Risk of Aneurysm Rupture (ROAR) Study: measuring the rupture risk of unruptured intracranial aneurysms in the UK

Plain English Summary

Background and study aims
An aneurysm is a bulge in a blood vessel due to a weakness in its wall. They are common and 3% of people have them in the brain. They can burst and cause bleeding which frequently leaves people dead or disabled. Bleeding can be prevented by procedures to treat the aneurysm. However, these procedures can cause serious complications such as stroke. They should therefore only be performed in patients whose risk of bleeding is higher than the risk of complications from the procedures.
The problem is that we are not sure exactly what the risk of bleeding from an aneurysm is. The best estimates come from the previously published PHASES study. This proposed a score based on six items, like patient age and aneurysm size, to estimate the risk of a brain aneurysm bleeding over the next 5 years. However, the PHASES score has several design flaws and neurosurgeons are unsure how accurate it is. For example, 4 out of 5 patients in the study were either Finnish or Japanese, who are the two populations in the world postulated to have a higher risk of rupture than other populations. It is therefore not possible to be sure if this applies to patients in the UK. Researchers therefore want to study a large number of patients with aneurysms that have not burst, who are also neither Finnish nor Japanese, to see which ones go on to burst and bleed.
The first aim of this study is therefore to determine whether or not the PHASES score is accurate in a UK population. Its second aim is to see if using more detail about individual patients and their aneurysms results in more accurate personalised risk estimates. The third aim of the study is to assess whether the short-term risk estimates from PHASES (which in 80% of cases come from the first year after diagnosis) are applicable to the remainder of a patient’s lifetime. Answers to these questions will be of huge benefit by aiding decision making for patients with aneurysms and protect them from the harm of over- or under-treatment.

Who can participate?
Patients aged over 18 with an unruptured intracranial aneurysm diagnosed between 2006 and 2020. As this study is being conducted using pre-existing medical records it does not require any patients to actively participate in the study.

What does the study involve?
The researchers will identify eligible patients from neurosurgical units throughout the UK and collect details, such as their demographics, relevant medical history and aneurysm size and location, from local hospital records. They will then search all of these patients against national databases for hospitals admissions (and deaths) in England, Wales and Scotland to see which patients went on to have a bleed from their aneurysm. All of the data collection, both the hospital records and databases for hospital admissions, is from medical records which already exist. Once the rupture events occurring after diagnosis have been identified, the researchers will build predictive models for aneurysm rupture risk.

What are the possible benefits and risks of participating?
Because the data is retrospective and patients will not be actively participating, there are no direct benefits or risks to the patients involved. The use of a patients’ medical records will not influence the neurosurgical care they have already received. The results from this study, including a better understanding of predicting rupture risk, may change the way that unruptured aneurysms are managed in the UK. This may benefit patients in the future if their previous estimates of rupture risk are inaccurate.

Where is the study run from?
University Hospitals Southampton NHS Foundation Trust (UK)

When is the study starting and how long is it expected to run for?
August 2018 to July 2034

Who is funding the study?
Investigator initiated and funded

Who is the main contact?
Prof Diederik Bulters
d.bulters@soton.ac.uk

Study website

Contact information

Mr Diederik Bulters
Public, Scientific

Department of Neurosurgery
Southampton General Hospital
Tremona Road
Southampton
SO16 6YD
United Kingdom

ORCID ID	0000-0001-9884-9050
Phone	+44 (0)2381205511
Email	d.bulters@soton.ac.uk

Mr Sam Hall
Scientific

Department of Neurosurgery
Southampton General Hospital
Tremona Road
Southampton
SO16 6YD
United Kingdom

Email	SamuelRichards.Hall@uhs.nhs.uk

Study information

Eligibility

Locations

Countries of recruitment

• England
• United Kingdom
• Wales

Study participating centres

Sponsor information

University Hospital Southampton NHS Foundation Trust
Hospital/treatment centre

Tremona Road
Southampton
SO16 6YD
England
United Kingdom

Phone	+44 (0)2380 777222
Email	sharon.davies-dear@uhs.nhs.uk
Website	http://www.uhs.nhs.uk/home.aspx
"ROR"	https://ror.org/0485axj58

Funders

Funder type

Other

Results and Publications

Study outputs

Editorial Notes

17/07/2024: The recruitment end date was changed from 31/07/2024 to 31/07/2025.
15/04/2024: The following changes have been made:
1. The target number of participants was changed from 22,781 to 20,000.
2. The following study participating centres were added: United Leeds Teaching Hospitals NHS Trust, Barking, Havering and Redbridge University Hospitals NHS Trust, St George's University Hospitals NHS Foundation Trust, Newcastle upon Tyne Hospitals NHS Foundation Trust, University Hospitals Birmingham NHS Foundation Trust and Lancashire Teaching Hospitals NHS Foundation Trust.
3. A study contact was updated.
4. The intention to publish date was changed from 01/08/2024 to 31/12/2025.
20/03/2023: Publication reference added.
16/11/2022: Cambridge University Hospitals NHS Foundation Trust, University Hospitals of North Midlands NHS Trust, University Hospitals Plymouth NHS Trust, Northern Care Alliance NHS Foundation Trust, Hull University Teaching Hospitals NHS Trust, Sheffield Teaching Hospitals NHS Foundation Trust, South Tees Hospitals NHS Foundation Trust, University Hospitals Sussex NHS Foundation Trust, Nottingham University Hospitals NHS Trust - Queen's Medical Centre Campus, The Walton Centre NHS Foundation Trust and Oxford University Hospitals NHS Foundation Trust were added as trial participating centres.
18/08/2022: The following changes have been made:
1. The recruitment end date has been changed from 01/08/2022 to 31/07/2024.
2. The overall trial end date has been changed from 31/07/2023 to 31/07/2034 and the plain English summary updated accordingly.
3. The intention to publish date has been changed from 01/08/2023 to 01/08/2024.
4. The scientific title has been changed from "Risk of Aneurysm Rupture (ROAR) Study" to "A UK multicentre long-term longitudinal study of unruptured intracranial aneurysms: the Risk of Aneurysm Rupture (ROAR) Study".
5. A scientific contact has been added.
19/04/2021: Trial's existence confirmed by the Health Research Authority.