Role of endothelial dysfunction in sleep-disordered breathing in egyptian children with sickle cell disease

Endothelial dysfunction is an integral pathophysiologic mechanism in sickle cell disease (SCD), and can lead to many complications. Sleep-disordered breathing (SDB) is a SCD complication with diverse incidence and pathophysiology. This study aimed to determine the prevalence of SDB in children with SCD and to assess its relation to endothelial dysfunction.

Sixty children with SCD and 60 healthy controls were enrolled. The levels of TNF-α, IL-6, and IL-17A were evaluated in the entire cohort using enzyme-linked immunosorbent assay (ELISA) kits. Polysomnography (PSG) was performed for all SCD patients after completion of the Pediatric Sleep Questionnaire (PSQ).

TNF-α, IL-6, and IL-17A levels were significantly greater in children with SCD than in controls (p-values < 0.001, < 0.001, and 0.006, respectively). The PSQ revealed symptoms suggestive of SDB in 50 children with SCD (83.3%), and PSG revealed obstructive sleep apnea (OSA) in 44 children with SCD (73.3%); 22 patients had mild OSA, and 22 had moderate-to-severe OSA according to the apnea-hypopnea index (AHI). TNF-α was significantly greater in SCD children who reported heavy or loud breathing, trouble breathing or struggle to breathe, and difficulty waking up in the morning (p-values = 0.002, 0.002, and 0.031, respectively). The IL-6 levels were significantly greater in SCD children who stopped growing normally (p-value = 0.002). The levels of IL-6 and IL-17A were significantly greater in SCD children with morning headaches (p-values = 0.007 and 0.004, respectively).

Children with SCD showed a high prevalence of SDB with significantly elevated levels of markers of endothelial function, highlighting the interplay of SDB and endothelial dysfunction in SCD.