title: The impact of psychosis on the course of cognition: a prospective, nested case-control study in individuals at clinical high-risk for psychosis.
abstract: BACKGROUND
  Although cognitive deficits in patients with schizophrenia are rooted early in development, the impact of psychosis on the course of cognitive functioning remains unclear. In this study a nested case-control design was used to examine the relationship between emerging psychosis and the course of cognition in individuals ascertained as clinical high-risk (CHR) who developed psychosis during the study (CHR + T).
  
  
  METHODS
  Fifteen CHR + T subjects were administered a neurocognitive battery at baseline and post-psychosis onset (8.04 months, s.d. = 10.26). CHR + T subjects were matched on a case-by-case basis on age, gender, and time to retest with a group of healthy comparison subjects (CNTL, n = 15) and two groups of CHR subjects that did not transition: (1) subjects matched on medication treatment (i.e. antipsychotics and antidepressants) at both baseline and retesting (Meds-matched CHR + NT, n = 15); (2) subjects unmedicated at both assessments (Meds-free CHR + NT, n = 15).
  
  
  RESULTS
  At baseline, CHR + T subjects showed large global neurocognitive and intellectual impairments, along with specific impairments in processing speed, verbal memory, sustained attention, and executive function. These impairments persisted after psychosis onset and did not further deteriorate. In contrast, CHR + NT subjects demonstrated stable mild to no impairments in neurocognitive and intellectual performance, independent of medication treatment.
  
  
  CONCLUSIONS
  Cognition appears to be impaired prior to the emergence of psychotic symptoms, with no further deterioration associated with the onset of psychosis. Cognitive deficits represent trait risk markers, as opposed to state markers of disease status and may therefore serve as possible predictors of schizophrenia prior to the onset of the full illness.
authors.affiliation: Division of Psychiatry Research,The Zucker Hillside Hospital,North Shore - Long Island Jewish Health System (NS-LIJHS),Glen Oaks,NY,USA.
authors.forename: R E
authors.initials: RE
authors.lastname: Carrión
authors.affiliation: Division of Psychiatry Research,The Zucker Hillside Hospital,North Shore - Long Island Jewish Health System (NS-LIJHS),Glen Oaks,NY,USA.
authors.forename: D
authors.initials: D
authors.lastname: McLaughlin
authors.affiliation: Division of Psychiatry Research,The Zucker Hillside Hospital,North Shore - Long Island Jewish Health System (NS-LIJHS),Glen Oaks,NY,USA.
authors.forename: A M
authors.initials: AM
authors.lastname: Auther
authors.affiliation: Division of Psychiatry Research,The Zucker Hillside Hospital,North Shore - Long Island Jewish Health System (NS-LIJHS),Glen Oaks,NY,USA.
authors.forename: R
authors.initials: R
authors.lastname: Olsen
authors.affiliation: Division of Psychiatry Research,The Zucker Hillside Hospital,North Shore - Long Island Jewish Health System (NS-LIJHS),Glen Oaks,NY,USA.
authors.forename: C U
authors.initials: CU
authors.lastname: Correll
authors.affiliation: Division of Psychiatry Research,The Zucker Hillside Hospital,North Shore - Long Island Jewish Health System (NS-LIJHS),Glen Oaks,NY,USA.
authors.forename: B A
authors.initials: BA
authors.lastname: Cornblatt
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D003072:Cognition Disorders / Q000209:etiology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D062706:Prodromal Symptoms; D011446:Prospective Studies; D011618:Psychotic Disorders / Q000150:complications*; D012306:Risk; D055815:Young Adult
keywords: Clinical high risk; linear mixed-effects models; nested case-control study; neurocognition; prodromal; psychosis