Midazolam is a drug that doctors have used for many years to help patients relax before surgery. It makes people feel calm and sleepy. Often, people who receive this medicine don’t even remember the surgery. It’s considered safe and very helpful for many patients.
However, new research from the University of Colorado Anschutz Medical Campus shows that this drug might not be equally safe at all times of the day. The scientists found something surprising—midazolam may be riskier for the heart when it is used at night.
The researchers studied more than 1.7 million medical records. These records included patients who were given midazolam during surgery. Out of all these patients, over 16,000 had heart injuries during or after surgery.
When the scientists looked more closely, they noticed a pattern: heart injuries were more common during nighttime surgeries. This was even more surprising because many of these patients were otherwise healthy.
To understand why this happens, the research team studied how the drug interacts with a gene called PER2. This gene is part of the body’s natural clock, also called the circadian rhythm. This clock controls when we feel sleepy, when we wake up, and many other body functions, including how the heart works.
Midazolam works by increasing a calming chemical in the brain called GABA. But in the experiments, the scientists found that giving the drug at night reduces the activity of the PER2 gene. That’s a problem because the PER2 gene helps protect the heart. So, when the gene is less active at night, the heart is more likely to get damaged.
The researchers tested this idea in mice and confirmed that the gene was less active at night when midazolam was used. This helps explain why people might be at higher risk for heart problems when they get this drug during nighttime surgeries.
This study reminds us that timing can make a big difference when it comes to medicine. Some drugs, like those for high blood pressure, already work better when taken at certain times of day. Now, it seems that midazolam might be more dangerous if it’s given at night.
Dr. Tobias Eckle, the lead scientist in the study, says that doctors should start thinking more about the best time to give medicines, not just which medicine to give. This idea is part of what’s called personalized medicine. It means doctors try to choose the best treatment for each person, and also choose the best time to give it.
The study shows how closely our body’s internal clock is connected to how medicines work. By paying more attention to timing, doctors may be able to keep patients safer and improve medical care for everyone.
If you care about heart health, please read studies about top 10 foods for a healthy heart, and how to eat right for heart rhythm disorders.
For more health information, please see recent studies about how to eat your way to cleaner arteries, and salt and heart health: does less really mean more?
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