Natural history of NASH cirrhosis in liver transplant waitlist registrants.

BACKGROUND AND AIMS

Non-alcoholic steatohepatitis (NASH) cirrhosis is rapidly growing as an indication for liver transplant(ation) (LT). However, the natural history of NASH cirrhosis among LT waitlist registrants has not been established. The present study aimed to define the natural history of NASH cirrhosis using the Scientific Registry of Transplant Recipients database.

METHODS

The study cohort comprised patients registered on the LT waitlist between 1/1/2016 to 12/31/2021. The primary outcomes included probability of LT and waitlist mortality, comparing NASH (n = 8,120) vs. non-NASH (n = 21,409) cirrhosis.

RESULTS

Patients with NASH cirrhosis were listed with lower model for end-stage liver disease (MELD) scores despite bearing a greater burden of portal hypertension, especially at lower MELD scores. The overall transplant probability in LT waitlist registrants with NASH [vs. non-NASH] cirrhosis was significantly lower at 90 days (HR 0.873, p <0.001) and 1 year (HR 0.867, p <0.001); this was even more pronounced in patients with MELD scores >30 (HR 0.705 at 90 days and HR 0.672 at 1 year, p <0.001 for both). Serum creatinine was the key contributor to MELD score increases leading to LT among LT waitlist registrants with NASH cirrhosis, while bilirubin was in patients with non-NASH cirrhosis. Finally, waitlist mortality at 90 days (HR 1.15, p <0.001) and 1 year (1.25, p <0.001) was significantly higher in patients with NASH cirrhosis compared to those with non-NASH cirrhosis. These differences were more pronounced in patients with lower MELD scores at the time of LT waitlist registration.

CONCLUSIONS

LT waitlist registrants with NASH cirrhosis are less likely to receive a transplant compared to patients with non-NASH cirrhosis. Serum creatinine was the major contributor to MELD score increases leading to LT in patients with NASH cirrhosis.

IMPACT AND IMPLICATIONS

This study provides important insights into the distinct natural history of non-alcoholic steatohepatitis (NASH) cirrhosis among liver transplant (LT) waitlist registrants, revealing that patients with NASH cirrhosis face lower odds of transplantation and higher waitlist mortality than those with non-NASH cirrhosis. Our study underscores the significance of serum creatinine as a crucial contributor to model for end-stage liver disease (MELD) score in patients with NASH cirrhosis. These findings have substantial implications, emphasizing the need for ongoing evaluation and refinement of the MELD score to more accurately capture mortality risk in patients with NASH cirrhosis on the LT waitlist. Moreover, the study highlights the importance of further research investigating the impact of the implementation of MELD 3.0 across the US on the natural history of NASH cirrhosis.