Depression treatment: the evidence base from a primary care perspective

- Jennifer Middleton, MD, MPH

Most patients with depression receive treatment solely from a primary care physician. Family physicians have had to largely rely on studies and guidelines from psychiatric settings to make decisions about depression treatment, but a new systematic review, published in this month's Annals of Family Medicine, looks at this issue solely from a primary care perspective.

Linde et al performed a systematic review of treatments for depression, both both psychological and pharmacological, with one main stipulation - the participants "had to be recruited from a primary care setting." For clarity's sake, the authors divided their massive systematic review into 2 articles, one focusing on psychological treatments and one focusing on pharmacologic treatments.

In Effectiveness of Psychological Treatments for Depressive Disorders in Primary Care: Systematic Review and Meta-Analysis, the authors identified 30 studies that met inclusion criteria. There were several types of therapies in these studies: Cognitive Behavioral Therapy (CBT), "problem-solving" therapy, and/or "other face-to-face psychosocial therapies." The authors further grouped these studies by time spent between patient and therapist: face-to-face (at least 6 sessions), guided self-help (fewer than 6 face-to-face sessions), and no/minimal contact (less than 90 minutes of total face-to-face time). A handful of studies also investigated telephone counseling with either CBT or problem-solving therapy.

The authors found that all of these treatment modalities were more effective than usual care, though the effect size was greater for major depression diagnoses than for mild depression and/or dysthmia diagnoses. Interestingly, they also found that 6+ sessions of face-to-face counseling (regardless of the type of counseling) wasn't necessarily more effective than < 6 sessions and/or telephone counseling. For patients who find attending multiple counseling sessions burdensome, this meta-analysis shows that fewer sessions - or even telephone counseling - is just as effective.

In Effectiveness of Pharmacological Treatments for Depressive Disorders in Primary Care: Systematic Review and Meta-Analysis, the authors identified 66 studies that met inclusion criteria. Pharmacological treatments studied included multiple drug classes (TCAs, SSRIs, and several others). The authors found the most efficacy data for TCAs and SSRIs, though they found only "sparse" data on the "relative efficacy of anti-depressants" and could not make any determination regarding the superiority of any particular medications. They also found that TCAs are less acceptable to patients (higher rate of side effects leading to discontinuation) than SSRIs and the other newer classes of anti-depressants. The authors also commented that "there were no major differences in trials limited to patients with major depression and trials that included other depressive patients," which is helpful for family physicians who treat patients with less severe forms of depression.

Because this systematic review only included participants from a primary care setting, we can more comfortably generalize its findings to the patients we treat in our own offices. As family physicians, we need to be cautious about extrapolating too much from studies that focus on patients in a specialist's care population; by definition, these patients represent a narrower, often sicker population than the wider variety we see. This systematic review, sizable enough in scope to require 2 articles to fully describe its results, provides guidance for family physicians treating patients with mild to moderate depression as well as severe depression; it provides reassurance to patients unable to attend multiple psychotherapy sessions that even a few sessions can provide benefit. We need more studies like this one that report on participants from primary care settings.

There's an AFP By Topic on Depression and Bipolar Disorder if you'd like to read more; the collection contains articles about screening and diagnosis as well as treatment, and also has some helpful patient education materials.

Will this systematic review change the way you care for patients with depression?