Impact of race-based spirometry equations on guideline-based asthma management in clinical trials

The American Thoracic Society recently recommended that race- and ethnicity-specific equations for spirometry be replaced with race-neutral equations. This change could have implications for asthma management.

Our aim was to examine the effect of race-specific versus race-neutral spirometry reference equations on the resultant guideline-directed asthma therapy in a study population with a high proportion of Black children.

We pooled and harmonized data on 2076 children and adolescents across 4 Inner-City Asthma Consortium studies that had all used a computer-asssisted algorithm for management of asthma medication. The asthma control level was recalculated, first by using the percent predicted FEV₁ values derived from the 2012 race-specific equations and then by using those derived from the Global Lung Initiative GLI Global race-neutral equations. The calculated control level was then used to determine the recommendation for treatment step changes.

Among urban Black children not already at the highest recommended inhaled corticosteroid doses, 18% would have been assigned a higher medication step at study entry when using the race-neutral rather than race-specific reference equations to assess asthma control. A very small number of children in other race or ethnicity groups had a recommendation for a higher medication step.

The transition to use of race-neutral values for measures of lung function has the potential to reduce racial bias in diagnosing and treating asthma.