title: Four-Year Follow-up of Cognitive Behavioral Therapy in Persons at Ultra-High Risk for Developing Psychosis: The Dutch Early Detection Intervention Evaluation (EDIE-NL) Trial.
abstract: Previously, we demonstrated that cognitive behavior therapy for ultra-high risk (called CBTuhr) halved the incidence of psychosis over an 18-month period. Follow-up data from the same study are used to evaluate the longer-term effects at 4 years post-baseline.
  
  
  
  The Dutch Early Detection and Intervention Evaluation study was a randomized controlled trial of 196 UHR patients comparing CBTuhr with treatment-as-usual (TAU) for comorbid disorders with TAU only. Of the original 196 patients, 113 consented to a 4-year follow-up (57.7%; CBTuhr = 56 vs TAU = 57). Over the study period, psychosis incidence, remission from UHR status, and the effects of transition to psychosis were evaluated.
  
  
  
  The number of participants in the CBTuhr group making the transition to psychosis increased from 10 at 18-month follow-up to 12 at 4-year follow-up whereas it did not change in the TAU group (n = 22); this still represents a clinically important (incidence rate ratio [IRR] = 12/22 = 0.55) and significant effect (F(1,5) = 8.09, P = .03), favoring CBTuhr. The odds ratio of CBTuhr compared to TAU was 0.44 (95% CI: 0.24-0.82) and the number needed to treat was 8. Moreover, significantly more patients remitted from their UHR status in the CBTuhr group (76.3%) compared with the TAU group (58.7%) [t(120) = 2.08, P = .04]. Importantly, transition to psychosis was associated with more severe psychopathology and social functioning at 4-year follow-up.
  
  
  
  CBTuhr to prevent a first episode of psychosis in persons at UHR of developing psychosis is still effective at 4-year follow-up. Our data also show that individuals meeting the formal criteria of a psychotic disorder have worse functional and social outcomes compared with non-transitioned cases.
  
  
  
  The trial is registered at Current Controlled Trials as trial number ISRCTN21353122 (http://controlled-trials.com/ISRCTN21353122/gaag).
authors.affiliation: Department of Psychosis Research, Parnassia Psychiatric Institute, The Hague, The Netherlands; h.ising@parnassia.nl.
authors.forename: Helga K
authors.initials: HK
authors.lastname: Ising
authors.affiliation: Department of Psychiatry, Academic Medical Center, Amsterdam, The Netherlands;
authors.forename: Tamar C
authors.initials: TC
authors.lastname: Kraan
authors.affiliation: Department of Psychosis Research, Parnassia Psychiatric Institute, The Hague, The Netherlands; Department of Clinical Psychology, VU University and EMGO Institute for Health and Care Research, Amsterdam, The Netherlands;
authors.forename: Judith
authors.initials: J
authors.lastname: Rietdijk
authors.affiliation: Department of Psychiatry, Academic Medical Center, Amsterdam, The Netherlands;
authors.forename: Sara
authors.initials: S
authors.lastname: Dragt
authors.affiliation: Child and Adolescent Department, University Medical Center, Utrecht, The Netherlands;
authors.forename: Rianne M C
authors.initials: RM
authors.lastname: Klaassen
authors.affiliation: Department of Research and Education, Friesland Mental Health Services, Leeuwarden, The Netherlands;
authors.forename: Nynke
authors.initials: N
authors.lastname: Boonstra
authors.affiliation: Department of Psychiatry, Academic Medical Center, Amsterdam, The Netherlands;
authors.forename: Dorien H
authors.initials: DH
authors.lastname: Nieman
authors.affiliation: Department of Psychiatry, Academic Medical Center, Amsterdam, The Netherlands;
authors.forename: Monique
authors.initials: M
authors.lastname: Willebrands-Mendrik
authors.affiliation: Department of Psychosis Research, Parnassia Psychiatric Institute, The Hague, The Netherlands;
authors.forename: David P G
authors.initials: DP
authors.lastname: van den Berg
authors.affiliation: Department of Psychiatry, Academic Medical Center, Amsterdam, The Netherlands;
authors.forename: Don H
authors.initials: DH
authors.lastname: Linszen
authors.affiliation: Department of Research and Education, Friesland Mental Health Services, Leeuwarden, The Netherlands;
authors.forename: Lex
authors.initials: L
authors.lastname: Wunderink
authors.affiliation: Department of Psychiatry, University Medical Center Groningen and University of Groningen, Groningen, The Netherlands;
authors.forename: Wim
authors.initials: W
authors.lastname: Veling
authors.affiliation: Department of Clinical Psychology, VU University and EMGO Institute for Health and Care Research, Amsterdam, The Netherlands; Department of Public Mental Health, Trimbos Institute (Netherlands Institute of Mental Health and Addiction), Utrecht, The Netherlands; Department of Epidemiology and Biostatistics, VU University Medical Center, Amsterdam, The Netherlands.
authors.forename: Filip
authors.initials: F
authors.lastname: Smit
authors.affiliation: Department of Psychosis Research, Parnassia Psychiatric Institute, The Hague, The Netherlands; Department of Clinical Psychology, VU University and EMGO Institute for Health and Care Research, Amsterdam, The Netherlands;
authors.forename: Mark
authors.initials: M
authors.lastname: van der Gaag
mesh_terms: D000328:Adult; D015928:Cognitive Behavioral Therapy / Q000379:methods*; D018450:Disease Progression; D042241:Early Diagnosis; D061345:Early Medical Intervention / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009426:Netherlands; D017063:Outcome Assessment, Health Care; D011618:Psychotic Disorders / Q000175:diagnosis / Q000517:prevention & control*; D012306:Risk; D055815:Young Adult
keywords: at-risk mental state; cognitive behavior therapy; prevention; schizophrenia; ultra-high risk