Reduced lung function in healthy preterm infants in the first months of life.
BACKGROUND
Preterm delivery has been associated with a higher incidence of respiratory morbidity even in infants that do not have significant respiratory disease during the neonatal period. Reduced flows have been reported in children and adolescents born prematurely.


OBJECTIVE
The aim of this study was to assess lung function in healthy preterm infants in the first months of life.


METHODS
Preterm infants with less than 48 h of supplemental oxygen were recruited. Lung function was assessed by the raised-volume rapid thoracic compression in the first months of life. The control group consisted of full-term infants without a history of respiratory diseases.


RESULTS
Sixty-two preterm (29 male) and 27 full-term (10 male) infants were tested. Adjusting for length, age, and sex, we found a mean significant reduction of 92 ml/s (22%) in FEF(50), 73 ml/s (21%) in FEF(25-75), and 19 ml (28%) in FEV(0.5) in the preterm group. These differences in expiratory flows remained significant using another model that adjusts for lung volume (p < 0.01 for FEF(50), FEF(25-75), and FEV(0.5), and p < 0.05 for FEF(75)). In the preterm group, after adjusting for length, male sex, lower gestational age, and increased weight were significantly and independently associated with reduced flows.


CONCLUSIONS
Our findings confirm that prematurity is independently associated with reduced lung function and that this is detectable in the first months of life. Male sex, lower gestational age, and weight are important predictors for reduced expiratory flows in this group.
Friedrich
Luciana
L
Department of Pediatrics, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil.
Stein
Renato T
RT
Pitrez
Paulo M C
PM
Corso
Andrea L
AL
Jones
Marcus H
MH
D002675:Child, Preschool; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008450:Maximal Midexpiratory Flow Rate