title: Subtypes of clients with serious mental illness and co-occurring disorders: latent-class trajectory analysis.
abstract: OBJECTIVE
  This study identified and characterized groups of clients who have serious mental illness and co-occurring substance use disorders.
  
  
  METHODS
  Substance abuse recovery of 177 clients with co-occurring disorders was followed for ten years with multiperspective ratings every six months. Latent-class trajectory analysis was used to identify subgroups; profile analysis was used to examine baseline risk factors and treatment participation.
  
  
  RESULTS
  Two ratings of substance abuse recovery-stage of treatment and abstinence-were highly concordant and identified the same four groups: early recovery, unstable recovery, late recovery, and no recovery. The early-recovery group was characterized by less severe substance use disorders at baseline and by use of clozapine. The unstable-recovery group was too small for statistical analyses. The late-recovery group was similar to the no-recovery group at baseline but participated more extensively in treatments, especially residential dual-diagnosis programs, during the first three years of follow-up.
  
  
  CONCLUSIONS
  Latent-class trajectory analysis based on ten-year trajectories of substance abuse recovery identified clinically meaningful groups among clients with serious mental illness and co-occurring substance use disorders. Profiles of the three most common groups suggest differential clinical approaches for each.
authors.affiliation: Dartmouth Psychiatric Research Center, 2 Whipple Pl., Suite 202, Lebanon, NH 03766, USA. haiyi.xie@dartmouth.edu
authors.forename: Haiyi
authors.initials: H
authors.lastname: Xie
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: McHugo
authors.forename: Robert E
authors.initials: RE
authors.lastname: Drake
mesh_terms: D000328:Adult; D017831:Diagnosis, Dual (Psychiatry); D005260:Female; D006801:Humans; D007407:Interviews as Topic; D008137:Longitudinal Studies; D008297:Male; D001523:Mental Disorders; D010361:Patients / Q000145:classification*; D011446:Prospective Studies; D012720:Severity of Illness Index; D019966:Substance-Related Disorders / Q000534:rehabilitation*