What is abdominal aortic aneurysm screening?
Abdominal aortic aneurysm (AAA) screening is a way of detecting a dangerous swelling (aneurysm) of the aorta - the main blood vessel that runs from the heart, down through the abdomen to the rest of the body.
This swelling is far more common in men aged over 65 than it is in women and younger men, so men are invited for screening in the year they turn 65.
An AAA usually causes no symptoms, but if it bursts, it’s extremely dangerous and usually fatal. Around 8 out of 10 people with a ruptured AAA either die before they reach hospital or don’t survive surgery.
Screening involves a simple ultrasound scan of your stomach (abdomen), which takes about 10-15 minutes.
If your abdominal aorta is not enlarged, you don’t ever need to be tested again.
If you have a small to medium aneurysm, you'll be regularly monitored to check it doesn’t get dangerously larger.
If you are found to have a large aneurysm, you'll be seen by a vascular surgeon (a specialist in blood vessels) within two weeks. They will advise on whether you would benefit from treatment to reduce the risk of it bursting.
Why have AAA screening?
An AAA is sometimes picked up by chance – for instance, if you’re being tested for another condition.
In general, if you have an AAA, you won’t know. You probably won’t feel any pain or notice anything different.
But if the aneurysm bursts, it’s a medical emergency, and most people either die before they reach hospital or don’t survive surgery.
Screening is a way of detecting an aneurysm early. If a large aneurysm is detected before it bursts it can be treated. Accepting the invitation to screening cuts the risk of dying from an abdominal aortic aneurysm by about half.
The NHS AAA Screening Programme was set up in England in 2009 and has been offered throughout the UK since the end of 2013.
When AAA screening is offered
Men aged over 65 are far more likely to have an AAA than women or younger men – so any man in England registered with a doctor will receive a letter inviting him for screening in the year he turns 65.
What happens during AAA screening?
The screening test for AAA is a simple, pain-free ultrasound scan of the abdomen that usually takes about 10-15 minutes.
The screening technician will ask you to lift up your shirt and then run a small ultrasound scanner on your abdomen, which will allow the thickness of your abdominal aorta to be measured on a monitor.
The technician will tell you the result straight away and your doctor will also be informed.
What happens next depends on the size of your abdominal aorta:
- If it’s normal, you won’t ever be invited for another screening. An aneurysm grows so slowly that you’re unlikely to develop one after the age of 65.
- If you have a small to medium-sized aneurysm, you’ll be invited back for regular scans to check its size.
- If you have a large AAA, you’ll be referred to hospital to be seen by a vascular surgeon within two weeks. You will then be advised about treatment options but, generally, men with a large AAA are advised that the risk of a large aneurysm rupturing is more dangerous than having surgery to repair it.
FAQs on abdominal aortic aneurysm screening
1. Will I be offered abdominal aortic aneurysm (AAA) screening if I live outside England?
AAA screening programmes have been set up in Northern Ireland, Scotland and Wales. Details are available below:
- NI Direct for details of the programme in Northern Ireland
- NHS Inform for details of the programme in Scotland
- Wales Abdominal Aortic Aneurysm Screening Programme
2. What is the scientific evidence to support AAA screening?
The UK National Screening Committee assesses all the research evidence, pilot programmes and economic evaluations before recommending that a new screening programme be introduced.
The committee decided that an AAA screening programme will deliver benefits at a reasonable cost.
It’s estimated that the programme will reduce the death rate from ruptured AAAs among men aged 65 and over by up to 50% and prevent around 2,000 premature deaths a year.
Read more about the research on AAA screening.
3. What happens if I am a man over 65 and haven’t been screened for an AAA?
AAA screening is offered to all men in England during the year they turn 65.
Men who receive a normal result do not need another scan. Men over 65 who haven’t previously been screened can contact their local screening service without going through their doctor.
4. What about women and men under 65?
The programme targets men aged 65 and over because 95% of ruptured aortic aneurysms occur in this group. Men are also six times more likely to have an aneurysm than women.
Ruptured AAAs are less common in women and, on average, occur 10 years later than in men.
There is no evidence to show that inviting women or men who are younger than 65 for screening would deliver major benefits.
However, the risk of developing an aneurysm is higher if you have a close relative – brother, sister or parent – who has or has had one.
This means you can have an ultrasound scan. Speak to your doctor to discuss a referral.
You are advised to request a scan at the age that is five years younger than your brother, sister or parent was diagnosed.
Close relatives of men with an AAA should take the usual health precautions of not smoking, having a cholesterol and blood pressure check, and staying healthy.
5. What are the implications for driving?
doctors can advise people to stop driving, and also whether a health condition must be reported to the Driver and Vehicle Licensing Agency (DVLA).
Motor insurers cannot ask questions about health conditions, and so do not adjust premiums on that basis.
The DVLA policy on AAAs states that:
- the DVLA must be informed if the aneurysm grows to 6cm
- the person's licence will be suspended if their aneurysm grows to 6.5cm
- their licence will be reinstated after their aneurysm has been successfully treated
The policy on bus, coach and lorry drivers states that:
- the DVLA must be informed if they have an aneurysm of any size
- the person's licence will be suspended if their aneurysm grows to 5.5cm
- the person's licence will be reinstated after their aneurysm has been successfully treated
The screening programme refers men to vascular surgeons if their aneurysm reaches 5.5cm.
The DVLA policy does not affect car drivers with small or medium aneurysms (3.0-5.4cm) who are part of the programme's surveillance group.
6. What are the implications for air travel and travel insurance?
The Association of British Insurers (ABI) has been advised that AAAs are no more likely to rupture at altitude than on the ground, and it is not aware of any airlines operating a standing rule about refusing patients with this condition.
The ABI is also unaware of any travel insurance policies that contain a specific exclusion for AAAs as part of their standard wording.
If an applicant for travel insurance declares an AAA, the ABI understands that the medical screening process does not ask the diameter of the aneurysm, because to do so would be to expect a degree of medical knowledge on the part of the patient that they might not have.
Patients are instead asked whether or not they have had definitive treatment, such as surgery, and if so, when. They are also asked if they are on a waiting list for such treatment and if they have any other related cardiovascular diseases.
The ABI suggests that anyone with an AAA should declare the condition during the travel insurance application process, or when it has been diagnosed, if they have an existing travel policy.
Where an applicant declares an AAA, they may be charged an additional premium or have the condition excluded from cover.
When looking for cover, a broker can help. The British Insurance Brokers Association (BIBA) operates a "find a broker" service that can help and can be contacted on 0870 950 1790.
7. Why does the programme need to retain personal information?
Screening is a diagnostic procedure that requires the subject's consent. There is an associated duty of care to record information to provide evidence of what is done, what is found and to share this with appropriate healthcare providers, so any findings can be followed up.
Recording data enables the programme to quality-assure the screening process to ensure that screening, assessment and treatment are effective and timely.
The abdominal scan is only one part of a systematic pathway of care, and it would be irresponsible and potentially negligent to offer a scan without ensuring that the safeguards offered by an assured national system are in place.
The screening programme needs to retain personal data so it knows if and when an individual has received a scan and whether they have declined screening.
It also enables local programmes to keep track of who has, or hasn't, been invited for screening and deal with follow-up inquiries.
Personal information is only available to healthcare professionals involved in an individual man's screening or any subsequent assessment or treatment.
Although the database is a national system, strict data governance means personal details can only be accessed by staff involved directly in an individual's screening process.
If a man is screened and found to have an aneurysm, it will be necessary to share his information with a vascular unit to support further investigation and potential surgery.
At the screening clinic, you will be asked if you give the programme your permission:
- to store and keep information about you and your visit to the screening clinic on the National AAA Screening System, and to use this information to help offer safe and effective screening
- to screen you for an AAA (which involves an ultrasound scan of your abdomen) and to inform you of the result
- if you are found to have an AAA, to share your personal information with a vascular surgeon through the National Vascular Registry (NVR)
- to contact you, asking whether you will allow us to use your personal information for research purposes
Men will only be screened if they give their consent to the first three points above.
8. Could I find out about other health problems as a result of AAA screening?
No, during the ultrasound scan (the screening test), the technician only looks at your aorta specifically to check if you have an AAA.
If you have any concerns about your health, speak to your doctor.
**9. Where can health professionals find out more about the AAA **screening programme?**
Information for health professionals can be found on the AAA screening programme website.
The screening test for abdominal aortic aneurysm (AAA) is a simple, pain-free ultrasound scan of the abdomen that usually takes about 10 minutes.
When you arrive for your appointment, a screening technician will check your details, explain the scan and give you the chance to ask any questions.
You’ll be asked to lie down and lift up or unbutton your shirt. You don’t need to undress.
The technician will put a clear gel on your stomach (abdomen) and then move a small ultrasound scanner over the skin.
The ultrasound scan will display a picture of the abdominal aorta on a monitor, and the technician can then measure its thickness.
Once you’ve been given the chance to wipe the gel from your abdomen and tuck your shirt back in, the technician will tell you the result straight away and your doctor will also be informed.
Occasionally, the technician will not be able to see the aorta clearly. This is not a cause for concern. If this is the case, they will ask you to have another scan, usually on a different day.
When it's offered
The risk of dying from a ruptured abdominal aortic aneurysm (AAA) is greatest in men aged over 65. This is why the NHS AAA Screening Programme offers screening to men aged 65 and over in England.
Men are invited for screening during the year they turn 65 (April 1 to March 31). This means you’ll either be invited when you’re 64 or just after your 65th birthday.
If you’re registered with a doctor, you will receive a letter from the NHS AAA Screening Programme inviting you for an appointment at a local screening clinic, which might be at your own doctor surgery. If you don’t respond to this first invitation, you will be sent a second invitation within six weeks.
Men over 65 who haven’t already been screened can request a scan by contacting their local AAA screening service directly.
Why aren’t women or younger men screened?
Women and younger men are not invited for screening because 95% of ruptured AAAs occur in men aged 65 and over.
Men are six times more likely to have an AAA than women, and the chance of having an aneurysm increases with age.
All the risks and benefits are carefully studied before a new screening programme is introduced. This is to ensure that the benefits of being offered screening outweigh any potential harms.
The UK National Screening Committee reviewed scientific evidence from around the world and concluded that there is not enough evidence of the benefits of offering screening to women over 65 and younger men.
What if my family has a history of AAA?
Your risk of developing an AAA increases if you have a close family member – brother, sister or parent – who has an AAA or died from one.
If you have, speak to your doctor about the possibility of being referred for a scan.
The usual advice is to have a scan when you’re five years younger than your relative was when the AAA was found.
Close relatives of someone with an AAA should take the usual health precautions of not smoking, having a cholesterol and blood pressure check, and staying as healthy as possible.
Why it's offered
If you have an abdominal aortic aneurysm (AAA), you won’t usually know. You probably won’t feel any pain or notice anything different. Screening is a way of detecting an aneurysm early.
An AAA might be picked up by chance while you are being tested for another problem – for example, if you are given a chest scan because of a persistent cough.
If the abdominal aortic artery gets particularly swollen, you might feel a pulsating feeling or pain in your stomach (abdomen) or back pain.
If you don't experience this, you won’t know you have an aneurysm until it bursts, when it becomes an emergency and is usually fatal. More than 8 out of 10 people with a ruptured AAA either die before they reach hospital or don’t survive emergency surgery.
However, if an aneurysm is found before it ruptures it can be treated – usually by surgery. During this procedure, the swollen section of the aorta is either replaced or strengthened with a section of synthetic tubing.
Because men aged over 65 are particularly at risk of developing an aneurysm, the NHS offers men in this age group in England screening in order to find aneurysms early, so they can be checked regularly or treated.
The easiest way to find out if you have an aneurysm is to have a screening test, where an ultrasound scan of your abdomen is taken.
The NHS AAA Screening Programme was introduced after research showed it could halve the number of deaths from burst aneurysms among men aged 65 and over.
Who is at risk of an abdominal aortic aneurysm?
Men are approximately six times more likely to have an abdominal aortic aneurysm than women. The chance of having an aneurysm increases with age.
The risk of having an abdominal aortic aneurysm can also increase if:
- you smoke
- you have high blood pressure
- a brother, sister or parent has, or has had, an abdominal aortic aneurysm
Deciding to be screened
Screening is a choice and all screening involves a balance of potential harms, as well as benefits.
The UK research study, which was set up to find out whether a national AAA screening programme would be worthwhile, has now been running for over 10 years, and shows that it will cut the risk of dying from an AAA by 48% in men over the age of 65.
There is no risk from the scan itself. However, if you find out from the scan that you have a large aneurysm, it could lead to difficult decisions about having surgery, which has its own risks.
Being told you have a life-threatening condition can also cause considerable anxiety.
It’s important to consider all the information carefully, and you will be sent an information leaflet with your screening letter to help you make this decision.
The NHS AAA Screening Programme has also developed an online decision aid to help you decide whether you want to be screened, and there is also a version you can print out.
If you decide you don’t want to be tested, you can phone your local screening service and ask to be removed from its list of men to invite.
Your abdominal aortic aneurysm (AAA) scan will produce one of four possible results: a normal-sized aorta, a small aneurysm, a medium aneurysm, or a large aneurysm.
What happens next depends on the size of your abdominal aorta.
If your scan is normal
If the ultrasound scan shows your abdominal aorta is a normal size (less than 3cm in diameter) this means you don’t have an AAA.
Should this happen, you won’t be invited back for another scan as an AAA grows slowly, and the chances of you developing one after the age of 65 are very small.
If you’re found to have a small or medium AAA
If the scan shows you have a small (3.0-4.4cm) or medium (4.5-5.4cm) aneurysm, you won't need any treatment at this stage.
You will be invited back for regular scans to check the size of the aneurysm, however, in case it gets bigger.
You’ll be invited for a scan every year if you have a small aneurysm, and every three months if you have a medium aneurysm.
Because aneurysms grow so slowly, it’s unlikely men with a small or medium aneurysm will ever need treatment.
You’ll also be given advice on how you can prevent the aneurysm from getting bigger, including:
- stopping smoking
- eating a balanced diet
- ensuring you maintain a healthy weight
- taking regular exercise
- taking medication on the advice of your doctor – for example, to reduce blood pressure
If you are found to have a large AAA
If the scan shows you have an AAA that is 5.5cm or larger, you will be referred to a vascular surgeon (a surgeon who specialises in diseases of the blood vessels), who may recommend an operation.
You should be seen by the surgeon within two weeks of your screening appointment.
The surgeon will discuss treatment options with you, taking into account your general health and fitness, as well as the size of your AAA.
There are two main options for surgery, which are:
- open surgery – where the surgeon cuts into your stomach (abdomen) to reach the abdominal aorta and replace the enlarged section with a synthetic tube called a graft
- endovascular surgery – a type of "keyhole" surgery where the surgeon makes small cuts in your groin and guides the graft through a leg artery up into the swollen section of aorta to reinforce the wall
If you’re not fit or well enough to undergo surgery, or you don’t want to have surgery, you will be offered lifestyle advice and possibly medication. This can help slow down the growth of an AAA and reduce the risk of a rupture.