AUTHOR=Alvarado-Esquivel Cosme , Estrada-Martínez Sergio , Pérez-Alamos Alma Rosa 

TITLE=A Case–Control Seroprevalence Study on the Association Between Toxoplasma gondii Infection and Bipolar Disorder

JOURNAL=Frontiers in Psychiatry

VOLUME=10

YEAR=2019

URL=https://www.frontiersin.org/journals/psychiatry/articles/10.3389/fpsyt.2019.00766

DOI=10.3389/fpsyt.2019.00766

ISSN=1664-0640

ABSTRACT=<p><bold>Background and Aims:</bold> Infection with the parasite <italic>Toxoplasma gondii</italic> has been associated with bipolar disorder in several countries other than Mexico. Therefore, we sought to determine the association between seropositivity to <italic>T. gondii</italic> and bipolar disorder in a Mexican population.</p><p><bold>Methods:</bold> We performed an age- and gender-matched case–control study of 66 patients with bipolar disorder (WHO <italic>International Classification of Diseases, 10th Revision</italic> code: F31) and 396 subjects without this disorder from the general population. Anti-<italic>Toxoplasma</italic> immunoglobulin G (IgG) and IgM antibodies were determined using commercially available enzyme-linked immunoassays.</p><p><bold>Results:</bold> Six (9.1%) of the 66 patients with bipolar disorder and 22 (5.6%) of the 396 controls had anti–<italic>T. gondii</italic> IgG antibodies (odds ratio [OR] = 1.7; 95% confidence interval [CI] = 0.66–4.36; <italic>P</italic> = 0.26). Stratification by gender and age did not show a difference in seroprevalence between cases and controls. The frequency of high (&gt; 150 international units/ml) anti–<italic>T. gondii</italic> IgG levels was similar in cases (n = 2) and in controls (n = 12) (OR = 1.0; 95% CI = 0.21–4.57; <italic>P</italic> = 1.00). Stratification by <italic>International Classification of Diseases, 10th Revision</italic> F31 codes showed that patients with F31.3 code had a higher seroprevalence of <italic>T. gondii</italic> infection than their age- and gender-matched controls (OR = 16.4; 95% CI = 1.25–215.09; <italic>P</italic> = 0.04). None of the six anti–<italic>T. gondii</italic> IgG–seropositive patients with bipolar disorder and 4 (18.2%) of the 22 anti–<italic>T. gondii</italic> IgG–seropositive controls had anti–<italic>T. gondii</italic> IgM antibodies (<italic>P</italic> = 0.54).</p><p><bold>Conclusions:</bold> Our results suggest that <italic>T. gondii</italic> seropositivity is not associated with bipolar disorder in general. However, a specific type of bipolar disorder (F31.3) might be associated with <italic>T. gondii</italic> seropositivity. Further research to elucidate the role of <italic>T. gondii</italic> infection in bipolar disorder is needed.</p>