nonalcoholic fatty liver disease
ABBR: NAFLD Fatty infiltration of the liver in patients who are not infected with hepatitis C virus, are not alcoholic, are not taking medications that make fat accumulate in the liver, and are not genetically predisposed to fatty infiltration of the liver.
NAFLD affects roughly 20% of the adult population, with significant geographical, ethnic, and national variation, e.g., with Hispanics having higher rates of NAFLD than Asians.
Obesity, metabolic syndrome, type 2 diabetes mellitus (DM), hypothyroidism, sleep apnea, and polycystic ovaries all are associated with NAFLD.
SYMPTOMS AND SIGNS
Most patients are asymptomatic and unaware of their condition.
Abnormal liver function tests, such as elevated levels of aspartate aminotransferase or alanine aminotransferase in the blood, often prompt an evaluation for hepatitis. If viral hepatitis and other forms of liver disease can be excluded with testing, the appearance of a fatty liver on ultrasound, or a liver biopsy showing fatty infiltration of the liver is used to diagnose NAFLD. A liver biopsy reveals NAFLD when more than 5% of hepatocytes contain fatty deposits.
Weight loss of about 10% of body weight improves NAFLD.
Along with lifestyle modifications (prudent diet, exercise, weight loss, and limitations on alcohol intake) interventions that favorably affect NAFLD include vitamin E supplementation, bariatric surgery, and, in patients with type 2 DM, the oral drug pioglitazone.
IMPACT ON HEALTH
Unmanaged NAFLD can progress to cirrhosis; progression of the disease is relatively slow, typically over decades rather than years.
Consultations with nutritionists, physical therapists, and gastroenterologists can motivate patients to lose weight and avoid adverse consequences of NAFLD.