By Lillian Witting, MPH, CAPM, Manager, Research and Programs 

Summer is often associated with spending more time outdoors. But extreme heat, poor air quality, and severe weather can make everyday summer activities less safe,  especially for people living with chronic conditions and disabilities who may be more susceptible to the health effects of climate change. 

Extreme heat can put stress on the human body, exacerbating chronic conditions including respiratory disease, diabetes, cardiovascular disease, and renal disease. As days become hotter, the risk of heat illness can affect when and how people participate in outdoor recreation. For those with chronic conditions, heat can put additional stress on the heart, and some medications can interfere with the body’s ability to regulate temperature. People should talk with their health care providers about how heat exposure may interact with their medications and plan outdoor activities around high temperatures, with access to cooling spaces. 

Poor air quality can worsen chronic conditions. Cardiovascular conditions account for more than 60% of illness and deaths associated with air pollution. Wildfire smoke is also an increasingly important air-quality concern. In the Southwest, total area burned increased by an average of by 10.7% annually between 1985 – 2015. In both 2023 and 2026, smoke from Canadian wildfires traveled long distances and contributed to hazardous air quality across parts of the U.S. Midwest and East Coast. A 2024 review on the health effects of wildfires found that wildfire smoke was associated with increased respiratory illness and death, decreased lung function, and exacerbated asthma and other respiratory conditions. When wildfire smoke affects air quality, people—especially those living with respiratory or cardiovascular conditions—may need to limit or reschedule outdoor activities and monitor the Air Quality Index. 

Climate change has increased the frequency and intensity of severe weather events such as storms, floods, and droughts. These events can directly and indirectly affect health by damaging infrastructure, reducing or delaying access to care and medications, and destroying outdoor spaces. Power outages can affect medications and therapies that require refrigeration, while flooding and damaged transportation infrastructure can prevent people from reaching appointments or receiving at-home care. 

As climate change continues to impact human health, it will be vital for people to understand the connections between their health and the environment. The National Health Council strives to provide evidence-based information about how climate change can impact people living with chronic conditions and disabilities. For a visual overview, see our How Climate Change Affects People Living with Chronic Conditions and Disabilities infographic. To learn more, please visit our research briefs on climate change and extreme heat.