Alcohol-Related Liver Disease

Definition

Alcohol-Related Liver Disease (ARLD) is a spectrum of liver disorders caused by chronic alcohol consumption, ranging from steatosis (fatty liver) to alcoholic hepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma.

Epidemiology

• Prevalence varies worldwide; high in regions with high alcohol consumption
• More common in men than women, but women are more susceptible to alcohol-induced liver injury at lower doses
• Peak incidence: 40–60 years
• ARLD is a major cause of cirrhosis and liver-related mortality globally
• Genetic predisposition (PNPLA3 gene) and comorbidities like obesity increase risk
• Contributes significantly to liver transplantation needs

Etiology

• Chronic excessive alcohol intake (typically >40–60 g/day for men, >20–40 g/day for women for >5–10 years)
• Pattern of drinking: binge vs continuous heavy drinking
• Coexisting liver disease (HCV, HBV, NAFLD) exacerbates progression
• Nutritional deficiencies (protein-calorie malnutrition, vitamin deficiencies)
• Genetic factors: PNPLA3, TM6SF2, HSD17B13 variants

Pathophysiology

• Alcohol metabolism in liver generates acetaldehyde → hepatocyte injury, oxidative stress, inflammation
• Alcohol induces fat accumulation in hepatocytes (steatosis)
• Chronic inflammation leads to fibrosis via activation of hepatic stellate cells
• Progressive fibrosis results in cirrhosis and portal hypertension
• Kupffer cell activation promotes cytokine-mediated liver injury
• Impaired immune response increases susceptibility to infections