title: Spontaneous improvement in both obstructive sleep apnea and cognitive impairment after stroke.
abstract: BACKGROUND
  Knowledge available about the relationship between obstructive sleep apnea (OSA) and cognitive impairment after stroke is limited. The evolution of OSA and cognitive performance after stroke is not sufficiently described.
  
  
  METHODS
  We prospectively enrolled and examined acute stroke patients without previously diagnosed OSA. The following information was collected: (1) demographics, (2) sleep cardio-respiratory polygraphy (PG) at 72 h, day seven, month three, and month 12 after stroke, (3) post-stroke functional disability tests at entry and at months three and 12, and (4) cognition (attention and orientation, memory, verbal fluency, language, and visual-spatial abilities) using the revised Addenbrooke's Cognitive Examination (ACE-R) at months three and 12.
  
  
  RESULTS
  Of 68 patients completing the study, OSA was diagnosed in 42 (61.8%) patients. The mean apnea/hypopnea index (AHI) at study entry of 21.0 ± 13.7 spontaneously declined to 11.6 ± 11.2 at month 12 in the OSA group (p < 0.0005). The total ACE-R score was significantly reduced at months three (p = 0.005) and 12 (p = 0.004) in the OSA group. Poorer performance on the subtests of memory at months 3 (p = 0.039) and 12 (p = 0.040) and verbal fluency at months 3 (p < 0.005) and 12 (p < 0.005) were observed in the OSA group compared to non-OSA group. Visual-spatial abilities in both the OSA (p = 0.001) and non-OSA (p = 0.046) groups and the total ACE-R score in the OSA (p = 0.005) and non-OSA (p = 0.002) groups improved.
  
  
  CONCLUSIONS
  A high prevalence of OSA and cognitive decline were present in patients after an acute stroke. Spontaneous improvements in both OSA and cognitive impairment were observed.
authors.affiliation: Department of Neurology, Faculty Hospital Ostrava, 17. Listopadu 1790, 708 52, Ostrava, Czech Republic. Electronic address: janaslonkova@seznam.cz.
authors.forename: J
authors.initials: J
authors.lastname: Slonkova
authors.affiliation: Department of Neurology, Faculty Hospital Ostrava, 17. Listopadu 1790, 708 52, Ostrava, Czech Republic; Faculty of Medicine, University of Ostrava, Syllabova 19, 703 00, Ostrava-jih, Czech Republic. Electronic address: michal.bar@fno.cz.
authors.forename: M
authors.initials: M
authors.lastname: Bar
authors.affiliation: Philosophical Faculty, Palacky University Olomouc, Krizkovskeho 512/10, 779 00, Olomouc, Czech Republic. Electronic address: Petr.nilius@gmail.com.
authors.forename: P
authors.initials: P
authors.lastname: Nilius
authors.affiliation: Department of Neurology, Faculty Hospital Ostrava, 17. Listopadu 1790, 708 52, Ostrava, Czech Republic. Electronic address: bea.jojo@seznam.cz.
authors.forename: D
authors.initials: D
authors.lastname: Berankova
authors.affiliation: Faculty of Economics, VSB - Technical University of Ostrava, Sokolska 33, Ostrava, 701 21, Czech Republic. Electronic address: dana.salounova@vsb.cz.
authors.forename: D
authors.initials: D
authors.lastname: Salounova
authors.affiliation: Department of Neurology, First Faculty of Medicine, Charles University in Prague, Prague, 128 21, Czech Republic. Electronic address: Ksonka@lf1.cuni.cz.
authors.forename: K
authors.initials: K
authors.lastname: Sonka
mesh_terms: D000328:Adult; D000368:Aged; D060825:Cognitive Dysfunction / Q000150:complications* / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D020127:Recovery of Function; D020181:Sleep Apnea, Obstructive / Q000150:complications* / Q000453:epidemiology; D020521:Stroke / Q000150:complications* / Q000453:epidemiology
keywords: Cognition; Obstructive sleep apnea; Stroke