NAFLD is defined as the presence of accumulated fat in the liver (hepatic steatosis) in more than 5% of hepatocytes, absence of significant alcohol consumption, viral infection, or other specific causes of liver disease.

NAFLD is further categorized into non-alcoholic fatty liver (NAFL) and non-alcoholic steatohepatitis (NASH).

Moreover, NAFLD can lead to fibrosis and cirrhosis of the liver, being one of the main reasons for liver transplantation in patients.

NASH is the more severe stage of this disease, where, according to various studies, 10-29% of cases will develop liver cirrhosis within 10 years of diagnosis. Furthermore, 20-30% of these cases will develop hepatocellular carcinoma.

NASH and NAFLD are common diseases in industrialized countries. According to a recent meta-analysis, the prevalence of the disease is estimated to be 23.71% in Europe, with the rate varying from country to country, ranging from 5% to 44%.

The etiology of NAFLD/NASH is multifactorial. Over the years, it has become increasingly evident that an individual's susceptibility to developing a disease depends on the interaction of environmental factors with genetic and metabolomic factors, respectively, which play a key role in the pathogenesis and progression of NAFLD.

The majority of patients with NAFLD do not develop symptoms, therefore the disease is considered asymptomatic and its diagnosis is often made incidentally. However, to date, no method with high diagnostic value has been developed, resulting in the direct risk of falsely positive or negative results.

This is due to the fact that the available methods do not proceed to diagnosis and prognosis taking into account different types of data.

Given that the genetic and metabolomic profile, as well as the lifestyle of individuals, play a significant role in the onset of NAFLD, the need to develop a new diagnostic and prognostic algorithm - with high sensitivity and specificity - that includes all these factors, becomes imperative.

THE OBJECTIVES OF THE PRESENT STUDY

1.To analyze lifestyle data in relation to the disease, in the Hellenic NAFLD Study population study, with the aim of creating a lifestyle index.

2.To obtain metabolomic data for the Hellenic NAFLD Study population study, which belongs to the biobank of the coordinator's laboratory.

3.To analyze the genetic and metabolomic data of the Hellenic NAFLD Study, aiming to find potential diagnostic biomarkers.

4.To create a polygenic risk score (PRS) for NAFLD in the UK Biobank and to validate it in the Hellenic NAFLD Study population study.

5.To develop, test, and optimize appropriate algorithms characterized by high sensitivity and specificity for the diagnosis and prognosis of the disease.

Research Entity: Harokopio University of Athens, Department of Dietetics - Nutrition

Private Entity: ACTIVE SOCIAL NETWORKING (ASN) Company