Scoring System Rates Kidney Transplant Program Quality
MIAMI BEACH—Researchers have created a quality indicator that allows comparisons of different transplant centers.
Regulatory agencies have made public transplant outcomes data such as patient and graft survival as well as length of hospital stay, and other factors such as transplant center level of organ sharing and use of organs from donors older than age 65. Centers are regulated and disciplined based mainly on survival data.
At the American Society of Transplant Surgeons' 13th Annual State of the Art Winter Symposium, a team from the Hartford Hospital in Hartford, Conn., showcased its quality index (QI), which is a simple formula that takes into account patient and graft survival as well as transplant rate. They found that centers with higher QI scores successfully balance a healthy amount of organ sharing with keeping the odds as high as possible for good transplant outcomes.
Facilities with higher QI scores had higher rates of organ sharing than lower-QI centers and longer lengths of stay, but also lower rates of use of organs from donors above age 65, and slightly lower rates of delayed graft function.
“Having a good QI reflects a good balance of organ sharing—accepting riskier organs that other centers have turned down—and watching graft and patient survival rates, so not taking everything you are being offered,” lead investigator Caroline Rochon, MD, told Renal & Urology News. “But our QI also gives lower scores to centers that only use perfect 'no-risk' organs that result in great patient and graft survival but lower transplant rates and therefore long wait times for transplantation.”
The formula for the new QI is: (observed patient survival/expected patient survival) × (0.7 if patient-survival ratio is less than 1, 1 if it is equal to 1, and 1.3 if the ratio is above 1) × (observed graft survival/expected graft survival) × (0.7, 1 or 1.3) × (observed transplant rate/expected transplant rate). This formula goes beyond patient and graft survival, which are central in the Centers for Medicare & Medicaid Services (CMS) and the United Network for Organ Sharing (UNOS) determination of program performance.
Dr. Rochon said her team chose the factors of 0.7, 1.0, and 1.3 arbitrarily. The most important point, however, is that the formula reduces scores for programs that are below the expected performance in key parameters, including transplant rate, she said.
The team analyzed Scientific Registry of Transplant Recipients data from 40 kidney transplant programs randomly selected from across the United States. The median QI value from these centers was 1.06 (range 0.33-3.68). The researchers observe that major academic centers—that is, those that produced at least three publications in 2012—did not have higher QI than non- academic ones. Nor was there a significant difference in the average QIs of centers that did at least 150 kidney transplants in 2012 and lower-volume facilities.
The study also revealed a non-significant difference in the rate of delayed graft function between programs with a QI of greater than 0.8 and less than 0.8 (25% and 30%, respectively). Yet the average QI was 0.87 among centers with a median length of stay of less than five days and 1.33 among centers with an average length of stay longer than five days.
“The longer hospital stays may be the consequence of a ‘non-cherry-picking' practice on the part of higher-QI centers, where sicker patients get transplanted and their level of physical deconditioning, malnutrition and cardiac comorbidities impact their length of stay,” Dr. Rochon and her co-investigators noted in a poster presentation of the results.
The average QI of programs that had greater than 25% organ sharing was 1.4, while it was 1.1 for programs that imported a smaller proportion of their kidneys, but this difference was not statistically significant. The difference in the rates of organ sharing between centers with a QI of more than or less than 0.8, was significant at 27% and 15%, respectively. Among higher-QI programs, however, the proportion of organs from donors over age 65 was 2%, compared with 5.6% for higher-QI centers.
Dr. Rochon said she next plans to compare the demographics and comorbidities of patients from lower- and higher-QI programs. She and her team have also designed a similar QI for liver-transplant programs.