By Kurt Ullman, Contributing Writer, MedPage Today
Published: December 02, 2011
Reviewed by Robert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco and
Dorothy Caputo, MA, RN, BC-ADM, CDE, Nurse Planner
Organ quality is important to patients, but not well understood, when "shopping" for a liver to transplant, according to a recent survey.
An initial survey of 10 people on the waiting list at a major transplant center found a very poor understanding of the spectrum of organ quality. Most tended to say that livers were either good or bad and that the facility would only offer them the very best available, reported Michael L. Volk, MD, and colleagues from the University of Michigan in Ann Arbor.
Using these findings as a base, a larger group of 95 people was surveyed. The mean risk of acceptable graft failure was 32% at three years after transplantation, the researchers wrote in the December issue of Liver Transplantation.
Despite being told that stringent standards would lower the number of livers available, 58% would accept only livers with graft failure estimates of 25% or less at three years and 18% would only accept those with the lowest possible risk (19% at three years).
The quality of donor livers can vary greatly depending on age, cause of death, steatosis, and ischemia time; those factors can make the difference between 20% and 40% rates of graft failure three years after transplantation, the authors noted in their introduction.
In addition, the quality of donor livers is expected to decrease over time, both because the population is aging and because more people have experienced a stroke as a cause of brain death, the authors noted. As well, a federally funded group is promoting the use of extended criteria donor organs, which will expand the donor pool but also will increase the chance of graft failure.
As a result, discussions of organ quality with patients are more essential than ever, but hard to make time for in a busy clinic. "It is challenging to discuss the use of high-risk organs with patients, in part because of the lack of information on how patients view the topic," wrote the authors.
To find out more about how patients were thinking about these issues, the investigators conducted a two-part study. The first part consisted of a semi-structured interview of 10 patients on the waiting list. The questions at the start were open-ended, but as they continued, they became more focused on finding participants' preferences based on their understanding of organ quality.
The second part consisted of three sections on a computerized survey. They looked at education about the differences in liver quality and what that meant when considering graft failure, patient preferences about the level of risk they would accept, and 10 covariates the researchers thought might influence patients' decision-making.
A bias against lower-quality organs occurred when participants were asked to decide between staying on the list with a 20% chance of dying in three years or accepting a lower-quality organ with a 20% chance of dying but an improved quality of life. Despite having the logically correct answer to accept the liver, 42% still opted to stay on the list.
When the researchers changed the format in which they presented the information, they found a significant impact on patient preferences.
Those who were first presented a graph showing the best possible outcome would accept risk of failure up to 25% on average. Those who saw a graph with the 25% risk of failure (the average for the center) would accept up to a 29% risk on average (P=0.001).
Some participants were presented with a pie-chart pictograph showing graphically what percentage of organs would fail at a given risk level. The initial average failure risk they would accept at three years (28%) increased to 32% once they had seen the pictograph (P=0.003).
Among the 67 who wanted only organs with a 25% or less chance of graft failure, 19% would accept higher risk after the feedback was given. Conversely, only 7% of those who would accept organs with more than 25% failure risk reduced their risk tolerance.
Among the demographic and clinical covariates examined, only sex was associated with risk preference.
After feedback was given, men preferred organs with a lower failure risk than women (29% versus 35%, P=0.04). Only belief in control was significant among the psychological measures, with patients having a more external locus of control more likely to accept higher-risk organs (P=0.04).
Twenty patients were surveyed again after a mean time of 16 months (range 6 to 30 months). As a group, their risk preferences had not changed significantly, with mean acceptable graft failure risk being 34% initially and 33% at the second instance (P=0.3).
But as individuals, the preferences were not stable, with only a modest correlation between initial and re-approached values (Spearman's P=0.24).
"This study of patient decision-making about organ quality has three main findings," the authors concluded. "First, many patients entered discussions about organ quality with an inherent bias against the acceptance of organs with higher risk of graft failure. Second, risk tolerance was highly variable between individuals and not particularly stable over time. Third, an individual patient's risk tolerance was associated with sex and beliefs about his or her control over his or her health, and not with the severity of liver disease."
The work was supported by the Robert Wood Johnson Foundation, the American Gastroenterological Association, and National Institutes of Health. No authors noted conflicts.
Primary source: Liver Transplantation
Source reference:
Volk ML, et al "Patient decision making about organ quality in liver transplantation" Liver Transpl 2011; 17: 1387-1393.
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