Spirometry in 3-to 6-year-old children with cystic fibrosis

Spirometry is routinely used to assess pulmonary function of older children and adults with cystic fibrosis (CF); however, few data exist concerning the preschool age group. We have reported normative spirometric data for 3- to 6-year-old children. The current study was designed to assess a similarly aged group of clinically stable patients with CF. Thirty-three of 38 children with CF were able to perform 2 or 3 technically acceptable maneuvers. These patients had significantly decreased FVC, FEV1, FEV1/FVC, and FEF25-75 when expressed as z scores (number of SD from predicted): -0.75 +/- 1.63, -1.23 +/- 1.97, -0.87 +/- 1.33, and -0.74 +/- 1.63, respectively. There were significant positive correlations of the Brasfield radiological score with FVC and FEV1 z scores (r(2) = 0.26, p < 0.01 and r(2) = 0.24, p < 0.01). In addition, homozygous patients for the DeltaF508 mutation had lower z scores for FVC (-1.21 versus 0.47, p < 0.01) and FEV1 (-1.38 versus 0.21, p < 0.05) than heterozygous patients. Of the 14 patients who had full flow-volume spirometric measurements during infancy, 10 had FEF25-75 z scores greater than -2 at both evaluations. Our findings suggest that spirometry can successfully be used to assess lung function in preschool children with CF and has the potential for longitudinal assessment from infancy through adulthood.