The summer of 2023 was the hottest on record since 1850, and this summer could be just as sweltering. That puts older adults—a group especially vulnerable to heat-related illnesses—at elevated risks for a number of health conditions and outcomes. Older people are less able to regulate changes in body and environmental temperatures, and higher temperatures put them at increased risk of dehydration, heat stroke, blood pressure changes, muscle cramps, and dizziness.
These issues are likely to become far more prevalent than they currently are. From now until 2050, the number of people 60 years or older will double to nearly 2.1 billion, making up 21% of the global population, according to projections from the World Health Organization.
Giacomo Falchetta, a scientist at the Euro-Mediterranean Center on Climate Change in Italy, and his team wanted to better understand the scope of the problem. In a new study published in Nature Communications, they correlated a given population's age with the region's temperatures to project how older people will be affected by hotter weather.
They found that by 2050, more than 23% of the world’s population over age 69 will be living where peak temperatures reach beyond 99.5°F (37.5°C), compared to just 14% of that group today. That means that up to 246 million more elderly people will be exposed to dangerously high temperatures.
“Everywhere around the world, we see increasing life expectancy, which is bringing many more older adults into the health-care system due to climate change,” Falchetta says.
Read More: What's the Best Kind of Sunscreen?
Falchetta and his team used population data from the U.N. Population Division and widely publicized estimates of climate change that predict warming temperatures in coming years. Those data allowed them to tease apart the main factors driving heat exposure for older adults in different parts of the world. In temperate regions including North America and Europe, for example, higher global temperatures will be the primary factor affecting heat exposure for the elderly, while in typically warmer parts of the world such as Asia, Africa, and South America, population growth, and increases in longevity are more likely to contribute to more older adults exposed to heat-related illnesses.
Falchetta hopes the research helps persuade policymakers to address the coming collision of population growth, increased life expectancy, and climate change. Understanding where older populations are at risk for heat-related health issues, for example, could help governments to focus health-care resources and address infrastructure needs, such as building power grids to manage increased electricity demand for air conditioning and cooling centers, and providing more urban green spaces.
“We hope to engage public-health planners, national economic planners, and international organizations such as the World Health Organization and the U.N. Development Programme to provide a sense for what we expect the needs of an aging population will be in a warmer world,” he says.