title: Patterns of health services use associated with Veterans Affairs outpatient substance-use treatment.
abstract: OBJECTIVE
  This study examined service use and costs associated with receiving intensive outpatient (IOP) substance-use treatment.
  
  
  METHODS
  Veterans Affairs national databases were used to identify all veterans receiving IOP substance-use treatment in fiscal year (FY) 1999. Changes in the use of health services (2 years pretreatment compared with 2 years posttreatment) were examined. Three IOP treatment groups were defined: (1) veterans attending 1-5 IOP visits (n=2,384), (2) 6-14 IOP visits (n=2,940), and (3) >or= 15 IOP visits (n=3,005). In addition, a demographically matched no-treatment group was defined as veterans in primary care with a substance-use diagnosis and no substance-use treatment in FY 1999 (n = 7,328). General medical, psychiatric, and substance-use encounters in inpatient and outpatient settings were retrieved for the 4 years. Generalized estimating equations analyses were used to compare changes in service use across the three IOP groups controlling for demographic characteristics and comorbidity.
  
  
  RESULTS
  Total outpatient visits increased in all three treatment groups after IOP, with the largest increase observed in the group with >or= 15 visits (mean visits = 5, 44, and 57, respectively). In comparison, total visits decreased in the no-treatment group (-7). This pattern was similar across settings (general medical, psychiatric, and substance use). Total inpatient days decreased among the four groups, with the no-treatment group having the least amount of decrease (mean change in days = .34, .32, .18, and .03, respectively). Analysis of cost data showed similar findings.
  
  
  CONCLUSIONS
  Results indicated that more intense IOP treatment is associated with increases in subsequent psychiatric, substance-use, medical, and total outpatient care and decreases in expensive inpatient care.
authors.affiliation: Veterans Affairs Health Services Research and Development, Center for Mental Health and Outcomes Research, Central Arkansas Veterans Healthcare System, 152/NLR, 2200 Fort Roots Drive, North Little Rock, Arkansas 72114, USA. steckertracy@uams.edu
authors.forename: Tracy
authors.initials: T
authors.lastname: Stecker
authors.forename: Geoffrey M
authors.initials: GM
authors.lastname: Curran
authors.forename: Xiaotong
authors.initials: X
authors.lastname: Han
authors.forename: Brenda M
authors.initials: BM
authors.lastname: Booth
mesh_terms: D000328:Adult; D000368:Aged; D000553:Ambulatory Care / Q000191:economics / Q000706:statistics & numerical data*; D015331:Cohort Studies; D005260:Female; D017048:Health Care Costs; D006296:Health Services / Q000191:economics / Q000706:statistics & numerical data*; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008605:Mental Health Services / Q000191:economics / Q000706:statistics & numerical data; D008875:Middle Aged; D010343:Patient Admission / Q000706:statistics & numerical data; D011320:Primary Health Care / Q000706:statistics & numerical data; D019966:Substance-Related Disorders / Q000191:economics / Q000453:epidemiology / Q000534:rehabilitation*; D014481:United States; D014600:Utilization Review / Q000706:statistics & numerical data; D014728:Veterans / Q000523:psychology* / Q000706:statistics & numerical data