Cognitive Behavioral Psychotherapy as an Add-on in Comprehensive Outpatient Care of Non-affective Psychoses: A Multicenter Randomized-Controlled Effectiveness Trial in a Naturalistic Setting

Abstract

Background and hypothesis: Non-affective psychoses (NAP) are associated with severe consequences with regard to social functioning, physical health, employment, and suicidality. Treatment guidelines recommend cognitive behavioral therapy for psychosis (CBTp) as an effective additional treatment strategy to psychopharmacology. We hypothesized that outpatient CBTp has an add-on effect in individuals with NAP who already receive comprehensive outpatient care (COC) in Germany.

Study design: In a randomized-controlled effectiveness trial, 6 months of COC + CBTp were compared to COC. The primary outcomes were change of symptom severity as assessed by the Positive and Negative Symptom Scale (pre-/post-treatment and 6-month follow-up). Mixed linear models and effect sizes were used to compare changes across treatment groups. Additionally, the number of readmissions was compared.

Study results: N = 130 individuals with chronic NAP were recruited (COC + CBTp: n = 64, COC: n = 66). COC + CBTp participants significantly improved more regarding positive symptom severity (estimated mean difference at follow-up: -2.33, 95% CI: -4.04 to -0.61, P = .0083, d = 0.32) and general psychopathology (estimated mean difference at follow-up: -4.55, 95% CI: -7.30 to -1.81, P = .0013, d = 0.44) than the COC group. In both groups, negative symptom severity did not change significantly over time nor did groups differ regarding readmissions.

Conclusion: The results underline an add-on benefit of CBTp in chronically ill individuals with NAP. Superiority of CBTp was demonstrated in comparison with high-quality comprehensive care and may also be true in different comprehensive care settings.

Clinical trials registration: DRKS00015627.

Keywords: RCT; clinical trial; schizophrenia; treatment effects.

Fig. 1.

Patient flow. CBTp = cognitive behavioral therapy for psychosis, COC = comprehensive outpatient care.

Fig. 2.

Boxplots of the primary outcome of PANSS-scores for positive (A) and negative (B) symptoms as well as general psychopathology (C) for each time point and treatment arm. CBTp = cognitive behavioral therapy for psychosis; COC = comprehensive outpatient care; PANSS = Positive and Negative Syndrome Scale. *P ≤ .05, ****P ≤ .0001 (Tukey-corrected).