Frequent and longer dialysis treatments may provide more benefits for patients than conventional dialysis treatments, according to several studies appearing in upcoming issues of the Journal of the American Society Nephrology (JASN). The findings suggest that daily or nightly dialysis sessions at home or in the clinic are viable - and perhaps superior - alternatives for some patients with kidney failure.

Most kidney failure patients who undergo dialysis receive treatments at outpatient facilities three times per week, for three to four hours per visit. Researchers suspect that more frequent and longer treatments might be more effective, but these would be inconvenient for most patients and would take up too much of their time. Therefore, nighttime dialysis while patients sleep (at home or in a clinic) or daily treatments at home might be good options.

Several groups of researchers set out to test these alternatives. Their findings are summarized below.
  • Eric Weinhandl (Minneapolis Medical Research Foundation) and his co-investigators compared survival of 1,873 daily home dialysis patients using the NxStage System One - a portable hemodialysis machine for use in the home - between 2005 and 2008 with 9,365 thrice-weekly in-center hemodialysis patients. Over an average period of 1.7 to 1.8 years, daily home dialysis patients were 13% less likely to die than thrice-weekly clinic patients, and the survival benefit of daily home dialysis appeared to apply to all types of patients (different sexes, races, weights, etc.). "Whether these results apply to all hemodialysis patients needs further study because patients in our analysis were generally younger and less sick," said Weinhandl.
  • Gihad Nesrallah, MD, Rita Suri, MD (University of Western Ontario, in London, Canada), and their team compared 338 patients who received intensive home hemodialysis (during the day or night) for an average of 4.8 sessions per week and an average treatment time of 7.4 hours per session with 1,388 patients who received conventional hemodialysis. After following patients for an average of 1.8 years, the researchers found that patients receiving intensive dialysis were 45% less likely to die than patients receiving conventional dialysis. "Whether this improvement in survival is due to increased intensity of dialysis itself or due to the fact that the intensive dialysis patients performed their own dialysis treatments at home is not yet clear," said Dr. Suri.
  • Eduardo Lacson, Jr., MD (Fresenius Medical Care North America) and his colleagues studied the health of 746 patients who received hemodialysis treatments at a clinic for three nights per week and for an average of eight hours per night, compared with 2,062 similar patients who received conventional hemodialysis treatments. During a two-year follow-up period, patients who received nighttime dialysis had a 25% reduced risk of dying compared with conventional dialysis. Nighttime dialysis patients also experienced improvements in certain measures such as lower weight, blood pressure, and blood phosphorous levels. "This comparison primarily evaluated the impact of the length of treatment time on hemodialysis because patients were all dialyzed in the center and at the same frequency of three times per week," said Dr. Lacson. "Longer treatment time allows for removal of fluid and waste products at a slower pace, but with the added benefit of potentially removing larger quantities from the body."
  • Finally, John Daugirdas, MD (University of Illinois at Chicago) and his team analyzed data from two studies, the Frequent Hemodialysis Network Daily and Nocturnal Trials, which compared frequent (six times per week) treatments received during the day or at night, with conventional dialysis. Daugirdas and his colleagues looked to see if more frequent dialysis treatments could help lower patients' blood phosphorus levels. (Traditionally, dialysis patients often have high levels, which puts them at risk of developing various complications such as heart disease.) Compared with conventional dialysis treatments, daily or nightly dialysis treatments for 12 months lowered patients' phosphorus levels and reduced their need for phosphorus-lowering medications.
The studies' findings indicate that additional research is warranted to determine if extended or more frequent dialysis treatments provide benefits for all dialysis patients and to determine the optimal treatment frequency and session length.