Screening for chronic obstructive pulmonary disease (COPD) in an urban HIV clinic
Methods: A convenience sample of subjects at least 35 years of age at an HIV primary care clinic in New York City were enrolled and completed a COPD screening questionnaire and peak flow measurement. Those with abnormal results and a randomly selected 1/3 of normal screens went on to have spirometry testing.
Results: In total, 235 individuals were included in the study and 94 qualified for spirometry (89 produced interpretable results). The majority of patients were male, men who have sex with men, low income earners, had a smoking history and carried an AIDS diagnosis. Eleven subjects (12%) were found to have undiagnosed obstructive lung disease and 5 of these had COPD by GOLD criteria. The combination of positive screening questionnaire and abnormal peak flow yielded a sensitivity of 20% and specificity of 93% for COPD. Peak flow alone had a sensitivity of 80% and a specificity of 80%. Abnormal peak flow (<70% of predicted) was associated with an AIDS diagnosis (p=0.04), lower nadir (p=0.001) and current CD4 counts (p=0.001), but only nadir CD4 remained associated in multivariate analysis (p=0.05). In multivariate analysis, decreased FEV1 (<80% predicted) was associated with lower CD4 count nadir (p=0.04) and having a detectable current HIV viral load (p=0.01). Decreased FVC was associated with having a detectable current viral load (p=0.01).
Conclusion: In summary, the combination of a screening questionnaire and peak flow had low sensitivity, but abnormal peak flow alone showed potential as a simple office-based screening tool for the diagnosis of COPD in PLWHA. In addition, measures of lung function, including peak flow, may be influenced by HIV-related factors.
M. Glesby, None