New study confirms value of home
CALGARY – A
just-completed study on nocturnal dialysis is the most comprehensive
ever done in the world on the night-time treatment and offers kidney
disease sufferers hope of improved cardiovascular health and greater
quality of life.
“It thins out the heart, and that’s a good thing,” says Dr. Braden Manns,
a nephrologist at the Foothills Medical Centre who oversaw the study,
along with Dr. Bruce Culleton. “People with thick hearts have a higher
chance of dying, and treatments that reduce the thickness of the heart
in the general population are associated with improved survival’.
“For these dialysis patients, we know that this treatment thins out the
heart, although in this group of patients, we don’t yet know if this
improves survival, but there is a hope. We don’t exactly know what that
means. We think it’s good. The bigger deal is people seem to feel better
on nocturnal dialysis, despite the fact they had to do dialysis every
night, they had to hook themselves up and they had to clean the machine
in the morning.”
What’s more, added Dr. Manns, “On average, patients treated with
nocturnal dialysis actually felt that kidney disease was less of a
burden on their life. There was less interruption on their lifestyle.”
Calgary, Edmonton, B.C., London, Ont. and Toronto are the only centres
in Canada currently offering nocturnal dialysis.
Calgary is the only place that has studied the treatment in a randomized
“In nephrology we have a paucity of high quality clinical studies,” says
Manns. “Perhaps that’s because historically without dialysis, patients
with kidney failure died, and now with dialysis they live. That type of
evidence was all that was required at the time, and that experience has
possibly affected the level of evidence that we are willing to accept.
For instance, if we’re offered a new dialysis filter, we often just look
at the specifications sheet and say ‘oh that’s better, we’ll just use
it, rather than studying it in a proper fashion’”
“We jump on the bandwagon based on poor quality studies,” he adds. “This
is the first study that’s actually been randomized in terms of nocturnal
dialysis. The previous studies were very small, only 20 people, this is
51. It’s still a very small study. But for a variety of reasons this may
be as big a study as we’re ever going to get.”
The two-and-a-half year study was administered at the Foothills Medical
Centre with the support of the University of Calgary, Alberta Kidney
Disease Network and Libin Cardiovascular Institute of Alberta. Half of
the patients in the study, 26, were randomly treated with nocturnal
dialysis while the other 25 were continued on conventional,
three-times-per-week hemodialysis. Each patient was studied for six
months and those on hemodialysis were given the option of switching to
nocturnal dialysis at the end of the study.
“We had a very good control group,” says Manns. “We were able to see
what happens without nocturnal dialysis and what happens with nocturnal
dialysis. That’s what we were able to do that no one else has been able
to do. What we showed is that things that had been found in previous
studies were in fact true, but others were not.
With nocturnal dialysis, patients hook themselves up to the machine that
cleans their blood in place of their failed kidneys six nights a week.
It takes about half an hour to set up the machine each night and another
half hour to an hour to clean it in the morning.
In regular hemodialysis, patients must travel to a hospital or other
care centre three times a week for four-hour dialysis sessions. Factor
in travel and waiting time, and that is a six or seven hour commitment,
three days a week.
Peritoneal dialysis is a system that allows patients to perform their
own dialysis. About 1,500 people in Southern Alberta are on dialysis and
another 1,500 have had kidney transplants.
Dr. Manns says people on dialysis, on average, have a 17 percent chance
of dying every year.
All kinds of dialysis have drawbacks. Hemodialysis is a big time
commitment and, because patients only get 12 hours of treatment a week,
it affects their energy level.
“In addition to the fact that there’s a high chance of you dying, the
quality of life isn’t very good,” says Dr. Manns of hemodialysis. “It’s
similar to what advanced cancer patients are describing. They don’t have
great energy, their diet is very restrictive, they can’t drink very much
fluid, and so for lots of reasons, the quality of life isn’t very good.”
With peritoneal dialysis, patients must live with a tube protruding from
Nocturnal dialysis is a very intensive treatment that requires four to
six weeks of full-time training for each patient. It is very expensive,
requiring patients having their own dialysis machines and a daily supply
of products for the machine.
On the plus side, the dialysis is done while the patient is sleeping,
freeing up the daytime hours for work, school or relaxation.
“For some people, nocturnal hemodialysis would not be a good choice,”
says Dr. Manns. “They would be uncomfortable doing dialysis by
themselves at home. When we were enrolling patients in our study, only
about 10 percent of our patients were interested in doing nocturnal
dialysis, though more would be capable of learning to do the treatment
themselves.” But for those 10 percent, nocturnal dialysis is another
option for their treatment.
“We want to be able to offer enough treatment options so people are able
to choose a treatment that fits into their lifestyle,” says Dr. Manns.
“Nocturnal dialysis is a great treatment for people who work during the
“Most people on dialysis aren’t working, given that dialysis is such a
big commitment, seven hours a day three times a week. By and large, the
people on nocturnal dialysis are a little bit younger. By younger I mean
less than 65 and often they have fewer other medical conditions going on
“If people are willing to trade off more extensive dialysis, six nights
a week, they will likely experience a better quality of life and they
will have lower risk of cardiovascular disease.”
While the study is the biggest ever undertaken, 51 patients, and was
randomized, Dr. Manns says a bigger study would have been better. “The
main thing we were looking at was the thickness of the patient’s heart,”
says Dr. Manns. “We saw that the thickness was reduced by about 10
percent on nighttime dialysis.
“We know that in the general population, patients who receive treatments
that reduce the thickness of the heart muscle typically live longer. But
we’ve only studied 51 patients for six months. To actually show a
difference in survival, we would have had to study about 3,000 patients
for at least a year. That study is probably never going to be done.”