Plasma cytokine profiles in depressed patients who fail to respond to selective serotonin reuptake inhibitor therapy

J Psychiatr Res. Apr-Jun 2007;41(3-4):326-31. doi: 10.1016/j.jpsychires.2006.05.013. Epub 2006 Jul 25.

Abstract

Objective: Approximately 30% of patients with depression fail to respond to a selective serotonin reuptake inhibitor (SSRI). Few studies have attempted to define these patients from a biological perspective. Studies suggest that overall patients with depression show increased production of proinflammatory cytokines. We examined pro- and anti-inflammatory cytokine levels in patients who were SSRI resistant.

Methods: Plasma concentrations of IL-6, IL-8, IL-10, TNF-alpha and sIL-6R were measured with enzyme linked immunosorbent assays (ELISA) in DSM-1V major depressives who were SSRI resistant, in formerly SSRI resistant patients currently euthymic and in healthy controls.

Results: Patients with SSRI-resistant depression had significantly higher production of the pro-inflammatory cytokines IL-6 (p=0.01) and TNF-alpha (p=0.004) compared to normal controls. Euthymic patients who were formerly SSRI resistant had proinflammatory cytokine levels which were similar to the healthy subject group. Anti-inflammatory cytokine levels did not differ across the 3 groups.

Conclusion: Suppression of proinflammatory cytokines does not occur in depressed patients who fail to respond to SSRIs and is necessary for clinical recovery.

Publication types

  • Clinical Trial
  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Analysis of Variance
  • Antidepressive Agents / therapeutic use*
  • Cytokines / blood*
  • Depressive Disorder, Major / blood*
  • Depressive Disorder, Major / drug therapy
  • Drug Resistance / physiology*
  • Enzyme-Linked Immunosorbent Assay / methods
  • Female
  • Humans
  • Male
  • Middle Aged
  • Psychiatric Status Rating Scales
  • Serotonin Uptake Inhibitors / therapeutic use*

Substances

  • Antidepressive Agents
  • Cytokines
  • Serotonin Uptake Inhibitors