Background Venous thromboembolic events (VTE) and cerebrovascular accidents (CVA) are serious health problems in the general population and appear to be more frequent in patients with chronic inflammatory disorders.
Objectives The purpose of the study is to determine the incidence of VTE and CVA in patients with giant cell arteritis (GCA).
Methods We retrospectively reviewed a population-based incidence cohort of patients with GCA diagnosed between 1950 and 2009 based on American College of Rheumatology 1990 GCA classification criteria. We compared this cohort with subjects without GCA of similar age, sex, and calendar year from the same population. All subjects were followed longitudinally through all available community medical records until death, migration from Olmsted County or 31 December 2013. The occurrence of VTE (deep venous thrombosis or pulmonary embolism), and CVA (hemorrhagic stroke, ischemic stroke, transient ischemic attack (TIA), amaurosis fugax), were ascertained by review of the medical records. The cumulative incidence of VTE and CVA in patients with and without GCA, adjusted for the competing risk of death, was estimated and compared using methods by Gray.
Results The study population included 244 patients with GCA and 240 non-GCA subjects. The GCA cohort consisted of 193 (79%) women and 51 (21%) men, with mean (±SD) age 76.0 (±8.2) years and a median follow-up 10.2 years. The non-GCA cohort consisted of 190 (79%) women and 50 (21%) men, mean age 75.8 (±8.5) years with a median follow-up 10.8 years. The GCA cohort was followed for a total of 2,480 person-years, while the non-GCA cohort was observed for 2588 person-years. Occurrence of VTE prior to GCA incidence/index date was similar between the two cohorts: 10 episodes (4%) in GCA cohort versus 8 episodes (3%) in non-GCA cohort (p=0.81). During follow-up, 16 patients with GCA and 10 non-GCA subjects developed VTE. The 10-year cumulative incidences (±SE) of VTE were 6.3% (±1.6) among patients with GCA and 3.7% (±1.3) among non-GCA patients (p=0.22).
CVA had occurred prior to the index date in 18 (7.3%) patients with GCA and 18 (7.5%) non-GCA patients (p=0.96). During follow-up, 30 patients with GCA and 27 non-GCA subjects developed CVA. The 10-year cumulative incidences (±SE) of stroke were similar between patients with GCA [8.5% (±1.9)] and non-GCA subjects [9.2% (±2.0); p=0.94]. The 10-year cumulative incidences (±SE) of TIA were also similar between patients with GCA [2.3% (±1.0)] and non-GCA subjects [1.7% (±0.8); p=0.97]. Patients with GCA had a higher cumulative incidence of amaurosis fugax compared to controls [1.2% (±0.7) versus 0%; p=0.045]. Mean age at first event did not differ between patients with GCA and non-GCA subjects for VTE (81.3 versus 85.9 years; p=0.16) or CVA (80.6 versus 83.8 years; p=0.30).
Conclusions In this population based-cohort, patients with GCA were at an increased risk for amaurosis fugax; however, the risk of VTE, stroke and TIA was not increased compared to non-GCA subjects.
Disclosure of Interest None declared