Depression is the single largest cause of disability globally. Therefore, it is critical to find effective treatments. Current practice guidelines recommend anti-depressant medications and various psychotherapies as first-line treatments for depressive disorders. Although medications are easily accessible, questions remain about the impact of their long-term use, side effects, and patient’s preference for psychological therapies. Hence, it is essential to consider alternative treatments. Depression tends to be a recurrent disorder, but there is little research on the longer-term outcomes related to anti-depressant medication. Further, depressive experiences extend beyond symptoms and affects social, physical, and psychological functioning, yet most studies focus on symptom reduction. In this study, Cohen and colleagues assessed the relative outcomes of interpersonal psychotherapy (IPT) versus antidepressant medication. They also looked at relative long-term outcomes and results beyond symptom reduction. The authors did an individual patient data meta-analysis – that is, they meta-analyzed the original data from 9 of 15 randomized controlled trials that evaluated the relative efficacy of IPT and anti-depressant medications. Meta-analyses of individual patient data are less biased because they use the original data from a study rather than the aggregated effect sizes reported in publications. There was no significant difference in treatment effect between IPT and antidepressants on post-treatment depression, and the difference was minuscule (d = 0.088, 95% CI [.0.018 to 0.194], p = 0.103, k = 9, N = 1530). 49.5% of the participants in the IPT conditions and 55.2% in the antidepressant conditions responded to treatment (i.e., > 50% reduction of symptoms post-treatment). At follow-up, no significant differences between IPT and anti-depressant medications were found on depression symptoms again with tiny differences (d = 0.150, 95% CI .0.023 to 0.323], p = 0.088, k = 3, N = 716). There were no differences in social functioning, quality of life, coping, personality, interpersonal problems, anxiety, social functioning, and general psychopathology at follow-up.
There were no significant differences in any of the outcomes at post-treatment and follow-up between IPT and antidepressant medications. Although about 50% of patients “responded” (improved) post-treatment, the authors did not have enough data to evaluate the improvement rates at follow-up. The rates of non-response at follow-up from previous research were considerably higher. This study suggests that IPT is a viable alternative to anti-depressant medication for those patients with depression who do not respond to medications, cannot tolerate their side effects, or prefer to receive psychotherapy.
Cohen, Z.D., Breunese, J., Markowitz, J.C., Weitz, E.S., Hollon, S.D., Browne, D.T…. Driessen, E. (2024). Comparative efficacy of interpersonal psychotherapy and antidepressant medication for adult depression: A systematic review and individual participant data meta-analysis. Psychological Medicine, 54, 3785–3794. https://doi.org/10.1017/S0033291724001788.