Association between depression, daytime sleepiness, and thyroid function in patients with thyroid hormone replacement therapy

Abstract

Objective: Thyroid disease may be associated with various psychiatric disorders, such as mild depression and anxiety. Here, we examined the association between thyroid hormone levels and depression and excessive daytime sleepiness (EDS). Methods: Participants were patients who visited Gyeongsang National University Hospital for thyroid hormone replacement therapy due to chronic autoimmune thyroiditis or thyroidectomy after diagnosis of thyroid cancer between October 2012 and May 2015. Thyroid function was measured in all patients, who were also evaluated for depression, anxiety, daytime sleepiness, and resilience using the Hospital Anxiety and Depression Scale, Epworth Sleepiness Scale, and Connor-Davidson Resilience Scale. Results: The patient group consisted of 39 cases of primary hypothyroidism due to chronic autoimmune thyroiditis, especially Hashimoto's thyroiditis, and 57 cases due to total thyroidectomy after thyroid cancer. The mean ages for the participants were 52.32±5.99 years. In patients with hypothyroidism due to chronic autoimmune thyroiditis or thyroid cancer, triiodothyronine (T3) (β=0.291, p=0.013) was associated with depression. Both T3 (β=-0.351, p=0.003) and free thyroxine (β=-0.346, p= 0.008) were associated with EDS. Conclusion: We found that depression and EDS may be associated with T3 levels in patients with hypothyroidism receiving thyroid hormone replacement therapy. Therefore, we suggest that there may be a need to consider T3 levels in patients with thyroid hormone replacement therapy who complain of depression or EDS. Copyright ? 2020 Korean Academy of Sleep Medicine