[Causes of protein-calorie malnutrition].

In developed countries, medical conditions, rather than lack of food, are the main contributors to malnutrition. Undernutrition is especially common in older persons, occurring in 5-12% of community-dwelling older persons, in 30-61% of hospitalized older persons, and in 40-85% of persons in long-term care institutions. The multi-factorial nature of undernutrition in the elderly forces a structured differential diagnostic approach to determine underlying causes. Heightened physician awareness of nutritional problems and prompt risk assessment is imperative to prevent the sequelae of undernutrition. This structured approach to the differential diagnosis is essential to evaluate potentially reversible causes of malnutrition.