Polysomnographic Markers in Children With Cystic Fibrosis Lung Disease.
OBJECTIVE
Children with cystic fibrosis (CF) often report poor sleep, increased daytime sleepiness, and fatigue. The purpose of this study was to identify respiratory patterns over the spectrum of disease severity in children with CF. The overall hypothesis for the current study is that children with CF compared with snoring control subjects demonstrate gas exchange abnormalities and increased respiratory loads during sleep that are not reported or recognized by conventional polysomnography (PSG).


METHODS
Analysis of breathing patterns and gas exchange on PSG was performed in children with CF and healthy controls matched by age and BMI. For all CF and control subjects, the indication for PSG was evaluation for obstructive sleep apnea based on a history of snoring.


RESULTS
Children with CF, compared with age- and BMI-matched snoring controls, demonstrated lower oxyhemoglobin saturation (95% ± 1.6% vs 98% ± 0.6%, P = .005), higher respiratory rate (19.5 ± 4.9 vs 16.5 ± 1.2 breaths per minute, P = .03), and a higher proportion of inspiratory flow limitation (44.1% ± 24.7% vs 12.1% ± 13.5%, P = .007) during non-rapid eye movement sleep. The respiratory disturbance index did not differ between CF and snoring control groups (1.5 ± 2.7 vs 0.6 ± 0.6 events per hour, P = .11).


CONCLUSIONS
Children with CF exhibited abnormalities in gas exchange and increased respiratory load during sleep compared with normal age- and BMI-matched snoring controls. Because these abnormalities were independent of weight and lung function, sleep state may serve as an opportunity for early detection of breathing abnormalities and possibly CF lung disease progression.
Eudowood Division of Pediatric Respiratory Sciences, and sparanj1@jhmi.edu.
Shruti M
SM
Paranjape
Division of Pediatric Pulmonary, Sleep Medicine, and Cystic Fibrosis, University of Utah, Salt Lake City, Utah.
Brian M
BM
McGinley
Sleep Disorders Center, Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland; and.
Andrew T
AT
Braun
Sleep Disorders Center, Division of Pulmonary and Critical Care Medicine, Johns Hopkins University, Baltimore, Maryland; and.
Hartmut
H
Schneider
D002648:Child; D003550:Cystic Fibrosis / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D017286:Polysomnography; D011659:Pulmonary Gas Exchange; D012119:Respiration; D012189:Retrospective Studies