The Case for Every-Other-Day Dialysis

A need for a paradigm shift in focus: From Kt/Vurea to appropriate removal of sodium (the ignored uremic toxin)

Hemodialysis for chronic renal failure was introduced and developed in Seattle, WA, in the 1960s. Using Kiil dialyzers, weekly dialysis time and frequency were established to be about 30 hours on 3 time weekly dialysis. This dialysis time and frequency was associated with 10% yearly mortality in the United States in 1970s. Later in 1970s, newer and more efficient dialyzers were developed and it was felt that dialysis time could be shortened. An additional incentive to shorten dialysis was felt to be lower cost and higher convenience. Additional support for shortening dialysis time was provided by a randomized prospective trial performed by National Cooperative Dialysis Study (NCDS). This study committed a Type II statistical error rejecting the time of dialysis as an important factor in determining the quality of dialysis. This study also provided the basis for the establishment of the Kt/V_urea index as a measure of dialysis adequacy. This index having been established in a sacrosanct randomized controlled trial (RCT), was readily accepted by the HD community, and led to shorter dialysis, and higher mortality in the United States. Kt/V_urea is a poor measure of dialysis quality because it combines three unrelated variables into a single formula. These variables influence the clinical status of the patient independent of each other. It is impossible to compensate short dialysis duration (t) with the increased clearance of urea (K), because the tolerance of ultrafiltration depends on the plasma-refilling rate, which has nothing in common with urea clearance. Later, another RCT (the HEMO study) committed a Type III statistical error by asking the wrong research question, thus not yielding any valuable results. Fortunately, it did not lead to deterioration of dialysis outcomes in the United States. The third RCT in this field ("in-center hemodialysis 6 times per week versus 3 times per week") did not bring forth any valuable results, but at least confirmed what was already known. The fourth such trial ("The effects of frequent nocturnal home hemodialysis") too did not show any positive results primarily due to significant subject recruitment issues leading to inappropriate selection of patients. Comparison of the value of peritoneal dialysis and HD in RCTs could not be completed because of recruitment problems. Randomized controlled trials have therefore failed to yield any meaningful information in the area of dose and or frequency of hemodialysis.

New Approaches to Hemodialysis

Treatment of end-stage renal disease with dialysis is characterized by high mortality rate, low quality of life, and high cost. Recent randomized controlled studies showed that increasing the dialysis dose above the currently recommended levels in thrice-weekly hemodialysis does not decrease the patient mortality rate. Short daily hemodialysis or daily home nocturnal hemodialysis are promising alternatives. Both improve quality of life and control blood pressure and anemia; nocturnal hemodialysis additionally controls serum phosphates without phosphate binders, allows a free diet, and corrects sleep apnea. Although the direct cost of daily hemodialysis is higher than that of conventional hemodialysis, the cost of total care, especially when delivered at home, seems to be lower. Further confirmation of these results is important. Restructuring of the dialysis reimbursement system is necessary to make the use of daily hemodialysis possible. Hemofiltration techniques, sorbents, and the renal tubular assist device may also help change the current grim statistics.

Starting a home hemodialysis program: single center experiences

OBJECTIVES

Home hemodialysis (HHD) has been used only in a minority of patients over past years although it may offer significant advantages over the other renal replacement therapies. This study describes the systems for and the initial results of starting a HHD program.

MATERIAL AND METHODS

A program for HHD was instituted at a university hospital having more than 20 years of experience in training patients for self-care hemodialysis. A working group designed the patient and partner education program, installations, water quality assurance, logistics, and control systems.

RESULTS

Between May 1998 and May 2001, 37 patients with a mean age of 48.3 +/- 12.5 (24-71) years were trained for HHD (1.0 patient/month) the mean training time being 2.0 +/- 0.6 (1-3) months. Four patients had no helper at home. The dialysis schedules (timing, frequency, duration) were individualized at home 41% of the patients having more frequent and/or longer treatments (including long-slow night and daily short HHD). The weekly dialysis time increased from 13.9 +/- 1.5 (CI 13.4-14.4) initially to 15.5 +/- 3.7 (CI 14.2-16.7) h (p = 0.008) at the end of follow-up. Significantly (p < 0.05) increased serum creatinine concentration was observed during the follow-up suggesting for an increased muscle mass. Initially 32% and at the end of follow-up 60% of the patients required no antihypertensive drugs (p < 0.05). Seventeen of the 21 drop-outs were caused by renal transplantation and the most common causes necessitating hospital back-up were related to vascular access.

CONCLUSIONS

In conclusion the HHD program started in a unit having experience on and commitment for training self-care hemodialysis enabled individualization of the dialysis schedules resulting in the institution of long-slow (night) and alternate day as well as daily HHD therapies. It improved the control of hypertension renal transplantation being the single most common cause of drop-out.