Impaired autonomic function and somatosensory disturbance in patients with treated autoimmune thyroiditis

• Published in: Scientific reports Vol. 14; no. 1; pp. 12358 - 12
• Main Authors: Bazika-Gerasch, Bojana, Kumowski, Nina, Enax-Krumova, Elena, Kaisler, Miriam, Eitner, Lynn Bernadette, Maier, Christoph, Dietrich, Johannes W.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 29.05.2024; Nature Publishing Group; Nature Portfolio
• Subjects: 692/163/2743/1841; 692/617/375/1692; 692/617/375/430; Adult; Aged; Anxiety; Autoimmune thyroiditis; Autoimmunity; Autonomic nervous system; Autonomic Nervous System - physiopathology; Autonomic neuropathy; Cardiovascular system; Female; Heart Rate; Heart rate variability; Humanities and Social Sciences; Humans; Hyperalgesia; Hypothyroidism; Hypothyroidism - complications; Hypothyroidism - drug therapy; Hypothyroidism - physiopathology; Male; Medical treatment; Mental depression; Middle Aged; multidisciplinary; Pain perception; Peripheral neuropathy; Quality of Life; Quantitative sensory testing; Science; Science (multidisciplinary); Sensory evaluation; Somatosensory Disorders - etiology; Somatosensory Disorders - physiopathology; Somatosensory function; Thyroid; Thyroid diseases; Thyroid gland; Thyroiditis; Thyroiditis, Autoimmune - complications; Thyroiditis, Autoimmune - drug therapy; Thyroiditis, Autoimmune - physiopathology; Thyroxine; Thyroxine - blood; Thyroxine - therapeutic use; Hypothyroidism; Autonomic neuropathy; Autoimmune thyroiditis; Heart rate variability; Somatosensory function; Quantitative sensory testing
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-024-63158-w

Despite treatment with levothyroxine, hypothyroidism and autoimmune thyroiditis (AIT) may be associated with reduced quality of life (QoL), an enigmatic condition referred to as "syndrome T". Peripheral neuropathy, described in untreated thyroid disease, could be a contributing mechanism. We analysed autonomic and somatosensory function in 29 patients with AIT and treated hypothyroidism and 27 healthy volunteers. They underwent heart rate variability (HRV) analysis and quantitative sensory testing (n = 28), comprising 13 parameters of small and large nerve fibre function and pain thresholds. Autonomic cardiovascular function was assessed in rest, deep respiration and orthostasis. Additionally, biomarkers for autoimmunity and thyroid function were measured. Anxiety, depression and QoL were assessed using validated questionnaires. 36% of the patients showed at least one sign of somatosensory small or large fibre dysfunction. 57% presented with mild hyperalgesia to at least one stimulus. Several markers of autonomic function and some detection thresholds were related to the antibody titres. Anxiety, depression scores and QoL correlated to antibody titres and HRV measures. Autonomic and somatosensory dysfunction indicate that in treated hypothyroidism and AIT a subgroup of patients suffers from neuropathic symptoms leading to impaired QoL. Additionally, mild hyperalgesia as a possible sensitisation phenomenon should be considered a target for symptomatic treatment.