associate professor of medicine at the University of Minnesota, Minneapolis, and the first author of the MACS analysis of lung function – one of the most recent and largest reports of DLCO impairment – points out that studies of chest computed tomography (CT) have also documented higher rates of emphysema and interstitial lung abnormalities.
Dr. Ken M. Kunisaki
A chest CT analysis from a cohort in Denmark (the Copenhagen Comorbidity in HIV Infection [COCOMO] cohort) found interstitial lung abnormalities in 10.9% of more than 700 PWH which represented a 1.8-fold increased risk compared to HIV-negative controls. And a study from an Italian sample of never-smoking PWH and controls reported emphysema in 18% and 4%, respectively. These studies, which did not measure DLCO, are among those discussed in a 2021 review by Dr. Kunisaki of advances in HIV-associated chronic lung disease research.
Dr. Alison Morris
COPD is the best studied and most commonly encountered chronic lung disease in PWH. “Particularly for COPD, what’s both interesting and unfortunate is that we haven’t really seen any changes in the epidemiology with ART (antiretroviral therapy) – we’re still seeing the same findings, like the association of HIV with worse COPD at younger ages,” said Alison Morris, MD, MS, professor of medicine, immunology, and clinical and translational research at the University of Pittsburgh. “It doesn’t seem to have improved.”
Its prevalence has varied widely from cohort to cohort, from as low as 3% (similar to the general population) to over 40%, Dr. Kunisaki said, emphasizing that many studies, including studies showing higher rates, have controlled for current and past smoking. In evaluating patients with low or no smoking burden, “don’t discount respiratory symptoms as possibly reflecting underlying lung disease because COPD can develop with low to no smoking history in those with HIV,” he advised.
A better understanding of how a chronic viral infection like HIV leads to heightened COPD risk will not only help those with HIV, he notes, but also people without HIV who have COPD but have never smoked – a woefully underappreciated and understudied population. Ongoing research, he said, “should help us understand COPD pathogenesis generally.”
Research on asthma is relatively limited thus far, but it does appear that PWH may be more prone to developing severe asthma, just as with COPD, said Dr. Kunisaki, also a staff physician at the Minneapolis Veterans Administration Health Care System. Research has shown, for instance, that people with HIV more frequently needed aggressive respiratory support when hospitalized for asthma exacerbations.
It’s unclear how much of this potentially increased severity is attributable to the biology of HIV’s impact on the body and how much relates to social factors like disparities in income and access to care, Dr. Kunisaki said, noting that the same questions apply to the more frequent COPD exacerbations documented in PWH.
Dr. Crothers points out that, while most studies do not suggest a difference in the incidence of asthma in PWH, “there is some data from researchers looking at asthma profiles [suggesting] that the biomarkers associated with asthma may be different in people with and without HIV,” signaling potentially different molecular or biologic underpinnings of the disease.
Incidence rates of lung cancer in PWH, meanwhile, have declined over the last 2 decades, but lung cancer remains the leading cause of cancer-related mortality in PWH and occurs at a rate that is 2-2.5 times higher than that of individuals not infected with HIV, according to
Dr. Janice Leung
Janice Leung, MD, of the division of respiratory medicine at the University of British Columbia and the Centre for Heart Lung Innovation at St. Paul’s Hospital in Vancouver.
Patients with HIV have “worse outcomes overall and a higher risk of mortality, even when presenting at the same stage,” said Dr. Leung, who reviewed trends in COPD and lung cancer in a recently published opinion piece.