Abstract Introduction Obstructive sleep apnea (OSA) is highly prevalent in children with Down syndrome with estimated prevalence of 45-79%. Current OSA treatments for children with Down syndrome have limited effectiveness, as positive airway pressure therapy is poorly tolerated and adenotonsillectomy is not curative for most children with Down syndrome. The combination of atomoxetine and oxybutynin (ato-oxy) is a promising treatment for OSA in children with Down syndrome. Studies of ato-oxy (and the related treatment AD109, atomoxetine and aroxybutynin) in adults without Down syndrome have identified insomnia as a common adverse effect of treatment that may lead to discontinuation of treatment. Therefore, we evaluated the impact of ato-oxy on insomnia symptoms in children with Down syndrome and OSA. Methods The pediatric insomnia severity index (PISI) was used to evaluate insomnia symptoms in participants in an ongoing clinical trial of ato-oxy for OSA for children (age 6-17 years) with Down syndrome. Participants received 6 months of ato-oxy treatment (0.5 mg/kg atomoxetine and 5 mg oxybutynin). Paired t-tests were used to compare PISI scores at baseline and after treatment. Results 12 participants had data at both baseline and after 6 months of ato-oxy. Baseline sleep onset problem score was 5 ± 3.7 which improved to 3.3 ± 2.0 following ato-oxy treatment (p=0.04). Baseline sleep maintenance problem score was 6 ± 3.0 and improved to 3.4 ± 1.9 following ato-oxy treatment (p=0.005). Conclusion In contrast to ato-oxy treatment in typically developing adults, OSA treatment with ato-oxy in children with Down syndrome showed improvement in insomnia symptoms. Ato-oxy may be particularly beneficial for children with Down syndrome and comorbid insomnia and OSA, particularly as positive airway pressure therapy is often associated with worsened insomnia. These results also highlight the need for studies in special populations as results in typically developing populations may not be generalizable to special populations. Support (if any) Funding provided by NIH (HL151254 and HD109777) and PCORI (IDD-2024C1-37111). All statements in this report, including its findings and conclusions, are solely those of the authors and do not necessarily represent the views of the Patient-Centered Outcomes Research Institute (PCORI), its Board of Governors or Methodology Committee.
Combs et al. (Fri,) studied this question.