Associations of mental disorders and neurotropic parasitic diseases: a meta-analysis in developing and emerging countries.
Abstract Background Although they are declining worldwide, neurotropic parasitic diseases are still common in developing and emerging countries. The aim of this study was to estimate the pooled prevalence and pooled association measures of comorbidities between mental disorders (anxiety, depression, bipolar disorder, and schizophrenia) and neurotropic parasitic diseases (malaria, cysticercosis, toxoplasmosis, human African trypanosomiasis, Chagas disease, and human toxocariasis) in developing and emerging countries.Methods As the first meta-analysis on this topic, this study was performed in accordance with PRISMA guidelines. The protocol was registered in PROSPERO (N°CRD42017056521). The Medline, Embase, Lilacs, and Institute of Epidemiology and Tropical Neurology databases were used to search for articles without any restriction in language or date. We evaluated the quality of studies independently by two investigators using the Downs and Black assessment grid and pooled estimates using the random-effects method from CMA (Comprehensive Meta Analysis) Version 3.0.Results In total, 18 studies studies published between 1997 and 2016 met our inclusion criteria. We found that the prevalence of anxiety and depression in people suffering from Chagas disease and/or neurocysticercosis was 44.9% (95% CI, 34.4 – 55.9). In 16 pooled studies that included 1,782 people with mental disorders and 1,776 controls, mental disorders (schizophrenia and/or bipolar disorders) were associated with increased risk of toxoplasmosis and/or toxocariasis (odds ratio = 2.3; 95% CI, 1.7 – 3.2). Finally, schizophrenia was associated with an increased risk of the onset of toxocariasis and/or toxoplasmosis (odds ratio = 2.4 / 95% CI, 1.7 – 3.4).Conclusion Our pooled estimates show that the association between neurotropic parasitic diseases among people with related mental disorders, and mental disorders among people with neurotropic parasitic diseases are relatively high in developing and emerging countries even though most studies have been found in Asia. This meta-analysis could prove useful to researchers who want to further explore and understand the associations between mental disorders and neurotropic patristic diseases in developing and emerging countries.