Objective: The exact mechanism of arterial stiffness in fibromyalgia (FM) remains unclear. The present study aimed to evaluate the association between thyroid function and markers of arterial function in postmenopausal FM patients.
Methods: This study included 163 postmenopausal FM patients without any known cardiovascular diseases and within a normal reference range of thyroid-stimulating hormone (TSH) level. Clinical parameters including the Fibromyalgia Impact Questionnaire (FIQ), the pain visual analogical scale (VAS) and tender point counts were measured. Vascular function was assessed by brachial-ankle pulse wave velocity (baPWV) and flow-mediated dilation (FMD). We evaluated the associations between arterial markers and serum TSH, free thyroxin, as well as serum thyroidperoxidase autoantibody (TPO Ab).
Results: Patients with a high baPWV (≥ 1490 cm/s) showed more positive TPO Ab (65% vs. 10%, P = 0.006) than those with a normal baPWV. Additionally, the baPWV values of patients with positive TPO Ab were significantly different from those with negative TPO Ab. Age, FIQ and TPO Ab were significantly correlated with baPWV and FMD (all P < 0.05). Multiple linear regression analysis revealed that the only significant predictors of baPWV were age, FIQ and the presence of TPO Ab after adjustment for traditional risk factors. A significant association was also found between FMD and positive TPO Ab.
Conclusion: Age, functional status and presence of TPO Ab were significantly associated with increased arterial stiffness in postmenopausal FM patients. Given the combined thyroid autoimmunity in FM patients, a re-evaluation of the effects on the vasculature may be necessary.
Keywords: fibromyalgia; flow-mediated dilation; pulse wave velocity; thyroid-stimulating hormone.
© 2014 Asia Pacific League of Associations for Rheumatology and Wiley Publishing Asia Pty Ltd.