Backgrounds: Autoimmune thyroiditis (AIT) is closely associated with major depressive disorder (MDD). However, its association with suicide attempts (SA) in this population remains unexplored. The study aimed to assess the prevalence and correlates of SA in first-episode drug-naïve (FEDN) MDD patients with AIT.
Methods: We recruited 1718 FEDN MDD outpatients and assessed depressive, anxiety, and psychotic symptoms by the Hamilton Rating Scale for Depression (HAMD), the Hamilton Rating Scale for Anxiety, and the Positive and Negative Syndrome Subscale positive subscale, respectively. The serum levels of free triiodothyronine, free thyroxine, thyroid stimulating hormone (TSH), anti-thyroglobulin, thyroid peroxidases antibody (TPOAb), and several other metabolic parameters were assessed. Multiple logistic regression model was applied to identify the correlates of SA in AIT MDD patients. The Area Under the Curve (AUC) was used to test the performance of this model.
Results: The prevalence of SA was higher in AIT patients than in non-AIT patients (34% vs 14%, p<0.001). The presence of AIT independently doubled the risk of SA (OR, 1.88, 95%CI, 1.42-2.50, p<0.001). Anxiety (OR, 3.09, 95%CI, 1.76-5.42, p<0.001), HAMD score (OR, 1.19, 95%CI, 1.09-1.31, p<0.001), TPOAb (OR, 1.002, 95%CI, 1.001-1.002, p<0.001), and TSH (OR, 1.20, 95%CI, 1.10-1.32, p<0.001) were independently associated with SA in MDD patients with AIT. The combination of the four variables well distinguished SA patients from non-SA patients (AUC value:0.80).
Conclusions: Taken together, AIT was closely associated with SA. Regular thyroid examination may help detect SA in MDD patients.