People have been aware for centuries that hot weather can be detrimental to our health. Recently, a team of researchers from University of Pennsylvania and Yale University found that hot weather can also influence the effects of the medicine we take. Their research paper, published in the journal BMJ Open, documents a weather-drug interaction, an interaction that occurs “when the weather affects the effects of a medicine, or when medicine affects the health effects of weather”, says Sean Hennessy, a Professor of Epidemiology at the University of Pennsylvania.
The group gathered health care data from adult patients and hypothesized that the survival benefit of potassium might vary by season. To confirm that, they obtained meteorological data and found out that it corresponded to the health care data they had, which allowed them to analyze the survival benefit of potassium as a function of the outdoor temperature.
The group found out that people who take diuretics – drugs that eliminate excessive fluid in your body and are commonly used to treat heart failure – are at a higher risk of suffering from heat-induced illnesses. The reason is that furosemide, a common diuretic, makes you lose potassium. “Another way of losing potassium is through your sweat,” says Hennessy, “and because you sweat more when it’s hot outside, we hypothesized that the survival benefit of potassium would be higher in hot months than in cold months.” The group concluded that increasing potassium administration in diuretic users when the weather turns hot can mitigate the harmful health effects hot weather might have on them.
These results imply that there might be other drugs that also pose a health risk in hot conditions, which is of great importance as climate change heats up the Earth. Hennessy also suggests the importance of real-world solutions such as reminders apps that, based on the weather forecast, could remind “patients and physicians about the importance to take potassium during hot days.”