Can You Live With an Aneurysm?

Many people live with an aneurysm for years or even a lifetime without it ever causing a problem. Roughly 3% of the general population carries an unruptured brain aneurysm, and an estimated million or more Americans have an abdominal aortic aneurysm they may not know about. The vast majority of these go undetected, and of those that are found, most are monitored rather than operated on. Whether living with an aneurysm is safe depends on its size, location, and a handful of personal risk factors, but the short version is that for most people, the answer is yes.

How Common Are Undiagnosed Aneurysms

Aneurysms are bulges in weakened sections of blood vessel walls. They can form in arteries throughout the body, but the two locations that get the most clinical attention are the brain and the aorta, the large artery running from the heart down through the abdomen. The reason they matter is that a rupture can be catastrophic, but the reason most people never know they have one is that unruptured aneurysms rarely produce symptoms.

For brain aneurysms, population studies put the prevalence at about 2% to 3% in adults without specific risk factors. A systematic review of screening studies found a prevalence of about 2.3% in people with no known predisposition, with rates climbing in older age groups.¹ A more recent review pegged the overall figure at approximately 3%, with higher rates in people who have conditions like polycystic kidney disease or a strong family history of aneurysms.² A large brain MRI study of the general population found cerebral aneurysms in about 1.8% of participants, making them the most common incidental brain finding apart from small strokes.³

For aortic aneurysms, the numbers depend heavily on age and sex. A meta-analysis of population-based screening studies found that prevalence in men aged 60 and older ranged from about 4% to 14%, while in women the range was roughly 0.4% to 6%.⁴ A recent pilot screening study of people over 50 found aneurysms in about 8% of men and 1.3% of women.⁵ One modeling study estimated there may be over a million people in the United States currently living with an abdominal aortic aneurysm.⁶ Most of these people have no idea.

What Makes an Aneurysm Dangerous

The risk that an aneurysm will actually rupture varies enormously. Size is the single biggest factor. A small brain aneurysm under about 7 millimeters in a person without other risk factors has a very low chance of bursting. A pooled analysis of six large studies used to develop the PHASES prediction score estimated that a small aneurysm on the internal carotid artery in a person under 70 without hypertension or prior bleeding carried roughly a 0.25% chance of rupture over five years.⁷ At the other extreme, a large aneurysm over 20 millimeters on a posterior artery in an older person with high blood pressure and a history of prior bleeding could carry a five-year rupture risk above 15%.

Location matters too. Brain aneurysms on arteries at the back of the brain tend to be more dangerous than those in the front. For aortic aneurysms, both the thoracic and abdominal segments can develop bulges, but they differ in their underlying biology and the risk profiles are distinct.⁸ Geography also plays a role in brain aneurysm risk that researchers have not fully explained: Finnish and Japanese populations appear to have substantially higher rupture rates than people in North America and most of Europe.⁷

One important caveat about the PHASES score: it was built on data from patients who were already being monitored, meaning the very highest-risk aneurysms had already been treated. A retrospective study of patients who actually suffered a brain bleed found that nearly 80% of them would have been classified as having less than a 2% five-year rupture risk by the PHASES score before their aneurysm burst.⁹ That doesn’t mean the score is useless, but it highlights that risk prediction remains imperfect and that a “low risk” label is not the same as “no risk.”

Surveillance Instead of Surgery

When a small aneurysm is discovered, the most common approach is to watch it rather than fix it immediately. The reasoning is straightforward: the risks of an operation may outweigh the risk of rupture for a small, stable bulge. Treatment itself carries real chances of complications, so doctors want to be confident the aneurysm is actually dangerous enough to justify intervention.

For brain aneurysms, most specialists recommend periodic imaging to check whether the bulge is growing. A survey of neuroradiologists found that about three-quarters recommended routine imaging surveillance for conservatively managed unruptured aneurysms, with 84% suggesting scans at least once a year. About 59% favored continuing that surveillance for life.¹⁰ A systematic review and meta-analysis of over 8,400 aneurysms confirmed that small unruptured brain aneurysms have low growth and rupture rates, and very small ones carry almost no rupture risk. People with multiple aneurysms or those located on posterior arteries need more frequent monitoring.¹¹

For aortic aneurysms, the surveillance schedule depends on size. Guidelines from vascular surgery societies recommend ultrasound every three years for aneurysms in the 3 to 4 centimeter range and yearly scans for those between 4 and 5 centimeters, based on the low rate of events in small aneurysms.¹² Ultrasound is painless and inexpensive, so this watchful-waiting phase is not especially burdensome from a medical standpoint.

When Treatment Becomes Necessary

Treatment is typically considered when an aneurysm reaches a certain size, is growing quickly, or starts causing symptoms. The size thresholds are not as fixed as people sometimes assume. For abdominal aortic aneurysms, conventional guidelines have used about 5.5 centimeters as the trigger for repair in men. But a modeling study found that for an average-health 60-year-old man, the optimal repair size to minimize death from the aneurysm was actually closer to 6.9 centimeters, and for a 60-year-old woman, about 6.1 centimeters.¹³ This challenges the standard thresholds and suggests that for some patients, waiting longer may actually be the safer bet.

For brain aneurysms, the decision to treat involves weighing the aneurysm’s characteristics against the patient’s age, health, and the specific risks of the available procedures. Two main options exist: surgical clipping, where a neurosurgeon places a tiny metal clip at the base of the bulge to seal it off, and endovascular coiling, where a catheter threads through blood vessels to fill the aneurysm with tiny coils that promote clotting inside it. A Cochrane review comparing the two in patients with ruptured aneurysms found that coiling was associated with better outcomes at one year: about 24% of coiled patients had a poor outcome versus 32% of clipped patients.¹⁴ The tradeoff is that coiling has a higher rate of rebleeding over the long term, though improved technology has narrowed that gap in recent years.¹⁵

For aortic aneurysms, the two main options are open surgical repair, which is major abdominal surgery, and endovascular repair, where a stent graft is placed through small incisions in the groin. In a large randomized trial, long-term survival was similar between the two approaches, with no significant difference over 15 years of follow-up.¹⁶ Endovascular repair has fewer surgical complications upfront but tends to need more follow-up procedures down the road.¹⁷ A large Medicare database analysis found that after matching patients for health status, open repair was actually associated with lower long-term mortality and fewer reinterventions.¹⁸ The right choice depends heavily on the patient’s age, fitness, and anatomy.

Lifestyle and the Factors You Can Control

If you are living with a known aneurysm, a few modifiable risk factors deserve serious attention. Smoking is at the top of the list. Current smokers with brain aneurysms are roughly twice as likely to present with a ruptured aneurysm compared to people who have never smoked, and even former smokers carry elevated risk.¹⁹ Interestingly, a meta-analysis found that smoking was not clearly associated with the growth of unruptured brain aneurysms, which suggests that smoking may increase rupture risk through some mechanism other than simply making the bulge bigger, possibly by weakening the vessel wall directly.²⁰ For aortic aneurysms, smoking is one of the strongest risk factors: the odds of having one are roughly 2.4 times higher in smokers than non-smokers.⁴

Blood pressure control is the other big lever. A population-based study tracking patients after brain aneurysm treatment found that for every 10-point increase in systolic blood pressure, the risk of stroke, heart attack, or death rose by about 16%.²¹ The effect was even more pronounced for diastolic pressure. Keeping blood pressure in a healthy range is one of the most meaningful things you can do to reduce the odds of a bad outcome.

Exercise is a common source of anxiety for people with aneurysms, particularly aortic ones. Many patients assume they should avoid physical activity altogether to avoid putting stress on the vessel. A study of adults with thoracic aortic aneurysms found no significant difference in blood pressure spikes during exercise compared to a control group. In fact, people with higher levels of regular moderate activity actually had lower blood pressure readings during exertion.²² Most guidelines still advise avoiding extreme weightlifting or Valsalva-type straining, but moderate exercise appears not only safe but potentially protective.

The Psychological Weight of Knowing

One of the less-discussed aspects of living with an aneurysm is the mental health toll. Being told you have a ticking time bomb in your body, even when doctors assure you it is statistically unlikely to burst, is genuinely stressful. Research confirms what you might expect: people living with unruptured brain aneurysms have reduced quality of life, particularly in mental health domains. One study found that this was true regardless of whether the aneurysm had been treated.²³ In other words, the diagnosis itself leaves a mark that treatment alone does not erase.

A separate study of patients with unruptured aneurysms being managed without intervention found that about a quarter had mild anxiety and another roughly 14% had moderate to severe anxiety symptoms. The tendency toward anxious rather than depressive symptoms was consistent across the group.²⁴ These findings argue for making psychological support a standard part of aneurysm management, not just an afterthought. Patients who understand the actual statistics tend to cope better than those left to imagine the worst.

Pregnancy and Brain Aneurysms

One situation that adds real complexity is pregnancy. The cardiovascular changes that come with carrying a pregnancy, including increased blood volume, higher cardiac output, and hormonal shifts affecting blood vessel walls, can raise the risk of forming, growing, or rupturing a brain aneurysm. The incidence of subarachnoid hemorrhage is elevated in pregnant patients, representing a serious risk to both mother and fetus.²⁵ This does not mean pregnancy is off the table for someone with a known aneurysm, but it does mean the conversation with a neurologist should happen well before conception. The aneurysm’s size, location, and the patient’s overall vascular health all factor into how much additional risk pregnancy adds.

Flying and Altitude

A question that comes up regularly in online patient forums is whether air travel is safe with an unruptured aneurysm. There is surprisingly little direct research, but one useful data point comes from military aviation. A study of 23 active-duty military pilots diagnosed with unruptured brain aneurysms found that 16 were placed under conservative surveillance. All were men with small aneurysms under 5 millimeters and no hypertension or smoking history. Their estimated annual rupture risk was less than 0.5%. Of those 16, 11 were cleared to continue flying with some operational restrictions, and 5 with the lowest-risk aneurysm location received fully unrestricted flight certification.²⁶ Commercial aircraft cabins are pressurized to a level equivalent to about 6,000 to 8,000 feet of altitude, a much milder environment than what military pilots face. For most people with small, stable aneurysms, flying on a commercial airline is considered safe, though it is always worth confirming with your own doctor given your specific situation.

Emerging Tools for Predicting Rupture

One of the frustrations in aneurysm management is that predicting which ones will rupture remains an inexact science. Size and location help, but as the PHASES score limitations show, many ruptures occur in aneurysms that would have been classified as low risk. Researchers are exploring computational fluid dynamics, which uses computer modeling to simulate how blood flows through an individual aneurysm. The idea is that the pattern and force of blood flow hitting the aneurysm wall may matter as much as the wall’s dimensions. Although controversy persists about which flow parameters best predict rupture, this technology is already being used in some centers as an added input for clinical decisions.²⁷

Anti-inflammatory drugs represent another area of active research. Since inflammation in the artery wall plays a role in aneurysm growth and weakening, some researchers have investigated whether common anti-inflammatory medications could slow aneurysm progression. Preclinical evidence suggests that certain drugs in this class can inhibit key inflammatory pathways involved in aneurysm progression.²⁸ This work is still largely in the laboratory and animal-model phase, and no drug has been approved specifically for aneurysm prevention in humans. But it points toward a future where medication rather than surgery could be an option for managing stable aneurysms, which would fundamentally change what “living with an aneurysm” looks like.

Family History and Genetic Screening

If a close relative has had an aneurysm, your risk is higher than average. This is true for both brain and aortic aneurysms, and researchers have identified shared genetic factors that can predispose a person to aneurysms in more than one location.²⁹ For brain aneurysms, screening with MR angiography is sometimes offered to people with two or more first-degree relatives who have had aneurysms, or to those with certain connective tissue disorders. The overall prevalence of brain aneurysms is higher in these familial groups than in the general population.²

For aortic aneurysms, screening recommendations are more established. Many countries offer one-time ultrasound screening for men over 65 who have ever smoked, because that group carries the highest risk. The question of whether to screen more broadly, including younger people and women, is still being debated. The pilot study mentioned earlier, which found aneurysms in over 5% of men as young as 50 to 64, suggests the net may need to be cast wider.⁵ If you have a family history of aortic aneurysms or related conditions like Marfan syndrome or Ehlers-Danlos syndrome, talking to your doctor about screening sooner rather than later is reasonable regardless of current guidelines.