Each of three prevalent therapies for end-stage renal disease (ESRD): maintenance hemodialysis (MD), continuous ambulatory peritoneal dialysis (CAPD) and kidney transplantation was devised, tested and implemented in the United States. Yet, criticism of the American system of ESRD therapy, especially MD, clouds present delivery of universal care, with accusations that physician avarice and conduct increase patient deaths.

The three principal criticisms are:

Dialysis treatments are too short. By the end of the 1980s, as the regimen for maintenance hemodialysis approached standardization, the typical prescription consisted of thrice weekly four-hour treatments, using a hollow fiber cellulose dialysis cartridge with a surface area of one square meter. The "dose" of dialysis was manipulated by using dialyzers of greater surface area, increasing blood flow rates above 300 ml/min or extending the duration of each treatment beyond four hours. Two large studies of dialysis noted that "60% of patients receive 3.5 hours or less per treatment" and asserted that "Mortality increases significantly as treatment time is reduced."

Reuse of dialyzers increases mortality. According to one researcher, "Reuse kills and everyone knows so." American gross mortality on dialysis is higher than in Europe or Japan; short treatments are much more common in the U.S.; the practice of dialyzer reuse is nonexistent in Japan, negligible in Europe and applied to the majority of patients (>70%) in the United States.

Proprietary dialysis centers do not refer for kidney transplantation. Driven by greed, it has been suggested that in the United States, for-profit ownership of dialysis facilities, as compared with not-for-profit ownership, are associated with increased mortality and decreased rates of placement on the waiting list for a renal transplant.

The debate about these three criticisms is inconclusive, primarily because the evidence developed in 1995 may no longer be applicable to therapy in progress in 2000. For example, both the measure of dialysis adequacy and the screening value indicating its attainment have been under constant change. The formula now in vogue relies on Kt/V (K relates to dialyzer surface area, t reflects time of treatment and V is the body's urea space) but has multiple confusing variations. Based on Kt/V, values for dialysis adequacy, the results in older studies would be considered unacceptably low. National Kidney Foundation developed "guidelines" (termed Dialysis Outcomes Quality Initiative [DOQI]) for prescribing adequate dialysis are gradually being adopted as a standard, with a minimal target Kt/V of 1.2 and a desired 1.3.

Present practice at large hemodialysis facilities is to prescribe three, four-hour dialyses weekly, with additional time per dialysis should target values in solute extraction not be attained. Many facilities monitor the adequacy of delivered dialysis by utilizing the simple calculation of urea reduction percentage (pre minus post urea divided by pre urea), with desired levels above 65%, which generally corresponds to a Kt/V of 1.2.

However, mathematical gauges of dialysis adequacy may be difficult to apply. For example, one of many paradoxes in Kt/V usage is that, although African-Americans systematically receive less dialysis than whites (Kt/V of 1.05 versus 1.18, respectively, both values less than the present minimal goal of 1.2), their survival is higher. Factors other than dialysis dose obviously are important determinants of longevity. As a generalization, even after adjustment for case mix, nonwhites have better survival on dialysis than whites, while receiving less dialysis. Reports from senior European nephrologists underscore, furthermore, the disconnect between mathematical modeling of dialysis and clinical outcome, either negatively or positively.

Dialyzer reuse has increased in freestanding among for-profit units to 87%, in freestanding nonprofit units to77% and in hospital units to 49%. Some critics assert that "higher rates of death and hospitalization associated with dialyzer reuse persist regardless of adjustment for demographic characteristics or baseline comorbidities."

There is, however, another side. Amazingly, credible investigators purport that there is risk to using a fresh dialyzer for each treatment in the so-called 'first dialysis syndrome.' Concurrent chest and back pain were 41 times more frequent when the dialyzer was used for the first time. The investigators who invented maintenance hemodialysis (University of Washington, Seattle) continue to believe that "dialyzer reuse is not only safe but is cost-effective and environmentally beneficial."

Criticism of American ESRD therapy has been generated by the alleged disparity between dialysis survival in Europe and Japan compared with the United States. Contrasted with the 'short' dialysis prescribed in the U.S., some centers in Europe that employ long treatment times have reported exceptionally impressive patient survival rates.

However, in-depth analysis reveals that fewer diabetics were included in the European study and the purportedly distinctly superior survival reflects misapplied statistics comparing nonequivalent cohorts. Had the cohort of diabetic patients been intermixed with the European study's selectees, the slope of survival curves would have been bent downward. In other words, when treating patients of the severity usual in U.S. dialysis units, this European facility fared no better and, in fact, even had a worse outcome. Treatment acceptance rate for diabetic renal failure patients is the product of governmental policies and economic pressures. When 'oranges are compared with oranges,' the so-called higher mortality rate of U.S. dialysis facilities fades away.

"Racial and ethnic minorities, those less well educated, and those with fewer financial resources are less likely than their counterparts to be listed for renal transplantation before dialysis." DOQI advisories do not, unfortunately, consider how a faulty patient referral process may exclude elderly, diabetic and minority group members. The exclusion of higher risk subsets ("cherry picking") selects a more favorable treatment group and leaves behind a cohort with greater risk of morbidity and death. From introspective studies in other countries, particularly the United Kingdom, it is clear that the treatment acceptance rate for diabetic renal failure patients is a correlate of governmental policies and economic pressures.

The U.S. has the highest rate of new treatment for ESRD among reporting registries worldwide. The U.S. accepts double the number (per million population) than does Europe, 40% more than Canada and 20 % more than does Japan. What is the explanation for this discrepancy?

There is no evidence in support of a higher U.S. ESRD attack rate, though U.S. minority races (African-Americans, Latinos, native Americans) have higher incidence than do whites. Excluding minorities, the U.S. white population has a higher ESRD incidence "treatment" rate (i.e., the number accepted into treatment) than do whites in either Canada or Europe. Given the scrutiny of the U.S. Health Care Finance Administration and the system of ESRD networks, it would not be possible to provide ESRD treatment for patients without documented renal insufficiency. The likely explanation for the discrepancy is that most countries do not treat a substantial portion of patients with ESRD for any of several reasons.

In Canada, the United Kingdom and Australia, subtle to overt economic and governmental pressures direct many patients to peritoneal dialysis rather than hemodialysis, while finding reasons for nontreatment of others who die untreated. A unique, though apt, example of how governmental restrictions may impact on ESRD incidence rates was revealed in the former East Germany, where treatment rates quadrupled shortly after the removal of the Berlin Wall.

Finally, the allegation that profit-directed policies trade patient lives for dollars in U.S. dialysis units doesn't make sense. The single most important variable determining the value of a dialysis unit at the time of sale is the number of patients under treatment [market price = n (number of patients) x $ (amount per patient)]. Any behavior that might kill patients (reuse, short treatments) reduces value and would be immediately discontinued. Think of the farmer selling milk (instead of the nephrologist selling dialyses). Would any threat to the milk cows be tolerated? Of course not.

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