As climate patterns grow increasingly unpredictable, new research suggests that extreme weather may be doing more than disrupting daily life—it could also be putting people’s hearts at risk.

A study published in the American Journal of Preventive Medicine has found a strong link between extreme climate events and a higher incidence of cardiovascular disease. The findings add to growing evidence that climate change is emerging as a significant public health concern.

Led by Linjiang Wei of Xiamen University, the study analyzed data from 157 cities across China between 2015 and 2020. Researchers examined the impact of three types of extreme weather events—intense heat, severe cold, and heavy rainfall—on heart disease risk.

The results point to a clear and concerning pattern. Heatwaves, defined as temperatures of 38°C or higher, were associated with a sharp rise in cardiovascular cases. Each additional day of extreme heat corresponded to more than 1,100 extra cases per 100,000 people, along with a measurable increase in overall risk.

Cold weather also played a role, though to a lesser extent. Days with temperatures dropping to 10°C or below were linked to nearly 400 additional cases per 100,000 people. Meanwhile, extreme rainfall events were found to increase cardiovascular risk as well, particularly among vulnerable populations.

The study’s analysis suggests that each day of extreme heat raises cardiovascular disease risk by over 3%, compared to smaller but still notable increases linked to cold and heavy precipitation.

Certain groups appear to be more at risk than others. Older adults, people with higher body mass index, and those living in areas with high ozone levels were especially vulnerable to cold-related impacts. Meanwhile, the effects of heavy rainfall were more pronounced among rural populations, older individuals, and those nearing retirement age.

Researchers say the findings highlight the broader health implications of climate change. “Climate change is not just an environmental issue; it is a key factor affecting population health,” Wei noted, emphasizing the need for coordinated action across disciplines.

As extreme weather events become more frequent and intense, experts warn that healthcare systems may need to adapt—not only to treat cardiovascular disease, but also to anticipate and mitigate the environmental factors driving it.

The message is becoming increasingly clear: the changing climate is not just altering ecosystems—it is also reshaping the risks to human health, particularly for the heart