Extreme temperatures increase risk of death from heart failure

A new study conducted shows that exposure to extreme heat or cold increases the risk of death in heart patients.

This graph shows temperature percentiles and relative risk (RR) of death from heart disease for 567 cities worldwide. The dashed line represents the temperature with the lowest mortality risk. Dotted lines represent the 1st percentile (extremely cold) and 99th percentile (extremely hot).Image Credit: Circulation

The study was recently reported in the Journal of the American Heart Association. circulation.

A global analysis of more than 32 million cardiovascular deaths over 40 years reported more deaths on days with the hottest or coldest temperatures compared to days with mild weather.

Highlights the urgent need to develop measures to help society mitigate the effects of climate change on cardiovascular disease.”

Haitham Khraishah, MD, University of Maryland School of Medicine, Study Co-Author and Cardiovascular Fellow

Among the types of cardiovascular disease, people with heart failure are most likely to be adversely affected by very cold and very hot days, and in certain cities die on days of extreme heat rather than optimal temperatures. 12% higher risk. Extreme cold increased the threat of death from heart failure by 37%.

Results relied on analysis of health data from over 32 million cardiovascular deaths that occurred in 567 cities in 27 countries on five continents between 1979 and 2019. Descriptions of extreme weather varied from city to city.

This was identified as the temperature with the lowest mortality rate, the top 1% or bottom 1% of the so-called ‘minimum mortality temperature’.

For every 1,000 cardiovascular deaths, researchers found:

• An extremely hot day (above 86°F in Baltimore) could kill 2.2 people.
• 9.1 additional deaths were reported on extremely cold days (below 20°F in Baltimore).
• Among the types of heart disease, the highest number of extra deaths was found in people with heart failure (2.6 extra deaths on extremely hot days and 12.8 extra deaths on extremely cold days).

We do not know why the effect of temperature was more pronounced in patients with heart failure, but it may be due to the progressive nature of heart failure as a disease.. One in four heart failure patients is readmitted within 30 days of hospital discharge, and only 20% of heart failure patients survive 10 years after diagnosis..”

Haitham Khraishah, MD, University of Maryland School of Medicine, Study Co-Author and Cardiovascular Fellow

Climate change is known to bring extreme weather on both ends of the spectrum.His 2021 study published in the journal chemistry found that Arctic warming altered the event, interrupting the polar vortex and causing periods of extreme cold in the northern hemisphere.

Barrak Alahmad, MD, Ph.D., a research fellow at the Harvard TH Chan School of Public Health at Harvard University in Boston and a faculty member at the School of Public Health at Kuwait University in Kuwait City, is the corresponding author of the study. did.

Over the past four years, Dr. Khraishah and Dr. Alahmad, with collaborators at more than 35 institutions around the world, have taken steps to build a heart disease mortality database for this study.

The team created and extended the Cardiac Mortality Database as part of the Multi-Country, Multi-City (MCC) Collaborative Research Network. Known as a consortium of biostatisticians, epidemiologists and climate scientists, it is learning about the health impacts of climate and the effects of associated environmental stressors on mortality.

This study provides a clear link between temperature extremes and mortality from heart disease from one of the largest multinational datasets ever collected.. You can dig deeper into the data to learn more about the role of health disparities and genetic predispositions in making some populations more vulnerable to climate change. “

Mark T. Gladwin, M.D., Dean, University of Maryland School of Medicine

Gladwin is also Vice President of Medical Affairs. University of MarylandBaltimore, and Distinguished Professors John Z. and Akiko K. Bowers.

Such questions will be answered in future research, according to Dr. Kleischer.

Some limitations of this study are the underestimation of data from South Asia, the Middle East, and Africa.

Scientists also considered humidity and air pollutants. This may have contributed to excess mortality at extreme temperatures. We also adjusted the lagging effect of temperature on climate zones and human health (lag effect).

“This groundbreaking paper calls for viewing climate change as a growing public health concern and emphasizes the need to investigate climate change as a potential cause of health inequalities.said Steven N. Davis, MBBS, medical director of UMSOM and chief physician of UMMC.

This research was financially supported by the Kuwait Foundation for Scientific Advancement.