Further evidence of depressive symptomatology profile predicting treatment outcome.

Background: Non-response to treatment is a major problem in Major Depressive Disorder. The identification of predictors of poor outcome could improve treatment strategies. Overall baseline severity is one of the strongest predictors, but the specific symptoms profile is poorly investigated.

Methods: Baseline symptoms scores of 1533 depressed patients were assessed through the 30-item Inventory for Depressive Symptomatology, Clinician-rated (IDS-C₃₀), as part of the Sequenced treatment alternatives to relieve depression (STAR*D) trial. Treatment outcomes were assessed after treatment with citalopram. We tested IDS-C₃₀ individual items associated with non-response in the whole sample and sex-stratified subgroups.

Results: Sadness, sleep disturbances and lassitude were predictors of outcome in the whole sample. Females showed higher scores at many somatic domains (i.e., aches and pain), the latter relating to poor outcome. Anhedonic features, albeit with sex-specific differences, were associated with poor outcome across all study groups, along with depression severity and suicidal thoughts.

Conclusions: Our findings further refine the observation that specific baseline symptomatology profiles are related to poor response in depressed individuals. This finding may inform at a clinical level for personalised treatment. The sex-specific differences suggest a thorough assessment of depressive features at the very first approach with the depressed patient.

Keypoints: Sadness, sleep disturbances and reduced energy are strong predictors of poor outcome in depressed individualsSomatic complaints may be stronger predictors among females compared to malesAnhedonic features relate to non-response.