Hotter Temperatures Linked to Health Risks Amid Climate Change

Extreme Heat from Climate Change and its Impact on Human Health

The Effect of Heat Waves on Health Care Systems

The frequency, duration, and intensity of extreme heat waves are accelerating with climate change, having devastating public health consequences. Recently, the Pacific Northwest faced a “heat dome,” where for three days, temperatures rose above 104 degrees. It sent unprecedented numbers of patients, suffering from heat stroke, to hospitals. This catastrophic event overwhelmed the hospital systems, which were already under a lot of stress and strain. Developing countries, with limited resources, are also exposed, and their citizens are more vulnerable to heat waves. As per the Centers for Disease Control and Prevention’s Heat and Health Tracker, approximately 67,500 people visit the emergency department, 9,200 people get hospitalized, and 700 people die due to heat-related issues annually in the United States. Globally, heat-related deaths increased by 68% between 2000-2004 and 2017-2021. The elderly, infants, pregnant women, people working outdoors, and those without social support systems are most vulnerable to heat waves.

The Effect of Heat on the Human Body

While humans can tolerate high levels of heat and humidity, they can do so only for short periods. When humans are exposed to heat, their core body temperature starts to rise. The body compensates through increasing blood flow to the skin and by producing eccrine sweat, which evaporates into the air, transferring heat back to the environment. Yet, the body can maintain its thermoregulatory capacity up to a certain point. Excessively humid conditions hinder sweat evaporation, which may cause the body to retain some of that excess heat, leading to heat exhaustion or heatstroke. Prolonged sweating can result in dehydration and a loss of blood volume, leading to higher core temperatures. People with pre-existing cardiovascular disease and elderly people often find themselves quickly overwhelmed, and most do not survive the heat wave.

Prompt Treatment is Critical

Cooling the body rapidly is key to saving lives and organ function. Cold-water immersion can bring down the body temperature in less than ten minutes, whereas evaporative cooling can take up to 45 minutes. As heat waves are becoming a common occurrence, prompt treatment is critical to ensuring patients’ survival. Hospitals in Seattle and the surrounding areas have implemented a disaster preparedness plan for heat events in addition to existing plans for other disasters such as earthquakes, fires, and tornadoes.

Preventing Heat Illness

The best prevention method for surviving an extreme heat event is acclimatization, which involves slowly adjusting to the heat. An average person needs exposure to heat for one to two hours over nine to fourteen days to become fully acclimatized, with most acclimatization occurring in the first four or five days. Air conditioning is useful during heat waves, ensuring that the elderly, homeless people, or individuals who do not have access to air conditioning are not affected.

Editorial and Advice

The increasing frequency, duration, and intensity of heat waves due to climate change demand that healthcare systems should enhance their disaster preparedness plans. Since vulnerable populations suffer the most, addressing socioeconomic factors, supporting social infrastructures, and improving access to air conditioning can reduce their vulnerability. Moreover, enhancing public awareness of heat-stress and promoting acclimatization can help people to prepare for and survive extreme heat events. As heat waves pose a considerable public health risk, governments and healthcare systems must understand the pathology of heatstroke, be equipped to handle a large number of patients, and save lives by cooling patients promptly. Finally, addressing climate change itself must remain a top priority to mitigate its most severe potential threats.

Reference:

Gabrielle Redford. How extreme heat from climate change affects health. AAMCNews. https://www.aamc.org/news-insights/how-extreme-heat-climate-change-affects-health