Study objectives: Homelessness is a growing problem in the United States that may significantly impair physical health. The homeless have a high prevalence of cigarette smoking, poor nutrition, and adverse environmental exposures, which could contribute to obstructive lung disease (OLD). Despite this risk, the prevalence of OLD among the homeless remains unknown. We aimed to systematically assess the prevalence of OLD among the urban homeless.
Design, setting, and participants: We conducted a cross-sectional study of the prevalence of OLD among homeless individuals in San Francisco. By random sampling, we recruited 68 adults living in one homeless shelter to participate in a structured interview survey and spirometry assessment. We used a multifaceted approach to assess OLD, including respiratory symptoms, self-reported physician diagnosis of asthma, chronic bronchitis, emphysema, or COPD, and spirometry (defined as FEV1 < 80% predicted and FEV1/FVC ratio < 0.70).
Results: Sixty-eight adults completed the survey, and 67 adults completed the spirometry. Homeless adults were likely to be homeless < 1 year and homeless for the first time. There was a high prevalence of cigarette smoking (75% ever smokers, 68% current smokers). The prevalence of symptoms suggestive of OLD was high, including cough (29%), wheezing (40%), chronic bronchitis symptoms (21%), and dyspnea on exertion (29%). A substantial proportion of homeless subjects indicated a prior diagnosis of asthma (24%), chronic bronchitis (19%), and COPD (4%). Based on spirometry, the prevalence of OLD was 15% (95% confidence interval, 8 to 26%), which was more than double the expected prevalence in the general US population.
Conclusions: As OLD is a leading cause of death in the United States, it is important to identify it early for treatment. Homeless individuals have a higher-than-expected prevalence of OLD. Public health interventions should target the homeless population for prevention and treatment of OLD.