Health Impacts of Climate Change

The body of evidence that climate change is real—whether caused by humans or by natural regulation—continues to mount, shedding little doubt that it is a phenomenon having a detrimental global impact and can no longer be ignored. As evidence, the global average temperature of the planet has increased since 1901, which may be causing the observed dangerous climate and weather shifts. Some clear examples of climate change on weather include extreme heat waves; rainfall shifts leading to increased flooding and/or intense rain in some areas and draughts in others; warming of the oceans; melting of ice caps; and rising of sea levels.

"In recent years, scientists have made significant advances in our understanding of the effects of climate change on increased risk to human health."

Many of the recent extreme weather events occurring around the planet are part of that mounting evidence of global climate change. For example:

• Many US states (eg, Arizona, Louisiana, Mississippi, New Mexico, and Texas) are setting records for extreme heat and high temperatures. Much of the eastern United States is facing daily severe thunderstorms that render hail, heavy rainfall, wind gusts, and even tornadoes which have resulted in deaths.
• In Canada, more than 900 wildfires are currently burning which has resulted in horrendous and life-threatening air quality not only in Canada, but also in some parts of the northeastern United States, including Pennsylvania, New Jersey, and New York.
• In Italy, Rome had record-high temperatures resulting in an approximately 20% increase in emergency room visits.
• In Greece, wildfires are raging in Athens and in other parts of the country.
• In France, new record-high temperatures were recorded.
• In India, water flooding from the Yamuna River overflowed into New Delhi and even reached the compound walls of the famous Taj Mahal.

The extreme heat, very poor air quality, and environmental catastrophes resulting from changes in rainfall patterns pose a dangerous threat and health risk to many individuals worldwide, especially the vulnerable.

In recent years, scientists have made significant advances in our understanding of the effects of climate change on increased risk to human health. We know that climate change affects the food supply, air quality, the availability of potable water, and adequate shelter against these ever-changing forces of nature. A population’s health and well-being can be impacted through climate change by altering the frequency and/or intensity of weather and spreading disease by the proliferation of certain pests that carry these diseases. Researchers also now better understand the long-term impact heat waves have on health. Links between sustained heat exposure and chronic health conditions such as diabetes, kidney stones, cardiovascular disease, and obesity are being established. The health effects of climate change include increased diagnoses of respiratory and heart diseases, greater prevalence of pest-related diseases like Lyme disease and West Nile Virus, elevated numbers of environmental-related illnesses, and heightened injuries and mortality. Increases in overall poor mental health have also been linked to climate change. For example, climate disasters may result in damage to homes, vehicles, and loss of loved ones which in turn increase the likelihood of mental health disorders, such as anxiety, depression, and posttraumatic stress.

All of us face some sort of health impact risk resulting from climate change. However, many face potentially higher risks depending on their exposure to these hazards, sensitivity to these exposed hazards, and ability to cope and adapt to climate-related stress. These health impact effects also do not happen in isolation, as people may face multiple threats at the same time or at different stages in their lives that accumulate over their lifetime leading to the detriment of their health. As people are exposed to multiple environmental health threats, the risk an individual has for developing a climate-related disease may increase. For example, extreme heat can not only directly result in increased heat-related illness but can facilitate poor air quality leading to other illnesses such as respiratory diseases. Additionally, changes in factors such as an individual’s personal habits, living conditions, and access to medical care can influence whether a person is exposed to health threats and whether or not they become ill. Examples of vulnerable groups that may be impacted by climate change include: low-income populations that may not have access to air conditioning in extreme heat, certain occupational groups such as construction workers who are exposed to extreme heat and disease carrying insects, pregnant women who may experience mental health issues and/or low birthweight or preterm birth, people with preexisting medical conditions such as asthma, children particularly those more sensitive to respiratory hazards, people with disabilities who have challenges in preparing and responding to extreme weather events, older adults who are at increased risk of heat-related deaths, and people living in certain locations that may be prone to flooding and hurricanes.

"As health economists and researchers, we should develop more evidence on climate change and health outcomes such as forecasting and prediction models to address the gaps and uncertainties."

 As highlighted in our feature article in this issue, climate change is expected to cause approximately 250,000 additional deaths per year from malnutrition, malaria, diarrhea, and heat stress according to the World Health Organization. The direct damage cost to health is estimated to be between $2 billion to $4 billion a year by 2030.

Looking ahead, we need to work together to address the health impacts of climate change. It starts with raising awareness of the issue, as many people are not even aware of the impact on human health due to climate change. Education will increase our collective understanding and appreciation of climate change and its impact on health and should be taught to all healthcare professionals early in and continually throughout their careers. These professionals should also be provided with the tools and skills to effectively communicate the health impacts of climate change to patients. Partnering with community organizations, including profit and nonprofit organizations, churches, governments, etc to communicate to the broader community key messages about health risks associated with climate change and other environmental factors is also important. As health economists and researchers, we should develop more evidence on climate change and health outcomes such as forecasting and prediction models to address the gaps and uncertainties. By having more data and evidence, we can make an impact on policy changes for the betterment of society. As individuals, we can all do our part to reduce the effects of climate change by making minor changes to our everyday life, such as saving energy, using cleaner energy, reducing waste, reducing the environmental impact of fuel emissions, conserving water, and addressing disparities in healthcare as part of environmental justice initiatives. By working together, we can improve health outcomes related to climate change and the environment and make a change for a better tomorrow.

As always, I welcome input from our readers. Please feel free to email me at zeba.m.khan@hotmail.com.