Blog

May 2013

• Combining Medication and Psychotherapy in the Treatment of Depression

  Handbook of Psychotherapy and Behavior Change: Starting in March 2013 I will review one chapter a month the Handbook of Psychotherapy and Behavior Change in addition to reviewing psychotherapy research articles. Book chapters have more restrictive copy right rules than journal articles, so I will not provide author email addresses for these chapters. If you are interested, the Handbook table of content can be viewed on Amazon.

  Forand, N.R., DeRubeis, R.J., & Amsterdam, J.D. (2013). Combining medication and psychotherapy in the treatment of major mental disorders. In M.J. Lambert (Ed.) Bergin and Garfield’s handbook of psychotherapy and behaviour change (6^th ed.), pp. 735-774. Hoboken, N.J.: Wiley.

  This comprehensive chapter covers evidence for combining medication and psychotherapy for several disorders. This month I report on the section of the chapter on depression. Psychotherapy and antidepressant medications appear to have similar efficacy in short-term treatment trials, though psychotherapy has better outcomes than medication in the longer term. Psychotherapeutic treatments including Brief Dynamic Therapy (BDT), Interpersonal Psychotherapy (IPT), and Cognitive Behavioral Therapy (CBT) confer enduring benefit by preventing relapse and recurrence when compared to discontinuing medication. Antidepressant medication is modestly effective during initial short-term treatments with remission rates less than 50% and long term recurrence range from 40% to 85%. Combining medication with psychotherapy provides a small to moderate short term advantage over monotherapy of medication or psychotherapy. Combining medication and psychotherapy is more useful for when considering chronicity rather than severity of depression. The results are consistent for BDT, IPT, and for CBT.  In the longer term, efficacy of combined treatments is not better than either monotherapy. Taken together, the evidence for combined therapy for depression is modestly positive with little evidence that treatments interfere with each other (by contrast, see the March 2013 blog for findings of interference in combined therapy for anxiety disorders). Nevertheless, prolonged continuation of medication monotherapy is an added expense that is often ineffective. In fact, prolonged antidepressant medication maintenance can worsen the course of depressive illness for some, and efficacy tends to fade after 3 to 6 months of maintenance. Finally, there is emerging evidence of progressive tolerance (tachyphylaxis) or even worsening of symptoms during medication maintenance. Studies suggest that psychotherapy added to maintenance medication was associated with decreased relapse rates when compared to medication alone in the longer term.

  Practice implications

  Combined treatments (antidepressant medication plus psychotherapy) for major depression provide modest incremental improvements in response over monotherapy. Results of combination treatments are better, though still modest, for those with chronic depression. The evidence does not support the use of combined treatments for mild to moderate depression, unless the individual does not responds to initial monotherapy. Practitioners could consider monotherapy (i.e., psychotherapy or medication) first, followed by switching therapy or augmenting therapy for non-responders. If a patient is started on short term monotherapy of medication, practitioners may consider switching to psychotherapy for better long term relapse prevention.

• Are the Effects of Psychotherapy for Depression Overestimated?

  Niemeyer, H., Musch, J., & Pietrowsky, R. (2013). Publication bias in meta-analyses of the efficacy of psychotherapeutic interventions for depression. Journal of Consulting and Clinical Psychology, 81, 58-74.

  Meta-analyses are important ways of summarizing effects of medical and psychological interventions by aggregating effect sizes across a large number of studies. (Don’t stop reading, I promise this won’t get too statistical). The aggregated effect size from a meta analysis is more reliable than the findings of any individual study. That is why practice guidelines almost exclusively rely on meta analyses when making practice recommendations (see for example the Resources tab on this web site). However meta analyses are only as good as the data (i.e., studies) that go into them (hence, the old adage: “garbage in, garbage out”). For example, if the studies included in a meta analysis are a biased representation of all studies, then the meta analysis results will be unreliable leading to misleading practice guidelines. One problem that leads to unreliable meta analyses is called publication bias. Publication bias often refers to the tendency of peer reviewed journals not to publish studies with non-significant results (e.g., a study showing a treatment is no better than a control condition). Publication bias may also refer to active suppression of data by researchers or industry. Suppression of research results may occur because an intervention’s effects were not supported by the data, or the intervention was harmful to some study participants. In medical research, publication bias can have dire public health consequences (see this TED Talk). There is lots of evidence that publication bias has lead to a significant over-estimation of the effects of antidepressant medications (see Turner et al (2008) New England Journal of Medicine). Does publication bias exist in psychotherapy research, and if so does this mean that psychotherapy is not as effective as we think? A recent study by Niemeyer and colleagues (2013) addressed this question with the most up to date research and statistical techniques. They collected 31 data sets each of which included 6 or more studies of psychotherapeutic interventions (including published and unpublished studies) for depression. The majority of interventions tested were cognitive behavioral therapy, but interpersonal psychotherapy, and brief psychodynamic therapy were also included. The authors applied sophisticated statistical techniques to assess if publication bias existed. (Briefly, there are ways of assessing if the distribution of effect sizes across data sets fall in a predictable pattern called a “funnel plot” – specific significant deviations from this pattern indicate positive or negative publication bias). Niemeyer and colleagues found minimal evidence of publication bias in published research of psychotherapy for depression. This minimal bias had almost no impact on the size of the effect of psychotherapy for depression.

  Practice Implications

  This is a very important result indicating that despite a minor tendency toward a selective publication of positive results, the efficacy of all reviewed psychotherapy interventions for depression remained substantial, even after correcting for the publication bias. Niemeyer and colleagues’ findings demonstrate that publication bias alone cannot explain the considerable efficacy of psychotherapy for depression. Psychotherapeutic interventions can still be considered efficacious and recommended for the treatment of depression.

  Author email address: helen.niemeyer@hhu.de