AB0719 ASSOCIATION BETWEEN FIBROMYALGIA AND CHRONIC AUTOIMMUNE THYROIDITIS. RETROSPECTIVE OBSERVATIONAL DATA FROM A MONOCENTRIC ENDOCRINOLOGIST-RHEUMATOLOGIST COLLABORATIVE ANALYSIS
Authors: F. Fischetti, S. Bernardi, S. Lovriha, F. Bozzao, P. Tomietto, B. Fabris
Journal: Annals of the Rheumatic Diseases (2021)

Background: Endocrine and metabolic imbalance conditions can affect the development of subjective abnormal perceptions within fibromyalgia (FMR). In the case of autoimmune thyroid disease (ATD), prolonged, clinically active states of impaired glandular function may be associated with an FMR-type condition. Less clear is the association between subclinical or rapidly well-controlled states of thyroid disease and the presence of FMR, since this assessment, although analysed in some previous studies, was usually performed on cohorts of subjects where the absence of any other confusing factors was not well defined. Objectives: To evaluate the prevalence of subclinical autoimmune thyroid disease, or functionally controlled autoimmune thyroid disease, in a retrospective cohort of consecutively diagnosed patients suffering from fibromyalgia condition. Methods: Over a 2 years period of time (2018-2019) a monocentric joint evaluation was activated with the endocrinology section of our healthcare area in order to consecutively monitor the subjects belonging to both specialist clinics. Patients with ATD were not unfrequently firstly evaluated in the rheumatology ambulatory. Diagnosis of FMR was defined according to the American College of Rheumatology 2010/2011 criteria. At the same time, at the rheumatology clinics, all cases addressed with diagnosis of fatigue or chronic pain of no defined origin were analysed in order to carefully identify any associated, comorbidity problems. The diagnosis of ATD was confirmed according to recognized international criteria. The following results will focus on subjects with chronic Hashimoto type Thyroiditis (HT). Results: Among the HT patients, 98% were women, aged between 28 and 64. Over the 2 years considered period of time, 65 subjects suffering from HT, showing no active disease or unstable endocrine function were addressed to the rheumatology clinics owing to FMR related symptoms. Among them, 55 (84.6%) had a confirmed diagnosis of FMR. Within this time, we recognized 239 consecutive diagnoses of FMR in subjects aging 22-76 years, with a number of 114 found to be devoid of factors (other than ATD) able to be responsible for chronic pain, except for a modest component of situational anxiety, or mild mood depression, not requiring any specific drug intervention. Among the 114, so called “primary” FMR, 35.6% showed to suffer from TCH, under confirmed clinical/hormonal remission, or in a preclinical, early stage of onset. Within the 125 subjects, carrying a FMR condition related to previous or associated fostering pathology, 26.8% were positive for current or previous thyroid problems. The prevalence of TCH, in the “secondary” FMR conditions differed significantly (p&lt;0.01) from that of other FMR promoting diseases (eg connective tissue diseases, such as Sjogren Syndrome), except for moderate-severe mood disorders and/or anxiety, and the most severe chronic osteoarthritis conditions, showing a confirmed secondary neuropathy. Conclusion: Although limited in number, the here reported data confirm the hypothesis of a significant association between ATD and FMR, even in subjects who were considered to be in a subclinical condition or in full clinical remission by the endocrinology colleagues. The physiopathology of this association needs further appropriate insights. Acknowledgements: We thank Dr Alberto Petterle for his previous helpful contribution Disclosure of Interests: None declared