Changes associated with normal aging increase nutritional risk for older adults. Aging is characterized by diminished organ system reserves, weakened homeostatic controls, and increased heterogeneity among individuals, influenced by genetic and environmental factors.
Nutritional needs of the older individual are determined by multiple factors, including specific health problems and related organ system compromise; an individual's level of activity, energy expenditure, and caloric requirements; the ability to access, prepare, ingest, and digest food; and personal food preferences.
This topic will discuss assessment of nutrition in the older adult, as well as the etiology, evaluation, and treatment of weight loss, overnutrition, and specific common nutrient deficiencies. Related issues of geriatric health maintenance and nutritional assessment are discussed separately. (See "Geriatric health maintenance" and "Approach to the patient with weight loss" and "Dietary and nutritional assessment in adults" and "Vitamin supplementation in disease prevention".)
SCREENING FOR NUTRITIONAL STATUS
Data from studies of acute hospitalization in older patients suggest that up to 71 percent are at nutritional risk or are malnourished . Malnutrition is associated with increased mortality risk . The following criteria for the diagnosis of malnutrition have been recommended in a consensus statement from the Academy of Nutrition and Dietetics (Academy) and the American Society for Parenteral and Enteral Nutrition (ASPEN) :
Two or more of the following six characteristics: