Sleep-disordered Breathing and Markers of Morbidity in Children and Adolescents with Cystic Fibrosis

Background: Studies have shown that sleep disorders occur in cystic fibrosis (CF) patients and may be present before daytime clinical manifestations.

Objectives: To evaluate the presence of sleep disorders among children and adolescents with CF, attempting to identify associations with pulmonary function, nutritional status, days in hospital, and days taking antibiotics.

Methods: Individuals with a diagnosis of CF aged between 6 and 18 years were included. Information on sociodemographic, clinical profile, history of hospitalizations, and use of antibiotics in the last year were collected. Spirometry, bioimpedance, and polysomnography were performed. The presence of nocturnal hypoxemia and obstructive sleep apnea syndrome (OSAS) were evaluated and participants divided according to their presence.

Results: Thirty-one patients were included. The prevalence of OSAS was 32.3% and nocturnal hypoxemia was 29.0%. Average nocturnal peripheral oxyhemoglobin saturation (SpO ) correlated (P < .001) with forced vital capacity (r = .55) and forced expiratory volume in the first second (r = .62). The higher the percentage of total sleep time (TST) with SpO less than 90%, the lower the pulmonary function. Individuals with OSAS and nocturnal hypoxemia had lower spirometric values compared to patients without these disorders, but the nocturnal hypoxemia group also had lower Shwachman-Kulczycki score, longer hospitalization time and antibiotic use. TST with SpO less than 90% was associated with length of hospitalization (r  = .53).

Conclusion: Children and adolescents with CF have sleep disorders, including OSAS (32.3%) and nocturnal hypoxemia (29%). Individuals with nocturnal hypoxemia presented lower lung function, worse clinical score, and higher morbidity. TST with SpO less than 90% was associated with length of hospitalization.