leading, quite possibly, to a decrease in the up to now level occurrence rate of chronic illness nationwide that I pointed out above.
Of course, I realize that many of you at this point in this monograph may be thinking that what I am hypothesizing is little more than an unrealistic “pipedream” that wildly oversimplifies a complex scenario. Surely loss of muscle mass and its restoration can’t be that important to the resolution of chief complaints!! Therefore, to assist me in my effort to convince you, I am going employ a recently written paper by one of the world’s leading authorities in the use of protein and amino acid supplements in the clinical setting, Robert R. Wolfe, PhD. His most recent paper entitled “The 2017 Sir David P Cuthbertson lecture, Amino acids and muscle protein metabolism in critical care” (Wolfe RR. Clin Nutr, published online ahead of print, December 21, 2017), for me, makes it clear that, for sick people, loss of protein, particularly in the form of muscle mass, is a major issue impeding successful recovery.
Before proceeding with my review and commentary of this paper, I would like to offer a clarification. As you may have noticed, the title of the paper suggests that it only applies to critically ill patients, not chronically ill patients. Interestingly, a large body of research makes it clear that the basic mechanisms leading to loss of protein and muscle mass are the same in both critically and chronically ill individuals, with the only difference being a matter of degree. In turn, the success with protein/ amino acid supplementation pointed out by Wolfe in critically ill patients from another paper I will discuss can be successfully extrapolated to chronically ill patients. Therefore, I feel very confident that application of what Wolfe is recommending for critically ill patients will lead to success with those many chronically ill patients who have both low dietary and supplemental protein intake.
The first quote from the Wolfe paper I would like to feature points out the futility of the high carbohydrate diet whether given therapeutically as noted by Wolfe or employed by patient personal choice in the outpatient, chronic illness situation: “…adverse effects of excessive caloric intake, particularly in the form of glucose became evident. For example, we found that glucose given at rates in excess of caloric requirement stimulated fat synthesis in the liver…”
Therefore, as I mentioned, the theme of this paper is that, with sick individuals, it is generally advisable to increase intake of protein/amino acids.
What is it, specifically, from a metabolic standpoint that makes increased dietary protein and amino acids so important to recovery? This question can be answered by the following two quotes. First: “Studies have confirmed that an increase in resting energy expenditure occurs in almost all form of critical illness and injury.”
Thus, during sickness, the body will tend to metabolize more lean body mass to meet this need for increased energy. In turn:
THE ORIGINAL INTERNIST MARCH 2018
“The primary focus of nutritional support should be the net loss of body protein.”
Are your chronically ill patients experiencing net loss of body protein? As many of you have probably seen in your practices, simple grip strength and bioelectric impedance measurements will prove that the answer is “yes” in many if not most of these individuals.
In the healthy individual protein synthesis is higher than the rate of protein breakdown right after a healthy meal. However, between meals, during the “post-absorptive state,” the reverse is true: “The rate of protein breakdown exceeds the rate of protein synthesis at the whole body level in the post-absorptive state in all circumstances, including in normal subjects. Protein breakdown will always exceed the rate of protein synthesis in the post-absorptive state because the essential amino acids (EAAs) that are required for protein synthesis cannot be produced in the body. In the post-absorptive state the only source of EAAs is protein breakdown, and some of the EAAs released from protein breakdown are oxidized and thus not available as precursors for protein synthesis. The obligatory oxidation of some of the EAAs released from protein breakdown explains the negative protein balance in the controls values of 36 normal men and women…”
Therefore, as noted by this quote, between meals, no matter how healthy the individual or high quality the meal, there will always loss of body protein between meals because some of the amino acids need to be oxidized to provide energy to maintain optimal between meal functioning. However, as I mentioned, in the healthy situation this loss of body protein will be more than offset by the next meal. However, what about the sick person mentioned above who has increased energy expenditure and increased breakdown of body protein, a condition that Wolfe describes as a “catabolic state”: “Regardless of the catabolic state, there is a significant acceleration of whole body protein breakdown relative to the rate of synthesis in the post-absorptive state. On average, the net loss of body protein is approximately doubled in the catabolic state. The clinical management of catabolic patients must therefore place a high priority on maintaining the body protein pool with adequate nutritional and metabolic support to balance the potential adverse effects of a rapid loss of lean body mass.”
Are your chronically ill patients experiencing the doub- ling of the normal rate of protein breakdown noted by Wolfe above? Probably not. Nevertheless, research on chronically ill patients, particularly those who are middle- aged or older, suggests their catabolic rate of protein loss is still significant.
What is the impact of loss of body protein on chances for recovery? As I have suggested: “The net loss of body protein can be so extensive in catabolic states that both acute as well as long-term recovery is adversely affected.”
What might be the best solution to loss of body protein? Wolfe states:
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