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 kidney disease.
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 centers.
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.
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 colleagues.
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.