Tag: extreme temperature

Drugs for Chronic Disease Interfere with Body’s Temperature Control Ability

Photo by cottonbro studio: https://www.pexels.com/photo/person-holding-white-round-medication-pill-4661296/

Medications to treat various chronic diseases may hinder the body’s ability to lose heat and regulate its core temperature to optimal levels. The loss of effective thermoregulation has implications for elderly people receiving treatment for illnesses like cancer, cardiovascular, Parkinson’s disease/dementia and diabetes, particularly during hot weather, according to a review by a team of scientists from various institutions in Singapore.

The group, led by Associate Professor Jason Lee from the National University of Singapore (NUS Medicine), identified and reviewed relevant research papers using keyword searches on databases such as PubMed and Google Scholar. These papers studied the associations and effects of medications on thermoregulation. The review findings were presented in a topical manner, focusing on medication classes used to treat commonly diagnosed chronic conditions (eg, diabetes, cardiovascular disease, neurodegenerative disease, and cancer). The findings were published in Pharmacological Reviews.

Health implications in clmate change

The findings show that medications used to treat common chronic conditions, like blood thinners, blood pressure drugs, Parkinson’s disease/Alzheimer’s medications, and some chemotherapy drugs, can make it harder for the human body to handle hot weather by reducing its ability to sweat or increase blood flow to the skin.

Lead author and second-year PhD candidate from the Human Potential Translational Research Programme Mr Jericho Wee said, “Rising global temperatures caused by climate change pose a significant health concern for clinical patients reliant on long-term medications and healthcare. Increasingly, we will continue to see more elderly patients, many who have multiple health conditions and are taking different types of medication concurrently to manage their chronic diseases, compounding the risk of heat-related illness and dehydration. Understanding how each medication impacts thermoregulation, in the face of warmer environments, is the crucial first step to predicting the possible health outcomes when multiple medications are taken concurrently.” While previous reviews have highlighted the impacts of medications on heat, the scope of those reviews did not present the evidence in the context of the chronic diseases and ageing. The team’s narrative review presents the evidence in the context of high ambient temperatures and their impact on chronic disease sufferers who are on long-term and life-long medication.

Senior author Assoc Prof Jason Lee said, “This review emphasises the importance of studying the mechanisms of altered thermoregulation in individuals with diabetes and other cardiometabolic conditions to prevent heat-induced conditions. This is most relevant in Singapore and many other countries, where we have rapidly ageing populations and rising ambient temperatures. Pharmacological and thermal physiologists should focus transdisciplinary efforts on this area of research to refine and enhance safe medication prescription guidelines to preserve the health of people who need these medications, even in hot weather.”

Assoc Prof Melvin Leow, the review’s co-author and Senior Consultant Endocrinologist at Tan Tock Seng Hospital said, “Physicians are often unaware of the potential harms certain drugs may cause by compromising the body’s thermoregulatory control mechanisms. This is an especially important area to delve into as those with chronic diseases and older adults are susceptible to adverse health outcomes in the heat, due to their reduced thermoregulatory capacity. It is timely and prudent that scientists and doctors collaborate even closer in this important field that cuts across a wide range of medical disciplines.”

Climate Change Will Increase Deaths Linked to Extreme Temperatures

Heat cracked earth
Photo by Joshua Woroniecki on Unsplash

The death rate linked to extreme temperatures will increase significantly under global warming of 2°C, with even steeper rises for each degree of warming, finds a report published in Environmental Research Letters.

With a warming scenario of just 2°C from pre-industrial levels, temperature-related mortality in England and Wales during the hottest days of the year will increase by 42%. This means an increase from present-day levels of around 117 deaths per day, averaged over the 10 hottest days of the year, to around 166 deaths per day. The findings underline the importance of keeping global warming levels to below 2°C.

At current global warming levels of around 1.21°C there would be a slight decrease in temperature-related mortality in winter and a minimal net effect in summer, meaning that overall, at this level of warming we see a slight decrease in temperature-related mortality rate.

The researchers assessed the impact of climate change on mortality rates England and Wales, specifically risk from heat in summer and cold in winter. They found that as the global mean temperature increases, temperature-related mortality in summer will increase at a much faster, non-linear rate.

The rate of increase particularly speeds up at 2°C of warming, with a much higher risk appearing beyond 2.5°C. The researchers say that 3°C warming could lead to a 75% increase in mortality risk during heatwaves.

The relationship between temperature and mortality on a graph is roughly U-shaped, meaning that at extremely high temperatures, mortality risk increases sharply for each degree rise of daily mean temperature.

The rate in winter will continue to decrease, although this leaves out extreme weather events such as storms.

Lead author Dr Katty Huang said: “The increase in mortality risk under current warming levels is mainly notable during heatwaves, but with further warming, we would see risk rise on average summer days in addition to escalating risks during heatwaves. What this means is that we shouldn’t expect past trends of impact per degree of warming to apply in the future. One degree of global warming beyond 2°C would have a much more severe impact on health in England and Wales than one degree warming from pre-industrial levels, with implications for how the NHS can cope.”

In England and Wales, temperature is associated with around 9% of total population mortality, meaning that 9% of all deaths during 2021 could be associated with the temperature. Most of those deaths are related to the side effects of cold weather.

The team analysed the 2018 UK Climate Projections (UKCP18) with data on present-day temperature and mortality in order to predict changes in temperature-related mortality relative to degrees of global warming.

In order to isolate the effects of global warming on mortality risk, the researchers looked at the potential impact for the current population, and not attempting to predict future age distributions and medical conditions.

Project lead Professor Andrew Charlton-Perez said: “As the Intergovernmental Panel on Climate Change impacts report recently showed, it is increasingly common to examine how different levels of mean global warming raise the risk of significant harm to people and society. Our study shows that because death rates will go up significantly if countries experience very high temperatures, limiting the average global rise in temperatures is likely to have substantial benefits for the overall health of the population.”

Source: University College London