Advertisement

A Practical Biomarker for Selecting an Antidepressant?

Summary and Comment |
July 30, 2014

A Practical Biomarker for Selecting an Antidepressant?

  1. Joel Yager, MD

C-reactive protein levels might modestly help predict differential responses to escitalopram and nortriptyline in depressed patients.

  1. Joel Yager, MD

Inflammatory biomarkers are elevated in major depression and are associated with adverse outcomes; concurrently, serotonin and norepinephrine differentially affect inflammatory processes. These investigators asked whether baseline serum levels of the inflammatory biomarker C-reactive protein (CRP) predict differences in therapeutic response to various antidepressant classes. Previously associated with depression, CRP has a stable diurnal cycle, is not influenced by meals, and is commonly measured in routine medical practice.

The researchers analyzed a subset of data from a multisite treatment study on 241 depressed patients with baseline CRP values (mean age, 41; women, 63%; history of ≥2 depression episodes, 68%). Patients were randomized to 12 weeks of escitalopram (titrated to mean dose of 17 mg/day) or nortriptyline (titrated to mean dose of 106 mg/day); 74% completed the study.

Globally, the two treatments showed comparable efficacy. After adjustment for potential confounders, low CRP levels (<1 mg/L) were associated with modestly better outcomes with escitalopram than with nortriptyline. Moderate or higher levels (1–3 mg/L and >3 mg/L) were associated with modestly better outcomes with nortriptyline. Findings held in factor analyses of observed mood, cognitive, and neurovegetative dimensions. Overall, CRP levels accounted for about 10% of individual differences in outcomes.

Comment

Not ready for clinical application and in need of replication, these findings suggest that CRP levels are associated, for obscure reasons, with differential efficacy of escitalopram (a highly selective serotonin reuptake inhibitor) and nortriptyline (which preferentially blocks norepinephrine uptake, weakly affects serotonin transporters, and binds histaminic, muscarinic, and some serotonin receptors). Among the many remaining questions is whether other inflammatory biomarkers involved in humoral or cellular responses might add to our abilities to predict differential responses to specific antidepressants.

Editor Disclosures at Time of Publication

  • Disclosures for Joel Yager, MD at time of publication Grant /Research support AHRQ Editorial boards Bulletin of the Menninger Clinic; Eating Disorders: Journal of Treatment and Prevention; Eating Disorders Review (Editor-in-Chief); International Journal of Eating Disorders; UpToDate; FOCUS: The Journal of Lifelong Learning in Psychiatry Leadership positions in professional societies American Psychiatric Association (Chair, Council of Quality Care)

Citation(s):

Your Comment

(will not be published)

Filtered HTML

  • Allowed HTML tags: <a> <em> <strong> <cite> <blockquote> <code> <ul> <ol> <li> <dl> <dt> <dd>
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.

Plain text

  • No HTML tags allowed.
  • Web page addresses and e-mail addresses turn into links automatically.
  • Lines and paragraphs break automatically.
Do you have any conflict of interest to disclose?
CAPTCHA
This question is for testing whether you are a human visitor and to prevent automated spam submissions.
Image CAPTCHA
Enter the characters shown in the image.

Vertical Tabs

* Required

Reader comments are intended to encourage lively discussion of clinical topics with your peers in the medical community. We ask that you keep your remarks to a reasonable length, and we reserve the right to withhold publication of remarks that do not meet this standard.

PRIVACY: We will not use your email address, submitted for a comment, for any other purpose nor sell, rent, or share your e-mail address with any third parties. Please see our Privacy Policy.

Advertisement
Advertisement
Advertisement