Life expectancy of hemophilia patients has improved considerably during the past decades and is approaching that of the general population. Hemophilia patients are therefore likely to be confronted with age-related disorders in addition to their primary illness and related diseases. Little is known about the occurrence of age-related co-morbidity, especially cardiovascular disease (CVD), in these patients. Low clotting factor levels are hypothesized to protect against both atherosclerosis and thrombus formation, resulting in a reduced risk of ischemic CVD. CVD mortality has been reported to be lower in haemophilia patients than in the general population, but data on non-fatal CVD are lacking, and no adjustment for CVD risk factors has been made so far.

The aim of our study is to assess the occurrence of CVD and its risk factors in a large cohort of haemophilia patients.

In this prospective multicenter cohort study in a group of 700-800 male patients with haemophilia A or B aged 30 years or older from The Netherlands and the UK, data on CVD history and CVD risk factors will be collected at baseline and compared with the general age-matched male population. Overall QRISK2 cardiovascular risk scores will be calculated and also compared with the general population. During a follow-up period of 5 and 10 years the occurrence of CVD events will be recorded and compared with the expected occurrence based on the QRISK2 scores and with data from the general population.

Inclusion Criteria:

• Haemophilia A or B (mild, moderate or severe)
• Male gender
• Age 30 years or older
• Treated at participating haemophilia treatment center

Exclusion Criteria:

• No specific exclusion criteria

All male haemophilia patients aged 30 years or older who are treated at one of the participating haemophilia treatment centers (Utrecht and Groningen, The Netherlands, and Sheffield, london, Cardiff and Glasgow, UK).

Patients are recruited during regular clinic visits.