title: Hospitalization of high and low inpatient service users before and after enrollment into Assertive Community Treatment teams: a naturalistic observational study.
abstract: BACKGROUND
  Assertive Community Treatment (ACT) is more successful in reducing hospitalization when baseline use is high. However, with a growing recovery-focus, ACT may be useful for people with severe mental illness who are difficult to engage but not high users of inpatient services. This study investigated hospitalization 2 years before and 2 years after ACT enrollment amongst patients both with and without high inpatient services use before enrollment into ACT.
  
  
  METHODS
  This naturalistic observational study included 142 patients from 12 different ACT teams throughout Norway. Of these, 74 (52 %) were high users of inpatient services before ACT. The teams assessed the patients upon enrollment using clinician-rated and self-reported questionnaires. Hospitalization data from 2 years before and 2 years after enrollment into ACT were obtained from the Norwegian Patient Registry. Linear mixed models were used to assess changes in hospitalization and to explore associations between these changes and patient characteristics.
  
  
  RESULTS
  When the participants enrolled into the ACT teams, high users of inpatient care were younger, more often living alone and more often subject to involuntary outpatient treatment than low users. The participants spent significantly fewer days in hospital during the 2 years of ACT follow-up compared to the 2 years before enrollment. The reduction was more evident amongst high users, whereas low users had an initial increase in inpatient days in the first year of ACT and a subsequent decrease in the second year. More severe negative symptoms and previous high use of inpatient care were associated with a reduction in both total and involuntary inpatient days. Additionally, a reduction in involuntary inpatient days was associated with being subject to involuntary outpatient treatment upon enrollment into ACT.
  
  
  CONCLUSIONS
  The findings in this study may suggest that ACT contributes to more appropriate use of inpatient care, possibly by reducing the presumably avoidable hospitalization of high users and increasing the presumably needed inpatient care of low users.
authors.affiliation: Department of Research and Development, Mental Health Services, Akershus University Hospital, Lørenskog, Norway ; Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: Hanne
authors.identifier: 0000-0003-3282-6918
authors.initials: H
authors.lastname: Clausen
authors.affiliation: National Centre for Dual Diagnosis, Innlandet Hospital Trust, Brumunddal, Norway ; Addiction Research, University of Oslo, Oslo, Norway.
authors.forename: Anne
authors.initials: A
authors.lastname: Landheim
authors.affiliation: National Centre for Dual Diagnosis, Innlandet Hospital Trust, Brumunddal, Norway.
authors.forename: Sigrun
authors.initials: S
authors.lastname: Odden
authors.affiliation: Institute of Clinical Medicine, University of Oslo, Oslo, Norway ; HØKH Research Centre, Akershus University Hospital, Lørenskog, Norway.
authors.forename: Jūratė
authors.initials: J
authors.lastname: Šaltytė Benth
authors.affiliation: Department of Research and Development, Mental Health Services, Akershus University Hospital, Lørenskog, Norway.
authors.forename: Kristin Sverdvik
authors.initials: KS
authors.lastname: Heiervang
authors.affiliation: National Centre for Dual Diagnosis, Innlandet Hospital Trust, Brumunddal, Norway.
authors.forename: Hanne Kilen
authors.initials: HK
authors.lastname: Stuen
authors.affiliation: Division of Psychiatry, University College London, London, UK.
authors.forename: Helen
authors.initials: H
authors.lastname: Killaspy
authors.affiliation: Department of Research and Development, Mental Health Services, Akershus University Hospital, Lørenskog, Norway ; Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: Torleif
authors.initials: T
authors.lastname: Ruud
keywords: Appropriate services; Assertive community treatment; High inpatient service use; Hospitalization