Cardiovascular disease is among the leading causes of death in patients with ANCA-associated vasculitis (AAV), who face a 2-3-fold higher risk of cardiovascular events and mortality compared to the general population. This increased risk is due to risk factors such as immunosuppression, traditional cardiovascular risk factors i.e. hypertension and diabetes, chronic kidney disease, and inflammation. Despite this, no AAV-specific guidelines for cardiovascular risk management and screening are available.

This PhD thesis explores the contemporary epidemiology of cardiovascular disease in AAV disease, examines potential treatment targets for improving cardiovascular survival and explores non-invasive cardiovascular screening strategies. It consists of three epidemiological studies (two retrospective cohort studies and one nested case-control study) and two observational cross-sectional studies of the same cohort of outpatients with AAV in long-term disease remission.

Key findings:

• Study I: AAV is associated with a higher risk of coronary examinations, myocardial infarction, atrial arrhythmias, atrial- and venous thromboembolisms throughout three consecutive time periods.
  
  However, the risk of mortality has decreased over time.
• Study II: AAV is associated with an increased risk of cardiovascular disease, even before the diagnosis has been established. The risk increases in the immediate proximity of the diagnosis.
• Study III: AAV is associated with a higher prevalence of major ECG abnormalities, such as left ventricular hypertrophy, ST-T deviations and atrial fibrillation, which are similarly associated with higher cardiovascular mortality.
• Study IV: AAV is associated with a reduced cardiac autonomic function, increased arterial stiffness, and decreased myocardial perfusion.
• Study V: AAV is associated with more echocardiographic and cardiac MRI abnormalities such as diastolic dysfunction, subclinical left ventricular systolic dysfunction and myocardial edema/fibrosis compared to matched controls.

Overall, this thesis provides an update into the cardiovascular risks associated with AAV, advocating for timely screening, while also enhancing our current understanding of ECG assessment and non-invasive imaging strategies for AAV patients in disease remission.