title: Can a prediction model combining self-reported symptoms, sociodemographic and clinical features serve as a reliable first screening method for sleep apnea syndrome in patients with stroke?
abstract: OBJECTIVE
  To determine whether a prediction model combining self-reported symptoms, sociodemographic and clinical parameters could serve as a reliable first screening method in a step-by-step diagnostic approach to sleep apnea syndrome (SAS) in stroke rehabilitation.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  Rehabilitation center.
  
  
  METHODS
  Consecutive sample of patients with stroke (N=620) admitted between May 2007 and July 2012. Of these, 533 patients underwent SAS screening. In total, 438 patients met the inclusion and exclusion criteria.
  
  
  METHODS
  Not applicable.
  
  
  METHODS
  We administered an SAS questionnaire consisting of self-reported symptoms and sociodemographic and clinical parameters. We performed nocturnal oximetry to determine the oxygen desaturation index (ODI). We classified patients with an ODI ≥15 as having a high likelihood of SAS. We built a prediction model using backward multivariate logistic regression and evaluated diagnostic accuracy using receiver operating characteristic analysis. We calculated sensitivity, specificity, and predictive values for different probability cutoffs.
  
  
  RESULTS
  Thirty-one percent of patients had a high likelihood of SAS. The prediction model consisted of the following variables: sex, age, body mass index, and self-reported apneas and falling asleep during daytime. The diagnostic accuracy was .76. Using a low probability cutoff (0.1), the model was very sensitive (95%) but not specific (21%). At a high cutoff (0.6), the specificity increased to 97%, but the sensitivity dropped to 24%. A cutoff of 0.3 yielded almost equal sensitivity and specificity of 72% and 69%, respectively. Depending on the cutoff, positive predictive values ranged from 35% to 75%.
  
  
  CONCLUSIONS
  The prediction model shows acceptable diagnostic accuracy for a high likelihood of SAS. Therefore, we conclude that the prediction model can serve as a reasonable first screening method in a stepped diagnostic approach to SAS in stroke rehabilitation.
authors.affiliation: Heliomare Research and Development, Wijk aan Zee, The Netherlands; Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands. Electronic address: j.aaronson@heliomare.nl.
authors.forename: Justine A
authors.initials: JA
authors.lastname: Aaronson
authors.affiliation: Heliomare Research and Development, Wijk aan Zee, The Netherlands.
authors.forename: Janneke
authors.initials: J
authors.lastname: Nachtegaal
authors.affiliation: Heliomare Rehabilitation, Wijk aan Zee, The Netherlands.
authors.forename: Tijs
authors.initials: T
authors.lastname: van Bezeij
authors.affiliation: Heliomare Research and Development, Wijk aan Zee, The Netherlands; Heliomare Rehabilitation, Wijk aan Zee, The Netherlands.
authors.forename: Erny
authors.initials: E
authors.lastname: Groet
authors.affiliation: Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Winni F
authors.initials: WF
authors.lastname: Hofman
authors.affiliation: Department of Pulmonary Medicine, Medical Centre Alkmaar, Alkmaar, The Netherlands.
authors.forename: Joost G
authors.initials: JG
authors.lastname: van den Aardweg
authors.affiliation: Heliomare Research and Development, Wijk aan Zee, The Netherlands; Heliomare Rehabilitation, Wijk aan Zee, The Netherlands.
authors.forename: Coen A M
authors.initials: CA
authors.lastname: van Bennekom
mesh_terms: D017677:Age Distribution; D015992:Body Mass Index; D015331:Cohort Studies; D003863:Depression / Q000209:etiology; D005221:Fatigue / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D010092:Oximetry; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D057566:Self Report; D012680:Sensitivity and Specificity; D017678:Sex Distribution; D012891:Sleep Apnea Syndromes / Q000150:complications / Q000175:diagnosis*; D012913:Snoring / Q000209:etiology; D020521:Stroke / Q000150:complications*; D011795:Surveys and Questionnaires
keywords: Rehabilitation; Sleep apnea syndromes; Stroke