The hidden epidemic: Uncovering incidental fatty liver disease and its metabolic comorbidities by datamining in a hospital data lake - A real-world cohort study

Aims: To identify individuals with incidental fatty liver disease (FLD), and to evaluate its prevalence, metabolic co -morbidities and impact on follow-up. Methods: We leveraged the data -lake of Helsinki Uusimaa Hospital district (Finland) with a population of 1.7 million (specialist and primary care). A phrase recognition script on abdominal imaging reports (2008-2020) identified/excluded FLD or cirrhosis; we extracted ICD-codes, laboratory and BMI data. Results: Excluding those with other liver diseases, the prevalence of FLD was 29% (steatosis yes/no, N=61,271/ 155,521; cirrhosis, N=3502). The false positive and negative rates were 5-6%. Only 1.6% of the FLD cases had the ICD code recorded and 32% had undergone full clinical evaluation for associated co -morbidities. Of the 35-65 -year -old individuals with FLD, 20% had diabetes, 42% prediabetes and 28% a high liver fibrosis index. FLD was independently predicted by diabetes (OR 1.56, CI 1.46-1.66, p = 2.3 * 10"-41), BMI (1.46, 1.42-1.50, p = 1.7 * 10"-154) and plasma triglyceride level (1.5, 1.43-1.57, p = 3.5 * 10"-68). Alanine aminotransferase level mildly increased (1.12, 1.08-1.16, p = 2.2 * 10"-9) and high age decreased the risk (0.92, 0.89-0.94, p = 4.65*10"-09). Half of the cases had normal ALT. Conclusions: The incidental radiological finding of FLD is reliable and associated with metabolic risks but largely ignored, although it should lead to metabolic and hepatic follow-up.