title: Use of antidepressant medications: are there differences in psychiatric visits among patient treatments in the Veterans Administration?
abstract: BACKGROUND
  Information on the effectiveness of newer antidepressants like serotonin-norepinephrine reuptake inhibitors in terms of healthcare utilization is limited. Treatment guidelines affect evaluation. Second-line medications are usually prescribed to patients with higher utilization.
  
  
  OBJECTIVE
  The objective of this study was to compare antidepressants within the Veterans Affairs (VA) healthcare system on the basis of the number of outpatient psychiatric visits for each class of antidepressants.
  
  
  METHODS
  We conducted a retrospective cohort design using precollected information from VA national databases from 1999 and 2000. The study identified 92,537 patients on serotonin specific reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), or tricyclic antidepressants (TCAs).
  
  
  METHODS
  We stratified individual patients by the number of visits in the baseline year for each medication class. For each stratum, we created a dichotomized variable YK: Yk = 1 if there is a reduction of K visits or more and 0 if there is no reduction. We calculated the odds of reduction of psychiatric visits among the 3 classes of antidepressants.
  
  
  RESULTS
  TCAs and SSRIs were associated with greater odds of reduction compared with SNRIs at the level of 1 through 10 or 11 visits, respectively. SNRIs were associated with greater odds of reduction in visits at the level of 14, 16, or more visits compared with SSRIs and TCAs, respectively (P <0.05). SSRIs were associated with greater odds of reduction compared with TCAs at the level of 1 to 11 visits (P <0.05); there were no significant differences between the 2 classes above 11 visits.
  
  
  CONCLUSIONS
  Effectiveness research using databases should consider how medications are prescribed within systems. Treatment guidelines result in differences in severity and utilization among users of different medications.
authors.affiliation: Health Outcomes Technologies, Health Services Department, Boston University School of Public Health, Boston, Massachusetts 02118, USA. hamed@bu.edu
authors.forename: Alaa
authors.initials: A
authors.lastname: Hamed
authors.forename: Austin
authors.initials: A
authors.lastname: Lee
authors.forename: Xinhua S
authors.initials: XS
authors.lastname: Ren
authors.forename: Donald R
authors.initials: DR
authors.lastname: Miller
authors.forename: Fran
authors.initials: F
authors.lastname: Cunningham
authors.forename: Huan
authors.initials: H
authors.lastname: Zhang
authors.forename: Lewis E
authors.initials: LE
authors.lastname: Kazis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000928:Antidepressive Agents / Q000145:classification / Q000627:therapeutic use*; D018687:Antidepressive Agents, Second-Generation / Q000627:therapeutic use; D000929:Antidepressive Agents, Tricyclic / Q000627:therapeutic use; D015331:Cohort Studies; D015897:Comorbidity; D016208:Databases, Factual; D003865:Major Depressive Disorder / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy*; D004363:Drug Utilization; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data; D006787:Hospitals, Veterans / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010044:Outpatient Clinics, Hospital / Q000706:statistics & numerical data*; D017367:Selective Serotonin Reuptake Inhibitors / Q000627:therapeutic use*; D014481:United States; D014493:United States Department of Veterans Affairs
chemical_list: D000928:Antidepressive Agents; D018687:Antidepressive Agents, Second-Generation; D000929:Antidepressive Agents, Tricyclic; D017367:Selective Serotonin Reuptake Inhibitors