Session Information
Session Type: Poster Session C
Session Time: 9:00AM-11:00AM
Background/Purpose: Prior studies have found increased prevalence of thyroid disease in patients with ANCA-associated vasculitis (AAV), especially positive myeloperoxidase (MPO)-ANCA, but a majority of the patients in the studies had microscopic polyangiitis (MPA). The aim of this study was to evaluate the risk of thyroid disease between the different forms of AAV, and, to compare the clinical features of AAV in patients with and without thyroid disease.
Methods: Patients with the 3 forms of AAV (granulomatosis with polyangiitis (GPA), MPA and eosinophilic granulomatosis with polyangiitis (EGPA)) enrolled in a prospective, multicenter, longitudinal study were included. All patients were followed with standardized data collection. Information on thyroid disease was systematically collected. Logistic regression was used to evaluate the association of thyroid diseases with different clinical and laboratory variables.
Results: The study included 1,315 patients with AAV, 55% female. Clinical diagnosis was GPA in 866 (66%), MPA in 167 (13%) and EGPA in 282 (21%). Mean age at entry into the cohort was 52.5 ±15.8 years. Thyroid disease was present in 163 patients (13%) including hypothyroidism in 145 (11%) and hyperthyroidism in 18 (1.4%). Women were more likely to have thyroid disease (OR 3.22, 95% CI 2.19, 4.75).
The age- and sex-adjusted risk of hypothyroidism by type of AAV and ANCA are in Table 1. Hypothyroidism was associated with positivity for p-ANCA or MPO, but not type of AAV (Table 1). Analyses in the subset of patients with GPA demonstrated that hypothyroidism was associated with MPO-ANCA positivity (OR 3.01, 95% CI 1.80, 5.02 compared to positive PR3) and p-ANCA (OR 2.32, 95% CI 1.27, 3.94 compared to c-ANCA).
The clinical features of AAV were compared between patients with and without hypothyroidism (Table 2). Patients with AAV and hypothyroidism had an increased risk of venous thrombosis.
Conclusion: This study confirms an association of hypothyroidism with p-ANCA/MPO in patients with AAV. Further strengthening this observation is the association of thyroid disease with MPO ANCA in the subset of patients with GPA. Previously hypothesized mechanisms for this finding include homology between thyroid peroxidase antibodies and MPO, or, general loss of tolerance to peroxidases. The increased risk of venous thromboembolism in patients with AAV and hypothyroidism warrants further investigation and may be due to additional effects of hypothyroidism on endothelial dysfunction or hypercoagulability.
To cite this abstract in AMA style:
Kermani T, Cuthbertson D, Carette S, Khalidi N, Koening C, Langford C, McAlear C, Monach P, Moreland L, Pagnoux C, Seo P, Specks U, Sreih A, Warrington K, Merkel P. Thyroid Disease in Patients with ANCA-Associated Vasculitis [abstract]. Arthritis Rheumatol. 2020; 72 (suppl 10). https://acrabstracts.org/abstract/thyroid-disease-in-patients-with-anca-associated-vasculitis/. Accessed .« Back to ACR Convergence 2020
ACR Meeting Abstracts - https://acrabstracts.org/abstract/thyroid-disease-in-patients-with-anca-associated-vasculitis/