Combined individual, group schema therapy effective for BPD

Combined individual and group schema therapy outperformed treatment as usual and predominantly group schema therapy for borderline personality disorder, according to results of a randomized clinical trial.

“Early trials of [schema therapy (ST)] demonstrated effectiveness when delivered in an individual format,” Arnoud Arntz, PhD, of the department of clinical psychology at the University of Amsterdam in the Netherlands, and colleagues wrote in JAMA Psychiatry. “A large effect was found for group ST delivered as an adjunct to TAU. “However, this group ST was delivered by its developers, and therefore, the generalizability of this finding to other therapists and other settings was unclear,” they added. “Also unknown was the extent to which group ST would be effective as a stand-alone treatment and the relative merits of combining individual and group ST.”

Arntz and colleagues sought to examine the effectiveness of ST delivered in a predominantly group (PGST) vs. combined individual and group format (IGST), as well as whether ST outperformed TAU for BPD. At 15 sites in five countries, they recruited outpatients aged 18 to 65 years with BPD between June 29, 2010, and May 18, 2016. Participants received either PGST (n = 125), IGST (n = 124) or optimal TAU (n = 246). Cohorts of 16 to 18 participants underwent random assignment in a 1:1 ratio to PGST vs. TAU or IGST vs. TAU, with both ST formats delivered over 2 years via two weekly sessions in year 1 followed by a gradual decrease in frequency during year 2. Change in BPD severity over time, assessed via the Borderline Personality Disorder Severity Index (BPDSI) total score served as the main outcome. As a secondary outcome, researchers assessed treatment retention using generalized linear mixed model survival analysis.

Results showed PGST and IGST combined outperformed TAU regarding reduced BPD severity (Cohen d = 0.73; 95% CI, 0.29-1.18). For this outcome, IGST outperformed TAU (Cohen d = 1.14; 95% CI, 0.57-1.71) and PGST (Cohen d = (0.84; 95% CI, 0.09-1.59); however, PGST was not significantly different from TAU (Cohen d = 0.3; 95% CI, 0.29 to 0.89). The IGST arm had greater treatment retention than the PGST and TAU arms, but the TAU and PGST arms did not significantly differ.

“Future research should focus on the direct comparison of individual and combined ST formats; the testing of less extreme combinations of group and individual ST; direct comparisons of ST with other evidence-based treatments, including the study of factors associated with better treatment allocation; and the testing of ST in countries in other regions of the world,” Arntz and colleagues wrote.