London-based study examines optimal dialysis temperature in largest trial to date

Dr. Amit Garg. Photo via

Findings from the largest hemodialysis clinical trial conducted by scientists in London shows using cooler temperatures has no increased benefits, despite older studies suggesting otherwise.

The MyTemp Study, published in the weekly medical journal Lancet, included findings from the trial through Lawson Health Research Institute, ICES Western and Western University and found lowering the dialysis temperatures does not improve patient outcomes when it comes to cardiovascular-related deaths and hospitalizations, nor does it maintain better blood pressures during treatment.

“The studies have been limited, especially in numbers, yet the practice of lowering the dialysis temperature has become a practice growing in popularity. Some institutions have even made this a centre-wide policy for all hemodialysis patients,” said Dr. Amit Garg, a Lawson scientist, site director for ICES Western, and associate dean of clinical research at the Schulich School of Medicine and Dentistry. He also works as a nephrologist, which is someone who specializes in treating and diagnosing kidney disorders, at the London Health Sciences Centre (LHSC).

Over the past four years, researchers studied the outcomes of both standard and cooler dialysis treatments in over 15,000 patients at 84 of 97 hemodialysis centres in Ontario. Ten of the centres operated through the LHSC. In terms of the number of patients, the study is the largest of its kind ever published.

The trial included a total of 4.3 million dialysis treatments. Patients were randomized to receive treatment with either the standard temperature or a lowered temperature of 0.5 C to 0.9 C below each patient’s measured pre-dialysis body temperature, with a lowest recommended temperature of 35.5 C.

“We wanted to determine if lowering the dialysis temperature would help people live longer and healthier,” said Garg. “We also measured symptoms and how people felt on the dialysis. We set out to collect high-quality evidence to make sure we are doing the right thing for patients.”

Garg said researchers did not find any benefits to patients who were given cooler treatments. There were no improvements to cardiovascular health and some actually said they experienced discomfort from the lowered dialysis temperature.

“The results suggest we should not be adopting lower dialysis temperatures, as a centre-wide policy, and its utility in select patient care warrants scrutiny,” Garg added.

According to the Kidney Foundation of Canada, 1 in 10 Canadians are living with kidney disease. Most kidney diseases attack the filtering units of the kidneys, known as the nephron which can damage their ability to eliminate wastes and excess fluids. Kidney disease can range from mild to severe, and can sometimes lead to kidney failure.