A recent study from the University of Colorado Anschutz Medical Campus suggests that the widely used sedative midazolam may increase the risk of heart damage when given at night during surgery.
This finding adds to growing evidence that the timing of medications can influence their effects on the body.
Midazolam is a sedative often given before surgery to induce drowsiness, relieve anxiety, and help patients forget parts of the procedure. While generally considered safe, this study suggests that its effects may vary depending on when it is administered.
Researchers analyzed a large dataset from the Multicenter Perioperative Outcomes Group, which included 1,773,118 surgical cases involving midazolam across 951,345 patients. Among them, 16,404 individuals developed myocardial injury (heart damage). While the drug did not increase heart risk overall, the timing of administration played a crucial role.
The study found that midazolam was linked to a higher risk of heart injury in non-cardiac surgeries when given at night, particularly in otherwise healthy patients. This discovery is significant because it could impact patient survival rates and surgical outcomes.
Scientists are still investigating why nighttime administration of midazolam increases heart risk. One possible explanation involves the PER2 gene, which helps protect the heart and follows the body’s natural circadian rhythm.
Studies in mice suggest that midazolam disrupts the circadian system by increasing GABA, a neurotransmitter that calms brain activity. This may reduce PER2 levels at night, making the heart more vulnerable to damage.
The findings highlight the importance of considering the best time of day for administering medications. Some drugs, such as blood pressure medications, are known to be more effective when taken at night. The researchers suggest that new drugs should be tested for their optimal timing to maximize benefits and minimize risks.
The study, led by Tobias Eckle, was published in Frontiers of Cardiovascular Medicine.
If you care about heart health, please read studies about how eating eggs can help reduce heart disease risk, and herbal supplements could harm your heart rhythm.
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