Prediction of treatment response in unipolar depression: results from the German Algorithm Project (GAP 3)

Despite the continuing improvement of treatment options for depressive disorders, many patients do not achieve remission. This study will address the question, which clinical and sociodemographic variables are related to treatment outcome at discharge and at 1-year-follow up. Data were collected on 429 inpatients with the diagnosis of Major Depressive Disorder from the German Algorithm Project, phase 3 (GAP3). GAP3, a randomized controlled multicenter trial, compared two different treatment algorithms (Standardized Stepwise Drug Treatment Regimen, SSTR, and Computerized Decision and Expert System, CDES) with treatment as usual (TAU). Of 318 patients who were assessed at discharge, 77% were remitted. Demographic variables, like age, family status, education, occupation did not show any influence on treatment outcome at discharge or follow up. Severity of depression, a longer duration of the current episode, psychiatric comorbidity, personality disorder and anxious depression are however risk factors for not achieving remission at discharge. In contrast, patients being treated according to SSTR have a higher probability of being remitted compared to CDES- or TAU-patients. Being remitted at discharge increases the chance of being remitted at follow up, while psychiatric comorbidity reduces the probability of remission at follow up. We will further analyze the influence of process parameters (treatment characteristics, like duration of treatment) on treatment outcome.

This study was supported by Eli Lilly & Company, Janssen-Cilag, Pfizer Inc., Pharmacia, and WyethAyerst Laboratories, Inc