288. The Association between Age of Diagnosis and Disease Characteristics in Patients with ANCA-Associated Vasculitis
Creators: name: Bloom1, Jessica
Publisher: name: Zenodo
Year: 2022
Subjects: Vasculitis
ANCA
Abstracts
Giant Cell Arthritis
MPA
GPA
EGPA
Takayasu
IgA vasculitis

description: <strong>Background:</strong> Clinical characteristics often differ between children and adults diagnosed with the same rheumatic condition; however, such comparative data is limited in ANCA-associated vasculitis (AAV). The objective of this study was to examine the relationship between age of diagnosis and disease characteristics in patients with AAV. <strong>Methods:</strong> This was a cross-sectional analysis of all patients with granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA) enrolled in the Vasculitis Clinical Research Consortium (VCRC) Longitudinal Studies, a physician-entered database, from 2013 to 2021. The sample was divided into four cohorts: children (&lt; 18 years old at diagnosis), young adults (18-40 years old at diagnosis), middle-aged (&gt; 40-65 years old at diagnosis), and older adults (&gt; 65 years old at diagnosis). Patients without a listed age of diagnosis were excluded. Missing or unknown data were not included in the calculations for each variable. Continuous variables were reported with medians and interquartile ranges; categorical variables with frequencies and proportions. Group differences were tested via Kruskal-Wallis test for continuous variables and Fisher’s Exact tests for categorical variables. Outcomes included demographics, ANCA type (anti-proteinase 3 (PR3) and anti-myeloperoxidase (MPO)), and clinical characteristics at diagnosis and over time. Sub-analyses were performed within each disease category and ANCA type. <strong>Results:</strong> A total of 1377 patients were included for analysis, including 66 children, 322 young adults, 767 middle aged, and 222 older adults (Table 1). Of the 1377 patients, 852 (62%) had GPA, 165 (12%) had MPA, and 357 (26%) had EGPA. 998 (81%) of all patients were ANCA positive with 641 (64%) positive for PR3-ANCA, 346 (35%) positive for MPO-ANCA, and 11 (1%) positive for both. AAV diagnosed in childhood had a female predominance, which then decreased with age. AAV diagnosed in childhood was also more commonly GPA and ANCA positive with PR3-ANCA predominance and less commonly EGPA. Older adults at diagnosis had more MPA and MPO-ANCA. Both at diagnosis and over time, the group diagnosed in childhood experienced more subglottic stenosis and alveolar hemorrhage. The incidence of skin, ocular, nasal, sinus, renal, gastrointestinal, and nervous system manifestations were also different in at least one age group over time. <strong>Conclusions:</strong> There is an association between age of diagnosis and certain clinical characteristics in patients with AAV, particularly when diagnosed in childhood. Most notably, children diagnosed with AAV experience more subglottic stenosis and alveolar hemorrhage, among other features. An early female predominance in AAV wanes across age groups. While studies often exclude children, sub-analyses of adults with AAV diagnosed in childhood could provide valuable insight into the unique aspects of childhood-onset AAV across the lifespan, allowing for a more evidence-based approach to care and improved outcomes. <strong>Disclosures:</strong> None.