Non-invasive fibrosis scores are widely used to identify/exclude advanced fibrosis in patients with non-alcoholic fatty liver disease (NAFLD).
However, these scores were principally developed and validated in patients aged between 35 and 65 years of age.
Dr Stuart McPherson and colleagues from the United Kingdom assessed the effect of age on the performance of non-invasive fibrosis tests in NAFLD.
Patients were recruited from European specialist hepatology clinics.
The cohort was divided into 5 age-based groups, including ≤35, 36–45, 46–55, 56–64, and ≥65 years.
The team assessed the performance of the aspartate aminotransferase (AST)/alanine transaminase (ALT) ratio, fibrosis 4 (FIB-4), and NAFLD fibrosis score for advanced fibrosis (stage F3–F4) for each group using liver biopsy as the standard.
The researchers evaluated 634 patients.
|New cutoffs for those aged ≥65 years improved specificity to 70%|
|American Journal of Gastroenterology|
The diagnostic accuracy of the AST/ALT ratio was lower than NAFLD fibrosis score and FIB-4 in all the age groups.
The AST/ALT ratio, NAFLD fibrosis score , and FIB-4 score performed poorly for a diagnosis of advanced fibrosis in those aged ≤35 years.
For all groups >35 years, the team found that area under the received of operating characteristic curves for advanced fibrosis were similar for the NAFLD fibrosis score and FIB-4 score.
The researchers observed that the specificity for advanced fibrosis using the FIB-4 and NAFLD fibrosis score declined with age, becoming unacceptably low in those aged ≥65 years.
The team derived new cutoffs for those aged ≥65 years, which improved specificity to 70% without adversely affecting sensitivity.
Dr McPherson's team concludes, "The NAFLD fibrosis score and FIB-4 scores have similar accuracy for advanced fibrosis in patients aged >35 years."
"However, the specificity for advanced fibrosis is unacceptably low in patients aged ≥65 years, resulting in a high false positive rate."
"New thresholds for use in patients aged ≥65 years are proposed to address this issue."