D1.480 - Polysomnographic phenotypes of sleep-disordered breathing in children with asthma: a systematic review

Sleep-disordered breathing (SDB) is common in children with asthma, yet its clinical assessment relies largely on the apnea–hypopnea index (AHI), which correlates poorly with symptoms and asthma morbidity. Polysomnography (PSG) provides multidimensional information on sleep and respiration, but PSG findings in pediatric asthma have not been systematically integrated into clinically meaningful phenotypes. The aim of this systematic review was to identify and classify polysomnographic phenotypes of SDB in children with asthma.

PubMed/MEDLINE, Embase and Web of Science were systematically searched from January 2000 to March 2025 for studies of children and adolescents (0–18 years) with asthma who underwent overnight PSG. Observational and interventional studies reporting respiratory events, sleep architecture, arousals or oxygenation were included. Study selection and data extraction were performed independently by two reviewers following PRISMA methodology. Due to heterogeneity in PSG metrics, a structured narrative synthesis was conducted. A total of 314 records were identified, 47 full-text articles were assessed for eligibility, and 22 studies were included in the final synthesis (16 observational, 6 interventional).

Phenotype-defining PSG patterns were identifiable in 11 of the 22 included studies. The remaining studies reported limited PSG metrics (often overall AHI ± oxygenation) insufficient for phenotype classification. Four recurrent PSG phenotypes of SDB were identified: (1) a REM-predominant obstructive phenotype (n=4 studies), (2) a sleep-fragmentation–dominant phenotype (n=3), (3) altered sleep architecture independent of AHI (n=3), and (4) a ventilatory control–altered phenotype, requiring confirmation  (n=1). REM-predominant and fragmentation phenotypes were associated with worse asthma control and increased exacerbation risk. Obesity, upper airway inflammation and poor asthma control consistently modified PSG patterns.

Sleep-disordered breathing in pediatric asthma comprises distinct polysomnographic phenotypes that extend beyond AHI-defined severity. A phenotype-based interpretation of PSG may better explain symptom burden and heterogeneity of asthma and should inform precision-based clinical assessment and future interventional studies.