One of the criticisms that health professionals sometimes make of evidence-based research is that individual studies or reviews do not apply to the specific patient they are caring for. Of course, each patient is unique with their own values and preferences, as well as their own particular clinical characteristics, genetic make-up, biological markers and sociodemographic background. Finding research that exactly matches individual patients can be a tall order.

A potential solution to this problem is personalised medicine, an approach that involves customising the care given to a patient to better match their individual characteristics with a specific treatment. There has been a lot of interest in this approach from mental health researchers over recent years, particularly in relation to patients with depression (Simon et al).

A new systematic review published in the Depression and Anxiety journal investigates personalised treatment of adult depression by comparing different treatments:

• Antidepressants
• Psychotherapies
• Combined treatment (antidepressants and psychotherapies)

In different populations:

• Different sociodemographic groups (e.g. older adults, women, minority ethnic groups)
• Different types of depression (e.g. dysthymia, postnatal depression)
• With comorbid or somatic disorders (e.g. coronary heart disease, stroke)
• From a specific setting (e.g. outpatients, primary care)

The research team (led by Pim Cuijpers from VU University Amsterdam) searched for randomised controlled trials on the short-term or acute treatment of adult depression where:

• Antidepressants were directly compared to psychotherapies
• Antidepressants were directly compared to a combined treatment
• Psychotherapies were compared with a combined treatment

They found 52 studies (including a total of 4,734 patients) to include in their analysis, which covered 20 characteristics of depressed adults.

Here’s what they found:

• Antidepressants were significantly more effective than psychotherapy in patients with dysthymia (g = −0.28; 95% CI: −0.53∼0.04)
• There was no significant difference between antidepressants and psychotherapies in outpatients or patients from primary care, with chronic depression or with older adults
• Combined treatment was significantly more effective than antidepressants alone in outpatients (g = 0.54; 95% CI: 0.35∼0.74) and in older adults

The authors went on to make some interesting points about the quantity of research in this field. At first glance this seems to be well served area with so many trials included in this review, but it’s important to understand the breadth of the research and the number of different patient characteristics that are being studied. The authors conclude that 4 times as many trials are required before this review has sufficient statistical power to show an effect size of g = 0.5.

As is often the case, the researchers conclude by calling for further research in this area:

Although a considerable number of studies have compared medication, psychotherapy, and combined treatments, and some preliminary results are useful for deciding which treatment is best for which patient, the development of personalised treatment of depression has only just begun.

Links

Cuijpers P, Reynolds CF 3rd, Donker T, Li J, Andersson G, Beekman A. PERSONALIZED TREATMENT OF ADULT DEPRESSION: MEDICATION, PSYCHOTHERAPY, OR BOTH? A SYSTEMATIC REVIEW. Depress Anxiety. 2012 Jul 19. doi: 10.1002/da.21985. [Epub ahead of print] [PubMed abstract]

Simon GE, Perlis RH. Personalized medicine for depression: can we match patients with treatments? Am J Psychiatry. 2010 Dec;167(12):1445-55. Epub 2010 Sep 15.