Midazolam is a widely used drug that helps patients relax before surgeries. It works quickly to calm nerves and often causes people to forget the experience altogether, making medical procedures less stressful.
However, a new study from the University of Colorado Anschutz Medical Campus has revealed a surprising and important finding: midazolam may carry a higher risk of heart damage if given at night.
Researchers studied more than 1.7 million patient records to explore this issue. Out of all those cases, they identified over 16,000 instances of heart injury following the use of midazolam. When they looked closer, they noticed a clear pattern — heart damage was more likely to happen when surgeries took place at night, even in patients who were otherwise healthy.
This raised an important question: why would the time of day make a difference?
To find out, the research team focused on a gene called PER2, which helps control our body’s internal clock, also known as circadian rhythm. Circadian rhythm is what makes us feel sleepy at night and awake during the day, but it also affects many other body functions, including how well the heart protects itself from stress.
The researchers conducted experiments on mice to better understand how midazolam interacts with the PER2 gene. They found that the drug increases a calming brain chemical called GABA, which helps people feel relaxed.
But there’s a catch — when GABA levels go up, the activity of the PER2 gene goes down, especially at night. That’s a problem because PER2 helps protect the heart from damage. So, when midazolam lowers PER2 activity at night, the heart becomes more vulnerable to injury.
This discovery shows that the time of day a drug is given can affect how it works in the body and how safe it is. In the case of midazolam, giving it at night could increase the chance of heart problems, especially when PER2 levels are already low due to the body’s natural rhythms.
The lead scientist, Tobias Eckle, believes this finding could change how doctors think about drug timing. The research, published in Frontiers in Cardiovascular Medicine, suggests that some drugs might be safer or more effective if given at specific times of day. For example, some blood pressure medications already work better when taken at night.
This study is part of a growing field called chronotherapy, which focuses on giving medications at the best time based on the body’s natural rhythms. It opens the door to more personalized treatments, where doctors could choose not just the right drug and dose, but also the right time to give it.
While midazolam remains a valuable and commonly used sedative, this new research reminds us that even familiar medications can have unexpected effects depending on when they’re used. By paying attention to our body’s internal clock, doctors may be able to improve treatment outcomes and reduce risks.
In the future, we may see more hospitals and clinics adjusting medication schedules to match the body’s timing. This approach could help make surgeries and other treatments safer, leading to better care for everyone.
If you care about heart health, please read studies that vitamin K helps cut heart disease risk by a third, and a year of exercise reversed worrisome heart failure.
For more health information, please see recent studies about supplements that could help prevent heart disease, stroke, and results showing this food ingredient may strongly increase heart disease death risk.
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