Potential antidepressant overtreatment associated with office use of brief depression symptom measures

Background: Use of brief depression symptom measures for identifying or screening cases may help to address depression undertreatment, but whether it also leads to diagnosis and treatment of patients with few or no symptoms-a group unlikely to have major depression or benefit from antidepressants-is unknown. We examined the associations of use of a brief depression symptom measure with depression diagnosis and antidepressant recommendation and prescription among patients with few or no depression symptoms.

Methods: We conducted exploratory observational analyses of data from a randomized trial of depression engagement interventions conducted in primary care offices in California. Analyses focused on participants scoring <10 on a study-administered 9-item Patient Health Questionnaire (PHQ-9) (completed immediately before an office visit and not disclosed to the provider) with complete chart review data (n = 595). We reviewed visit notes for evidence of practice administration of a brief symptom measure (independent of the trial) and whether the provider (1) diagnosed depression or (2) recommended and/or prescribed an antidepressant.

Results: Among the 545 patients without a practice-administered measure, 57 (10.5%) had a visit diagnosis of depression; 9 (1.6%) were recommended and another 21 (3.8%) prescribed an antidepressant. Among the 50 patients (8.4% of total sample) with a practice-administered measure, 10 (20%) had a visit diagnosis of depression; 6 (12%) were recommended and another 6 (12%) prescribed an antidepressant. Adjusting for nesting within providers, trial intervention, stratification variables, and sample weighting, use of a brief symptom measure was associated with depression diagnosis (adjusted odds ratio, 3.2; 95% confidence interval, 1.1-9.2) and antidepressant recommendation and/or prescription (adjusted odds ratio, 3.80; 95% confidence interval, 1.0-13.9). Analyses using progressively lower PHQ-9 thresholds (<9 to <5) and examining antidepressant prescription alone yielded consistent findings. Analyses by practice-administered measure (PHQ-9 vs PHQ-2) indicated the study findings were largely associated with PHQ-9 use.

Conclusions: These exploratory findings suggest administration of brief depression symptom measures, particularly the PHQ-9, may be associated with depression diagnosis and antidepressant recommendation and prescription among patients unlikely to have major depression. If these findings are confirmed, researchers should investigate the balance of benefits and risks (eg, overdiagnosis of depression and overtreatment with antidepressants) associated with use of a brief symptom measure.