Clinical correlates of difficult-to-treat depression: Exploring an integrated day-care model of treatment.

Background and Aims: This study aimed to test the effectiveness of an individualized, integrated, day-care treatment programme for the acute phase of "difficult-to-treat depression" (DTD) in a sample of bipolar and unipolar subjects with a complex co-morbidity pattern.
Methods: A total of 291 patients meeting criteria for DTD were consecutively recruited. All participants underwent a 12-week day-care intervention including individual psychological support and group psycho-education. Subjects were assessed for depressive symptom severity by the 21-item Hamilton Depression Rating Scale (HDRS) at the baseline (T0) and after 4 (T1) and 12 (T2) weeks of treatment. A repeated measures general linear model was performed to test for interactive effects among variables.
Results: An overall significant improvement was detected in the majority of cases (F = 138.6, p < 0.0001). Responders reported lower rates of personality disorders and higher baseline depressive severity. An interaction between bipolarity and co-morbidity was associated with a poorer outcome (F = 5.9, p = 0.0034). Family involvement was the only significant predictor for symptom improvement (F = 7.9, adjusted p = 0.0025).
Conclusions: Our intervention proved to be effective in the treatment of complex and severe forms of depression. Our results on the role of family support require further investigation to better define suitable targets for tailored therapeutic approaches.