A new study published in JAMA has raised important concerns for older adults living with atrial fibrillation, a common heart rhythm disorder also known as AFib.
The research suggests that some patients who take certain blood pressure and heart rate medications alongside blood thinners may face a higher risk of serious bleeding. These findings could influence how doctors manage treatment for millions of people worldwide.
Atrial fibrillation is a condition in which the heart beats in an irregular and often rapid way. This irregular rhythm can cause blood to pool inside the heart, increasing the chance that blood clots will form. If a clot travels to the brain, it can cause a stroke.
Because of this danger, people with AFib are commonly prescribed anticoagulant drugs, also known as blood thinners, to reduce the risk of clot formation. These medicines can be life-saving, but they also increase the risk of bleeding.
In addition to blood thinners, many people with atrial fibrillation also take medications to control their heart rate. Two commonly used drugs for this purpose are diltiazem and metoprolol. While both drugs help slow the heart rate, they work in different ways and are processed differently by the body.
The research team wanted to understand whether combining certain heart rate drugs with blood thinners could increase the risk of harm. To do this, they studied Medicare records from adults aged 65 and older who began treatment between 2012 and 2020.
All participants had atrial fibrillation and were taking newer anticoagulants such as apixaban or rivaroxaban. They were also prescribed either diltiazem or metoprolol to help manage their heart rate.
The results were concerning. Patients who took diltiazem along with their blood thinner were about 20 percent more likely to be hospitalized or die due to serious bleeding compared to those who took metoprolol. This suggests that diltiazem may increase bleeding risk when combined with anticoagulant drugs.
Researchers believe this higher risk may be related to how diltiazem affects the way the body breaks down medications. According to Dr. Eli Zimmerman, a co-author of the study and an associate professor of stroke and vascular neurology, people process drugs differently based on their genetics.
Some medications can slow the breakdown of blood thinners, causing them to stay in the body longer and thin the blood too much. This can make bleeding more likely, especially in older adults.
Interestingly, the study did not find major differences between the two medication groups when it came to strokes or clot-related events.
This means that while both drugs appear similarly effective at preventing clots, one may carry a greater bleeding risk. This creates a difficult balance for doctors, who must weigh the benefits of heart rate control against the danger of bleeding.
The findings are especially important for older adults. As people age, their bodies become more sensitive to medications, and the risk of side effects increases. Older patients are also more likely to take multiple drugs, raising the chance of harmful interactions.
Looking ahead, the research team hopes to better understand why some patients are more affected by these drug interactions than others. One possible approach is closer monitoring of medication levels in the blood.
By measuring how much of a drug is circulating in a patient’s system, doctors may be able to adjust doses or choose safer combinations. This could lead to more personalized treatment plans that reduce risks while still protecting against stroke.
The study also reminds patients and doctors that medication is only one part of managing heart health. Lifestyle factors play an important role as well.
Research has shown that habits such as excessive coffee consumption may raise blood pressure, especially in people who already have hypertension. In contrast, healthier approaches like eating more plant-based foods or limiting eating to earlier hours of the day have been linked to better blood pressure control.
Overall, this research highlights the complexity of treating atrial fibrillation. While modern medications have greatly reduced the risk of stroke, they can also bring serious side effects when combined in certain ways.
The study underscores the importance of personalized care, careful drug selection, and ongoing monitoring to ensure patients receive the safest and most effective treatment possible.
If you care about heart disease, please read studies that herbal supplements could harm your heart rhythm, and how eating eggs can help reduce heart disease risk.
For more health information, please see recent studies that apple juice could benefit your heart health, and results showing yogurt may help lower the death risks in heart disease.
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