Toxoplasmosis, but not borreliosis, is associated with psychiatric disorders and symptoms
Schizophrenia Research 2018; 197: 603-604
Toxoplasmosis, but not borreliosis, is associated with psychiatric disorders and symptoms MENTAL
Flegr, J., Horáček, J.
Schizophrenia Research 2018; 197: 603-604
The association of infectious agents and schizophrenia
Krause, D., Matz, J., Weidinger, E., Wagner, J., Wildenauer, A., Obermeier, M., Riedel, M., Muller, N.
World Journal of Biological Psychiatry 2010; 11: 739-743
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Objectives. The influence of infectious agents on the pathogenesis of psychiatric disorders has been discussed for decades. Pre- and postnatal infections are risk factors for schizophrenia. This may be explained by chronic infections or an altered immune status. However most of the studies have only focused on one single pathogen and not on the impact of different infectious agents. We investigated the association between schizophrenia and various neurotophic infectious agents. Methods. A total of 31 schizophrenic patients and 30 healthy matched individuals were included. Antibody titres of cytomegalovirus, herpes simplex virus, Epstein-Barr virus, mycoplasma, chlamydia and toxoplasma were evaluated. For statistical analysis we used Fisher's exact and Wilcoxon test. Results. Significantly elevated positive antibody titres within schizophrenic patients were found only for Chlamydia trachomatis (P=0.005) and a trend to significance for herpes simplex virus (P=0.055). Combining the different agents, schizophrenics had a significantly higher rate of positive titres to infectious agents as compared to controls (P=0.04). Conclusions. The higher prevalence of antibodies within schizophrenic patients emphasizes a possible role of infectious agents in the pathogenesis of schizophrenia. Our data indicates that not one specific agent might be responsible for schizophrenic symptoms but the resulting immune response in the central nervous system.
Relation of Schizophrenia Prevalence to Latitude, Climate, Fish Consumption, Infant Mortality, and Skin Color: A Role for Prenatal Vitamin D Deficiency and Infections?
Kinney, D. K., Teixeira, P., Hsu, D., Napoleon, S. C., Crowley, D. J., Miller, A., Hyman, W., Huang, E.
Schizophrenia Bulletin 2009; 35: 582-595
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Previous surveys found a large (> 10-fold) variation in schizophrenia prevalence at different geographic sites and a tendency for prevalence to increase with latitude. We conducted meta-analyses of prevalence studies to investigate whether these findings pointed to underlying etiologic factors in schizophrenia or were the result of methodological artifacts or the confounding of sites' latitude with level of healthcare at those sites. We found that these patterns were still present after controlling for an index of healthcare-025EFinfant mortality-025EFand focusing on 49 studies that used similar diagnostic and ascertainment methods. The tendencies for schizophrenia prevalence to increase with both latitude and colder climate were still large and significant and present on several continents. The increase in prevalence with latitude was greater for groups with low fish consumption, darker skin, and higher infant mortality-025EFconsistent with a role of prenatal vitamin D deficiency in schizophrenia. Previous research indicates that poor prenatal healthcare and nutrition increase risk for schizophrenia within the same region. These adverse conditions are more prevalent in developing countries concentrated near the equator, but schizophrenia prevalence is lowest at sites near the equator. This suggests that schizophrenia-producing environmental factors associated with higher latitude may be so powerful they overwhelm protective effects of better healthcare in industrialized countries. The observed patterns of correlations of risk factors with prevalence are consistent with an etiologic role for prenatal vitamin D deficiency and exposure to certain infectious diseases. Research to elucidate environmental factors that underlie variations in schizophrenia prevalence deserves high priority.
Maternal exposure to toxoplasmosis and risk of schizophrenia in adult offspring
Brown, A. S., Schaefer, C. A., Quesenberry, C. P., Liu, L. Y., Babulas, V. P., Susser, E. S.
American Journal of Psychiatry 2005; 162: 767-773
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Objective: The authors examined the relationship between maternal antibody to toxoplasmosis and the risk of schizophrenia and other schizophrenia spectrum disorders in offspring. Toxoplasmosis is known to adversely affect fetal brain development.
Method: In a nested case-control design of a large birth cohort born between 1959 and 1967, the authors conducted serological assays for Toxoplasma antibody on maternal serum specimens from pregnancies giving rise to 63 cases of schizophrenia and other schizophrenia spectrum disorders and 123 matched comparison subjects. Toxoplasma immunoglobulin (Ig) G antibody was quantified by using the Sabin-Feldman dye test. The Ig titers were classified into three groups: negative (< 1: 16) reference), moderate ( 1: 16 - 1: 64), and high (>= 1: 128).
Results: The adjusted odds ratio of schizophrenia/schizophrenia spectrum disorders for subjects with high maternal Toxoplasma IgG antibody titers was 2.61 ( 95% confidence interval = 1.00 - 6.82). There was no association between moderate Toxoplasma Ig antibody titers and the risk of schizophrenia/spectrum disorders.
Conclusions: These findings suggest that maternal exposure to toxoplasmosis may be a risk factor for schizophrenia. The findings may be explained by reactivated infection or an effect of the antibody on the developing fetus. Given that toxoplasmosis is a preventable infection, the findings, if replicated, may have implications for reducing the incidence of schizophrenia.