Thyroid dysfunction in major psychiatric disorders in a hospital based sample

BACKGROUND & OBJECTIVES Abnormalities in thyroid hormonal status is common in major psychiatric disorders. Although the relevance of thyroid dysfunction to bipolar disorder is well-recognized, yet the association between thyroid dysfunction and schizophrenia-spectrum disorders is under-emphasized. The aim of this study was to examine and compare the rates of abnormal thyroid hormonal status in patients with schizophrenia-spectrum disorders and mood disorders in an inpatient tertiary care general hospital psychiatry unit. METHODS This was a retrospective hospital-based study on 468 inpatient samples. Data on serum thyroid stimulating hormone (TSH), T3 (triiodothyroxine), T4 (L-thyroxine), free unbound fractions of T3 and T4 (FT3 and FT4) were obtained from records of 343 patients, 18 patients were anti-TPO (anti thyroid peroxidase antibody) positive. The rates of abnormal thyroid hormonal status were compared using the chi square test. RESULTS Abnormal thyroid hormonal status in general, and presence of hypothyroidism and hyperthyroidism, in particular were seen in 29.3, 25.17 and 4.08 per cent patients with schizophrenia spectrum disorders, respectively. These were comparable to the rates in patients with mood disorders (23.24, 21.62 and 1.62%, respectively). Eleven of the 18 patients with antiTPO positivity had a schizophrenia-spectrum disorder. There were no gender differences. INTERPRETATION & CONCLUSIONS Thyroid dysfunction was present in patients with schizophrenia-spectrum disorder as well as mood disorders. Autoimmune thyroid disease was more commonly seen in patients with schizophrenia-spectrum disorders compared to mood disorders. The findings reiterate the relevance of screening patients with schizophrenia-spectrum disorders for abnormal thyroid hormonal status.