Kidney patients will be forced to skip their dialysis treatments at home because of rising energy bills, a charity has warned.
Kidney Research UK said the soaring cost of gas and electricity will mean that those on dialysis could put themselves at greater risk of dying, saying there is a 68% higher mortality rate among those who skip treatments.
There are thought to be almost 30,000 people on dialysis in the UK.
The procedure removes waste products and excess fluid from the blood when kidneys stop working properly. It can involve diverting blood to a machine to be cleaned.
Normally, the kidneys remove harmful waste products and excess fluid from the blood and turn these into urine to be passed out of the body.
Many people use dialysis machines at home to avoid three trips per week to hospital.
Kidney Research UK said it was "deeply concerned" that patients may skip sessions to save on energy bills in the middle of a cost of living crisis.
These are expected to increase by 80% in October to £3,549 a year for the average UK household, while further rises are expected next year, when the average annual bill is predicted to pass £6,000 in April.
Kidney patients on dialysis are more likely to feel the cold because blood is circulated outside of the body and then returned.
Stephen Blom, from Paisley, Renfrewshire, in Scotland, and a former champion cyclist, has been told his kidney transplant is failing after seven years and he could need to to start full-time dialysis by next month.
He said: "When you get to the dialysis stage, all your body heat goes away, you are constantly freezing.
"When I first went on to dialysis I never had the heating off. It could be a summer's day and you will have several layers of clothing on.
"If you have got the machine at home, you are having to be on it for five hours, three times a week.
"Nobody is really stepping forward and saying to us, 'Don't worry, we've got you covered.'"
Blom has IgA nephropathy, also known as Berger's disease, a kidney disease that occurs when the antibody Immunoglobulin A builds up in the kidneys, causing inflammation that damages kidney tissues.
"I was told when I got my kidney transplant that it would last 10 years, but unfortunately it's now starting to fail," he said.
"IgA rips your kidneys to pieces over time so I'm now down 10% in function. They have said I'll have to go on dialysis sooner rather than later.
"Initially, I'll be doing regular bouts in the hospital but once I see the dialysis nurse I'll request a machine at home.
"That way, I can dialyse without the pressures of having to travel to hospital from Paisley to Glasgow three times a week."
Blom, who set up a charity Return To Life to support patients, said he was fortunate that a friend has agreed to become a live donor, meaning he may not require to go on the transplant list again.
Sandra Currie, chief executive of Kidney Research UK, said: "Dialysis sessions must be kept at a regular schedule for the wellbeing of the patient and we are deeply concerned that individuals may skip at-home dialysis sessions to save on energy bills.
"Research on an international scale and in the UK has shown patients who miss dialysis sessions were not only more likely to be hospitalised but also saw a 68% higher mortality rate than those who attended every session.
"No one should have to choose between food, heat or their essential treatment and the current offering of additional financial support will only delay the impact of the crisis rather than fix a looming disaster."
Watch: Mother says it's a choice between heating and food this winter