Pulmonary Dysfunction Is Associated With Sleep Study Abnormalities in Children With Sickle Cell Disease: A Multicenter Study.

INTRODUCTION

Pulmonary dysfunction and sleep abnormalities are common in children with sickle cell disease (SCD) and are associated with worse clinical outcomes. Whether spirometry abnormalities are associated with polysomnography (PSG) findings remains unclear.

METHODS

We conducted a multicenter cross-sectional study of 109 children with SCD who underwent both spirometry and PSG at three accredited pediatric pulmonary centers. Associations between spirometry indices and PSG markers of hypoxemia were assessed using correlation and multivariable regression models.

RESULTS

Abnormal spirometry was frequent: 26% had reduced forced expiratory volume in 1 second (FEV1), and 21% had reduced forced vital capacity (FVC). PSG revealed an elevated obstructive apnea-hypopnea index in more than 50%, and nocturnal hypoxemia in 31% of the cohort. Univariate analysis showed that lower FEV1 and FVC were associated with increased odds of nocturnal hypoxemia. After adjustment for multiple confounders, FEV and FEV1% remained independently positively associated with the nocturnal hypoxemia marker, mean oxygen saturation (SpO2), but not with the percentage of total sleep time with oxygen saturation less than 90% (%TST90).

DISCUSSION: This is one of the first studies to demonstrate that impaired lung function correlates with nocturnal hypoxemia in pediatric SCD. Abnormal spirometry results may serve as a marker of nocturnal hypoxemia, and vice versa, enabling targeted interventions. Further prospective studies are needed to confirm these findings and to evaluate whether improving pulmonary function mitigates sleep-related complications in children with SCD.