Chronic liver disease after allogeneic hematopoietic cell transplantation.

Background Aims: There are few descriptions of the epidemiology of chronic liver disease (CLD) after allogeneic hematopoietic stem cell transplantation (allo-HCT). Among those transplanted before 2000, viral hepatitis was the dominant cause of CLD. Recently, the prevalence of metabolic dysfunction-associated steatotic liver disease (MASLD, previously known as nonalcoholic fatty liver disease) is increasing in the general population. In addition, survivors of allo-HCT are known to be at increased risk of metabolic syndrome. We set out to describe the epidemiology of CLD in a modern cohort of allo-HCT recipients. We hypothesized that MASLD would be the most common cause of CLD in the cohort.

Methods: We undertook a retrospective cohort and nested case-control study of 2-year survivors of allo-HCT in Alberta transplanted between 2008 and 2018.

Results: Among 392 2-year survivors of allo-HCT between 2008 and 2018, the prevalence of CLD was 41.8% and MASLD was identified in 56% of those with CLD, followed by iron overload in 47% of those with CLD. The prevalence of MASLD among the entire cohort was 46%. Although most patients developed CLD before 2 years post-transplant, there was a 13% cumulative incidence of new CLD after 2 years posttransplant. Grade 2-4 acute graft-versus-host disease and/or moderate-to-severe chronic graft-versus-host disease and pretransplant CLD were strongly associated with CLD. In the case-control study examining the association between cardiovascular risk factors and CLD, type 2 diabetes was associated with CLD. Cirrhosis developed in 1.5% of survivors, and MASLD was an underlying etiology in one half of these cases. There was no difference in overall survival and non-relapse mortality between those who did and did not develop CLD.

Conclusions: MASLD is the main cause of CLD in recent long-term survivors of allo-HCT and may be associated with post-transplant corticosteroid exposure and type 2 diabetes. We note a shift in the underlying etiology of CLD post-HCT: previous studies describe viral hepatitis as the most common cause of CLD. The high prevalence of MASLD in allo-HCT recipients has important implications for survivorship care.