Are people with certain medical conditions more likely to develop pulmonary embolism?
Pulmonary embolism is a serious medical condition that occurs when a blood clot blocks a blood vessel in the lung. While anyone can develop a blood clot, individuals with specific medical conditions are statistically more likely to experience these events due to changes in blood chemistry, circulation, or physical mobility. Understanding which health conditions contribute to this risk is vital for effective prevention and ensuring that those at higher risk receive appropriate medical monitoring and support from healthcare professionals.
People with certain medical conditions, such as cancer, heart disease, or inflammatory disorders, have a significantly increased risk of developing a pulmonary embolism. These conditions can alter the way blood clots or slow down the flow of blood through the veins, making it easier for a blockage to form. This article provides a factual overview of the health conditions linked to an increased risk of lung clots and explains how UK medical guidance helps manage these risks through preventative care.
What We’ll Discuss in This Article
- The impact of cancer and its treatments on blood clotting risks.
- How heart and lung diseases affect circulation and increase clot probability.
- The link between inflammatory conditions and venous thromboembolism.
- The role of inherited blood disorders in recurrent pulmonary embolism.
- How temporary medical situations, such as surgery, intersect with chronic health.
- Preventative strategies used by the NHS for high risk patient groups.
The link between cancer and pulmonary embolism
Cancer is one of the most significant medical conditions that increases the risk of pulmonary embolism because it can cause inflammation and release chemicals that make the blood more likely to clot. The NHS notes that people with cancer are at a higher risk of blood clots, particularly during certain treatments like chemotherapy or after major surgery. This risk varies depending on the type of cancer and its stage, with some cancers having a more profound effect on the blood’s natural balance than others.
Heart and lung diseases as risk factors
Chronic heart and lung conditions can increase the risk of pulmonary embolism by slowing down the movement of blood through the body or causing damage to the blood vessels. Heart failure, for example, reduces the heart’s ability to pump blood efficiently, which can lead to blood pooling in the legs and forming a deep vein thrombosis. Similarly, chronic obstructive pulmonary disease (COPD) can cause low oxygen levels and inflammation, both of which are factors that can trigger the body’s clotting mechanisms more frequently than in healthy individuals.
Chronic inflammatory conditions and clotting
Long term inflammatory conditions, such as rheumatoid arthritis, Crohn’s disease, or vasculitis, are associated with a higher risk of pulmonary embolism because chronic inflammation can activate the clotting system. When the body is in a state of persistent inflammation, the lining of the blood vessels can become damaged, and the blood becomes “stickier.” Healthcare professionals monitor patients with these autoimmune and inflammatory disorders closely, especially during periods when their condition is particularly active or during flare ups.
Inherited blood clotting disorders
Some individuals are born with genetic conditions, known as thrombophilias, which make their blood clot more easily than normal. Conditions such as Factor V Leiden or protein C and S deficiencies mean that the body’s natural anticoagulation system does not work as effectively as it should. NICE clinical guidelines recommend that people with unprovoked pulmonary embolism should be assessed for underlying risk factors, which may include testing for inherited clotting disorders in specific circumstances. These conditions often require life long medical management to prevent recurrent embolisms.
| Medical Condition | Primary Reason for Increased Risk | Common Management Strategy |
| Active Cancer | Release of pro-clotting factors by tumours. | Prophylactic blood thinners during treatment. |
| Heart Failure | Slower blood circulation and venous pooling. | Monitoring and encouragement of gentle mobility. |
| Thrombophilia | Genetic predisposition to blood clotting. | Long term or lifelong anticoagulant medication. |
| Inflammatory Bowel Disease | Systemic inflammation affecting blood vessels. | Vigilance during flare ups and hospitalisations. |
Surgery and periods of immobility
While not a chronic disease, undergoing major surgery or being hospitalised for a serious illness significantly increases the risk of a pulmonary embolism. Surgery can cause direct damage to blood vessels, and the subsequent period of bed rest prevents the leg muscles from helping to pump blood back to the heart. In the UK, every patient admitted to hospital undergoes a risk assessment to determine if they need preventative treatment, such as compression stockings or blood thinning injections, to mitigate this temporary but high risk period.
Pregnancy and hormonal conditions
Pregnancy and certain hormonal conditions also increase the risk of pulmonary embolism because of changes in blood chemistry and physical pressure on the veins. High levels of oestrogen, whether from pregnancy, hormone replacement therapy, or certain types of contraception, can increase the production of clotting factors. During pregnancy, the growing uterus can also physically obstruct the veins in the pelvis, slowing down blood return from the legs and increasing the likelihood of a deep vein thrombosis forming.
Conclusion
A wide range of medical conditions can make an individual more likely to develop a pulmonary embolism by affecting the blood’s consistency or circulation. Conditions such as cancer, heart disease, and genetic clotting disorders require careful medical supervision and, in many cases, preventative treatment to reduce these risks. Being aware of your personal health history and discussing your risk factors with a clinician is the best way to prevent a serious clotting event. If you experience severe, sudden, or worsening symptoms, call 999 immediately.
Why does cancer make my blood clot more easily?
Cancer cells can release substances that trigger the clotting process, and the inflammation caused by the disease also makes blood vessels more prone to clot formation.
Do all people with heart failure get blood clots?
No, while the risk is higher because of slower blood flow, many people with heart failure do not develop clots, especially if they stay mobile and follow their treatment plan.
Can my family history tell me if I am at risk?
Yes, if multiple family members have had blood clots, you may have an inherited condition like thrombophilia, which you should discuss with your GP.
Are these risks permanent for people with chronic conditions?
For some conditions like heart disease or genetic disorders, the risk may be ongoing, while for others like cancer, the risk may decrease once the disease is in remission.
How does inflammation in my joints affect the blood in my lungs?
Systemic inflammation affects the entire body, including the blood vessels and the chemicals that regulate clotting, not just the area where you feel pain.
What should I do if I have one of these conditions and have to travel?
If you have a high risk condition, you should take extra precautions during long journeys, such as staying hydrated, moving your legs, and potentially wearing compression stockings.
Can medication for other conditions increase my risk?
Certain medications, particularly those containing hormones like the combined pill or HRT, can increase clotting risks, and your doctor will consider this when prescribing them.
Authority Snapshot (E-E-A-T Block)
This guide was produced by the MyPatientAdvice Medical Content Team and reviewed by Dr. Stefan Petrov to provide accurate, evidence-based information for the public. The content is strictly aligned with the clinical standards and risk assessment protocols established by the NHS and NICE for venous thromboembolism. Our goal is to educate the public on the various health factors that influence blood clot risk and the importance of clinical monitoring in the UK.
