PURPOSE OF THE STUDY.
In 2012, as a result of the Global Lung Function Initiative, the first global, all-age (3–95 years of age), multiethnic reference equations for spirometry (GLI-2012) were published. The authors of the present paper, as part of the Size and Lung Function in Children study, sought to investigate existing ethnic differences in lung function in a multiethnic population of children and to validate the GLI-2012 reference equations in this population.
Technically acceptable spirometric data were obtained from 1088 healthy children. The children were classified into 4 main ethnic groups: white, black, South Asian, and other/mixed.
Spirometric data were expressed as percent predicted on the basis of the GLI-2012 equations for white subjects, adjusted for age, gender, and height and then on the basis of the ethnic-specific GLI-2012 equations.
When compared with white children, forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) were significantly lower by a mean of ∼12% in black and Asian children and by 5% in other/mixed race children. FEV1 and FVC were reduced proportionally such that the FEV1/FVC ratio was unaffected. When data were expressed according to the GLI-2012 ethnic-specific reference equations, the mean FEV1 and FVC z scores approximated 0, indicating that the GLI-2012 equations appropriately compensate for these ethnic differences.
The authors concluded that although there are significant ethnic differences in FEV1 and FVC in primary school-children, the magnitude of which is similar to that reported in older subjects, these differences can be minimized by using the GLI-2012 ethnic-specific reference equations.
Just as in adults, there are marked ethnic differences in lung function in children, even after correcting for age, height, and gender, particularly for children of African or Asian descent. To generate accurate spirometric results, ethnic-specific reference equations should be used where available or corrections should be made to reference equations derived from white subjects by using appropriate percent reductions.
- Copyright © 2014 by the American Academy of Pediatrics