Severity of obstructive sleep apnea in children with sickle cell disease

Objective: To characterize polysomnographic (PSG) findings of children with sickle cell disease (SCD) suspected of having sleep disordered breathing (SDB). Methods: Families of 100 consecutively referred children with SCD completed the Children's Sleep Habit Questionnaire during a routine visit to identify concerns regarding sleep habits and sleep behavior. Of these, 48 children were identified as displaying behaviors suspicious of SDB. Nineteen agreed to an overnight PSG. The results from the PSGs of the SCD with obstructive sleep apnea syndrome (OSAS) group (SCD-OSAS; group 1) were compared with the results of 10 age, sex, and ethnicity-matched patients identified as OSAS with no medical comorbidities (uncomplicated OSAS; group 2). Results: SDB was identified in 79% of the SCD group. As compared with the uncomplicated OSAS group, the SCD with OSAS group displayed nocturnal desaturation with lower nadir values, of longer duration, with a 4-fold increased risk for oxygen desaturation below 85%, higher percentage of total sleep time with end-tidal carbon dioxide (ET CO2) values > 50 mm Hg, with a 3.7-fold increased risk for spending more than 25% of total sleep time with ET CO2 more than 50 mm Hg and higher peak ET CO2 with a 7-fold increase for peak ET CO2 above 53 mm Hg. Conclusions: Children with SCD suspicious of SDB may have not only a higher incidence of OSAS, but also more severe nocturnal desaturation and hypercapnia as compared with children with uncomplicated OSAS.