Examining the impact of multilevel upper airway surgery on the obstructive sleep apnoea endotypes and their utility in predicting surgical outcomes.

BACKGROUND AND OBJECTIVE: Upper airway surgery for obstructive sleep apnoea (OSA) is an alternative treatment for patients who are intolerant of continuous positive airway pressure (CPAP). However, upper airway surgery has variable treatment efficacy with no reliable predictors of response. While we now know that there are several endotypes contributing to OSA (i.e., upper airway collapsibility, airway muscle response/compensation, respiratory arousal threshold and loop gain), no study to date has examined: (i) how upper airway surgery affects all four OSA endotypes, (ii) whether knowledge of baseline OSA endotypes predicts response to surgery and (iii) whether there are any differences when OSA endotypes are measured using the CPAP dial-down or clinical polysomnographic (PSG) methods. METHODS: We prospectively studied 23 OSA patients before and ≥3 months after multilevel upper airway surgery. Participants underwent clinical and research PSG to measure OSA severity (apnoea-hypopnoea index [AHI]) and endotypes (measured in supine non-rapid eye movement [NREM]). Values are presented as mean ± SD or median (interquartile range). RESULTS: Surgery reduced the AHITotal (38.7 [23.4 to 79.2] vs. 22.0 [13.3 to 53.5] events/h; p = 0.009). There were no significant changes in OSA endotypes, however, large but variable improvements in collapsibility were observed (CPAP dial-down method: ∆1.9 ± 4.9 L/min, p = 0.09, n = 21; PSG method: ∆3.4 [-2.8 to 49.0]%Veupnoea , p = 0.06, n = 20). Improvement in collapsibility strongly correlated with improvement in AHI (%∆AHISupineNREM vs. ∆collapsibility: p < 0.005; R2  = 0.46-0.48). None of the baseline OSA endotypes predicted response to surgery. CONCLUSION: Surgery unpredictably alters upper airway collapsibility but does not alter the non-anatomical endotypes. There are no baseline predictors of response to surgery.

AYA 'Can-Sleep' programme: protocol for a stepped-care, cognitive behavioural therapy-based approach to the management of sleep difficulties in adolescents and young adults with cancer.

BACKGROUND: Sleep problems are reported in up to 50% of adolescents and young adults (AYA) with cancer. Cognitive behavioural therapy for insomnia (CBTi) is considered the gold-standard treatment. In the AYA population, CBTi is associated with improvements in insomnia, daytime sleepiness, fatigue and quality of life. In adults, stepped-care interventions can improve accessibility to CBTi. This study aims to evaluate the acceptability and feasibility of a stepped-care CBTi programme in AYA with cancer. METHODS AND ANALYSIS: AYA (target N = 80) aged 16-25 with a diagnosis of cancer will be screened using the Insomnia Severity Index (ISI) and Epworth Sleepiness Scale (ESS). When sleep difficulties are identified by the ISI and/or ESS, they will be screened for obstructive sleep apnoea and restless leg syndrome and referred to a sleep service if indicated. The remainder with sleep difficulties will be offered a stepped-care sleep programme including CBT self-management and coaching (first step). Participants will then be rescreened at 5 weeks, and those with ongoing sleep difficulties will be offered individualised CBT (second step). Recruitment and retention rates, adherence to intervention and time taken to deliver screening and intervention will be collected to assess the feasibility of the programme. AYA and clinicians will complete evaluation surveys to assess the acceptability of the AYA Can-Sleep programme. DISCUSSION: We seek to contribute to the evidence base regarding screening and treatment of sleep difficulties in the AYA population by implementing the AYA Can-Sleep programme and determining its feasibility and acceptability as an approach to care in an Adolescent & Young Adult Cancer Service.

A randomized controlled trial of oxygen therapy for patients who do not respond to upper airway surgery for obstructive sleep apnea.

STUDY OBJECTIVES: We aimed to determine whether patients diagnosed with obstructive sleep apnea (OSA) who fail to respond to upper airway surgery may be successfully treated with supplemental oxygen and whether we could identify baseline physiologic endotypes (ie, collapsibility, loop gain, arousal threshold, and muscle compensation) that predict response to oxygen therapy. METHODS: We conducted a single night, randomized double-blinded cross over trial in which patients with OSA who failed to respond to upper airway surgery were treated on separate nights with oxygen therapy (4 L/min) or placebo (medical air). Effect of oxygen/air on OSA on key polysomnography outcomes were assessed: apnea-hypopnea index (AHI), AHI without desaturation (ie, flow-based AHI), arousal index, and morning blood pressure. OSA endotypes were estimated from the polysomnography signals to determine whether baseline OSA physiology could be used to predict response to oxygen therapy. RESULTS: There was a statistically significant reduction in AHI and flow-based AHI on oxygen vs placebo (flow-based AHI: 42.4 ± 21.5 vs 30.5 ± 17.1 events/h, P = .008). Arousal index was also reduced on oxygen vs placebo (41.1 ± 19.5 vs 33.0 ± 15.3 events/h, P = .006). There was no significant difference in morning blood pressure between oxygen and placebo. Although 7 of 20 individuals experienced a 50% reduction or greater in flow-based AHI on oxygen (responders), there was no difference in the baseline OSA endotypes (or clinical characteristics) between responders and nonresponders. CONCLUSIONS: Our findings demonstrate that a proportion of patients who fail to respond to upper airway surgery for OSA respond acutely to treatment with supplemental oxygen. CLINICAL TRIAL REGISTRATION: Registry: Australian New Zealand Clinical Trials Registry; Name: Oxygen therapy for treating patients with residual obstructive sleep apnea following upper airway surgery; URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=373566; Identifier: ACTRN12617001361392.