SUICIDAL IDEATION IS ASSOCIATED WITH ELEVATED INFLAMMATION IN PATIENTS WITH MAJOR DEPRESSIVE DISORDER
Article first published online: 15 MAR 2013
© 2013 Wiley Periodicals, Inc.
Depression and Anxiety
Volume 30, Issue 4, pages 307–314, April 2013
How to Cite
O'Donovan, A., Rush, G., Hoatam, G., Hughes, B. M., McCrohan, A., Kelleher, C., O'Farrelly, C. and Malone, K. M. (2013), SUICIDAL IDEATION IS ASSOCIATED WITH ELEVATED INFLAMMATION IN PATIENTS WITH MAJOR DEPRESSIVE DISORDER. Depress. Anxiety, 30: 307–314. doi: 10.1002/da.22087
- Issue published online: 10 APR 2013
- Article first published online: 15 MAR 2013
- Manuscript Accepted: 8 FEB 2013
- Manuscript Revised: 4 FEB 2013
- Manuscript Received: 2 OCT 2012
- Mental Health Research and Society in Science
- The Branco Weiss Fellowship
- Lundbeck Research Scholarship
- biological markers;
- mood disorders;
Patients with major depressive disorder (MDD) who attempt or complete suicide have elevated inflammation compared to nonsuicidal patients with MDD. However, greater severity of depression and the medical lethality of suicide attempts could account for such elevated inflammation in suicide attempters and suicide completers.
To clarify, we measured inflammatory markers in patients with MDD with and without high levels of suicidal ideation and in nondepressed controls (N = 124). Levels of suicidal ideation, depression severity, and recent suicide attempts were assessed by structured clinical interviews. A composite score including the inflammatory markers tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-10 (IL-10), and C-reactive protein (CRP) was used as an inflammatory index. Analysis of covariance models were used to assess group differences with adjustments for age and gender.
Patients with MDD and high suicidal ideation had significantly higher inflammatory index scores than both controls, F(1,53) = 18.08, partial η2 = .25, P < .001, and patients with MDD and lower suicidal ideation F(1,44) = 7.59, partial η2 = .15, P = .009. In contrast, patients with lower suicidal ideation were not significantly different from controls on the inflammatory index, F(1,63) = .52, partial η2 = .01, P = .47. Follow-up analyses indicated that differences between patients with MDD and high versus lower suicidal ideation were independent of depression severity and recent suicide attempts.
Suicidal ideation may be uniquely associated with inflammation in depressed patients.