Modelling the cost effectiveness of non-alcoholic fatty liver disease risk stratification strategies in the community setting

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is highly prevalent worldwide. Identifying high-risk patients is critical to best utilize limited health care resources. We established a community-based care pathway using 2D ultrasound shear wave elastography (SWE) to identify high risk patients with NAFLD. Our objective was to assess the cost-effectiveness of various non-invasive strategies to correctly identify high-risk patients.

METHODS

A decision-analytic model was created using a payer's perspective for a hypothetical patient with NAFLD. FIB-4 [≥1.3], NAFLD fibrosis score (NFS) [≥-1.455], SWE [≥8 kPa], transient elastography (TE) [≥8 kPa], and sequential strategies with FIB-4 or NFS followed by either SWE or TE were compared to identify patients with either significant (≥F2) or advanced fibrosis (≥F3). Model inputs were obtained from local data and published literature. The cost/correct diagnosis of advanced NAFLD was obtained and univariate sensitivity analysis was performed.

RESULTS

For ≥F2 fibrosis, FIB-4/SWE cost $148.75/correct diagnosis while SWE cost $276.42/correct diagnosis, identifying 84% of patients correctly. For ≥F3 fibrosis, using FIB-4/SWE correctly identified 92% of diagnoses and dominated all other strategies. The ranking of strategies was unchanged when stratified by normal or abnormal ALT. For ≥F3 fibrosis, the cost/correct diagnosis was less in the normal ALT group.

CONCLUSIONS

SWE based strategies were the most cost effective for diagnosing ≥F2 fibrosis. For ≥F3 fibrosis, FIB-4 followed by SWE was the most effective and least costly strategy. Further evaluation of the timing of repeating non-invasive strategies are required to enhance the cost-effective management of NAFLD.

Cost-effectiveness of enhanced liver fibrosis test to assess liver fibrosis in chronic hepatitis C virus and alcoholic liver disease patients

AIM

To assess liver fibrosis (LF) in hepatitis C virus (HCV) and alcoholic liver disease (ALD), estimate health outcomes and costs of new noninvasive testing strategies

METHODS

A Markov model was developed to simulate LF progression in HCV and ALD for a cohort of 40-year-old men with abnormal levels of transaminases. Three different testing alternatives were studied: a single liver biopsy; annual Enhanced liver fibrosis (ELF™) followed by liver stiffness measurement (LSM) imaging as a confirmation test if the ELF test is positive; and annual ELF test without LSM. The analysis was performed from the perspective of a university hospital in Spain. Clinical data were obtained from published literature. Costs were sourced from administrative databases of the hospital. Deterministic and probabilistic sensitivity analyses were performed.

RESULTS

In HCV patients, annual sequential ELF test/LSM and annual ELF test alone prevented respectively 12.9 and 13.3 liver fibrosis-related deaths per 100 persons tested, compared to biopsy. The incremental cost-effectiveness ratios (ICERs) were respectively €13400 and €11500 per quality-adjusted life year (QALY). In ALD, fibrosis-related deaths decreased by 11.7 and 22.1 per 100 persons tested respectively with sequential ELF test/LSM and annual ELF test alone. ICERs were €280 and €190 per QALY, respectively.

CONCLUSION

The use of the ELF test with or without a confirmation LSM are cost-effective options compared to a single liver biopsy for testing liver fibrosis in HCV and ALD patients in Spain.

Non-invasive assessment of liver fibrosis: Between prediction/prevention of outcomes and cost-effectiveness

The assessment of the fibrotic evolution of chronic hepatitis has always been a challenge for the clinical hepatologist. Over the past decade, various non-invasive methods have been proposed to detect the presence of fibrosis, including the elastometric measure of stiffness, panels of clinical and biochemical parameters, and combinations of both methods. The aim of this review is to analyse the most recent data on non-invasive techniques for the evaluation of hepatic fibrosis with particular attention to cost-effectiveness. We searched for relevant studies published in English using the PubMed database from 2009 to the present. A large number of studies have suggested that elastography and serum markers are useful techniques for diagnosing severe fibrosis and cirrhosis and for excluding significant fibrosis in hepatitis C virus patients. In addition, hepatic stiffness may also help to prognosticate treatment response to antiviral therapy. It has also been shown that magnetic resonance elastography has a high accuracy for staging and differentiating liver fibrosis. Finally, studies have shown that non-invasive methods are becoming increasingly precise in either positively identifying or excluding liver fibrosis, thus reducing the need for liver biopsy. However, both serum markers and transient elastography still have “grey area” values of lower accuracy. In this case, liver biopsy is still required to properly assess liver fibrosis. Recently, the guidelines produced by the World Health Organization have suggested that the AST-to-platelet ratio index or FIB-4 test could be utilised for the evaluation of liver fibrosis rather than other, more expensive non-invasive tests, such as elastography or FibroTest.

Transient Elastography and Controlled Attenuation Parameter for Diagnosing Liver Fibrosis and Steatosis in Ontario: An Economic Analysis

BACKGROUND

Liver fibrosis is characterized by a buildup of connective tissue due to chronic liver damage. Steatosis is the collection of excessive amounts of fat inside liver cells. Liver biopsy remains the gold standard for the diagnosis of liver fibrosis and steatosis, but its use as a diagnostic tool is limited by its invasive nature and high cost.

OBJECTIVES

To evaluate the cost-effectiveness and budget impact of transient elastography (TE) with and without controlled attenuation parameter (CAP) for the diagnosis of liver fibrosis or steatosis in patients with hepatitis B, hepatitis C, alcoholic liver disease, and nonalcoholic fatty liver disease.

DATA SOURCES

An economic literature search was performed using computerized databases. For primary economic and budget impact analyses, we obtained data from various sources, such as the Health Quality Ontario evidence-based analysis, published literature, and the Institute for Clinical Evaluative Sciences.

REVIEW METHODS

A systematic review of existing TE cost-effectiveness studies was conducted, and a primary economic evaluation was undertaken from the perspective of the Ontario Ministry of Health and Long-Term Care. Decision analytic models were used to compare short-term costs and outcomes of TE compared to liver biopsy. Outcomes were expressed as incremental cost per correctly diagnosed cases gained. A budget impact analysis was also conducted.

RESULTS

We included 10 relevant studies that evaluated the cost-effectiveness of TE compared to other noninvasive tests and to liver biopsy; no cost-effectiveness studies of TE with CAP were identified. All studies showed that TE was less expensive but associated with a decrease in the number of correctly diagnosed cases. TE also improved quality-adjusted life-years in patients with hepatitis B and hepatitis C. Our primary economic analysis suggested that TE led to cost savings but was less effective than liver biopsy in the diagnosis of liver fibrosis. TE became more economically attractive with a higher degree of liver fibrosis. TE with CAP was also less expensive and less accurate than liver biopsy.

LIMITATIONS

The model did not take into account long-term costs and consequences associated with TE and liver biopsy and did not include costs to patients and their families, or patient preferences related to diagnostic information.

CONCLUSIONS

TE showed potential cost savings compared to liver biopsy. Further investigation is needed to determine the long-term impacts of TE on morbidity and mortality in Canada and the optimal diagnostic modality for liver fibrosis and steatosis.

Ultrasound elastography for fibrosis surveillance is cost effective in patients with chronic hepatitis C virus in the UK

BACKGROUND

Chronic hepatitis C (HCV) is a significant risk factor for cirrhosis and subsequently hepatocellular carcinoma (HCC). HCV patients with cirrhosis are screened for HCC every 6 months. Surveillance for progression to cirrhosis and consequently access to HCC screening is not standardized. Liver biopsy, the usual test to determine cirrhosis, carries a significant risk of morbidity and associated mortality. Transient ultrasound elastography (fibroscan) is a non-invasive test for cirrhosis.

PURPOSE

This study assesses the cost effectiveness of annual surveillance for cirrhosis in patients with chronic HCV and the effect of replacing biopsy with fibroscan to diagnose cirrhosis.

METHOD

A Markov decision analytic model simulated a hypothetical cohort of 10,000 patients with chronic HCV initially without fibrosis over their lifetime. The cirrhosis surveillance strategies assessed were: no surveillance; current practice; fibroscan in current practice with biopsy to confirm cirrhosis; fibroscan completely replacing biopsy in current practice (definitive); annual biopsy; annual fibroscan with biopsy to confirm cirrhosis; annual definitive fibroscan.

RESULTS

Our results demonstrate that annual definitive fibroscan is the optimal strategy to diagnose cirrhosis. In our study, it diagnosed 20 % more cirrhosis cases than the current strategy, with 549 extra patients per 10,000 accessing screening over a lifetime and, consequently, 76 additional HCC cases diagnosed. The lifetime cost is £98.78 extra per patient compared to the current strategy for 1.72 additional unadjusted life years. Annual fibroscan surveillance of 132 patients results in the diagnosis one additional HCC case over a lifetime. The incremental cost-effectiveness ratio for an annual definitive fibroscan is £6,557.06/quality-adjusted life years gained.

CONCLUSION

Annual definitive fibroscan may be a cost-effective surveillance strategy to identify cirrhosis in patients with chronic HCV, thereby allowing access of these patients to HCC screening.

[Evaluation of the costs of transient elastography (FibroScan(®)) in the diagnosis of liver fibrosis in HIV patients with hepatitis C virus]

INTRODUCTION

The assessment of liver fibrosis is crucial for taking therapeutic decisions in patients infected with HIV/AIDS coinfected with HCV, because it allows the prognosis of the disease and the prioritization of hepatitis C treatment in these patients.

METHODS

A discrete events model simulation (DEMS) and a Markov model have been developed to represent the evolution of liver fibrosis to cirrhosis in patients coinfected with HIV/HVC. The model evaluated two alternatives for the diagnosis and monitoring of these patients, transient elastography performed annually and liver biopsy performed every seven years. The models have been developed under Health Care System perspective and only considered direct medical costs (disease treatment and health state costs). One-way sensitivity analyses were carried out to assess the impact of parameters with higher uncertainty. A discount rate of 3% was applied.

RESULTS

Base case analysis shows that the diagnosis and monitoring of patients with transient elastography is a dominant strategy compared with to liver biopsy, resulting in greater life expectancy at lower cost. The sensitivity analysis performed confirmed the robustness of these results.

CONCLUSION

Transient elastography has proved to be a dominant strategy compared to liver biopsy in the diagnosis and monitoring of liver fibrosis in patients coinfected with HIV/HCV in Spain.