title: Developmental Trajectories of Impaired Community Functioning in Schizophrenia.
abstract: OBJECTIVE
  Community functioning is a core component of the functional deficits in schizophrenia, yet little systematic research on the origins of these functional deficits has been performed.
  
  
  OBJECTIVE
  To examine 3 key domains of community functioning--social activity, independent behavior, and functioning in school or work--before first hospitalization for schizophrenia and to determine whether these domains are familial.
  
  
  METHODS
  In this population-based, prospective study that included a sibling-control comparison, data from the Israeli National Draft Board Registry were linked with data from the Israeli Psychiatric Hospitalization Case Registry. The merged file included data for all male adolescents who visited the draft board and were followed up for as much as 25.4 years from draft board assessment (through the end of 2010). The 3 functional domains for cases, their unaffected siblings, and controls were compared by time between assessment and time to hospitalization. Analyses were conducted from March 13, 2014, to October 19, 2014.
  
  
  METHODS
  The trajectories and familiality of 3 key components of community functioning--social activity, independent behavior, and functioning in school or work--in the years preceding hospitalization for schizophrenia.
  
  
  RESULTS
  Participants included 723,316 Israeli male adolescents who underwent a mandatory behavioral assessment to determine eligibility for military service. Linkage identified 3929 individuals hospitalized for schizophrenia. Data for 338,550 sibling pairs, 1659 hospitalized with schizophrenia, were similarly ascertained. Among those with schizophrenia, impairments in social activity (effect size [d], 0.55) and functioning in school or work (d = 0.37) were recognizable up to 15 years before hospitalization. Independent behavior seemed preserved until the few years before first admission. For social activity, differences between cases and controls were progressively greater for patients admitted closer to time of testing (F = 115.33, P < .001). Unaffected siblings had small impairments compared with controls in social activity (F = 28.25, P < .001) and functioning in school or work scales (F = 14.77, P < .001). Group familial (sibling) correlations were relatively high for social activity (r = 0.40; 95% CI, 0.39-0.41) and functioning in school or work (r = 0.50; 95% CI, 0.49-0.51) but nil for independent behavior (r = 0; 95% CI, -0.01 to -0.01). Impairments in siblings had no progressive increase and were unrelated to their affected sibling's time of illness onset (time trend: social activity: F = 5.463, P = .02; independent behavior: F = 0.908, P = .34; and functioning in school or work: F = 1.386, P = .24).
  
  
  CONCLUSIONS
  Various components of impaired community functioning in schizophrenia followed different developmental trajectories. Our results indicate that impairments in social activity and functioning in school or work are familial.
authors.affiliation: Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York.|Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, New York.|Department of Psychiatry, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: Eva
authors.initials: E
authors.lastname: Velthorst
authors.affiliation: Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York.|Department of Preventive Medicine, Icahn School of Medicine at Mount Sinai, New York, New York.
authors.forename: Abraham
authors.initials: A
authors.lastname: Reichenberg
authors.affiliation: Department of Psychiatry, Sheba Medical Center, Tel-Hashomer, Israel.
authors.forename: Ori
authors.initials: O
authors.lastname: Kapra
authors.affiliation: Department of Psychiatry, Sheba Medical Center, Tel-Hashomer, Israel.
authors.forename: Shira
authors.initials: S
authors.lastname: Goldberg
authors.affiliation: Department of Psychiatry, Icahn School of Medicine at Mount Sinai, New York, New York.|Department of Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York.
authors.forename: Menachem
authors.initials: M
authors.lastname: Fromer
authors.affiliation: Department of Psychiatry, Sheba Medical Center, Tel-Hashomer, Israel.
authors.forename: Eyal
authors.initials: E
authors.lastname: Fruchter
authors.affiliation: Department of Psychiatry, Sheba Medical Center, Tel-Hashomer, Israel.
authors.forename: Karen
authors.initials: K
authors.lastname: Ginat
authors.affiliation: Department of Psychiatry, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: Lieuwe
authors.initials: L
authors.lastname: de Haan
authors.affiliation: Department of Psychiatry, Sheba Medical Center, Tel-Hashomer, Israel.
authors.forename: Michael
authors.initials: M
authors.lastname: Davidson
authors.affiliation: Department of Psychiatry, Sheba Medical Center, Tel-Hashomer, Israel.
authors.forename: Mark
authors.initials: M
authors.lastname: Weiser
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D018450:Disease Progression; D004651:Employment; D006760:Hospitalization; D006801:Humans; D007557:Israel; D008137:Longitudinal Studies; D008297:Male; D011446:Prospective Studies; D012042:Registries; D012559:Schizophrenia; D012565:Schizophrenic Psychology; D012574:Schools; D035781:Siblings; D012919:Social Behavior; D058992:Social Participation; D055815:Young Adult