Experts heard by The Guardian call for more urgent studies between heat and CHDu – chronic kidney disease of uncertain cause – to assess the potential scale of the situation.
Unlike chronic kidney disease (CKD), which is a progressive loss of kidney function widely seen among the elderly and people with other diseases such as diabetes and hypertension, CKD epidemics are emerging in rural regions with high temperatures. in countries such as El Salvador and Nicaragua, where a large number of rural workers began to die from irreversible renal failure.
There have also been cases of CKDu in people who carry out heavy manual work in hot zones in other parts of the American continent, the Middle East, Africa and India. The kidneys are responsible for the fluid balance in the body, which makes them particularly sensitive to extreme temperatures. There is an emerging consensus that CKDu should be recognized as a heat-related injury, in which workers develop subtle kidney damage every day while in agricultural fields. This in turn can progress to severe kidney disease or chronic kidney failure over time.
This attack on the kidneys is not always accompanied by symptoms, which can cause workers to end up with end-stage chronic kidney disease.
For Tord Kjellstrom of the National Center for Epidemiology and Population Health at the University of Australia, heat stress is not receiving the necessary attention in debates on how to mitigate the first effects of the climate emergency.
“As the number and intensity of hot days increases, more and more people who work will face even greater challenges in avoiding heat stress, particularly two-thirds of the global population living in tropical and subtropical areas. Heat exhaustion threatens the livelihoods of millions of people and undermines efforts to reduce poverty,” he stresses.
“Global warming is a serious threat to the lives of workers and the livelihoods of millions of people. Emerging climate policies must take this into account if we are to have any chance of facing what is to come”, Alerted Tord Kjellstrom.
According to physician Cecilia Sorensen, director of the global consortium on climate and health education at Columbia University, “we have no idea what the extent of the problem is because we are not monitoring it.”
“There are some regions that are clearly hot spots., but in terms of its prevalence and how serious the problem is, I don’t think we’ve started to get involved in it yet,” he added. However, documented epidemics have similar characteristics. Those affected tend to be people who work in hot conditions outdoors and come from disproportionately vulnerable environments – socially and economically – with limited access to medical care or insurance, or live in areas with poor health infrastructure.
According to Cecilia Sorensen, “according to current data, it seems that renal severity worsens the more vulnerable and desperate the worker becomes. Those who do not have control over their working conditions or are encouraged to work longer hours without breaks, such as those who are paid for the number of fruit they harvest or the amount of cane they cut, are the most affected”.
“They are getting sick from the work they do and have no other options. There is little supervision in the work environment to prevent this from happening. It’s a human rights issue”, Frieze.
Ramón García Trabanino, a nephrologist and medical director of the El Salvador Hemodialysis Center, told reporters The Guardian who first noticed an unusual number of patients with CKD at the hospital where he has worked for more than two decades.
“They were young and they were dying because we didn’t have the money or the ability to do dialysis treatments. We did the best we could, but they continued to die. And more and more they arrived with the same symptoms”, he stated.
Ramón García Trabanino is analyzing similar epidemics in Mexico, Nicaragua, Costa Rica and Panama.
“If we look at the maximum temperatures in the Central American region, we see that they correspond to the regions where we are describing the disease. In El Salvador and Nicaragua, mortality rates are about 10 times higher than expected. The number of new patients is impressive”.
Despite the consensus view that CKDu is related to heat and dehydration, some scientists believe that exposure to agrochemicals and infectious agents, as well as genetic makeup and risk factors related to poverty, malnutrition and other social determinants of health, they can also play a role.
Richard Johnson, Professor of Medicine at the University of Colorado says: “What is less clear is the fact that recurrent heat stress is not just a problem in sugarcane fields in Nicaragua. Even in our societies, the possibility of heat stress and dehydration can play a role in kidney disease.”