ROAR STUDY

The Risk of Aneurysm Rupture (ROAR) study is the largest research project of its kind in the world and aims to transform how we assess the risk of brain aneurysms rupturing. Unruptured brain aneurysms (bulges or swellings of the blood vessels in the brain) are surprisingly common, affecting around 3% of the population. While many never cause harm, some can rupture (about 1% per year) and lead to a rare type of stroke called subarachnoid haemorrhage (SAH), which is fatal in about 30% of cases. To prevent this, doctors can treat aneurysms before they rupture. However, these treatments carry significant risks, with complication rates between 5% and 8%. Hence it is crucial to be able to identify which aneurysms are high risk of rupturing, so treatment is given only when it’s likely to do more good than harm. Currently, tools like the PHASES score are used to estimate a patient’s 5-year rupture risk, but these tools have limitations and have never been validated in the UK. The ROAR study is tackling this challenge by following up over 20,00 patients with unruptured brain aneurysms, using national databases of hospital admissions and deaths. Currently, ROAR includes more than 100,000 years of patient follow-up which 30 times more than any previous study. The goal of this study is to test the accuracy of the PHASES score and to develop better, more reliable prediction models to guide treatment decisions. This will help ensure that patients get the right care at the right time, potentially saving lives and avoiding unnecessary procedures.