Concentrations of Thyroid Axis Hormones in Psychotic Patients on Hospital Admission: the Effects of Prior Drug Use

The aim of this study was to determine the concentrations of thyroid axis hormones in psychotic patients on hospital admission and to search for the associations between the concentrations of these hormones and prior drug use as well as mental symptoms.
Material and Methods. Psychiatric diagnoses, psychotropic drug use, and the severity of psychoses were evaluated using the standard methods on admission. Venous blood from patients and healthy controls was drawn for the analysis of free thyroxin (FT4), free triiodothyronine (FT3), thyroid-stimulating hormone (TSH), and sex hormone-binding globulin (SHBG) concentrations.
Results. Eighty-one psychotic patients, free of a thyroid disorder, were enrolled into the study. Compared with the controls, they displayed the higher FT4 concentrations in the general group (P=0.003) and the higher SHBG concentrations only in men (P=0.013). The FT4 concentration was higher in the patients who were not taking an antipsychotic drug on admission (P=0.039). No significant correlation was found between the severity of psychosis and concentrations of thyroid axis hormones. However, the FT3 concentration in the general group and TSH concentration in women correlated with the factor of the Brief Psychiatric Rating Scale expressing elevated mood.
Conclusions. Our study confirms the higher FT4 concentrations in a significant proportion of acute psychotic patients. The concentrations of thyroid axis hormones were found to be associated with prior antipsychotic treatment on hospital admission.