Oral amino acid supplementation reduces infection
Oral amino acid supplementation reduces infection

Effects of oral amino acid supplementation on long-term-care-acquired infections in elderly patients

Overview

Due to a high rate of infections in their Geriatric Intensive Rehabilitation Center of approximately 80%, and the increased risk of mortality and morbidity due to these infections, Italian researchers sought nutritional interventions for improving patients’ immune defenses. 

Researchers hypothesized that supplementation with essential amino acids (EAAs) may help to decrease the rate of infections acquired during hospitalization. EAAs such as leucine, glutamine, arginine, glycine, and methionine help regulate cell activity and the immune system. Inadequate intake of EAAs also contributes to muscle wasting in older adults, particularly in circumstances of illness and bed rest. 

Trial Length

1 month

Number of Subjects

80

Gender

All genders

Age Range

71 - 87

The Goal

To determine if supplementing with essential amino acids can help decrease the rate of infections in hospitalized geriatric patients and to analyze the contributing causes of infection.  

The Results

Researchers separated 80 elderly adults hospitalized at their geriatric institute into two groups: one group received 8 grams of essential amino acids a day and the other received a placebo. 

Over the course of a month 67.5%, or 54 out of 80, patients acquired an infection. However, the infection rate in the group receiving EAAs was 30% lower (21 out of 40 patients) than the infection rate in the placebo group (33 out of 40 patients).  

The infection rate in the group receiving EAAs was 30% lower (21 out of 40 patients) than the infection rate in the placebo group (33 out of 40 patients).

Anemia and inflammation as risk factors for infection

An examination of the risk factors for infection showed that anemic patients as well as those with high inflammation markers, including C-reactive protein (CRP), were at increased risk.  

Conclusion

Findings suggest that oral supplementation with EAAs can help lower the risk of long-term-care-acquired infections in elderly patients by as much as 30%. Furthermore CRP and blood hemoglobin levels, a marker of anemia, are risk factors for infection.

The Why?

Elderly patients are prone to infections when hospitalized over long periods. Preventative measures such as oral health and hygiene assistance are not enough to significantly reduce the risk of infections, in part due to the immune-compromised nature of many elderly patients upon admission. 

This high infection rate greatly increases the risk of mortality and medical costs. Nutritional interventions such as supplementing with essential amino acids may go far in helping to reduce the incidence of infection in elderly patients. 

Citation

Aquilani R, Zuccarelli GC, Dioguardi FS, Baiardi P, Frustaglia A, Rutili C, Comi E, Catani M, Iadarola P, Viglio S, Barbieri A, D'Agostino L, Verri M, Pasini E, Boschi F. Effects of oral amino acid supplementation on long-term-care-acquired infections in elderly patients. Arch Gerontol Geriatr. 2011 May-Jun;52(3):e123-8. doi: 10.1016/j.archger.2010.09.005. PMID:20934757