The implications of removing race from interpretation of pulmonary function among persons with or without HIV

Background: Studies suggest that the use of race-specific pulmonary function reference equations may obscure racial inequities in respiratory health. Whether removing race from the interpretation of pulmonary function would influence analyses of HIV and pulmonary function is unknown.

Setting: Pulmonary function measurements from 1,067 men (591 with HIV) in the Multicenter AIDS Cohort Study (MACS) and 1,661 women (1,175 with HIV) in the Women's Interagency HIV Study (WIHS) were analyzed.

Methods: Percent-of-predicted values for spirometry and single-breath diffusing capacity of carbon monoxide (DLCO) measurements were generated with race-specific reference equations derived from the National Health and Nutrition Examination Survey and with the race-neutral application of reference equations derived from the Global Lung Function Initiative database. Regression models were used to evaluate the association between HIV and percent-of-predicted measures of pulmonary function. Alpaydin's F test was used to compare how well these values predicted self-reported respiratory health-related quality of life.

Results: Persons with HIV were observed to have significantly lower percent-of-predicted DLCO than those without HIV but no significant differences in spirometric measures of pulmonary function, regardless of whether a race-specific or race-neutral approach was used. Among men, but not women, the race-neutral application of reference equations to generate percent-of-predicted DLCO values performed better for predicting respiratory-related quality of life.

Conclusion: The race-neutral application of pulmonary function reference equations continues to identify lung function impairment in persons with or at risk for HIV and, for DLCO, may be superior to the use of race-specific reference equations in identifying clinically relevant impairments.