Economic evaluation of a community-based diagnostic pathway to stratify adults for non-alcoholic fatty liver disease: a Markov model informed by a feasibility study

Abstract

Objectives: To assess the long-term cost-effectiveness of a risk stratification pathway, compared with standard care, for detecting non-alcoholic fatty liver disease (NAFLD) in primary care.

Setting: Primary care general practices in England.

Participants: Adults who have been identified in primary care to have a risk factor for developing NAFLD, that is, type 2 diabetes without a history of excessive alcohol use.

Intervention: A community-based pathway, which uses transient elastography and hepatologists to stratify patients at risk of NAFLD, has been implemented and demonstrated to be feasible (NCT02037867). Earlier identification could mean earlier treatments, referral to specialist and enrolment into surveillance programmes.

Design: The impact of earlier detection and treatment with the risk stratification pathway on progression to later stages of liver disease was examined using decision modelling with Markov chains to estimate lifetime health and economic effects of the two comparators.

Data sources: Data from a prospective cross-sectional feasibility study indicating risk stratification pathway and standard care diagnostic accuracies were combined with a Markov model that comprised the following states: no/mild liver disease, significant liver disease, compensated cirrhosis, decompensated cirrhosis, hepatocellular carcinoma, liver transplant and death. The model data were chosen from up-to-date UK sources, published literature and an expert panel.

Outcome measure: An incremental cost-effectiveness ratio (ICER) indicating cost per quality-adjusted life year (QALY) of the risk stratification pathway compared with standard care was estimated.

Results: The risk stratification pathway was more effective than standard care and costs £2138 per QALY gained. The ICER was most sensitive to estimates of the rate of fibrosis progression and the effect of treatment on reducing this, and ranged from -£1895 to £7032/QALY. The risk stratification pathway demonstrated an 85% probability of cost-effectiveness at the UK willingness-to-pay threshold of £20 000/QALY.

Conclusions: Implementation of a community-based risk stratification pathway is likely to be cost-effective.

Trial registration number: NCT02037867, ClinicalTrials.gov.

Keywords: cost effectiveness analysis; fibrosis; quality-adjusted life-years; screening; transient elastography.

Conflict of interest statement

Competing interests: None declared.

© Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Figures

Figure 1

Decision tree and Markov model for the economic evaluation of risk stratification pathway in non-alcoholic fatty liver disease. Markov model states: NMD, no/mild disease: a patient can be identified (NMD+) or not identified (NMD−) to be at risk of developing disease; SLD, significant liver disease: a patient can be diagnosed (SLD+) or not (SLD−); CC, compensated cirrhosis: a patient can be diagnosed (CC+) or not (CC−); DC, decompensated cirrhosis; HCC, hepatocellular carcinoma; LT, liver transplant. Death possible from every state.

Figure 2

Probabilistic sensitivity analysis: cost-effectiveness plane and cost-effectiveness acceptability curve for risk stratification pathway versus standard care.

Figure 3

Tornado diagram. CC, compensated cirrhosis; CCI, compensated cirrhosis Baveno stage I; CCII, compensated cirrhosis Baveno stage II; DC, decompensated cirrhosis; DCIII, decompensated cirrhosis Baveno stage III; HCC, hepatocellular carcinoma; ICER, incremental cost-effectiveness ratio; NMD, no/mild disease; QALY, quality-adjusted life year; RR, relative risk; RSP, risk stratification pathway; SLD, significant liver disease.