OBJECTIVES: This study aimed to evaluate the impact of adjusting a Markov cohort model for nonalcoholic steatohepatitis (NASH) based on recent literature findings.

METHODS: A previously developed Markov cohort model for NASH was updated based on recent studies. The model adjustments involved splitting two early fibrosis stages into six separate health states and adapting the model inputs. The performance of the updated model was assessed and validated against the ICER US model, which compared small molecule and lifestyle interventions. Additionally, the inclusion of health states not considered by ICER US corresponding to non-alcoholic fatty liver (NAFL) and the cost-effectiveness potential of theoretical NASH treatments, such as biologic and curative therapies, were explored.

RESULTS: The incremental quality-adjusted life years (QALYs) between small molecule and lifestyle interventions were similar between our model and the ICER US model (0.70 vs. 0.61). The slight difference may be attributed to the lack of inclusion of cardiovascular events in our model. When considering the possibility of regression towards NAFL in the early fibrosis stages, our model estimated a much lower difference in QALYs between small molecule and lifestyle interventions (0.20). Despite the increased accumulation of the simulated cohort in the early stages of fibrosis, the incremental total QALYs reached 0.31 for biologic therapy and 1.58 for curative therapy compared to lifestyle intervention.

CONCLUSIONS: Extending the number of health states to capture early disease stages yielded more robust results and provided a more conservative approach. The updated model inputs improved the potential cost-effectiveness of theoretical therapies for NASH. Inclusion of NAFL health states in the model and exploring alternative treatment options further enhanced the understanding of NASH management strategies.