Correlation of Suicidal Thoughts and Toxoplasmosis in Patients With Depression

Objective We investigated the correlation between serum anti-Toxplasma gondii IgG and suicidal thoughts in depressive patients. Methods Depressive patients with (n = 100) and without (n = 100) suicidal thoughts along with 100 healthy control subjects were recruited for this study. In all three groups, a semi-structured clinical interview form called Structured Clinical Interview for DSM-IV (Diagnostic and Statistical Manual of Mental Disorders) Axis-I Disorder (SCID-I), Hamilton Depression Rating Scale (HAMD), suicidal behavior scale, and a sociodemographic data form were completed. Sera from all participants were taken, and anti-toxoplasma IgG was measured by Enzyme Linked Immunosorbent Assay (ELISA)-Chemiluminescent Microparticle Immunoassay. Statistical analysis of the data was performed. Results The serum anti-toxoplasma IgG levels of patients with suicidal thoughts were significantly higher than those without suicidal thoughts and the controls, which were 80.04 ± 40.66, 78 ± 14.82, and 19.98 ± 14.65, respectively, p < 0.001. There was no correlation between toxoplasma IgG and HAMD score in patients lacking suicidal thoughts (r = -0.112, p = 0.463). Conclusion This study shows a correlation between seropositivity for anti-Toxoplasma gondii IgG and depression with suicidal thoughts.