From the Guidelines
Hepatic steatosis, also known as fatty liver disease, is a condition characterized by the abnormal accumulation of fat in liver cells, defined as the presence of excess triglyceride storage in the liver in the presence of at least one cardiometabolic risk factor, as stated in the 2024 EASL-EASD-EASO clinical practice guidelines 1.
Definition and Classification
Hepatic steatosis can be categorized into different conditions, including isolated liver steatosis, metabolic dysfunction-associated steatohepatitis (MASH), and fibrosis and cirrhosis. The term MASLD replaces the old term non-alcoholic fatty liver disease (NAFLD) and is embedded in the new consensus definition of steatotic liver disease (SLD) 1.
Risk Factors and Symptoms
Risk factors for hepatic steatosis include obesity, diabetes, high cholesterol, metabolic syndrome, and certain medications. Many people with hepatic steatosis have no symptoms, though some may experience fatigue, abdominal discomfort, or a feeling of fullness in the upper right side of the abdomen.
Diagnosis and Treatment
Diagnosis of hepatic steatosis involves non-invasive tests, such as blood-based scores (e.g., FIB-4) and imaging techniques (e.g., transient elastography), to rule out advanced fibrosis, which is predictive of liver-related outcomes 1. Treatment typically involves lifestyle modifications, such as weight loss through diet and exercise, avoiding alcohol, managing underlying conditions like diabetes and high cholesterol, and in some cases, medication to address specific aspects of the disease.
Management and Prevention
Management of MASLD includes case-finding strategies, lifestyle modification, optimal management of comorbidities, and consideration of bariatric surgery in individuals with MASLD and obesity 1. The liver has remarkable regenerative capabilities, and early-stage fatty liver can often be reversed with appropriate interventions. Early identification and treatment of hepatic steatosis are crucial to prevent progression to inflammation, fibrosis, cirrhosis, or even liver failure in severe cases, as emphasized in the 2024 EASL-EASD-EASO clinical practice guidelines 1. Some key points to consider in the management of hepatic steatosis include:
- Lifestyle modification, including weight loss, dietary changes, physical exercise, and discouraging alcohol consumption
- Optimal management of comorbidities, including use of incretin-based therapies for type 2 diabetes or obesity
- Consideration of bariatric surgery in individuals with MASLD and obesity
- Use of non-invasive tests to rule out advanced fibrosis and predict liver-related outcomes
- Early identification and treatment to prevent progression to severe liver disease.
From the Research
Definition of Hepatic Steatosis
Hepatic steatosis, also known as fatty liver disease, is defined as the accumulation of intrahepatic fat of at least 5% of liver weight 2. This condition can be caused by an imbalance between the delivery or synthesis of fatty acids in the liver and their disposal through oxidative pathways or secretion into the blood as a component of triacylglycerols in very low density lipoprotein 3.
Characteristics of Hepatic Steatosis
The key characteristics of hepatic steatosis include:
- Accumulation of triacylglycerols within the cytoplasm of hepatocytes to the degree that lipid droplets are visible microscopically 3
- Association with obesity, type 2 diabetes, and dyslipidemia 2
- Increased flux of fatty acids to the liver, increased de novo lipogenesis, and/or reduced clearance through β-oxidation or very-low-density lipoprotein secretion 2
Prevalence of Hepatic Steatosis
Hepatic steatosis is a common condition, with a prevalence of:
- About 35% in the general population 4
- 75% in obese persons 4
- Almost universally present amongst morbidly obese diabetic patients 5
Clinical Implications
Hepatic steatosis can lead to: