title: Sleep and Cognitive Function in Multiple Sclerosis.
abstract: To examine associations between cognitive performance and polysomnographic measures of obstructive sleep apnea in patients with multiple sclerosis (MS).
  
  
  
  Participants underwent a comprehensive MS-specific cognitive testing battery (the Minimal Assessment of Cognitive Function in MS, or MACFIMS) and in-laboratory overnight PSG.
  
  
  
  In adjusted linear regression models, the oxygen desaturation index (ODI) and minimum oxygen saturation (MinO2) were significantly associated with performance on multiple MACFIMS measures, including the Paced Auditory Serial Addition Test (PASAT; 2-sec and 3-sec versions), which assesses working memory, processing speed, and attention, and on the Brief Visuospatial Memory Test-Revised, a test of delayed visual memory. The respiratory disturbance index (RDI) was also significantly associated with PASAT-3 scores as well as the California Verbal Learning Test-II (CVLT-II) Discriminability Index, a test of verbal memory and response inhibition. Among these associations, apnea severity measures accounted for between 12% and 23% of the variance in cognitive test performance. Polysomnographic measures of sleep fragmentation (as reflected by the total arousal index) and total sleep time also showed significant associations with a component of the CVLT-II that assesses response inhibition, explaining 18% and 27% of the variance in performance.
  
  
  
  Among patients with MS, obstructive sleep apnea and sleep disturbance are significantly associated with diminished visual memory, verbal memory, executive function (as reflected by response inhibition), attention, processing speed, and working memory. If sleep disorders degrade these cognitive functions, effective treatment could offer new opportunities to improve cognitive functioning in patients with MS.
  
  
  
  A commentary on this article appears in this issue on page 1489.
authors.affiliation: Department of Neurology, Multiple Sclerosis and Sleep Disorders Centers, University of Michigan, Ann Arbor, MI.
authors.forename: Tiffany J
authors.initials: TJ
authors.lastname: Braley
authors.affiliation: Center for Clinical Outcomes Development and Application (CODA), Department of Physical Medicine and Rehabilitation, University of Michigan.
authors.forename: Anna L
authors.initials: AL
authors.lastname: Kratz
authors.affiliation: Department of Neurology and Sleep Disorders Center, University of Michigan.
authors.forename: Neeraj
authors.initials: N
authors.lastname: Kaplish
authors.affiliation: Department of Neurology and Sleep Disorders Center, University of Michigan.
authors.forename: Ronald D
authors.initials: RD
authors.lastname: Chervin
mesh_terms: D001288:Attention; D003071:Cognition; D003072:Cognition Disorders / Q000150:complications / Q000503:physiopathology / Q000523:psychology; D056344:Executive Function; D005260:Female; D006801:Humans; D007802:Language; D016014:Linear Models; D008297:Male; D008569:Memory Disorders / Q000150:complications / Q000523:psychology; D008570:Memory, Short-Term; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000150:complications / Q000503:physiopathology* / Q000523:psychology*; D009483:Neuropsychological Tests; D010100:Oxygen / Q000378:metabolism; D012890:Sleep; D020181:Sleep Apnea, Obstructive / Q000150:complications* / Q000503:physiopathology / Q000523:psychology; D065852:Spatial Memory; D013997:Time Factors
chemical_list: D010100:Oxygen
keywords: MS; cognitive dysfunction; multiple sclerosis; sleep apnea; sleep disorders