Toxoplasma gondii infection and common mental disorders in the Finnish general population

Abstract

Objective We investigated whether T. gondii seropositivity is associated with 12-month depressive, anxiety and alcohol use disorders and current depressive symptoms and whether inflammation, measured by C-reactive protein (CRP) level, explains these associations. Method Health 2000 study (BRIF8901), conducted in years 2000–2001, is based on a nationally representative sample of Finns aged 30 and above, with 7112 participants and 88.6% response rate. DSM-IV depressive, anxiety and alcohol use disorders were assessed with the Composite International Diagnostic Interview and depressive symptoms with the Beck Depressive Inventory (BDI-21). We used logistic regression to investigate the association of T. gondii seropositivity with mental disorders and linear regression with BDI-21 scores. Results T. gondii seroprevalence was significantly associated with 12-month generalized anxiety disorder but not with other anxiety, depressive or alcohol use disorders. T. gondii seropositivity was associated with higher BDI-21 scores (beta 0.56, 95% CI 0.12–1.00, P=0.013) and with having a comorbid depressive and anxiety disorder (OR 1.86, 95% CI 1.16–2.97, P=0.010). Higher CRP levels were associated with these outcomes and with T. gondii seropositivity, but adjusting for CRP did not change the effect of T. gondii seropositivity. Limitations cross-sectional study design with no information on the timing of T. gondii infection. Conclusion T. gondii seropositivity is associated with generalized anxiety disorder, depressive symptoms and comorbid depressive and anxiety disorders, which is not mediated by inflammation.

Latent toxoplasmosis and psychiatric symptoms – A role of tryptophan metabolism?

“…Regarding the potential relationship between TOX and depression, previous studies have found varying results. Suvisaari et al (2017) found that TOX IgG titer levels correlated positively with depression scores, Flegr & Escudero (2016) found that TOX positivety was associated with depression in male but not female subjects whereas Pearce et al (2012) did not find any association between unipolar depression and TOX infection. Moreover, a recent meta-analysis concluded that no relationship between TOX and depression existed (Sutterland et al, 2015).…”

Exposure to common infections and risk of suicide and self-harm: a longitudinal general population study

“…Toxoplasma gondii is an intracellular parasite, most commonly spread by food or water that is contaminated with oocysts shed by cats, or by eating meat-containing tissue cysts, whereas the herpes viruses spread mostly through bodily fluids, and are among the most common viruses in humans. In recent studies of the general population in Finland, the seropositivity prevalence in adults was 20% for T. gondii [1], 72% for HSV-1 [2], 84% for CMV, and 98% for EBV [3]. Associations between these infections and mental health have been repeatedly found.…”

“…Toxoplasma may be associated with several mental disorders [4][5][6][7]. We have previously published cross-sectional results on the association between IgG antibodies against T. gondii and anxiety disorders and depressive and psychotic-like symptoms [1,8]. Furthermore, CMV has been linked to psychiatric disorders [9][10][11][12].…”

LatentToxoplasma gondiiinfection increases soluble mutant huntingtin and promotes neurodegeneration in the YAC128 mouse model of Huntington’s disease

“…T. gondii seropositivity is associated with increased risk of psychiatric disorders including schizophrenia and depression [58--60], but the nature of this relationship is debated [13,18]. The current findings, and an earlier study [39], show that HD mice respond differently to infection with the moderately pathogenic ME49 strain of T. gondii, as compared with control mice.…”