Israel Medical Association Journal

The potential influence of seasonal variations on vasculitis is unclear. Emerging evidence has suggested that seasonal factors may play a role in the onset of vasculitis. We extracted data from the electronic medical records at Clalit Health Services (CHS), Israel's largest health maintenance organization. We identified patients older than 18 years of age with new onset of giant cell arteritis (GCA), ANCA-associated vasculitis, immunoglobulin A (IgA) vasculitis, and Behçet's disease from 2007 to 2021. We constructed a time series of new vasculitis cases per month and explored the potential impact of seasonality on the disease onset. Our cohort included 4847 patients, including 2445 with GCA, 749 with ANCA-associated vasculitis (AAV), 547 with IgA vasculitis, and 1106 with Behçet's disease. We observed a decreased risk of GCA in September (relative risk [RR] 0.84, [95% confidence interval] 95%CI 0.72–0.98) and a significant reduction in AAV incidence in August (RR 0.68, 95%CI 0.48–0.96). For IgA vasculitis, an elevated risk was noted in February (RR 1.58, 95%CI 1.02–2.45), while Behçet's disease showed an increased risk in January (RR 1.25, 95%CI 1.02–1.55). No association was found between any specific season and the onset of vasculitis for any of the studied conditions. Our study results indicate that the onset of vasculitis conditions may be influenced by environmental factors associated with seasonality.

Background: Giant cell arteritis (GCA) is a large vessel vasculitis predominantly affecting patients over 50 years, typically managed with glucocorticoids, with treatment varying on individual patient needs. While effective for GCA, long-term glucocorticoids use poses significant risks, including the development of osteoporosis, a metabolic bone disease common in older individuals. This overlap poses a significant clinical challenge, as the treatment for GCA inadvertently raises the risk of osteoporosis and necessitates careful balance to manage both conditions effectively.

Objectives: To investigate the occurrence of osteoporosis and other co-morbid conditions in patients with GCA treated with glucocorticoids.

Methods: A retrospective cross-sectional analysis of GCA patients examined the correlation between GCA and osteoporosis by searching the Clalit Health Service database for patients over 50 years of age from January 2002 to January 2018. In addition, we conducted a logistic regression analysis stratifying for other co-morbidities to evaluate the independent association between GCA and osteoporosis.

Results: In total, 6607 GCA patients were compared with 36,066 age- and sex-matched controls. The study revealed a higher prevalence of osteoporosis in the GCA group (43%) compared to controls (27%) (odds ratio [OR] 2.06, 95% confidence interval [95%CI] 1.95–2.17). In addition, hypertension, hyperlipidemia, diabetes mellitus, and ischemic heart disease were more prevalent among GCA patients. After stratifying for cardiovascular co-morbidities, GCA remained independently associated with osteoporosis (OR 2.1, 95%CI 1.96–2.26, P < 0.001).

Conclusions: Glucocorticoid-treated GCA is independently associated with osteoporosis. Healthcare providers must consider this added aspect of GCA for the treatment and management of patients.