Importance Patients with giant cell arteritis (GCA) may have an increased risk of pulmonary embolism (PE), similar to other systemic vasculitidies; however, no relevant population data are available to date.
Objective To evaluate the future risk and time trends of new venous thromboembolism (VTE) in individuals with incident GCA at the general population level.
Design Observational cohort study.
Setting General population of British Columbia.
Participants 909 patients with incident GCA and 9288 age-matched, sex-matched and entry-time-matched control patients without a history of VTE.
Main outcome measures We calculated incidence rate ratios (IRR) overall, and stratified by GCA duration. We calculated HR of PE and deep vein thrombosis (DVT), adjusting for potential VTE risk factors.
Results Among 909 individuals with GCA (mean age 76 years, 73% women), 18 developed PE and 20 developed DVT. Incidence rates (IR) of VTE, PE and DVT were 13.3, 7.7 and 8.5 per 1000 person-years (PY) in GCA cohort, versus 3.7, 1.9 and 2.2 per 1000 PY in the comparison cohort. The corresponding IRRs (95% CI) for VTE, PE and DVT were 3.58 (2.33 to 5.34), 3.98 (2.22 to 6.81) and 3.82 (2.21 to 6.34) with the highest IRR observed in the first year of GCA diagnosis (7.03, 7.23 and 7.85, respectively). Corresponding fully adjusted HRs (95% CI) were 2.49 (1.45 to 4.30), 2.71 (1.32 to 5.56) and 2.78 (1.39 to 5.54).
Conclusions and significance These findings provide general population-based evidence that patients with GCA have an increased risk of VTE, calling for increased vigilance in preventing this serious, but preventable complication, especially within months after GCA diagnosis.
- Giant Cell Arteritis
- Cardiovascular Disease
- Systemic vasculitis