Nutrition and alcoholic liver disease.

Malnutrition is a common finding in chronic alcoholics, and protein calorie malnutrition (PCM) is universal and predictive of survival in patients with established alcoholic liver disease (ALD). These patients also demonstrate frequent deficiencies of folate, thiamine, pyridoxine, and vitamin A, which enhance the likelihood of anemia, altered cognitive states, and night blindness. The etiologies of malnutrition in ALD patients are multiple and interactive and include anorexia with inadequate dietary intake, abnormal digestion of macronutrients and absorption of several micronutrients, increased skeletal and visceral protein catabolism, and abnormal interactions of ethanol and lipid metabolism. Numerous, and mostly inadequately controlled, studies have evaluated the potential efficacies of oral, enteral, and parenteral nutrition approaches to treatment of ALD, with mixed results on liver function, clinical improvements, and short- or long-term survival. Targeted metabolic treatments include supplementation with S-adenosylmethionine (SAM) or phosphatidylcholine derivatives, each with promising experimental bases but inconclusive clinical trials.