Seroprevalence of Toxoplasma gondii infection among patients with psychiatric and neurologic disorders in Türkiye: a systematic review and meta-analysis.

BACKGROUND

Toxoplasma gondii (T. gondii) is a globally prevalent intracellular parasite capable of causing latent infections in humans. T. gondii, a widely prevalent protozoan parasite, has been increasingly linked to mental, psychiatric, and neurological disorders. Understanding its seroprevalence is critical to assess its potential public health impact and guide preventive strategies. Despite the extensive research conducted in Türkiye on this association, the outcomes have shown variability. A comprehensive synthesis is required to elucidate the seroprevalence of T. gondii among affected patient groups and to enhance our understanding of the potential public health implications. This study posits that the prevalence of T. gondii among patients with psychiatric and neurological disorders in Türkiye is substantial, with notable socioeconomic and geographical variations. It aims to estimate the seroprevalence of T. gondii infection among these patients in Turkey, adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

METHODS

A systematic review and meta-analysis were performed following the guidelines of the PRISMA. In November 2024, comprehensive searches were conducted across PubMed, Web of Science, Scopus, and the TR index using a set of predetermined keywords without imposing any temporal limitations. The methodological quality of the studies included in the review was evaluated using the Joanna Briggs Institute's Critical Appraisal Checklist, which is applicable to both randomized controlled trials and cross-sectional studies. Data were synthesized using a meta-analytic technique.

RESULTS

Prevalence was calculated using a random-effects model with a 95% confidence interval (CI). Cochran's Q and I2 statistics were performed to assess heterogeneity among the included studies, while funnel plots and Egger's tests were used to evaluate publication bias. The prevalence of toxoplasmosis was 34% (95% CI: 28%-39%). When the patient groups of the studies included in the research were classified, the subgroup analysis performed with the obtained data was found to be 34% (95% CI: 28%-39%) in patients with both neurological and psychiatric disorders.

CONCLUSION

This meta-analysis identified a significant seroprevalence of T. gondii infection among individuals with psychiatric and neurological disorders in Türkiye. These findings indicate a potential association between T. gondii exposure and neuropsychiatric conditions, highlighting the need for further research and increased clinical awareness in at-risk populations.