Can we use metabolic risk factors to predict significant liver disease in primary care?

Problem

Mortality from liver disease is increasing in the UK, with an average age of death of 59 it is a leading cause of premature mortality. Up to three quarters of people with liver disease present for the first time when they have irreversible cirrhosis, and intervention is less effective. Earlier detection of liver disease in primary care would allow intervention to prevent progression. Non-alcoholic Fatty Liver Disease (NAFLD) is associated with metabolic risk factors making up the metabolic syndrome. We routinely collect information on these metabolic risk factors in primary care. This research will synthesise evidence on the use of metabolic risk factors to predict which patients with NAFLD will go on to develop significant liver disease (NASH, fibrosis, cirrhosis, liver mortality). This will allow targeting of fibrosis testing and intervention.

Approach

A systematic review is being conducted of published evidence looking at metabolic risk factors as predictive or prognostic factors in the development of significant liver disease. The search strategy is based on a similar review carried out by NICE in 2015 for their 2016 NAFLD guidelines, updated and expanded to include a broader range of liver outcomes and study designs. Searches have been conducted in MEDLINE, EMBASE, The Cochrane Library and clinical trials.gov. Additional grey literature has been searched on CPCI-S (Conference Proceedings Citation Index) and OpenGrey. Citation searches were also carried out.Titles and abstracts of all identified studies were screened independently by two review authors. The full text of potentially eligible studies were retrieved and independently assessed for eligibility by two review team members.

Findings

6,946 records were identified for title and abstract screening. 263 met criteria for full text screening, and 40 papers reporting on 28 cohort studies have been selected for inclusion. Data extraction is underway and results will be available for presentation at conference in July. Preliminary results based on full text screening indicate that there is a significant body of evidence around the utility of metabolic risk factors in helping to predict significant future liver disease, with the majority of evidence focused around markers of obesity and insulin resistance as predictors of poor outcomes.

Consequences

The results of this systematic review will bring together the published evidence around metabolic risk and liver outcomes. This will allow primary care clinicians and policy makers to make evidence based decisions on which of the many people with fatty liver should be investigated and kept under regular review. My review alongside other ongoing work will provide the impetus for a ‘liver health check’ to be added to chronic disease management for people at increased risk, and contribute to earlier detection and mortality reduction for people with liver disease.