Defining Malnutrition and Its Effects

Malnutrition is a deficiency, excess, or imbalance of caloric energy of one or more nutrients, including protein, vitamins, minerals, or trace elements. In the hospital setting, the most severe malnutrition problems are associated with Protein Calorie Malnutrition (PCM), also known as Protein Energy Malnutrition (PEM), which occurs in both chronic and acute forms. Proteins and their constituent amino acids have little or no nonfunctional storage, so malnutrition typically first causes a decrease or imbalance in the patient's proteins. Because proteins "do the work" in the body, PCM directly impairs the function of affected organs; it also has a generalized impact on the immune system, in which proper function depends on protein interactions.

The generalized impact of malnutrition leads to multiple effects. In numerous studies (see Recommended Readings), malnutrition has been found to be the dominant or the only variable associated with poor healing, higher rate of complications, and higher rates of morbidity and mortality. Malnutrition-induced suppression of the immune system can cause:

• Progressive weight loss
• Weakness
• Infections
• Poor wound healing