Short Daily Dialysis Can be Too Short
By Peter Laird, MD
The Frequent Hemodialysis Network Trial Group results published in November 2010 has focused many providers interest in short daily dialysis since the results of this randomized and controlled trial dramatically showed the benefits of short daily dialysis. The study endpoints of reduced LVH and improved physical-health composite score is a long awaited result from a randomized and controlled trial. In addition, the long standing argument of how much dialysis and at what dose is best for patients stands on the side of the dozens of observational studies showing a benefit to more frequent and longer duration dialysis. The gold standard of dialysis care is daily, nocturnal dialysis of 6-8 hours duration done at low blood flow and low ultrafiltration rates.
The NxStage System One portable home dialysis machine introduced a new wave of interest in home based therapies especially in the last five years. Many now use the NxStage machine as short daily hemodialysis. Combined with the ease of learning and using this system, patients are now free to dialyze in the comfort of their own home. However, many patients will be tempted to shorten their daily treatments to augment lifestyle changes and freedom. Dr. Kjellstrand, et al published an important paper in September 2010 looking at the total weekly duration of dialysis and mortality. They found that sometimes, short daily dialysis can be too short:
Survival with short-daily hemodialysis: Association of time, site, and dose of dialysis
Short-daily hemodialysis can be too short. In this series of patients, every extra hour spent on dialysis was associated with better survival. This finding is in agreement with those of others analyzing thrice-weekly dialysis5–8 and interestingly is seen even in patients treated by long night hemodialysis, where the weekly dialysis hours are 2 to 4 times longer than in our patients on SDHD.12
Patients considering home hemodialysis should bear in mind that time on dialysis correlates directly to survival. For those considering short daily dialysis, avoiding total dialysis times less than 15 hours each week should be in the forefront of discussions with your medical team. When coupled with the information of the FHN showing more frequent dialysis benefits, the optimal approach is to maximize time and frequency of sessions individualized to patients schedules and lifestyles. We are once again coming full circle back to Dr. Scribner’s wisdom of the Hemodialysis Product where he correlated survival based on a simple calculation of frequency and time on dialysis back in 2002.
http://www.hemodoc.com/2011/01/short-daily-dialysis-can-be-too-short.html
You are absolutely right, Peter. One of my favorite dialysis papers ever is Rajiv Saran et al’s DOPPS paper on treatment time. Here’s the abstract for those of you who haven’t seen it:
Kidney Int. 2006 Apr;69(7):1222-8.
Longer treatment time and slower ultrafiltration in hemodialysis: associations with reduced mortality in the DOPPS.
Saran R, Bragg-Gresham JL, Levin NW, Twardowski ZJ, Wizemann V, Saito A, Kimata N, Gillespie BW, Combe C, Bommer J, Akiba T, Mapes DL, Young EW, Port FK.
Division of Nephrology and Kidney Epidemiology and Cost Center, University of Michigan, Ann Arbor, Michigan 48103-4262, USA. rsaran@umich.edu
Comment in:
Kidney Int. 2006 Nov;70(10):1877; author reply 1877-8.
Abstract
Longer treatment time (TT) and slower ultrafiltration rate (UFR) are considered advantageous for hemodialysis (HD) patients. The study included 22,000 HD patients from seven countries in the Dialysis Outcomes and Practice Patterns Study (DOPPS). Logistic regression was used to study predictors of TT > 240 min and UFR > 10 ml/h/kg bodyweight. Cox regression was used for survival analyses. Statistical adjustments were made for patient demographics, comorbidities, dose of dialysis (Kt/V), and body size. Europe and Japan had significantly longer (P < 0.0001) average TT than the US (232 and 244 min vs 211 in DOPPS I; 235 and 240 min vs 221 in DOPPS II). Kt/V increased concomitantly with TT in all three regions with the largest absolute difference observed in Japan. TT > 240 min was independently associated with significantly lower relative risk (RR) of mortality (RR = 0.81; P = 0.0005). Every 30 min longer on HD was associated with a 7% lower RR of mortality (RR = 0.93; P < 0.0001). The RR reduction with longer TT was greatest in Japan. A synergistic interaction occurred between Kt/V and TT (P = 0.007) toward mortality reduction. UFR > 10 ml/h/kg was associated with higher odds of intradialytic hypotension (odds ratio = 1.30; P = 0.045) and a higher risk of mortality (RR = 1.09; P = 0.02). Longer TT and higher Kt/V were independently as well as synergistically associated with lower mortality. Rapid UFR during HD was also associated with higher mortality risk. These results warrant a randomized clinical trial of longer dialysis sessions in thrice-weekly HD.
Thanks Dori, that is one of the first articles you taught me when I first began to learn about optimal dialysis from you and Bill back in 2008. It simply boggles my mind why such important clinical information is not utilized more frequently.
Too much information! Each month, probably 100,000 new articles come out in the medical journals. Maybe more. I’ve found that even well-informed, prominent nephrologists can have huge gaps in their knowledge base. People learn about what they’re interested in. And since dialysis is the Rodney Dangerfield, if you will, of nephrology, there’s little incentive for it to be the focus of journal reading, when there is so little time…
Plus, I think that those of us who read the literature form a narrative out of what we pull together. There’s certainly a bias toward seeking information that confirms our world views. My world view includes a belief that dialysis that is more physiologic has better outcomes. Seems like common sense to me–a no brainer. But, as you know, not everyone agrees. Either they don’t know the literature or it’s not randomized enough for them.