According to forecasts, cardiovascular fatalities in the United States attributed to extreme heat are anticipated to at least double, and possibly triple, by the middle of this century if measures to reduce greenhouse gas emissions are not enacted.
A recent scholarly article in the medical journal Circulation indicates that senior citizens and African American adults are particularly vulnerable to cardiovascular mortality due to extreme heat conditions. The study predicts an increase in cardiovascular deaths by 162% by mid-century if the currently proposed U.S. policies to mitigate greenhouse gas emissions are effectively executed. An even grimmer projection anticipates a 233% increase in cardiovascular deaths from extreme heat in the next 13-47 years if only minimal efforts are taken to reduce emissions. Both scenarios reveal that the elderly and non-Hispanic black adults are disproportionately impacted.
This NIH-funded research, published on October 30 in Circulation, underscores the health inequities exacerbated by climate change, particularly its unequal impact on specific demographics, according to the study’s lead author Sameed Khatana, M.D., M.P.H., an assistant professor of medicine at the University of Pennsylvania and staff cardiologist at the Philadelphia Veterans Affairs Medical Center.
The research emphasizes the crucial role that the rate of increase in greenhouse gas emissions will play in determining the public health impact of extreme heat. Khatana suggests that robust policies to curb these emissions could potentially mitigate the adverse health outcomes associated with extreme heat.
The study leverages county-level data across the continental U.S. between 2008-2017, establishing a correlation between the number of extreme heat days and a rise in cardiovascular deaths. Utilizing models for future greenhouse gas emissions and demographic changes, the study estimates potential cardiovascular fatalities in the period 2036-2065.
Among the critical findings:
- Between 2008 and 2019, 1,651 excess cardiovascular deaths per year were associated with extreme heat.
- Even if the proposed greenhouse gas emissions reductions are fully enacted, excess cardiovascular deaths are projected to rise by 162% by mid-century when compared to the 2008-2019 baseline.
- The projections indicate that the risk among adults aged 65 and older could be 2.9 to 3.5 times greater compared to younger adults, depending on how effectively emission-reducing policies are implemented.
- Non-Hispanic black adults are projected to experience a 3.8 to 4.6 times greater risk compared to non-Hispanic white adults, depending on the implementation of greenhouse gas reduction policies.
Both medical and environmental factors contribute to the disproportionate impact on these demographic groups. Previous research has indicated that black residents may have limited access to air conditioning and may be more affected by the urban heat island effect, according to Khatana.
The results may actually be conservative estimates, as they focus only on cardiovascular deaths, not accounting for non-fatal events such as heart attacks and strokes, according to Robert Brook, M.D., FAHA, a volunteer with the American Heart Association who was not part of the study.
The research compared excess cardiovascular deaths under two Intergovernmental Panel on Climate Change scenarios: one assuming successful implementation of moderate emission reduction policies, and another with no significant emission reduction efforts. As a baseline, county-by-county records from 2008-2019 for deaths during summer months were utilized, focusing on those where the primary cause was any cardiovascular condition.
Although the data is based on continental U.S. populations, its implications may not extend to other regions. The study employs two plausible projections of extreme heat and population change, recognizing that actual changes may vary.
For further details:
Reference: “Projected Change in the Burden of Excess Cardiovascular Deaths Associated With Extreme Heat by Midcentury (2036–2065) in the Contiguous United States” by Sameed Ahmed M. Khatana, Lauren A. Eberly, Ashwin S. Nathan and Peter W. Gro, published on 30 October 2023 in Circulation.
Funding for this study was provided by the American Heart Association and the National Heart, Lung, and Blood Institute, a division of the National Institutes of Health.
Table of Contents
Frequently Asked Questions (FAQs) about Extreme Heat and Cardiovascular Deaths
What is the primary focus of the study?
The study primarily focuses on the projected increase in cardiovascular deaths in the U.S. due to extreme heat events by the middle of the 21st century. It outlines how these rates could double or triple if greenhouse gas emissions are not reduced.
Who are the most vulnerable populations according to the study?
According to the study, elderly adults and non-Hispanic black adults are the most vulnerable to cardiovascular deaths due to extreme heat.
What are the projected increases in cardiovascular deaths?
The study projects a 162% increase in cardiovascular deaths by the middle of the century if currently proposed U.S. policies to reduce greenhouse gas emissions are successfully implemented. A more dire scenario predicts a 233% increase if only minimal efforts are made to reduce emissions.
Does the study discuss any intervention methods?
Yes, the study does discuss intervention methods, such as increasing tree cover in neighborhoods, but emphasizes that more research is required to validate their effectiveness.
What are the underlying factors contributing to the impact of extreme heat on these vulnerable populations?
The study mentions both medical and environmental factors, including less access to air conditioning, less tree cover, and higher susceptibility to the ‘urban heat island effect’ for black residents. Social isolation experienced by some older adults is also identified as a contributing factor.
What does the study say about current and future greenhouse gas emission policies?
The study states that more aggressive policies to reduce greenhouse gas emissions have the potential to lessen the adverse health effects of extreme heat.
Are the projections limited to cardiovascular deaths only?
Yes, the study focuses only on cardiovascular deaths and does not account for non-fatal heart attacks, strokes, and heart failure hospitalizations, which are also likely to be impacted by extreme heat events.
Is the study applicable globally?
The study is based on data from the continental U.S. and may not necessarily apply to people living in other regions of the U.S. or the world.
Who funded the research?
The study was funded by the American Heart Association and the National Heart, Lung, and Blood Institute, a division of the National Institutes of Health.
What are the implications of this study for policy makers?
The study implies that urgent and aggressive action is needed to reduce greenhouse gas emissions. Even under moderate emission reduction scenarios, the health impacts of extreme heat are significant, underscoring the importance of immediate policy intervention.
More about Extreme Heat and Cardiovascular Deaths
- American Heart Association’s Journal Circulation
- Intergovernmental Panel on Climate Change
- National Heart, Lung, and Blood Institute
- University of Pennsylvania Medicine
- Philadelphia Veterans Affairs Medical Center
- Wayne State University School of Medicine
- Extreme Heat and Public Health
- Greenhouse Gas Emissions Data
- Climate Change and Health Equity
- Urban Heat Island Effect
5 comments
Wow, these stats are alarming. The effects of climate change are really startin to hit home, especially when it comes to public health. It’s time we all do something bout this.
Are we just gonna wait until it’s too late? with numbers like these, the risks are becoming more and more concrete. the clock is ticking, people.
The link between climate change and cardiovascular deaths is somethin I never really thought about. But now that it’s laid out, it makes complete sense. Time for some policy change.
Astonishing findings! Climate change is not just an environmental issue, it’s a serious public health crisis. Policy makers need to read this and act fast.
this is really scary stuff. the elderly and black communities are at higher risk? we’ve got to take this issue more seriously. Now.