Beta-blockers can enhance survival and quality of life in persons with coronary heart disease, whereas aspirin and other antiplatelet drugs can reduce the chance of a heart attack.
However, during hot weather events, when heart attacks are more frequent, those protections can backfire. According to a recent study, a disproportionate number of those who experience non-fatal heart attacks linked to hot weather are taking these heart medications.
During heat waves, Patients who are “taking these two medications”, according to first author of the study Kai Chai “have higher risk” and “they should really take precautions.”
These safety measures include cooling techniques like turning on the air conditioner or going to a public cooling facility.
Heart attacks can be caused by external environmental factors like cold temperatures and air pollution. There is mounting evidence that hot weather can also cause this. However, epidemiologists are currently trying to determine which populations are most susceptible to these climatic extremes.
In this study, using a registry, the team examined 2,494 incidents of non-fatal heart attacks in Augsburg, Germany between 2001 and 2014 during the hot-weather months (May through September).
Previous studies had showed that exposure to either heat or cold increased the likelihood of heart attacks, and they projected that heat-related heart-attack rates would climb if the world warmed by 2 to 3 degrees Celsius.
The present study expanded on that research by looking at individuals’ medication use prior to having a heart attack.
By comparing heat exposure on the day of the heart attack to the same days of the week within the same month, they conducted an analysis of the data that allowed patients to act as their own controls. In other words, the authors compared a person’s exposure to temperature on a heart attack day to their exposure to temperature on other, “control” June third Thursdays.
Two drugs associated with risk
It was discovered that beta-blocker or antiplatelet drug users were more likely to experience a heart attack on the hottest days compared to control days. Beta-blocker use was linked to a 65 percent increase in risk, while antiplatelet drug use was linked to a 63 percent increase in risk. A 75 percent increased risk applied to those using both medicines. On hot days, heart attacks were not more likely to occur in non-users of those drugs.
The study does not establish either that these drugs increased the risk of heart attacks or that they were the direct cause of the heart attacks. It’s plausible that they did raise the risk of heart attacks brought on by hot weather, but it’s also possible that patients’ underlying heart conditions account for both the prescriptions and the increased risk of heart attacks in hot weather.
Nonetheless, one indicator suggests that the drugs may be to fault.
When researchers compared younger patients (25 to 59 years old) to older patients (60 to 74 years old), they discovered that the younger group was healthier, with reduced incidences of coronary heart disease. Although older patients had more cardiac disease, younger patients taking beta-blockers and antiplatelet medicines were more vulnerable to heat-related heart attacks than older patients.
Another indication that these two types of medications may make patients more vulnerable: Other heart drugs, for the most part, did not appear to be associated with heat-related heart attacks. The statins were an exception. Statins were linked to a more than threefold increase in the risk of a heart attack on hot days when used by younger persons.)
According to Chen, several drugs may make it difficult to control body temperature. He intends to make an effort to clarify these connections in next research.
The findings imply that some patients with cardiovascular illness may be more at risk for heart attacks as climate change intensifies.
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