Giant cell arteritis and vascular disease-risk factors and outcomes: a cohort study using UK Clinical Practice Research Datalink.

Objective: To evaluate the associations between GCA and vascular diseases and other comorbidities in patients with GCA compared with non-vasculitis patients.
Methods: Using the UK-based Clinical Practice Research Datalink we identified 9778 newly diagnosed GCA patients in 1990-2014, and up to 10 non-vasculitis patients randomly matched to each case on age, sex, practice and years of history before cohort entry. We compared the distributions of 9 different pre-existing vascular diseases and 11 other comorbidities, and risks of incident vascular diseases and other comorbidities after cohort entry between GCA and non-vasculitis patients.
Results: Patients with GCA were more likely to have a history of vascular diseases and other comorbidities except myocardial infarction, type 2 diabetes, obesity and cancer, compared with non-vasculitis patients. Patients with GCA had increased risks for all types of incident vascular disease compared with non-vasculitis patients: adjusted hazard ratios were 1.57 (95% CI: 1.36, 1.82) for myocardial infarction, 1.41 (95% CI: 1.29, 1.55) for stroke, 1.75 (95% CI: 1.49, 2.06) for peripheral vascular disease, 1.98 (95% CI: 1.50, 2.62) for aortic aneurysm and 2.03 (95% CI: 1.77, 2.33) for venous thromboembolism. Patients with GCA also had increased risks for other incident comorbidities (type 2 diabetes, depression, etc.), but not for cancer.
Conclusion: Patients with GCA had more prior vascular diseases and other comorbidities before the diagnosis and they also had increased risks for incident vascular diseases and many other incident comorbidities after the diagnosis compared with non-vasculitis population.