Low Baseline Levels of Interest and Activity as Predictors of Antidepressant Response

There are no robust predictors to guide selection of initial or second-line antidepressant treatment for depressed individuals. In a two-phase, multisite, Canadian study, researchers enrolled 188 patients with unipolar major depression and treated them with open-label escitalopram for 8 weeks. Of 166 patients entering phase two, 90 without escitalopram response (≥50% improvement in symptoms) were treated openly with aripiprazole augmentation for another 8 weeks.

Interest and activity (concentration, energy, inability to feel, lassitude) were measured with both self- and observer-rating scales. Low levels of interest/activity at baseline predicted worse escitalopram response at week 8. In patients receiving aripiprazole augmentation, low base…