All-Cause Mortality in People with Co-Occurring Insomnia Symptoms and Sleep Apnea: Analysis of the Wisconsin Sleep Cohort

Bastien Lechat,1 Kelly A Loffler,1 Douglas M Wallace,2,3 Amy Reynolds,1 Sarah L Appleton,1 Hannah Scott,1 Andrew Vakulin,1,4 Nicole Lovato,1,4 Robert Adams,1,4 Danny J Eckert,1 Peter G Catcheside,1 Alexander Sweetman1,4 1Adelaide Institute for Sleep Health and FHMRI Sleep Health, Flinders University, Adelaide, South Australia, Australia; 2Department of Neurology, Sleep Medicine Division, University of Miami Miller School of Medicine, Miami, FL, USA; 3Neurology Service, Bruce W. Carter Department of Veterans Affairs Medical Centre, Miami, FL, USA; 4National Centre for Sleep Health Services Research: A NHMRC Centre of Research Excellence, Flinders University, Adelaide, South Australia, AustraliaCorrespondence: Bastien Lechat, Adelaide Institute for Sleep Health and Flinders Health and Medical Research Institute: Sleep Health, Level 2A, Mark Oliphant Building, 5 Laffer Drive, Flinders University, Bedford Park, South Australia, 5042, Australia, Email bastien.lechat@flinders.edu.auPurpose: Insomnia symptoms and sleep apnea frequently co-occur and are associated with worse sleep, daytime function, mental health and quality of life, compared to either insomnia or obstructive sleep apnea (OSA) alone. This study aimed to investigate the association of symptoms of co-morbid insomnia and sleep apnea (COMISA) with all-cause mortality.Patients and Methods: Wisconsin Sleep Cohort data were analysed to assess potential associations between COMISA symptoms and all-cause mortality. Nocturnal insomnia symptoms were defined as difficulties initiating sleep, maintaining sleep, and/or early morning awakenings “often” or “almost always”, and/or regular sedative-hypnotic medicine use. OSA was defined as an apnea-hypopnea index ≥ 5/hr sleep. Participants were classified as having neither insomnia symptoms nor OSA, insomnia symptoms alone, OSA alone, or COMISA symptoms. Associations between the four groups and all-cause mortality over 20 years of follow-up were examined via multiv