Association between early-onset affective disorders and hypothyroidism in a larger number of psychiatric drug-free patients

AIMS We aimed to assess the association between early onset of affective disorders and hypothyroidism in a larger number of psychiatric drug-free patients with bipolar disorder (BD) or major depressive disorder (MDD). METHODS Early onset of affective disorders was defined as BD and MDD developed before the age of 22 years. The hypothyroidism hierarchy were diagnosed biochemically and included subclinical and overt hypothyroidism in this study. Demographic and clinical data including diagnosis, illness duration and thyroid function parameters (TSH, T4, FT4, T3 and FT3) at admission were collected from patients' records. Adjusted odds ratio (OR) and 95% confidence interval (CI), which were estimated by logistic regression model, were used to assess the association between early-onset affective disorder and hypothyroidism. RESULTS The prevalence of hypothyroidism in early-onset affective disorders was higher than that in late-onset patients (in BD, 9.4% vs. 6.2%, χ2 = 6.020, P = 0.014; and in MDD 12.7% vs. 6.6%, χ2 = 13.295, P