Both sensorimotor and autonomic neuropathy may be common in hypothyroidism, despite treatment

A new study may provide a previously unknown reason for reduced quality of life in treated hypothyroidism (syndrome T). Systematic investigations of persons with treated hypothyroidism revealed unique signs of sensorimotor dysfunction in quantitative sensory testing (QST). Being marked by thermal and mechanical hypersensitivity, the pattern differs from the constellation seen in diabetes and other conditions leading to polyneuropathy. This may explain some of the sensory symptoms of syndrome T. Additionally, the study found reduced heart rate variability (HRV), depending on the titres of thyroid autoantibodies. This observation, indicating possible autonomic neuropathy, could explain the components of syndrome T that affect the circulatory system. Other results of the study included that both anxiety and depression were significantly more expressed in subjects with autoimmune thyroiditis and that they were also associated with antibody titres. The autonomic function significantly correlated with anxiety and depression, too. Additionally, the depression percentiles in the hospital anxiety and depression scale (HADS) were negatively associated with step-up deiodinase activity (SPINA-GD). In a control group with normal thyroid function, both autonomic and sensorimotor function correlated with the thyroid’s secretory capacity (SPINA-GT).