Sudden gains and losses in the treatment of patients with anxiety, depressive and comorbid disorders

Theoretical background: Psychotherapy research has shown that the identification and prediction of individual continuous and discontinuous paths of change is of the greatest importance in understanding therapy progress and outcome. Objective: Thus, in this study the relationship between discontinuity (great discrepancies between two sessions, losses and gains) and patterns of change on the one hand and outcome on the other hand were analyzed. In addition, an extension of the underlying sudden gain concept, the so-called sudden loss, is introduced, which can be described as a great discrepancy between two consecutive sessions in a negative direction. Method: The outpatient population studied (N = 434) includes patients with depressive (n = 55) and anxiety (n = 115) symptoms as well as comorbid disorders (n = 225). Therapy courses were analyzed in respect of identifying sudden gains and losses and their relationship to patient status at the end of treatment. Results: Significant shifts were moderately prevalent, with 114 of 434 patients (26.27%) achieving a sudden gain or loss. Interestingly, patients who experience both gains and losses during the course of their treatment had significantly more sessions of therapy and also lower effect sizes in terms of their symptoms (e.g., in the BDI and BSI). Discussion: Results are discussed in terms of their implications for analyzing the course of treatment, the identification of negative courses in psychotherapy, as well as the evaluation of treatment progress.