Liver transplant for the three predominant autoimmune liver diseases – primary biliary cholangitis, primary sclerosing cholangitis, and autoimmune hepatitis – has been known to have favorable outcomes overall, but little evidence comparing cholangitis and hepatitis exists. Now, researchers from Beth Israel Deaconess Medical Center in Boston have reported in the Journal of Clinical Gastroenterology that patients with autoimmune hepatitis have a higher risk of death despite a similar risk of disease recurrence.

The researchers analyzed results of 18,103 liver transplants from 1987 to 2016 in the United Network for Organ Sharing (UNOS) database, consisting of 4,153 for autoimmune hepatitis (AIH), 6,119 for primary biliary cholangitis (PBC), and 7,831 for primary sclerosing cholangitis (PSC).

“Our study indicates at least part of the increased posttransplant mortality in AIH may be due to a lower retransplant rate in this population,” said lead authors Jennifer Y. Lee, MD, and Christopher J. Danford, MD.

Median graft survival for the entire cohort was 14.3 years, but the AIH and PSC cohorts had significantly lower graft survival rates than the PBC patients, at 13.9 and 13.8 years, respectively, versus 14.8 years (P = .03).

“Differences between groups are apparent at 1 year, with a significant difference in 1-year graft survival between autoimmune disease,” the researchers noted, “with 82.2% survival for AIH, 83.2% for PBC, and 84% for PSC” (P = .04). However, the researchers said 30-day retransplant rates were similar between the groups: 3.2% for AIH, 3.5% for PBC, and 3.6% for PSC.

The differences between groups widened with time. At 5 years, graft survival was 70.9% for AIH, 74.4% for PBC, and 72.5% for PSC (P = .004); at 10 years, those rates were 56.3%, 63%, and 59.1%, respectively.

The study identified the following characteristics associated with a higher risk of graft failure: African American race; cold ischemia time; donor age; and Model for End-Stage Liver Disease (MELD) score at time of transplant. However, the authors noted that “the underlying causes leading to worse outcomes among AIH patients after liver transplant remain unclear.”

The AIH patients had higher average MELD scores at transplant and were more likely to be minorities, but even after adjustment for those factors, the AIH group had an increased risk of graft failure. Complication rates after transplant were also similar across groups, as evidenced by the 30-day retransplant rates. The study was also unable to evaluate disease recurrence within the UNOS database.

However, it’s those similar 30-day retransplant rates across the disease groups that may hold a clue of the disparate outcomes for AIH patients. The authors cited previous studies that reported disease recurrence and graft failure may explain the increased risk of death in AIH. That would imply retransplant rates perhaps should be higher, not similar, in the AIH group. “Future single-center studies would provide more granular data and potentially answer why AHI patients are not retransplanted,” they wrote.

The study authors have no financial relationships to disclose.

SOURCE: Lee JY et al. J Clin Gastroenterol. 2019 Oct 23. doi: 10.1097/MCG.0000000000001271.