The Relationship Between Toxoplasma gondii Infection and Mood Disorders in the Third National Health and Nutrition Survey

Biol Psychiatry. 2012 Feb 9. [Epub ahead of print]

The Relationship Between Toxoplasma gondii Infection and Mood Disorders in the Third National Health and Nutrition Survey.

Pearce BD, Kruszon-Moran D, Jones JL.

Source
Department of Epidemiology, Emory University, Atlanta, Georgia.

Abstract
BACKGROUND:
Toxoplasma gondii (T. gondii) is a neurotropic protozoan parasite that causes persistent infection in humans. A substantial literature suggests that schizophrenia is associated with increased seroprevalence of T. gondii, but a possible link of the parasite with mood disorders has not been as thoroughly investigated.

METHODS:
We examined the association of Toxoplasma-specific immunoglobulin G results with mood disorder outcomes in 7440 respondents from the third National Health and Nutrition Survey, which is a nationally representative sample of the United States noninstitutionalized civilian population. Regression models were adjusted for numerous potential confounders, including tobacco smoking and C-reactive protein levels.

RESULTS:
No statistically significant associations were found between T. gondii seroprevalence and a history of major depression (n = 574; adjusted odds ratio [OR]: .8; 95% confidence interval [CI]: .5-1.2), severe major depression (n = 515; adjusted OR: .8; 95% CI: .6-1.2), dysthymia (n = 548; adjusted OR: 1.1; 95% CI: .7-1.8), or dysthymia with comorbid major depression (n = 242, adjusted OR: 1.2; 95% CI: .6-2.4), all p values were > .05, including analysis stratified by gender. However, there was a significant relationship between T. gondii seroprevalence and bipolar disorder type I for respondents in which both manic and major depression symptoms were reported (n = 41; adjusted OR: 2.4; 95% CI: 1.2-4.8; p < .05).

CONCLUSIONS:
In a population-based sample, T. gondii seroprevalence is not elevated in unipolar mood disorders but is higher in a subset of respondents with a history of bipolar disorder type 1.

Copyright © 2012 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

PMID: 22325983 [PubMed - as supplied by publisher]