Abstract
Incidence of sleep-disordered breathing (SDB) increases in chronic lung diseases. Our aim was to evaluate SDB and sleep quality in children with postinfectious bronchiolitis obliterans (BO) and assess associated risk factors. We hypothesized that children with BO are at increased risk for SDB, have impaired sleep quality which is related to the severity of lung disease. Pediatric Sleep Questionnaire (PSQ) and Pittsburgh Sleep Quality Index questionnaires; spirometry, impulse oscillometry (IOS) and overnight polysomnography (PSG) were performed. Twenty-one patients (14 male, median age: 8.3 years) were enrolled. Five patients (25%) had a PSQ score of >0.33. Ten patients (48%) had poor sleep quality. Four patients (19%) had an OAHI of >1/hr. Nineteen patients (90%) had high desaturation index. Four patients (19%) had mean oxygen saturation of <93%. Median central apnea time was 7.5 (IQR: 6.9-9.1) seconds. Central apnea index of the patients correlated positively with R5, R10, R15, R20, Z5 and negatively with X10 and X15 at IOS. There was a positive correlation between the lowest oxygen saturation and FVC, FEV₁, X5, X10, X15, X20 while there was a negative correlation between lowest saturation and central apnea index at PSG, R5, R10 and Z5 at IOS. Mean oxygen saturation during PSG correlated positively with FVC, FEV₁, FEF25-75, X5, X10, X15, X20 results. The risk of nocturnal hypoxia is increased in patients with BO and corelated to the severity of lung disease determined by pulmonary function tests. Although BO patients have shorter duration of central apneas, they are more prone to desaturate.