Kidney Dialysis Best After Dark?
Frequent Nighttime Dialysis May Trump Fewer Daytime Dialysis Sessions
Sept. 19, 2007 -- Getting kidney dialysis frequently at night may be better
than getting daytime dialysis less often, a new study shows.
If confirmed, the findings may help dialysis patients live longer and
healthier lives, according to an editorial published with the study in today's
edition of The Journal of the American Medical Association.
Dialysis treatment, which uses artificial devices to perform the kidneys'
functions, is necessary for cases of advanced
The new kidney dialysis study included 52 Canadians with end-stage renal
(kidney) disease. The patients -- who were in their early to mid-50s, on
average -- were getting kidney dialysis three times per week at dialysis
Half of the patients stuck with that dialysis schedule. The rest were
trained to give themselves kidney dialysis at home, six nights per week.
Heart scans taken at the beginning and end of the six-month study show a
difference between the two groups.
Dialysis Study's Findings
Kidney disease puts people at risk for heart disease. One sign of heart risk
is an enlarged left ventricle, the heart's powerful pumping chamber.
The left ventricle shrank in the patients who got nighttime dialysis but
grew slightly in those who got daytime dialysis. That suggests a possible heart
benefit from nighttime dialysis.
Patients who got nighttime dialysis also improved their blood pressure and
mineral levels, and they were able to cut back on their use of blood pressure
drugs and other medications,
The patients also completed surveys about their quality of life.
Overall quality-of-life ratings weren't very high for any of the patients.
But patients reported feeling less burdened by their kidney disease after
starting nighttime dialysis.
The study has some limits. The patients were all accustomed to dialysis, so
it's not clear if newcomers to dialysis would master the technique as well.
Also, the study was relatively small and short, so the findings need to be
confirmed in future studies.
The researchers -- who included the University of Calgary's Bruce Culleton,
MD -- aren't sure exactly why nighttime dialysis trumped daytime dialysis.
The patients who got nighttime dialysis spent more time getting dialysis,
and that "likely was the critical element," write Culleton and
The study's results are "impressive," but it would be interesting to
see if the effects last beyond six months, writes editorialist Alan Kliger, MD,
of Yale University and the Hospital of St. Raphael in New Haven, Conn.