Predictors of outcome in a primary care depression trial.
OBJECTIVE
Previous treatment trials have found that approximately one third of depressed patients have persistent symptoms. We examined whether depression severity, comorbid psychiatric illness, and personality factors might play a role in this lack of response.


METHODS
Randomized trial of a stepped collaborative care intervention versus usual care.


METHODS
HMO in Seattle, Wash.


METHODS
Patients with major depression were stratified into severe (N = 149) and mild to moderate depression (N = 79) groups prior to randomization.


METHODS
A multifaceted intervention targeting patient, physician, and process of care, using collaborative management by a psychiatrist and primary care physician.


RESULTS
Patients with more severe depression had a higher risk for panic disorder (odds ratio [OR], 5.8), loneliness (OR, 2.6), and childhood emotional abuse (OR, 2.1). Among those with less severe depression, intervention patients showed significantly improved depression outcomes over time compared with those in usual care (z = -3.06, P<.002); however, this difference was not present in the more severely depressed groups (z = 0.61, NS). Although the group with severe depression showed differences between the intervention and control groups from baseline to 3 months that were similar to the group with less severe depression (during the acute phase of the intervention), these differences disappeared by 6 months.


CONCLUSIONS
Initial depression severity, comorbid panic disorder, and other psychosocial vulnerabilities were associated with a decreased response to the collaborative care intervention. Although the intervention was appropriate for patients with moderate depression, individuals with higher levels of depression may require a longer continuation phase of therapy in order to achieve optimal depression outcomes.
Walker
E A
EA
Department of Psychiatry and Behavioral Sciences, University of Washington Medical School, Seattle, Wash. 98195, USA. edwalker@u.washington.edu
Katon
W J
WJ
Russo
J
J
Von Korff
M
M
Lin
E
E
Simon
G
G
Bush
T
T
Ludman
E
E
Unützer
J
J
D000328:Adult; D000928:Antidepressive Agents / Q000627:therapeutic use*; D002648:Child; D002649:Child Abuse / Q000523:psychology; D003131:Combined Modality Therapy; D003863:Depression / Q000150:complications / Q000188:drug therapy / Q000523:psychology / Q000628:therapy*; D005260:Female; D006279:Health Maintenance Organizations; D006801:Humans; D008132:Loneliness / Q000523:psychology; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D016584:Panic Disorder / Q000150:complications; D010346:Patient Care Management / Q000379:methods*; D010349:Patient Compliance / Q000523:psychology* / Q000706:statistics & numerical data; D011320:Primary Health Care; D011379:Prognosis; D011614:Psychotherapy, Brief; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014861:Washington
D000928:Antidepressive Agents