Patient-assessed versus physician-assessed disease severity and outcome in patients with nonspecific pain associated with major depressive disorder

Abstract

Objectives: This post hoc analysis compared how patients and physicians estimate disease severity and global improvement during 8 weeks of treatment for major depressive disorder (MDD) with associated nonspecific pain. In addition, predictors of pain and depression were identified.

Method: Data were derived from a double-blind, placebo-controlled, multicenter, European study (conducted from May 2005 to May 2006) in adult outpatients with MDD (DSM-IV criteria) and moderate pain not attributable to a diagnosed organic pain syndrome (Brief Pain Inventory-Short Form [BPI-SF] average pain score ≥ 3). Patients were randomly assigned to duloxetine 60 mg/day or placebo and treated for 8 weeks. Physicians were asked to rate severity of depression by using the Montgomery-Asberg Depression Rating Scale (MADRS) and the Clinical Global Impressions-Severity of Illness (CGI-S) and CGI-Improvement (CGI-I) scales. Patients were asked to assess pain using the BPI-SF, psychological symptomatology (9 domains including depression) with the Symptom Checklist-90-Revised (SCL-90-R), and overall improvement with the Patient Global Impression of Improvement (PGI-I). Multivariate linear regressions were performed as post hoc analyses to identify predictors of disease assessment at baseline and at the end of the study using a last-observation-carried-forward approach.

Results: All SCL-90-R domains improved during the 8 weeks of treatment. At baseline, the MADRS was associated only with the SCL-90-R obsessive-compulsive score, while the SCL-90-R depression score was associated with the BPI-SF average pain score and with many SCL-90-R subscores. The global impression of improvement was rated higher by the physicians than by the patients. At the end of the study, CGI-I was significantly associated with a decrease in depression severity (MADRS; p < .0001), younger age (p = .0005), and a decrease of the SCL-90-R interpersonal sensitivity score (p = .0359), but not with BPI-SF average pain. In contrast, patient-rated PGI-I was significantly associated with the SCL-90-R depressive domain (p < .0001), BPI-SF average pain (p = .0003), and the SCL-90-R anxiety domain (p = .0041) scores.

Conclusion: In patients with MDD associated with at least moderate nonspecific pain, physicians consider mainly the change in depressive symptoms as measured by MADRS in their CGI-I ratings, while patients also consider pain, depression, and anxiety in their PGI-I ratings. When treating depression and assessing treatment outcome, a broad spectrum of symptoms needs to be monitored.

Trial registration: clinicaltrials.gov Identifier: NCT00191919.

Figure 1

Clinical Global Impression of Improvement (A) Versus Patient Global Impression of Improvement (B) ^aCochran-Mantel-Haenszel test stratified by study center (full analysis set, last observation carried forward).

Figure 1

Clinical Global Impression of Improvement (A) Versus Patient Global Impression of Improvement (B) ^aCochran-Mantel-Haenszel test stratified by study center (full analysis set, last observation carried forward).