Determinants of antidepressant treatment outcome.
OBJECTIVE
To understand the determinants of the outcome of an episode of major depression, including factors that affect receipt of guideline-consistent care and their subsequent effect on treatment outcomes, particularly relapse or recurrence. Results of previous studies are generalized to a population typical of depressed individuals in the United States, i.e., a cohort of antidepressant users with employer-provided health benefits.


METHODS
A quasi-experimental design was used to assess the determinants of the outcome of an episode of major depression. Healthcare utilization-based measures of treatment characteristics and outcomes were used.


METHODS
The final analytical file for this study contained data on 2917 patients who had an antidepressant prescription associated with an indicator of a depressive disorder. We identified relapse or recurrence of depression by (1) a new episode of antidepressant therapy, (2) suicide attempt, (3) psychiatric hospitalization, (4) mental health-related emergency department visits, or (5) electroconvulsive therapy. Antidepressant use patterns were used to construct a measure for adherence to treatment guidelines. Multivariate Cox proportional hazard and logit regression models were used to predict relapse/recurrence and adherence with treatment guidelines, respectively, for each patient.


RESULTS
Factors that affect relapse/recurrence include comorbidities, demographics, and adherence to treatment guidelines. Factors that affect adherence to treatment guidelines include choice of initial antidepressant drug, comorbidities, psychotherapy, and frequency of physician visits.


CONCLUSIONS
Adherence to treatment guidelines was associated with a significant reduction in the likelihood of relapse or recurrence of depression. Choice of initial antidepressant drug affects adherence to treatment guidelines.
Sood
N
N
Department of Economics, Indiana University, Purdue University at Indianapolis, USA.
Treglia
M
M
Obenchain
R L
RL
Dulisse
B
B
Melfi
C A
CA
Croghan
T W
TW
D000928:Antidepressive Agents / Q000627:therapeutic use*; D003625:Data Collection; D003866:Depressive Disorder / Q000188:drug therapy*; D017723:Drug Utilization Review; D017050:Episode of Care; D005260:Female; D006264:Health Benefit Plans, Employee; D006801:Humans; D008297:Male; D010349:Patient Compliance; D017410:Practice Guidelines as Topic; D012008:Recurrence; D016896:Treatment Outcome; D014481:United States
D000928:Antidepressive Agents