Abbreviated versions of the insomnia severity index to screen for comorbid insomnia among obstructive sleep apnea patients

Marcela Yanagimori; Mariana D Fernandes; Gustavo F Grad; Aline B Monare; Bianca M S P Garcia; Ivana Rosanelli; Paulo M M S Mariano; Sean P A Drummond; Denise M O'Driscoll; Bradley A Edwards; Geraldo Lorenzi-Filho; Pedro R Genta

doi:10.1016/j.sleep.2024.11.035

Abbreviated versions of the insomnia severity index to screen for comorbid insomnia among obstructive sleep apnea patients

Sleep Med. 2024 Nov 26:126:19-24. doi: 10.1016/j.sleep.2024.11.035. Online ahead of print.

Affiliations

¹ Unidade de Disturbios do Sono, Divisao de Pneumologia, Instituto do Coracao (InCor), Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, SP, Brazil. Electronic address: yanagimori.marcela@usp.br.
² Unidade de Disturbios do Sono, Divisao de Pneumologia, Instituto do Coracao (InCor), Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, SP, Brazil.
³ School of Psychological Sciences, Monash University, Melbourne, VIC, Australia.
⁴ Department of Respiratory and Sleep Medicine, Eastern Health, Melbourne, VIC, Australia; Eastern Health Clinical School, Monash University, Melbourne, VIC, Australia.
⁵ Department of Physiology, Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia; School of Psychological Sciences, Monash University, Melbourne, VIC, Australia.

PMID: 39615273
DOI: 10.1016/j.sleep.2024.11.035

Abstract

Study objectives: The comorbidity of insomnia and obstructive sleep apnea (COMISA) is common and associated with adverse clinical consequences. While insomnia is often underdiagnosed among individuals with OSA, the identification of insomnia among these individuals may lead to improved medical care. Our objective was to assess the performance of two simplified tools (insomnia severity index-2 (ISI-2) and ISI-3) to identify insomnia among individuals with OSA. We hypothesized that the ISI-2 and ISI-3 perform well to diagnose insomnia among individuals with OSA.

Methods: Four different cohorts of individuals with sleep disorders were studied. Cohorts 1,2 and 3 included individuals with OSA. Cohort 4 included individuals with insomnia only. The performance of ISI-2 and ISI-3 was compared to ISI-7-based diagnosis of insomnia using receiving operating characteristic curve analysis.

Results: Cohorts 1, 2, 3 and 4 included 490, 124, 39 and 118 individuals, respectively. Individuals from cohorts 1, 2 and 3 were middle-aged, obese and had severe OSA on average. Individuals from cohort 2 were predominantly male while from cohorts 3 and 4 were predominantly female. Individuals from cohort 4 were slightly younger, and eutrophic on average. Cohorts 3 and 4 had higher insomnia severity (ISI-7) than cohorts 1 and 2. Using cohort 1, the best cut-offs for ISI-2 and ISI-3 were ≥6 and ≥8, respectively. Area under the curve (AUC) for ISI-2 was .900, .951 and .893 among cohorts 1, 2 and 4, respectively. AUC for ISI-3 was .924, .961 and .936 among cohorts 1, 2 and 4, respectively.

Conclusion: ISI-2 and ISI-3 are accurate screening tools for insomnia among individuals with sleep disorders. Easy recognition of insomnia among individuals with COMISA may improve clinical outcomes.

Keywords: COMISA; ISI; Insomnia; OSA.