By Milliam Murigi
Over the last decade, kidney diseases have increased significantly across the world, emerging as one of the fastest-growing non-communicable diseases (NCDs) globally.
According to World Health Organisation (WHO), globally, Chronic Kidney Disease (CKD) cases rose from about 276 million in 2016 to about 674 million in 2026.
Nearly 174 million people affected by the disease reside in sub-Saharan according to a recent report.
Though the burden of kidney disease is rising in parallel with diabetes, hypertension and population ageing, doctors have started to document a disturbing trend.
An increasing number of young people with no traditional risk factors for chronic kidney disease are now being diagnosed with the condition.
Ahmed Hassan, a 32-year-old Sudanese farmer, is one of the young people suffering from this disease since last year. For him, the danger began as exhaustion.
Like many farmers in the country which experiences temperature of up to 40 degrees Celsius, he ignored the dizziness, muscle cramps and persistent fatigue that came after long hours under the scorching sun.
“I thought it was normal tiredness from farm work,” he reportedly told local health workers during one of the hospital visits.
Months later, his condition worsened. His legs began to swell, he struggled to urinate and developed constant nausea. At a local hospital, doctors delivered devastating news: his kidneys were failing.
What shocked doctors most was that Hassan had none of the traditional risk factors associated with chronic kidney disease (CKD). He did not have diabetes or hypertension and was otherwise young and physically active.
Instead, physicians linked his illness to repeated dehydration and prolonged exposure to extreme heat a condition now increasingly recognized globally as chronic kidney disease of non-traditional causes (CKDnt).
“Traditionally, chronic kidney disease has largely been linked to established medical conditions such as diabetes, hypertension and other cardiovascular disorders, with most cases occurring in older populations where long-term illness gradually impairs kidney function,” says Dr. Jack Kileba, a medical doctor working with Bayer healthcare.
The disease is becoming one of the clearest examples of how climate change is quietly reshaping human health. According to Dr. Kileba, kidney complications are becoming more common as heatwaves grow longer and more intense.
“When there is increasing heat, people perspire and lose a lot of water from the body. This causes hypovolemia, or low blood volume. Reduced blood supply to the kidneys can trigger acute kidney injury and repeated injury eventually leads to chronic kidney disease,” he said.
The kidneys depend on a stable flow of blood and fluids to filter toxins from the body. But when extreme heat causes repeated dehydration, the organs become stressed and damaged over time.
Researchers say the problem is particularly severe among people whose livelihoods depend on working outdoors such as farmers, construction workers, boda boda riders, miners and casual labourers. The reason is, for many low-income workers across Africa, taking breaks from the heat is often a luxury they cannot afford.
“We are realizing this is occupational. Most of the affected are outdoor workers, although research is still in its early stages and evidence is still emerging,” added Dr.Kileba.
In Sudan, the crisis has intensified under the combined weight of conflict, displacement and climate shocks. Humanitarian organizations operating in Darfur and Khartoum have reported increasing cases of dehydration-related illnesses among displaced populations living in overcrowded camps with limited access to safe drinking water.
But Sudan is not alone. Across the world, researchers are documenting similar patterns in countries experiencing rising temperatures. In Central America, the condition has devastated agricultural communities, earning the nickname “the epidemic of the sugarcane workers.” In India and parts of Sri Lanka, doctors have also reported increasing cases among farmers exposed to prolonged heat stress.
Now, health experts fear the rest of Africa could be next. Kenya’s climate projections paint a troubling picture. According to government climate adaptation plans, average temperatures are expected to continue rising over the coming decades, increasing the frequency and severity of heatwaves. That could expose millions of outdoor workers to dangerous levels of heat stress.
“If we do not succeed in mitigating climate change and introducing preventive measures, then unfortunately the number of kidney disease cases will increase,” warned Dr. Kileba.
According to him, the threat goes beyond kidney disease alone. Extreme heat also strains the cardiovascular system, increasing the risk of hypertension and heart disease. Air pollution linked to climate change worsens respiratory illnesses, while changing environmental conditions are also associated with some cancers and infectious diseases.
Yet kidney disease remains among the least discussed climate-related health emergencies. Unlike floods or droughts that produce visible destruction, kidney damage often develops slowly and silently. Many patients only discover the illness after irreversible damage has already occurred.
For families, the consequences can be devastating. Treatment for advanced kidney disease is expensive and often inaccessible. Dialysis requires specialized machines, regular hospital visits and reliable electricity resources that remain scarce in many African countries. For poorer households, a diagnosis can quickly become a financial catastrophe. Communities also need greater awareness about the early warning signs of heat-related illness.
“Prevention remains the most effective solution. Governments need to establish heat warning systems, increase access to clean drinking water and enforce safer working conditions for outdoor labourers. Simple interventions such as shaded rest areas, scheduled cooling breaks and hydration education could save lives,” adds Dr. Kileba.
“We must build systems that help communities’ adapt. People need to know when temperatures are dangerously high and what precautions to take.”
But adaptation alone will not be enough. Dr. Kileba says that since climate change is a global crisis, it requires coordinated international action to reduce greenhouse gas emissions and slow global warming. Without urgent intervention, rising temperatures could trigger a new generation of climate-linked diseases across vulnerable populations.
