Measuring Changes in Depression and Assessing Optimal Treatment:
New Evidence Syntheses

Recently, investigators at the Durham VA Evidence-Based Practice Center conducted literature reviews to determine the optimal length of antidepressant medication, the value of psychotherapy as an augmentation or substitution for antidepressants, as well as the responsiveness of depression questionnaires for primary care patients with MDD.

Specifically, ESP investigators reviewed the literature published between 1950 and March 2, 2009 to answer the following key questions:

1. In patients with MDD treated in primary care settings, what assessment tools are responsive to change?
2. In primary care patients with MDD who remit with antidepressant medication, what is the minimum treatment duration to decrease the risk of relapse or recurrence?
3. In primary care patients with MDD who do not achieve remission with acute phase antidepressant treatment, is empirically-based psychotherapy effective when used as an augmentation or substitution treatment?

For Question 1, three observational studies were evaluated and results suggest that the Patient Health Questionnaire-9 (PHQ-9) — a brief depression questionnaire — is the best validated instrument for detecting clinically important response to treatment for depression.

For Question 2, four studies were evaluated, including three randomized controlled trials. Investigators found moderately strong evidence that continued antidepressant treatment decreases the risk of subsequent relapse for patients with MDD, who achieve partial- or full-remission. Continued treatment for 1 to 2 years after achieving remission decreased the risk of relapse by almost 50%.

For Question 3, five randomized clinical trials (total of 567 non-VA patients) which examined the effect of psychotherapy in patients who had shown resistance to antidepressant therapy were evaluated. Investigators concluded that current trials do not support favoring psychotherapy over antidepressant medication for mid-life adults with treatment resistant MDD; however, psychotherapy appears to be an equally effective treatment compared to antidepressant medication, and is therefore a reasonable treatment option for this demographic.

Conclusions

Brief depression questionnaires, such as the PHQ-9, could be used in VA for performance measurement. Studies evaluating responsiveness for the PHQ-9 in key subgroups (e.g., medical comorbidity, psychiatric comorbidity) could strengthen its validity. In addition, although continued antidepressant treatment beyond the acute phase decreases relapse, the optimal duration of treatment remains uncertain. Future studies might assess critical periods of increased relapse, if they exist, and measure the balance between adverse effects and beneficial effects, as patients stay on antidepressant vs. placebo treatment. While psychotherapy appears to be as effective as antidepressant medication, these results may not be applicable to the Veteran population. Thus, future research should evaluate the potential treatment benefit of psychotherapy for treatment resistant depression in Veterans.

Implications

VA's Patient Care Services (PCS), Office of Mental Health, and the Office of Quality and Performance (OQP) requested these ESP reports on the topic of depression and will use them as background to inform their decision-making.

Please feel free to forward this information to others!

Read past HSR&D Management e-Briefs on the HSR&D website.

This Management e-Brief is provided to inform you about recent HSR&D findings that may be of interest. The views expressed in this article are those of the authors and do not necessarily reflect the position or policy of the Department of Veterans Affairs. If you have any questions or comments about this Brief, please email CIDER. The Center for Information Dissemination and Education Resources (CIDER) is a VA HSR&D Resource Center charged with disseminating important HSR&D findings and information to policy makers, managers, clinicians, and researchers working to improve the health and care of Veterans.

This report is a product of the HSR&D Evidence-Based Synthesis Program (ESP), which was established to provide timely and accurate synthesis of targeted healthcare topics of particular importance to VA managers and policymakers - and to disseminate these reports throughout VA.

See the full reports online.