High Risk of Stroke in ANCA-associated Vasculitis

A Population-Based Study

Dennis Tabakovic; Rona Smith; David Jayne; Aladdin J. Mohammad


Rheumatology. 2023;62(8):2806-2812. 

In This Article

Abstract and Introduction


Objective: To determine the incidence rate, predictors and outcome of stroke in a population-based cohort of individuals with ANCA-associated vasculitis (AAV).

Methods: The study included 325 patients diagnosed with AAV from 1997 through 2016 in a defined geographic area of Sweden. Patients who suffered a stroke were identified from Riksstroke, a national Swedish stroke register established in 1994, and the Skåne Healthcare Register (SHR), which includes data for all inhabitants of Skåne since 1998. Case record review was carried out to confirm the diagnosis of stroke in AAV patients identified in the SHR. The incidence rate of stroke was calculated per 1000 person-years of follow-up. Using data from the Swedish general population, the standardized incidence ratio (SIR) of stroke was estimated. Cox regression analysis was utilized to investigate survival and predictors of stroke.

Results: Twenty-five subjects (8%) suffered a stroke during 2206 person-years of follow-up. The incidence rate of stroke in AAV was 11.3/1000 person-years (95% CI 6.9, 15.8). Patients with AAV showed an increased risk of stroke compared with the general population [SIR 1.85 (95% CI 1.27, 2.59)], with a greater risk for those <65 years of age [SIR 3.19 (95% CI 1.53, 5.88)]. Higher platelet count at AAV diagnosis was an independent predictor of stroke [hazard ratio 1.14 (95% CI 1.00, 1.29)]. There were no differences in survival or other outcome measures between AAV patients with and without stroke.

Conclusions: The incidence rate of stroke in AAV is higher than in the general population. High platelet count at AAV diagnosis was associated with an increased risk of stroke.


ANCA-associated vasculitis (AAV) is an umbrella term for a group of autoimmune diseases characterized by inflammation of the small blood vessels, including granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangiitis (EGPA). AAV is characterized by systemic inflammation causing dysfunction of or damage to multiple organs including the kidneys, lungs and upper respiratory tract.

Since the introduction of AAV treatment with cytostatic drugs such as cyclophosphamide combined with high doses of glucocorticosteroids, the prognosis and survival has improved dramatically,[1] transforming AAV from a disease with 80% mortality in the 12 months following diagnosis to a more stable and manageable condition with a 5 year survival rate of 72%.[2] However, patients with AAV exhibit a higher rate of comorbidities compared with the general population. This includes a 4-fold rate of venous thromboembolic disease and a 5-fold rate of severe infection and septicaemia,[3] comorbidities with consequences to the individual and to the economic and societal burden of AAV.[4]

Research has shown an increased risk of cardiovascular events in individuals with AAV.[5–7] A population-based study of a cohort of AAV patients in southern Sweden demonstrated an increased rate of ischaemic heart disease compared with the general population as well as a more frequent presence of traditional risk factors for cardiac disease, including hypertension and diabetes.[3] An increased rate of atherosclerosis in patients with chronic inflammatory disease, including AAV, has also been identified and is a possible risk factor contributing to cardiovascular events in AAV.[8,9]

While the risk of cardiovascular events in AAV has been well researched, only a few studies have investigated the incidence of stroke in patients with AAV,[6,7,10–12] and results have been inconsistent with respect to stroke risk. In addition, most of the available studies originate from tertiary referral centres and, unlike population-based studies, can be associated with selection and referral bias.

In this population-based study from southern Sweden utilizing a large, validated cohort of patients with ANCA-associated vasculitis, we aimed to determine the incidence rate of stroke in AAV compared with the general population and explore possible predictors and outcomes of stroke in AAV.