1234 Economic Burden of Comorbid Insomnia and Obstructive Sleep Apnea (COMISA) in the United States Military Health System

Abstract Introduction Insomnia and obstructive sleep apnea (OSA) are highly prevalent among active-duty U.S. military personnel, and co-occurrence of the conditions is common. Compared to either condition alone in civilian populations, comorbid insomnia and OSA (COMISA) is associated with worse health outcomes, greater healthcare resource utilization, and higher healthcare costs. The purpose of this study was to determine the economic burden of COMISA among active-duty military personnel. We hypothesized that relative to insomnia and OSA alone COMISA is associated with greater healthcare resource utilization and costs. Methods Data were derived from the Military Data Repository (MDR) from 2016-2021. Inclusion criteria were age < 65 years, active-duty military personnel, 12 months of continuous enrollment before and after insomnia or OSA diagnosis, and no evidence of prior insomnia or OSA. COMISA was defined as receipt of an insomnia diagnosis within 365 days of OSA diagnosis. Generalized linear models with log link were used to compare direct costs between individuals without sleep disorders, insomnia alone, OSA alone, or COMISA across multiple points of service: outpatient, inpatient, and emergency department (ED). Costs were adjusted for age, sex, military service, region, comorbidities and prior year costs. Results The final sample included n=183,961 active-duty military personnel without sleep disorders, n=40,278 with insomnia alone, n=27,103 with OSA alone, and n=3,956 with COMISA. Most participants were between ages 35-44 years (40.7%), and male (82.1%). Average adjusted outpatient costs were highest in the COMISA group (without sleep disorders: $4,036; insomnia alone: $9,940; OSA alone: $6,910; COMISA: $10,759; p< 0.001), as were average adjusted ED costs (without sleep disorders: $214; insomnia alone: $363; OSA alone: $395; COMISA: $500; p< 0.001), while average adjusted inpatient costs (without sleep disorders: $168; insomnia alone: $267; OSA alone: $3; COMISA: $169; p< 0.001) were highest in the insomnia group. Conclusion Relative to military personnel without sleep disorders, with insomnia alone, or with OSA alone, individuals with COMISA incur greater inpatient, outpatient, and ED costs. Future research should examine the effect of sleep disorders treatments on health and economic burden as well as military readiness in the U.S. military. Support (if any) U.S. Department of Defense, Military Health System Research Program, HT94022210006.