Depressive Symptoms and Major Depressive Disorder in Patients Affected by Subclinical Hypothyroidism

Abstract

The relationship between subclinical hypothyroidism and depression is still controversial. Our objective was to compare the prevalence of depressive symptoms and major depressive disorder in a population of patients affected by subclinical hypothyroidism and a control group without thyroid disease. The authors enrolled 123 consecutive outpatients affected by subclinical hypothyroidism undergoing follow-up at the endocrinology department of San Paolo Hospital in Milan and 123 controls without thyroid disease under the charge of general physicians.All patients and controls underwent an evaluation by means of a psychiatric interview; Hamilton Rating Scale for Depression (HAM-D); Montgomery-Asberg Depression Rating Scale (MADRS); and serum thyroid stimulating hormone, free T4, and free T3 levels. Patients were also screened for thyroid peroxidase antibodies and thyroglobulin antibodies. Patients affected by subclinical hypothyroidism had a prevalence of depressive symptoms of 63.4% at HAM-D and 64.2% at MADRS; 22 patients (17.9%) had a diagnosis of depressive episode (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria). The control group had a prevalence of depressive symptoms of 27.6% at HAM-D and 29.3% at MADRS, and only seven controls had a diagnosis of depressive episode. The prevalence of depressive symptoms between these two groups was statistically different. This study underlines a strong association between subclinical hypothyroidism and depressive symptoms, which could have some important diagnostic and therapeutic implications in the clinical practice.

Abnormal brain functional connectivity leads to impaired mood and cognition in hyperthyroidism: a resting-state functional MRI study

“…Yu et al [51] yielded a study showing that high serum TPOAb level in subclinical hypothyroidism after I-treatment of Graves’ disease was an independent risk factor for depression. And TPOAb was also proved to be associated with abnormal neuropsychiatric symptoms in autoimmune thyroid diseases, including Hashimoto's thyroiditis [52] and Hashimoto's encephalopathy [53–55]. The possible mechanisms proposed included autoimmune central nervous system (CNS) vasculitis with or without immune complex deposits, and autoimmune reaction to antigens shared by the thyroid gland and the CNS [56].…”

High levels of Nesfatin-1 in relation to the dysfunction of the hypothalamic–pituitary–adrenal and hypothalamus–pituitary–thyroid axes in depressed patients with subclinical hypothyroidism

“…Although the relationship between depression and SCH remains controversial, an increasing amount of evidence suggests that SCH is associated with neuropsychiatric disorders such as cognitive dysfunction11 and depression 12. Depression is reportedly observed more frequently among individuals with SCH than among those with overt hypothyroidism,13 and patients with SCH exhibit a twofold higher prevalence of depression-like symptoms relative to healthy individuals 14.…”

Subclinical hypothyroidism in paediatric population treated with levothyroxine: a real-world study on 2001–2014 Italian administrative data

“…This attitude could be due to the well-known clinical consequences of a non-treated SH in adults (i.e. increased risk of cardiovascular diseases, depression, lipid disorders, high serum prolactin concentration and negative impact on the haemostatic profile) (20, 21, 22, 23, 24, 25). In particular, specific researches on cardiovascular risk among children with untreated SH showed some metabolic abnormalities (pro-atherogenic abnormalities) in these subjects, suggesting a close monitoring of all cardiovascular risk factors in this patient group (26, 27).…”