ESPEN Guidelines on Definitions and Terminology of Clinical Nutrition

Nutritional status is defined as the physiological condition of the body resulting from the intake, absorption, and utilization of nutrients, as well as the influence of disease and environmental factors. ESPEN categorizes nutritional status as either normal or abnormal, with malnutrition being the primary abnormal condition.

Malnutrition is a state resulting from lack of intake or uptake of nutrition that leads to altered body composition (decreased fat-free mass) and body cell mass, leading to diminished physical and mental function, and impaired clinical outcome from disease. ESPEN recognizes various types including undernutrition, overnutrition, and specific nutrient deficiencies.

Disease-related malnutrition refers to malnutrition caused by acute or chronic disease states that interfere with nutrient intake, absorption, metabolism, or utilization. It represents the most common form of malnutrition in hospital settings and affects patients across various medical specialties.

Cachexia is a complex metabolic syndrome associated with underlying illness and characterized by loss of muscle with or without loss of fat mass. The prominent clinical feature of cachexia is weight loss in adults (corrected for fluid retention) or growth failure in children (excluding endocrine disorders). Cachexia is often associated with advanced chronic diseases such as cancer, chronic heart failure, and chronic obstructive pulmonary disease.

Sarcopenia is a progressive and generalized skeletal muscle disorder involving the accelerated loss of muscle mass and function. It is associated with increased adverse outcomes including falls, fractures, physical disability, and mortality. sarcopenia may occur independently or as a component of other conditions including cachexia and malnutrition.

Nutritional risk refers to the risk of a patient developing or maintaining malnutrition, or the risk that malnutrition will affect clinical outcome. Nutritional risk screening is the first step in clinical nutrition care, involving simple, validated methods to identify patients who would benefit from comprehensive nutritional assessment and intervention.

Nutritional screening is a rapid, simple process to identify patients who are already malnourished or at risk of becoming malnourished. ESPEN recommends that all hospital patients be screened at admission, with regular follow-up screening throughout their hospital stay. Screening tools should be validated, simple to use, and require minimal training.

Nutritional assessment is a comprehensive approach to define nutritional status using medical, nutritional, and medication histories; physical examination; anthropometric measurements; and laboratory data. Unlike screening, assessment provides a full evaluation of all aspects of nutrition and is conducted by a healthcare professional with specific nutrition expertise.

Nutritional support refers to the provision of nutrients orally, enterally, or parenterally with therapeutic intent. This includes nutritional counseling, oral nutritional supplements, enteral nutrition, and parenteral nutrition. The primary goal of nutritional support is to prevent or correct malnutrition and its associated complications.

Oral nutritional supplements are manufactured liquid or semi-solid products prescribed to supplement the normal diet and provide additional nutrients. ONS are administered orally and contain defined quantities of energy and macro- and micronutrients. They play a crucial role in the management of malnutrition, particularly in community and hospital settings.

Enteral nutrition is nutritional support delivered via the gastrointestinal tract, either orally or through a tube (enteral tube feeding). ESPEN defines enteral nutrition as the preferred route of nutritional support when the gastrointestinal tract is functional and accessible. Various delivery methods include nasogastric, nasojejunal, percutaneous endoscopic gastrostomy (PEG), or jejunostomy tubes.

Parenteral nutrition is the intravenous administration of nutrients, bypassing the gastrointestinal tract. It is indicated when the gastrointestinal tract cannot be used, is non-functional, or when nutritional needs cannot be met via enteral routes. PN may be total (meeting all nutritional requirements) or supplemental (complementary to enteral or oral intake).