Stepped care management of insomnia co-occurring with sleep apnea: the AIR study protocol
Authors: Eldridge-Smith E. Devon , Manber Rachel , Tsai Sheila , Kushida Clete , Simmons Bryan , Johnson Rachel , Horberg Roxane , Depew Ann , Abraibesh Aysha , Simpson Norah , Strand Matthew , Espie Colin A. , Edinger Jack D. 
Published: September 2022

Abstract
Background
Obstructive sleep apnea (OSA) and insomnia are commonly co-occurring conditions that amplify morbidity and complicates the management of affected patients. Unfortunately, previous research provides limited guidance as to what constitutes the best and most practical management approach for this comorbid patient group. Some preliminary studies show that when cognitive behavioral insomnia therapy (CBT-I) is combined with standard OSA therapies for these patients, outcomes are improved. However, the dearth of trained providers capable of delivering CBT-I has long served as a pragmatic barrier to the widespread use of this therapy in clinical practice. The emergence of sophisticated online CBT-I (OCBT-I) programs could improve access, showing promising reductions in insomnia severity. Given its putative scalability and apparent efficacy, some have argued OCBT-I should represent a 1st-stage intervention in a broader stepped care model that allocates more intensive and less assessable therapist-delivered CBT-I (TCBT-I) only to those who show an inadequate response to lower intensity OCBT-I. However, the efficacy of OCBT-I as a 1st-stage therapy within a broader stepped care management strategy for insomnia comorbid with OSA has yet to be tested with comorbid OSA/insomnia patients.

Methods/design
This dual-site randomized clinical trial will use a Sequential Multiple Assignment Randomized Trial (SMART) design to test a stepped care model relative to standard positive airway pressure (PAP) therapy and determine if (1) augmentation of PAP therapy with OCBT-I improves short-term outcomes of comorbid OSA/insomnia and (2) providing a higher intensity 2nd-stage CBT-I to patients who show sub-optimal short-term outcomes with OCBT-I+PAP improves short and longer-term outcomes. After completing baseline assessment, the comorbid OSA/insomnia patients enrolled will be randomized to a 1st-stage therapy that includes usual care PAP + OCBT-I or UC (usual care PAP + sleep hygiene education). Insomnia will be reassessed after 8 weeks. OCBT-I recipients who meet “remission” criteria (defined as an Insomnia Severity Index score < 10) will continue PAP but will not be offered any additional insomnia intervention and will complete study outcome measures again after an additional 8 weeks and at 3 and 6 month follow-ups. OCBT-I recipients classified as “unremitted” after 8 weeks of treatment will be re-randomized to a 2nd-stage treatment consisting of continued, extended access to OCBT-I or a switch to TCBT-I. Those receiving the 2nd-stage intervention as well as the UC group will be reassessed after another 8 weeks and at 3- and 6-month follow-up time points. The primary outcome will be insomnia remission. Secondary outcomes will include subjective and objective sleep data, including sleep time, sleep efficiency, fatigue ratings, PAP adherence, sleepiness ratings, sleep/wake functioning ratings, and objective daytime alertness.

Discussion
This study will provide new information about optimal interventions for patients with comorbid OSA and insomnia to inform future clinical decision-making processes.

Trial registration
ClinicalTrials.gov, NCT03109210, registered on April 12, 2017, prospectively registered.