Cost-effectiveness of MRE versus VCTE in staging fibrosis for nonalcoholic fatty liver disease (NAFLD) patients with advanced fibrosis

Abstract

Introduction: NAFLD is a common cause of liver disease. To determine the optimal testing strategy for NAFLD patients with advanced fibrosis, several factors such as diagnostic accuracy, failure rates, costs of examinations, and potential treatment options need to be considered. The purpose of this study was to determine the cost-effectiveness of combination testing involving vibration-controlled transient elastography (VCTE) versus magnetic resonance elastography (MRE) as a frontline imaging strategy for NAFLD patients with advanced fibrosis.Methods: A Markov model was developed from the US perspective. The basecase scenario in this model included patients aged 50 years with a Fibrosis-4 score of ≥ 2.67 and suspected advanced fibrosis. The model included a decision tree and a Markov state-transition model including 5 health states: fibrosis stage 1-2, advanced fibrosis, compensated cirrhosis, decompensated cirrhosis, and death. Both deterministic and probabilistic sensitivity analyses were performed. Results: Staging fibrosis with MRE cost $8388 more than VCTE but led to an additional 1.19 Quality-adjusted life years (QALYs) with the incremental cost-effectiveness ratio of $7048/QALY. The cost-effectiveness analysis of the 5 strategies revealed that MRE+biopsy and VCTE+MRE+biopsy were the most cost-effective with the incremental cost-effectiveness ratios of $8054/QALY and $8241/QALY, respectively. Furthermore, sensitivity analyses indicated that MRE remained cost-effective with a sensitivity of ≥ 0.77, whereas VCTE became cost-effective with a sensitivity of ≥ 0.82. Conclusions: MRE was not only cost-effective than VCTE as the frontline modality for staging NAFLD patients with Fibrosis-4 ≥ 2.67 with incremental cost-effectiveness ratio of $7048/QALY but also remained cost-effective when used as a follow-up in instances of VCTE failure to diagnose.

Reply: Is lifestyle modification effective for individuals with high fibrosis-4 index without an additional second-tier test?

“…This is included within the model although we do not have a separate comparator arm that compares intensive lifestyle intervention only. In this model, we assume the following: Advanced fibrosis patients will receive the lifestyle program As part of the lifestyle intervention program, the regression of fibrosis was estimated at 19% per arm (Reference #36 1 ). As explained in our previous response to “Modeling concerns,” while the average age of the patient in the model is 50 years old, the patient life span is modeled based on CDC, National Vital Statistics Reports life tables for the US population.…”

“…In fact, the probability of dying at age 100 is 1. (Please refer to our response to Dr Tapper’s letter) The differential in the effectiveness is dependent on the difference between the 2 comparators vis-à-vis the ability to diagnose and the sensitivity and specificity of MRE and VCTE. A spontaneous regression that appeared regardless of treatment is the value shown in Table 2, 1 while the rate of regression due to the lifestyle modification program was only applied to the treatment group. The regression rate for the treatment group was calculated by using spontaneous regression as the base and adding a modifier of 19% to this base rate.…”

“…As part of the lifestyle intervention program, the regression of fibrosis was estimated at 19% per arm (Reference #36 1 ).…”

“…A spontaneous regression that appeared regardless of treatment is the value shown in Table 2, 1 while the rate of regression due to the lifestyle modification program was only applied to the treatment group. The regression rate for the treatment group was calculated by using spontaneous regression as the base and adding a modifier of 19% to this base rate.…”

Reply: Modeling concerns

“…As you stated, in practice, all patients may receive the lifestyle modification program at any stage. However, in the model, we assume that only patients identified as positive for advanced fibrosis will receive the lifestyle program as part of an intervention and regression of fibrosis was estimated at 19% per arm 1 Lastly, within the MRE arm, the TP (83%) and FP (17%) received the lifestyle modification Within the VCTE arm, the TP (77%) and FP (22%) received the lifestyle modification 1 We agree that the assumption of prevalence of FIB4 > 2.67 to be 80% might be on the high side.…”