Midazolam is a medicine often used in hospitals to help patients relax or fall asleep before surgery. It is known for working quickly and for causing memory loss, so many people do not remember the operation afterward.
Doctors have relied on it for years because it is effective and generally considered safe. However, a new study suggests that when midazolam is given at night, it may carry a hidden risk for the heart.
Researchers at the University of Colorado Anschutz Medical Campus examined more than 1.7 million medical records from patients who received midazolam before surgery. Among these patients, more than 16,000 later showed signs of heart injury.
When the scientists analyzed the data more closely, they noticed something unusual. The risk of heart injury was higher in surgeries performed at night compared with those done during the day, especially among patients who were otherwise healthy.
This discovery led the researchers to explore why the time of day might matter so much. They focused on a gene called PER2. This gene plays an important role in protecting the heart from damage.
It is also part of the body’s circadian rhythm, which is the internal clock that controls sleep, hormones, body temperature, and many other daily processes. The circadian rhythm is strongly influenced by light and darkness, helping the body adjust to day and night.
To understand the connection, scientists conducted experiments using mice. They found that midazolam may lower the activity of the PER2 gene at night.
This is concerning because PER2 is especially important for protecting heart tissue from stress. At night, the natural level of this protective gene is already lower. If midazolam reduces it even more, the heart may become more vulnerable to injury.
Midazolam works by increasing the effect of a calming brain chemical called GABA. This slows brain activity, making patients feel relaxed and sleepy. While this effect is helpful for reducing anxiety before surgery, the study suggests it might also interfere with the body’s natural heart protection system during nighttime hours.
The findings highlight a growing area of research known as chronomedicine. This field studies how the timing of treatments affects how well they work and how safe they are.
Scientists have already learned that some medications, including certain blood pressure drugs, may work better when taken at specific times of day. Now, this study suggests that sedatives like midazolam may also need to be timed carefully.
The research was led by Dr. Tobias Eckle and published in Frontiers in Cardiovascular Medicine. It does not mean that midazolam is unsafe for everyone. The drug remains an important tool in modern medicine. Instead, the study suggests that doctors may need to consider the timing of its use, especially for patients undergoing nighttime procedures.
This discovery shows that even small details, such as when a medicine is given, can have a major impact on health. As scientists continue to learn more about the body’s internal clock, future treatments may become safer and more personalized. Paying attention to timing could help protect patients while still allowing them to benefit from effective medications.
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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