Reducing NAFLD-Screening Time: A Comparative Study of Eight Diagnostic Methods Offering an Alternative to Ultrasound Scans

Filippo Procino; Giovanni Misciagna; Nicola Veronese; Maria G. Caruso; Marisa Chiloiro; Anna M. Cisternino; Maria Notarnicola; Caterina Bonfiglio; Irene Bruno; Claudia Buongiorno; Angelo Campanella; Valentina Deflorio; Isabella Franco; Rocco Guerra; Carla M. Leone; Antonella Mirizzi; Alessandro Nitti; Alberto R. Osella; MICOL GROUP


Liver International. 2019;39(1):187-196. 

In This Article


Non-alcoholic fatty liver disease (NAFLD) is currently the leading cause of chronic liver disease in Western countries, as well as a condition of increased risk for cardiovascular disease, type 2 diabetes mellitus, chronic renal disease and increased mortality for non-hepatic causes compared to the unaffected population.[1–5]

This condition is defined as the accumulation of triglycerides in hepatocytes (>5% of the total liver weight) of a patient with reduced alcohol intake (<30 g per day in males or <20 g per day in females) after excluding viral infection, or other specific liver diseases.[6]

It may manifest as a pure fatty liver (hepatosteatosis) or as non-alcoholic steatohepatitis (NASH), an evolution of the former when the steatosis is associated with inflammation and hepatocellular injury, and with fibrogenic activation that can lead to cirrhosis and the onset of hepatocarcinoma.[7]

The global prevalence of NAFLD is currently estimated to be 24% and is continuously rising (15% in 2005% to 25% in 2010). A meta-analysis published in 2016 reported an average prevalence of 23.71% in Europe.[8] Our studies, conducted in the population of Castellana Grotte and Putignano (district of Bari—Puglia—Italy), registered a NAFLD frequency of about 30%, with a prevalence in male subjects and older patients.[9,10]

The NAFLD risk is related to many conditions. Measuring liver enzymes is insufficient since only 54% of NAFLD cases occur in patients with elevated serum alanine aminotransferase (ALT) levels. The vast majority of patients with NAFLD show many metabolic syndrome features.[11–13] Likewise, data from a UK study suggest that NAFLD detected ultrasonographically is present in 42.6% of patients with type 2 diabetes (T2DM).[14] The prevalence of NAFLD also increases with the body mass index (BMI); indeed, in an Italian study 91% of obese patients (BMI ≥ 30 kg/m2) vs 25% of normal weight individuals (BMI 18–25 kg/m2) had ultrasonographic evidence of NAFLD.[15,16]

The prevalence of NAFLD depends strictly on the type of diagnostic methods used. According to the recent EASL-EASD-EASO guidelines, the gold standard to identify steatosis in individual patients is magnetic resonance imaging (MRI), but ultrasound scanning (US) is preferable because it is more widely available and cheaper than MRI. However, for large-scale screening studies, serum biomarkers are preferred, as the availability and cost of imaging substantially impact screening feasibility.[17] Among the steatosis scores, one of the best validated is the Fatty Liver Index (FLI).[18]

Some studies suggest that other scores or anthropometric measures (anthro-m) work as the FLI in predicting the NAFLD risk.[19–23] Aims of this study were first to analyze the performance of 8 different scores and anthro-m (formulas) in identifying people with NAFLD; second to evaluate which factors most strongly affect the performance of each formula; third to find the best cut-offs and to assess the optimal cut-offs of each factor in our population, taking care to include any critical discriminant factors. Finally, to compare the performance of 8 alternative hybrid in a large population by using the predictive formulas as first filter strategy, and then performing US in subjects predicted as at risk.