Table 1.

Summary of included studies examining cardiovascular outcomes of sleep-disordered breathing in children with Down syndrome.

Study	Year	Title	Design	Aim
O’Driscoll et al.	2012	Cardiac and sympathetic activation are reduced in children with Down Syndrome and sleep disordered breathing	Case-control	Test hypotheses that (1) the cardiovascular response at obstructive event termination in children with DS is reduced compared with control children; (2) that this is reflected in more prolonged oxygen desaturation following obstructive events; and (3) that overnight sympathetic activity is lower in children with DS compared with control children.
Goffinski et al.	2014	Obstructive sleep apnea in young infants with Down Syndrome evaluated in a Down Syndrome specialty clinic	Retrospective cohort	To explore OSA among a sample of young infants with DS at a specialty clinic.
Konstantinopoulou et al.	2015	Relationship between obstructive sleep apnea, cardiac complications, and sleepiness in children with Down Syndrome	Randomized, double-blind, controlled trial	To determine if presence/severity of OSAS was associated with cardiovascular dysfunction in children with DS, and to assess response to continuous positive airway pressure treatment.
Sawatari et al.	2015	A nationwide cross-sectional study on congenital heart diseases and symptoms of sleep-disordered breathing among Japanese Down’s Syndrome people	Cross-sectional survey	To investigate the prevalence of SDB symptoms and congenital heart disease and to establish the relationship between SDB and congenital heart disease in Japanese DS individuals using data from a nationwide survey.
Bassam et al.	2021	Nocturnal dipping of heart rate is impaired in children with Down Syndrome and sleep disordered breathing	Matched cohort	To compare nocturnal dipping of HR and pulse transit time (PTT, surrogate inverse measure of BP change) in children with DS and SDB to those of typically developing children with and without SDB.
Walter et al.	2024	The surge in heart rate and blood pressure at respiratory event termination is dampened in children with Down Syndrome	Matched cohort	To compare cardiovascular autonomic function in children with DS and TD children matched for SDB severity, age and sex by analyzing the changes in HR and pulse transit time (PTT; a surrogate inverse measure of BP changes) associated with obstructive and central respiratory events during sleep stages.
Walter et al.	2025	Sleep apnea–specific hypoxic burden in children with Down Syndrome and typically developing children.	Matched cohort	Assess whether hypoxic burden (a metric integrating the frequency, depth, and duration of desaturations) is elevated in children with DS compared to typically developing children, and examine its relationship to heart rate variability (as an indicator of autonomic cardiovascular function).

Study details include author, year, title, study design, and primary objectives.