How MELD 3.0 Is Bridging Sex-Based Liver Transplant Disparities: A Game Changer in Organ Allocation

SAN DIEGO — New research shows that the gender gap in liver transplants has decreased since the adoption of the MELD 3.0 scoring system by the Organ Procurement and Transplantation Network (OPTN) in July 2023.

Women are now more likely to be placed on the waitlist for liver transplants, more likely to receive a transplant, and less likely to die while on the waitlist.

“MELD 3.0 improved access to transplantation for women, and now waitlist mortality and transplant rates for women are closer to those for men,” said Allison Kwong, MD, the study’s lead author and a transplant hepatologist at Stanford Medicine.

Overall, transplant outcomes have improved year after year. Kwong presented these findings at The Liver Meeting 2024 of the American Association for the Study of Liver Diseases (AASLD).

Changes in MELD and Transplant Numbers

The MELD system estimates the severity of liver failure and short-term survival in patients with chronic liver disease. It has determined organ allocation priority since 2002. Initially, the score used three variables: creatinine, bilirubin, and the international normalized ratio (INR). In 2016, MELD 2.0 was introduced to include sodium.

Kwong noted that there were sex-based disparities under the previous system. Women received lower priority scores despite similar disease severity. Factors such as the creatinine measure and body size differences contributed to this issue. Men traditionally had a lower pretransplant mortality rate and higher transplant rates.

The MELD 3.0 system was developed to address these differences. It added 1.33 points for women, along with new variables like albumin and interactions between bilirubin, sodium, and creatinine to improve prediction accuracy.

Kwong and her team analyzed OPTN data from over 20,300 newly registered liver transplant candidates and about 18,700 transplant recipients, comparing data from the year before and after MELD 3.0’s implementation.

After MELD 3.0, 43.7% of candidates were women, compared to 40.4% before. The median age of patients at registration remained at 55, while the median MELD score slightly decreased from 23 to 22.

Post-implementation, the percentage of transplants among women rose to 42.1%, from 37.3% prior. Additionally, the 90-day waitlist dropout rate for women decreased from 13.5% to 9.1%. However, dropout rates for men also fell from 9.8% to 7.4%, likely due to advancements in technology, such as improved liver preservation methods.

Disparities Continue to Exist

Some disparities remain. The total median MELD score at the time of transplant decreased from 29 to 27, but women still had a higher median score of 29 compared to 27 for men.

“This indicates that there may still be differences in access to transplants between the sexes,” Kwong said. Body size differences affecting transplant eligibility are not addressed by MELD 3.0.

Future versions of MELD may consider these factors. “There are many potential versions of MELD,” Kwong noted. “It’s early to assess how MELD 3.0 will perform, but initial results are promising.”

Tamar Taddei, MD, a professor at Yale School of Medicine, emphasized the significance of using a MELD score that accounts for sex-based differences. She highlighted that MELD 3.0 reduces disparities previously faced by women in transplantation.

“It is encouraging to see both a reduction in disparities and a decrease in waitlist dropout for both sexes,” Taddei remarked. “This change makes sense.”

Kwong, Krag, and Taddei reported no conflicts of interest.

Carolyn Crist is a health journalist reporting on the latest studies for Medscape, MDedge, and WebMD.