Elevated serum levels of homocysteine as an early prognostic factor of psychiatric disorders in children and adolescents.

Background and Goal. The aim was to examine the serum levels of homocysteine (Hcy) and their associations with the methylenetetrahydrofolate reductase (MTHFR) gene C677T polymorphism in patients with schizophrenia and mood disorders as well as controls. Materials and Methods. There were 198 patients: 82 with schizophrenia spectrum disorders, 22 with mood disorders, and 94 controls. The level of Hcy was determined by an isocratic high-performance liquid chromatography system. MTHFR C677T polymorphism was analysed using the restriction fragment length polymorphism-polymerase chain reaction method. Results. The average level of Hcy was 11.94 ± 5.6 μmol/L for patients with schizophrenia, 11.65 ± 3.3 μmol/L for patients with affective disorders, versus 6.80 ± 2.93 μmol/L in a control. The highest level of Hcy has been observed in patients with episodic-recurrent course of schizophrenia (11.30 ± 7.74 μmol/L), paranoid schizophrenia continuous (12.76 ± 5.25 μmol/L), and in patients with affective disorders (11.65 ± 3.26 μmol/L). An association between the MTHFR gene C677T polymorphism and Hcy level was found by linear regression analysis (r = 1.41, P = 0.029). Conclusions. The data indicate a link between Hcy levels and schizophrenia and mood disorders. No associations between the level of Hcy in patients with schizophrenia and mood disorders and the MTHFR C677T polymorphism were found.