Short summary

AAV is a systemic vasculitis characterized by necrotising inflammation of small vessels, circulating autoantibodies and with a wide range of clinical presentations. The aetiology of AAV is still not fully understood but may include genetic predisposition, environmental factors and immunological disturbance.

It is a rare disease and can be fatal or organ threatening. The treatment often requires potent immunosuppressant. It is still a challenge to predict the disease course and risk of relapse in these patients. Despite therapy, the mortality ratio is still increased and may partly be caused by accelerated atherosclerosis and severe infections.

The majority of previous studies of AAV have been clinic based. Previous population based studies in Scandinavian/European settings has been retrospective and solely based on medical reports.

Rationale

AAV is a systemic vasculitis comprising three clinical syndromes: Granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis and microscopic polyangiitis. It is a complex group of diseases characterized by necrotising inflammation of small vessels, circulating autoantibodies directed at neutrophil cytoplasmic constituents (i.e. ANCAs) and with a wide range of clinical presentations. The aetiology of AAV is still not fully understood but may include genetic predisposition, environmental factors and immunological disturbance. The pathogenesis of AAV has been extensively studied. Infection with Staphylococcus Aureus may trigger the disease in predisposed individuals. ANCA it selves and neutrophile micro particles may also play a pathogenic role.

It is a rare disease and can be fatal or organ threatening. The treatment often require potent immunosuppressant's. Despite therapy, the mortality ratio is still increased and could partly be caused by accelerated atherosclerosis and severe infections. It is still a challenge to predict the disease course and risk of relapse in these patients. This may result in both under- and over treatment.

The aim of this study is:

To establish a population based cohort of patients with ANCA associated vasculitis (AAV) and follow them prospectively for the purpose of:

• Characterization of the cohort with respect to clinical manifestations, disease pattern and comorbidity and establish an associated biobank
• Identification of possible prognostic factors with respect to mortality, disease activity, damage and comorbidity, especially cardiovascular disease (CVD).

This study will add important information's to the existing knowledge about AAV with respect to epidemiology, prognosis and disease patterns. In clinic based studies, patients with relatively mild disease are often not represented. A population based approach will allow us to study this population which is highly relevant in order to identify prognostic factors for a good outcome. Furthermore, prospective follow-up of a clinical well characterized cohort combined with a biobank is a unique opportunity for further studies on patients with AAV.

Description of the cohort

Patients with AAV will be retrieved from the diagnose register for in- and out patients in Southern Denmark and register for autoimmune tests for positive ANCA analyses.

Patients will be invited to a yearly project visit in 5 years. Blood and urine samples will be stored in a biobank.

Data and biological material

Blood and urine samples will be stored in a biobank in Odense Patient data Explorative Network (OPEN).

Incident patients will be asked to participate in further investigations (e.g. PET-CT).

Disease manifestations, medication and further comorbidity will be registered (see table)

Data will be registered in a REDCap database, supported by OPEN.

Collaborating researchers and departments

Department of Rheumatology, Odense University Hospital

• Consultant Anne Voss, MD, PhD
• Robin Christensen, BSc, MSc, PhD

Musculoskeletal Statistics Unit, The Parker Institute, Department of Rheumatology, Copenhagen University Hospital

• Clinical Professor Torkell Ellingsen

Clinical Biochemistry and Pharmacology, Odense University Hospital

• Professor Niels Heegaard, MD, DMSc

Institute of Pathology, Odense University Hospital

• Professor Niels Marcussen

Department of Nuclear Medicine, Odense University Hospital

• Professor Poul-Flemming Højlund-Carlsen

Department of Nephrology, Odense University Hospital

• Hans Dieperink, MD

Department of Rheumatology, Odense University Hospital, Svendborg

• Inger Marie Jensen Hansen, MD

King Christian X's Hospital for Rheumatic Diseases, Graasten

• Professor Kim Hørslev-Petersen, MD

Department of Rheumatology, Sydvestjysk Sygehus, Esbjerg

• Ada Colic, MD