Long-Term Care Concerns - A Primer on Protein, Part 2
Today’s Dietitian
By Becky Dorner, RD, LD
Vol. 6 No. 5 p. 45

Amidst all the Atkins diet hype, it’s hard for most of us to imagine going without protein in our diets for long periods of time. For healthy adults eating a varied diet, the amount and type of protein may not be a concern. But for older adults with debilitating illnesses, the amount and type of protein and other nutrients provided may impact health outcomes. Determining the best source of protein for a malnourished older adult may depend on the situation and the individual’s ability to consume and utilize the foods he or she eats.

Protein Malnutrition
Our bodies utilize proteins efficiently only if we eat enough carbohydrate and fat to meet individual energy needs. Proteins supply 4 calories per gram and can easily be used for energy if there are not enough other energy sources available.

If a person goes for more than a few weeks without adequate protein, the body will do its best to conserve the amino acids it needs. Eventually though, the body will break down protein faster than it can make it to produce the energy it needs. Health can decline as essential bodily functions slow down because amino acids are not available to produce the proteins needed for vital roles.

Severe food restriction, inadequate intake of calories and protein, or malabsorption may result in protein-energy malnutrition (PEM). Over time, catabolism of skeletal muscle protein occurs. This releases additional amino acids, which are converted to glucose for energy or used for synthesis of needed proteins.

Nitrogen and Nitrogen Balance
Carbohydrates, proteins, and fats all contain carbon, hydrogen, and oxygen. But it is the nitrogen atoms that make proteins unique from carbohydrates and fats.

Healthy people who consume adequate amounts of protein to meet needs are in a state of nitrogen equilibrium: The amount of nitrogen consumed is exactly balanced by the body to what is needed, and the rest is excreted to create this balance. New proteins are needed on a daily basis to maintain this equilibrium.

People who are in a state of severe stress, such as infection, injury, fever, or burns, are in a state of negative nitrogen balance because their bodies excrete more nitrogen than is consumed. Cells must have energy to survive, and if needed, proteins are sacrificed for energy to meet the cells’ needs. If this continues for an extended period of time, muscle wasting and fat loss occurs. Thus, adequate carbohydrate and fat for calories may spare protein to perform their unique bodily functions.

People who are recovering from stress, illness, or a protein deficiency are in a state of positive nitrogen balance because their intake exceeds output.

Protein Needs During Stress
During acute illness or trauma (eg, injury, burns, wounds, major surgery, infection), the body reacts to protect itself with an inflammatory response that increases the demand for additional energy and protein. This results in metabolic alterations that begin at the time of the injury or acute illness and continue until recovery is complete.

Metabolic stress causes poor utilization of carbohydrate, protein, and fat and catabolism of lean body mass protein. Production of energy becomes increasingly dependent on proteins.

This series of events can result in an acute PEM in which albumin, transferrin, prealbumin, and retinol-binding protein levels decrease. C-reactive protein (CRP) may increase during the inflammatory response. A negative nitrogen balance occurs due to rapid loss of lean body mass, and muscle wasting is the ultimate result.

Laboratory Assessment of Protein Status
The concern with protein status measurements (such as serum albumin levels) is the difficulty of measuring the inflammatory response. CRP is one indicator that may be useful: It increases in the first four to six hours after trauma or surgery. When the CRP levels begin to subside, this indicates that the body is beginning the anabolic cycle and nutrition intervention is now beneficial. Prealbumin levels begin to rise at about the same time that CRP levels begin to decrease, so prealbumin can also be a good signal as to when to become aggressive with nutrition therapy.

Nutrition Interventions
Older adults in a stressed state need additional calories to be able to utilize protein. If adequate calories are available, then a variety and balance of proteins must be provided for the body to be able to custom make the proteins needed to maintain health and repair damage. This can be achieved in many ways depending on the resident’s ability to consume food and fluid by mouth.

Foods can be fortified to enhance calories and protein, and supplements may be used as accepted and tolerated by residents. For some residents, volume is an issue, and fortified foods and/or concentrated supplements are needed for a positive response to interventions. In some cases, enteral or parenteral feedings must be used to achieve the nutritional needs of stressed residents. Armed with the right information and knowledge, you can make informed decisions for appropriate nutrition interventions.

— Becky Dorner, RD, LD, is a speaker and author who provides publications, presentations, and consulting services to enhance the quality of care for our nation’s older adults. Visit www.beckydorner.com for free articles, newsletters, and information, or call 800-342-0285.

References for this article are available upon request by e-mailing TDeditor@gvpub.com.

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