title: Gas exchange and exercise capacity affect neurocognitive performance in patients with lung disease.
abstract: OBJECTIVE
  This study examined the relationship between cognitive functioning and the severity of underlying lung disease in patients awaiting lung transplantation.
  
  
  METHODS
  Ninety-four patients with end-stage lung disease completed a test battery to assess cognitive performance in two domains: executive functioning/attention (Trails A and B, COWA, Animal Naming, Stroop Color-Word Test, Digit Symbol, and the 2 & 7 Test) and verbal memory (Digit Span-Backward and Forward, WMS-R Logical Memory and Paired Verbal Associates).
  
  
  RESULTS
  Thirty-seven percent of the patients demonstrated moderate to severe cognitive impairment data on two or more tests. Adjusting for age and education, there were no statistically significant differences on executive functioning or verbal memory as a function of specific lung disease diagnosis. Lower PCO2 values were associated with better cognitive performance on latent measures of executive functioning and attention (p = .006) and verbal memory (p = .009), whereas higher PO2 values tended to be associated with better performance on the executive functioning/attention measure (p = .064). Distance walked in 6 minutes was positively related to verbal memory (p < .023).
  
  
  CONCLUSIONS
  Impaired neurocognitive functioning may be relatively common in patients awaiting lung transplantation and is associated with ineffective pulmonary gas exchange and reduced exercise tolerance.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: Priti I
authors.initials: PI
authors.lastname: Parekh
authors.forename: James A
authors.initials: JA
authors.lastname: Blumenthal
authors.forename: Michael A
authors.initials: MA
authors.lastname: Babyak
authors.forename: Rick
authors.initials: R
authors.lastname: LaCaille
authors.forename: Sarah
authors.initials: S
authors.lastname: Rowe
authors.forename: Liz
authors.initials: L
authors.lastname: Dancel
authors.forename: Robert M
authors.initials: RM
authors.lastname: Carney
authors.forename: R Duane
authors.initials: RD
authors.lastname: Davis
authors.forename: Scott
authors.initials: S
authors.lastname: Palmer
mesh_terms: D000328:Adult; D003071:Cognition / Q000502:physiology*; D005080:Exercise Test; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D006801:Humans; D008171:Lung Diseases / Q000503:physiopathology / Q000523:psychology / Q000601:surgery; D016040:Lung Transplantation; D008297:Male; D008568:Memory / Q000502:physiology*; D008875:Middle Aged; D011300:Preoperative Care; D011581:Psychological Tests; D011659:Pulmonary Gas Exchange / Q000502:physiology*; D012131:Respiratory Insufficiency / Q000503:physiopathology / Q000523:psychology* / Q000601:surgery; D012720:Severity of Illness Index