A recent study has raised new questions about a medicine that millions of people take to control high blood pressure.
Researchers from the European Sudden Cardiac Arrest Network found that one commonly used drug may be linked to a higher risk of sudden cardiac arrest.
The findings suggest that doctors and patients should pay close attention to the dose of this medicine while more research is carried out.
Sudden cardiac arrest is a medical emergency that happens when the heart suddenly stops beating. Unlike a heart attack, which is caused by blocked blood flow to the heart, sudden cardiac arrest is usually caused by a problem with the heart’s electrical system.
When the heart stops pumping blood, a person quickly loses consciousness and stops breathing normally. Without immediate treatment, death can happen within minutes.
Sudden cardiac arrest is a major health problem around the world. In Europe, it causes about half of all deaths related to heart disease and around one in five natural deaths. Because it often happens suddenly and outside hospitals, it has been difficult for scientists to study.
The researchers focused on two common blood pressure medicines called nifedipine and amlodipine. Both belong to a group of medicines known as calcium channel blockers. They lower blood pressure by relaxing blood vessels, making it easier for blood to flow and reducing the workload on the heart. Doctors also prescribe them to treat chest pain, known as angina.
The research team examined medical records from thousands of patients. They compared people who had experienced sudden cardiac arrest with similar people who had not. They also looked carefully at the type of medicine each person was taking and the dose they received.
The results showed that people taking high doses of nifedipine had a higher risk of sudden cardiac arrest. The same increase was not seen in people taking amlodipine. This finding surprised the researchers because both medicines have been used for many years, and earlier studies had not clearly shown this difference.
The scientists believe this possible link may have gone unnoticed because sudden cardiac arrest is difficult to investigate. It happens very quickly, often without warning, making it hard to collect detailed information. By studying large groups of patients, the researchers were able to identify a pattern that smaller studies may have missed.
The researchers said people taking high doses of nifedipine should be aware of symptoms such as chest pain, shortness of breath, dizziness, or feeling generally unwell. These symptoms do not always mean sudden cardiac arrest is about to happen, but they should be discussed with a doctor as soon as possible.
The findings do not mean people should stop taking nifedipine. The medicine remains an effective treatment for many patients with high blood pressure and angina.
Anyone who has concerns should continue taking their medication and speak with their doctor before making any changes. Doctors may decide that a lower dose or a different medicine, such as amlodipine, is more suitable for some patients.
The study was published by the European Sudden Cardiac Arrest Network. The researchers say more studies are needed to confirm the results and identify which patients may face the greatest risk. The findings remind us that even medicines that have been used safely for many years should continue to be carefully studied so treatments can become even safer.
If you care about high blood pressure, please read studies that early time-restricted eating could help improve blood pressure, and natural coconut sugar could help reduce blood pressure and artery stiffness.
For more information about blood pressure, please see recent studies about added sugar in your diet linked to higher blood pressure, and results showing vitamin D could improve blood pressure in people with diabetes.
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