Air Travel And Stroke Risk: What's The Connection?

Flying can increase the risk of certain types of strokes, especially for those with specific medical conditions. Long-haul flights can elevate the risk of blood clots, which may travel to the brain and cause a stroke. However, the incidence of strokes occurring during flights is low, and there are precautions that can be taken to reduce the risk.

Flying and blood clot risk

Flying can increase the risk of blood clots, which can lead to a stroke. This is due to several factors, including decreased cabin pressure, reduced oxygen levels, and inactivity during long flights.

Cabin Pressure and Oxygen Levels

The air pressure inside an aeroplane is much lower than at ground level, resulting in less oxygen in the bloodstream. This reduction in oxygen levels can increase the risk of stroke, especially for those with pre-existing conditions such as breathing difficulties or a heart condition.

Inactivity and Blood Clots

Sitting still for long periods during flights can lead to blood clots forming in the legs, known as deep vein thrombosis (DVT). These blood clots can then travel to the lungs or brain, causing a pulmonary embolism or stroke, respectively. The risk of developing blood clots during and after air travel is well-documented in several research studies, with long flights increasing clot risk by up to 26%.

Pre-existing Conditions

Certain pre-existing medical conditions can further increase the risk of blood clots during air travel. These include recent surgery, cancer, previous blood clots, pregnancy, and immobility lasting longer than three days. Additionally, up to 30% of the population has a heart deformity called patent foramen ovale, which is an opening between two chambers of the heart. This abnormality can increase the risk of stroke during long-distance flights.

Mitigating the Risk of Blood Clots

To reduce the risk of blood clots during air travel, it is recommended to take regular walks up and down the aisle, perform in-seat exercises (such as moving ankles and legs), maintain proper hydration, and avoid alcohol consumption. Compression stockings are also recommended as they improve circulation and prevent blood clots.

While the overall incidence of stroke during flights is low, it is important for individuals with pre-existing conditions or risk factors to carefully consider the potential risks and take the necessary precautions when flying.

Low incidence of stroke on flights

While flying can increase the risk of certain types of strokes, the incidence of strokes during flights is low.

An Australian group of medical researchers defined strokes related to air travel as any stroke occurring within 14 days of travel. After tracking 131 million passengers at Melbourne airport between 2003 and 2014, they reported that stroke-related air travel occurs in less than one in a million passengers. This suggests that there may not be a significantly increased risk of stroke from flying.

Another group of researchers from Spain found that a stroke occurred at a rate of one per 35,000 flights. Over 70% of those who had a stroke on an airplane had carotid artery stenosis, a narrowing of a blood vessel in the neck, which is a risk factor for stroke.

Despite the low incidence of strokes on flights, it is important to consider the risks associated with flying after a stroke. These include hypercoagulability (excessive blood clotting), reduced oxygen levels, and delayed medical treatment.

To reduce the risk of blood clots, it is recommended to get up and move around during the flight, perform leg exercises while seated, stay hydrated, and avoid alcohol. The general advice is that if you can walk 50 meters without getting breathless or climb one flight of stairs without getting breathless, you will be able to tolerate the lower oxygen levels on a flight.

It is also important to consult with a doctor before flying after a stroke, as they can determine if you are medically stable enough for air travel.

Stroke risk factors

Strokes are caused by blocked blood flow to the brain or sudden bleeding in the brain. While anyone can have a stroke at any age, certain factors can increase your chances of having one. These factors can be divided into two main categories: those that are within your control, and those that are not.

Risk Factors Beyond Your Control

• Age: The older you are, the more likely you are to have a stroke. The chance of having a stroke doubles every ten years after the age of 55. However, it's important to note that many people younger than 65 also experience strokes.
• Genetics and family history: Your risk of having a stroke is higher if a parent or other family member has had one, especially at a younger age.
• Sex: Men are more likely to have a stroke at younger ages, but since women tend to live longer, their lifetime risk of having a stroke is higher.
• Race and ethnicity: In the United States, stroke occurs more frequently in Black, Alaska Native, American Indian, and Hispanic adults compared to white adults.

Risk Factors Within Your Control

• High blood pressure: High blood pressure is a leading cause of stroke. It can be managed through lifestyle changes or medication.
• Cholesterol: High cholesterol levels can lead to a buildup in the arteries, including those in the brain, increasing the risk of a stroke.
• Heart disorders: Common heart conditions such as coronary artery disease, heart valve defects, irregular heartbeat, and enlarged heart chambers can increase the risk of blood clots, which may lead to a stroke.
• Diabetes: Diabetes can cause a buildup of sugars in the blood, preventing oxygen and nutrients from reaching the brain. It is also associated with high blood pressure, another risk factor for stroke.
• Obesity: Obesity is linked to higher levels of "bad" cholesterol and lower levels of "good" cholesterol. It is also a risk factor for high blood pressure and diabetes, which are both associated with an increased risk of stroke.
• Lifestyle choices: Unhealthy lifestyle choices, such as consuming a diet high in saturated fats, trans fat, and cholesterol, or engaging in excessive alcohol consumption, can increase the risk of stroke. Lack of physical activity, tobacco use, and exposure to secondhand smoke are also contributing factors.
• Social determinants: The cumulative effect of social factors, such as living in a poor or rural area, having low education or income, and lacking access to quality healthcare, can significantly impact stroke risk.

Recovery and flying

If you've recently had a stroke, it's understandable to be concerned about the risks of flying. While it's important to be cautious, the good news is that, generally, flying is safe for stroke survivors. Here are some essential things to keep in mind as you plan your travel:

Wait at Least Two Weeks:

It's recommended to wait for at least two weeks after a stroke before flying. The symptoms are typically most intense during the first two weeks, and new symptoms may arise, so it's best to avoid air travel during this period. This waiting period is crucial to ensure your safety and well-being.

Consult Your Doctor:

Before planning your trip, have an open discussion with your doctor about your individual healthcare needs. They can assess your medical stability and determine if it's safe for you to fly. It's important to get their clearance before booking your travel.

Understand the Risks:

Flying does come with some risks that are important to be aware of. These include:

• Hypercoagulability (Excessive Blood Clotting): Long flights can increase the risk of blood clot formation, which is a leading cause of ischemic stroke. Deep vein thrombosis (DVT) can occur due to inactivity in cramped spaces, and these clots can travel to the lungs or brain, leading to serious health issues.
• Reduced Oxygen Levels: Airplane cabins have lower oxygen levels than the ground environment. If a stroke has left you with heart or breathing problems, this reduced oxygen level can be a concern. Supplemental oxygen may be necessary during the flight.
• Delayed Medical Treatment: In the event of a stroke on a plane, emergency medical attention may be delayed. Some stroke interventions, such as tissue plasminogen activator (TPA), require prompt administration, which might not be possible during a flight.

Take Precautions:

To mitigate the risks mentioned above, consider the following precautions:

• Contact the airline in advance: Inform them of any mobility issues or special assistance you may need. Many airlines offer services like vision and hearing assistance, wheelchair service, and medical device transport.
• Travel with a companion: Having someone accompany you on the trip can provide peace of mind and assistance if needed.
• Get travel insurance: Protect your trip financially and ensure you understand your health coverage at your destination. Medical care abroad can be costly, so know your insurance coverage limits.
• Allow extra time at the airport: Give yourself sufficient time to navigate security, rest, and reach your gate without added stress.
• Keep medication accessible: Always carry your medication in your hand luggage, and ensure you have enough for your entire trip. Don't forget to bring any necessary medical documentation as well.
• Wear compression socks: Compression garments improve circulation and help prevent blood clots from forming in your legs.
• Stay active during the flight: Get up and walk around the cabin when possible. If you can't walk, perform leg exercises like ankle pumps and knee extensions while seated. Movement is key to preventing blood clots.
• Stay hydrated and avoid alcohol: Drink plenty of water and avoid alcoholic beverages, as they can dehydrate you and increase the risk of clot formation.
• Be mindful of your diet: What you eat and drink can impact your blood pressure, a crucial factor in stroke risk. Avoid excessive salty snacks and stay hydrated to maintain healthy blood pressure levels.

Remember, every stroke is unique, and your doctor's advice should always come first. Waiting 1-3 months after a stroke before travelling is generally recommended, especially if you have residual symptoms or medical complications. This waiting period allows you to receive the necessary medical care and rehabilitation to improve your chances of a complete recovery.

Precautions for flying after a stroke

Flying after a stroke is a common concern for many stroke survivors. While it is generally safe to fly after a stroke, there are some precautions you should take to ensure a safe and comfortable journey. Here are some essential instructions to follow:

• Wait at least two weeks after a stroke before flying: It is recommended to wait for a minimum of two weeks after experiencing a stroke before considering flying. Symptoms are typically most severe during the initial two weeks following a stroke, and new symptoms may emerge, making it prudent to avoid air travel during this period.
• Consult your doctor: Discuss your travel plans with your doctor, as they are most familiar with your health status and can provide personalised advice. They can assess your medical stability and determine if you are ready for air travel.
• Be mindful of your health condition: If you have had brain surgery around the time of your stroke, it is advisable to wait at least a week after the procedure before flying. Air trapped in the head during surgery can expand in the low-pressure airplane cabin, leading to serious complications. Additionally, consider the impact of your stroke on your mobility, comfort, and ability to manage air travel.
• Address oxygen requirements: Airplane cabins have lower oxygen levels than the typical environment. If your stroke has left you with heart or breathing problems, carefully consider this aspect before flying. If you require supplemental oxygen, ensure you have a Department of Transportation-approved battery-powered portable oxygen concentrator onboard.
• Prevent deep vein thrombosis (DVT): Long periods of immobility during air travel can increase the risk of developing blood clots in the legs, known as deep vein thrombosis (DVT). These clots can dislodge and travel to the lungs or, if you have a patent foramen ovale (a small hole in the heart), to the brain, causing a stroke. To prevent DVT:
• Move around: Get up and walk around the cabin when possible. If you are unable to walk, perform manual exercises for your arms and legs, such as flexing your ankles, to promote blood flow.
• Stay hydrated: Drink plenty of water and avoid alcohol, which can lead to dehydration.
• Wear compression stockings: Elastic compression stockings can help reduce the risk of DVT by improving circulation in your legs.
• Plan ahead: Contact the airline at least two days in advance to inform them of any mobility issues or special assistance you may require. Keep extra medication in your carry-on luggage to avoid delays or complications due to lost baggage. Research the medical facilities at your destination, and ensure your health insurance covers you while travelling.
• Travel with a companion: Consider travelling with a family member or friend who can provide assistance and support throughout your journey. Inform them of your medical history, requirements, and how to respond in an emergency.
• Allow extra time: A stroke can impact your mobility and cognitive functions, so allow ample time to navigate the airport, check-in, and board the plane to reduce stress and anxiety.
• Limit salty and fried foods: Consuming salty or fried foods while travelling can increase blood pressure and cause fluid retention, so it is advisable to limit these types of snacks.
• Arrange special assistance: Contact the airline in advance to request any necessary assistance, such as vision or hearing assistance, wheelchair services, or assistance with mobility and medical device transport. Airports also have assistance points where you can seek help with transportation if your mobility is limited.
• Get travel insurance: Protect your trip by purchasing travel insurance, especially if you anticipate the need for refunds or rescheduling. Additionally, ensure you understand how your health coverage will apply at your destination, as medical care abroad can be costly.

By following these precautions, you can help ensure a safe and comfortable flying experience after experiencing a stroke.

Frequently asked questions