Ab1307 Prevalence and Causes of Hospitalization and Mortality in Giant Cell Arteritis: Analysis of a Monocentric Retrospective Cohort of Patients

Background: Giant Cell Arteritis (GCA) is the most frequent vasculitis among people above the age of 50 years. GCA is associated with several irreversible outcomes, comorbidities, and treatment side effects, which can lead to hospitalization. Objectives: The aim of this study was to analyze prevalence and causes of hospitalization and mortality in GCA patients during the first 5 years after diagnosis. Methods: We analyzed a cohort of 150 patients meeting the 2022 ACR/EULAR criteria for GCA 1, diagnosed between 2003 and 2021 in our Center, and followed up for at least 6 months. Clinical data were collected in the first 5 years after diagnosis. Hospitalizations at diagnosis and day-hospital admissions were excluded. Statistical analysis was performed with Kaplan-Meier analysis (R Ecosystem). Results: We enrolled 150 patients F 69%; M 31%; median age at diagnosis 73 (IQR 67-78) years; diagnostic latency 6 (IQR 3-13) weeks with GCA: 95 (63%) had cranial vasculitis (C-GCA), 22 (15%) large-vessel vasculitis (LV-GCA), and 33 (22%) both. Fifty-two (35%) patients were treated with glucocorticoids (GCs) alone, 52 (35%) with tocilizumab (TCZ), and 46 (30%) with methotrexate (MTX). Seventy-four patients (49%) had at least one hospitalization, with 43 having 1 median time after diagnosis 18 months (95% CI: 12-18) (Graph 1) and 31 having 2 or more. We recorded a total of 135 hospitalizations, with an average of about 2 hospitalizations per patient and 11 days of hospitalization length per patient. Patients hospitalized during follow-up had higher scores of the modified rheumatic disease comorbidity index (mRDCI) and the Charlson comorbidity index (CCI) at diagnosis median mRDCI 1 (IQR 1-2); median CCI 4 (IQR 4-5) compared to non-hospitalized patients median mRDCI 1 (IQR 0-1); median CCI 4 (IQR 3-5) (p mRDCI: 0,0043; p CCI: 0,0365). Six hospitalizations were caused by GCA relapse (3 for temporal headache, 1 for visual impairment, 1 for polymyalgia rheumatica, and 1 for anemia and masseter claudication), occurring after a median time after diagnosis of 18 (IQR 12-42) months. GCs were increased in 4 cases, MTX was changed to TCZ in 1 case, and TCZ was added to GCs in 1 case. In the remaining 129 cases, main causes of hospitalization were infectious diseases (29%), circulatory system diseases (25%) and surgery (13%, of which 9% emergency surgery). Among infections, main sites were respiratory tract (36%), urinary tract (19%), sepsis (14%), gastrointestinal tract (12%), and skin (7%). Most patients were admitted to internal medicine unit (29%), followed by cardiology and cardiac surgery units (18%), general surgery and vascular surgery units (15%), and orthopedics unit (10%). In addition, 10 patients (8%) were admitted to the intensive care unit. On admission, 27 patients (21%) had an active GCA and patients were taking a GC dose of 10 mg or lower in 80 cases (61%) and higher than 10 mg in 51 cases (39%), and an immunosuppressive therapy in 61 cases (47%), of which 35 TCZ and 26 MTX. Fifty-six irreversible GCA complications occurred in 47 patients (31%), including 29 (52%) visual impairment and 18 (32%) aortic aneurisms. Seventeen patients (11%) passed away during follow-up median age 83 (IQR 80-88) years; median time after diagnosis 30 (IQR 18-42) months, 2 of whom during a hospital stay: 8 (47%) died of infection, of which 7 pneumonia and 1 peritonitis, 7 (41%) of cancer, 1 of cardiac arrest, and 1 undetermined. Survival probability was 89% (95% CI: 84-94) at 5 years (Graph 2). Conclusion: Patients with GCA have a high risk of hospitalization occurring in about half of patients during follow-up. Infectious diseases and circulatory system diseases were the main causes of hospitalization. In our cohort, GCA itself did not contribute directly to increase mortality, as no patient died of vasculitis. Nevertheless, immunosuppressive therapy may have played a role, as the primary causes of death were infectious diseases and malignant neoplasms. REFERENCES: 1 Ponte C., et al. Arthritis Rheumatol. 2022. PMID: 36350123. Acknowledgements: NIL. Disclosure of Interests: None declared.