%0 Journal Article
%T Dosage effects of psychodynamic and schema therapy in people with comorbid depression and personality disorder: four-arm pragmatic randomised controlled trial.
%A Kool M
%A Van H
%A Arntz A
%A Bartak A
%A Peen J
%A Dil L
%A de Boer K
%A Dekker J
%J Br J Psychiatry
%V 0
%N 0
%D 2024 Apr 11
%M 38602168
%F 10.671
%R 10.1192/bjp.2024.56
%X <B>BACKGROUND: </B>Higher intensity of psychotherapy might improve treatment outcome in depression, especially in those with comorbid personality disorder.<BR><B>OBJECTIVE: </B>To compare the effects of 25 individual sessions (weekly) of two forms of psychotherapy - short-term psychoanalytic supportive psychotherapy (SPSP) and schema therapy - with the same treatments given for 50 sessions (twice weekly) in people with depression and personality disorder. Trial registration: NTR5941.<BR><B>METHODS: </B>We conducted a pragmatic, double-randomised clinical trial and, over 37 months, recruited 246 adult out-patients with comorbid depression/dysthymia and personality disorder. A 2 × 2 factorial design randomised participants to 25 or 50 sessions of SPSP or schema therapy. The primary outcome was change in depression severity over 1 year on the Beck Depression Inventory II (BDI-II). Secondary outcomes were remission both of depression and personality disorder.<BR><B>RESULTS: </B>Compared with 25 sessions, participants who received 50 sessions showed a significantly greater decrease in depressive symptoms over time (time × session dosage, P < 0.001), with a mean difference of 5.6 BDI points after 1 year (d = -0.53, 95% CI -0.18 to 0.882, P = 0.003). Remission from depression was also greater in the 50-session group (74% v. 58%, P = 0.025), as was remission of personality disorder (74% v. 56%, P = 0.010).<BR><B>CONCLUSIONS: </B>Greater intensity of psychotherapy leads to better outcomes of both depression and personality status in people with comorbid depression and personality disorder.