PPRNet Clinical summary: Long-Term Effects of Psychotherapies for Depression

Hundreds of randomized controlled trials have shown that CBT, IPT, behavioural activation, brief psychodynamic therapy (PDT) and other treatments have a significant and positive effect on depressive symptoms when compared to control conditions. Psychotherapies have also been found to be comparable to antidepressant medications in the short-term. It is unclear, however, what the effects are of psychotherapies in the longer term. The number of studies examining longer-term (1-year+) follow-ups is limited. Another issue is that current meta-analyses on longer-term effects focus on outcomes at specific time points post-randomization (6 months, or 1 year, or 18 months, etc.), rather than examining all time points simultaneously. This limits what the research can say about how treatments affect outcomes over time. In this study, Cuijpers and colleagues conducted a meta-analysis of randomized controlled trials evaluating the long-term outcomes of psychotherapies for adult depression compared with control conditions (waitlist, treatment as usual, placebo). Treatments included any theoretical orientation (CBT, IPT, PDT) delivered individually, in groups, by phone, or as guided self-help. They found 191 studies involving 33,691 patients. Half of all trials examined CBT, and 40.7% of studies provided treatment in an individual format. The mean number of sessions was 9.8 (SD = 5.7). Of the follow-up measurements, 9.7% occurred more than 12 months after randomization. Psychotherapies were more effective than controls, as indicated by standardized mean differences (SMDs). These effects were moderately large at 3 months post-randomization (SMD = 0.544; 95% CI: 0.47, 0.61) and declined to a small-to-moderate size by 1 year post-randomization (SMD = 0.389; 95% CI: 0.31, 0.47). The effects remained stable to 5 years post-randomization. The response rate (defined as 50% reduction in patients’ symptoms) was about 35% at 23 weeks post-randomization among those receiving psychotherapy, and about 24% at 32 weeks among those in the control conditions. Of the 191 studies, 40.3% were rated as having a high risk of bias, and only 18.3% had a low risk of bias, suggesting problems in the conduct of a majority of the trials. There were no differences between treatment orientations in long-term outcomes, except that behavioural activation had poorer outcomes than CBT.

Practice Implications 

The beneficial effects of time-limited psychotherapies for depression appear to be sustained in longer-term follow-up periods. This is consistent with research showing psychotherapies to be more effective than antidepressants in the longer term. However, the effects of psychotherapies remain modest, with about 35% of patients improving compared to about 24% in control conditions in the longer term. The research included in these meta-analyses is subject to a risk of bias that reduces our confidence in the findings. Other research in community-based settings suggests that longer-term treatments may be necessary to achieve good outcomes for a higher percentage of patients.

Cuijpers, P., Miguel, C., Kaya Aglio, E., van Straten, A., Karyotaki, E. and Harrer, M. (2026), Long-term effects of psychotherapies for depression: an advanced meta-analysis. World Psychiatry, 25: 287-294. https://doi.org/10.1002/wps.70065