Essential amino acid supplementation is associated with reduced serum C-reactive protein levels and improved circulating lymphocytes in post-acute inflamed elderly patients

Background Persistent systemic inflammation leads to multidistrectual body dysfunctions. Attenuation of inflammation may improve patients' functional and life prognoses. We hypothesized that essential amino acids (EAAs) given to elderly patients in rehabilitation after acute diseases may be associated with a reduced inflammatory state. Therefore, this retrospective study investigated whether the supplementation of EAAs - modulators of immune competence - was associated with a reduced inflammation rate in elderly patients. Methods The medical records of 282 patients admitted to the rehabilitation (rehab) institute after acute index events (surgery or medical diseases) (age: 81.18 +/- 8.58 years; females: 67.9%) were analyzed. Results 46 patients (16.3% of the entire population) had received EAA supplements (S), whereas the remaining 236 patients had not (N-S). Systemic inflammation (I) (serum C-reactive protein (CRP) > 0.5 mg/dL) was present in 67.4% of the I-S group and 57.2% of the I-N-S group. During rehab, the I-S group (but not the I-N-S group) showed a reduction in CRP levels (p = 0.03) and an increase in circulating lymphocytes (p = 0.035), immune cells of the adaptive immune system. C-reactive protein levels remained virtually unchanged in non-inflamed patients who received supplements but increased in non-inflamed patients who did not receive supplements (p = 0.05). Stratified for developed infections, CRP levels reduced in S patients (p = 0.008) but did not in N-S patients. Conclusion EAA supplementation was associated with reduced inflammation in both inflamed and infected patients. In addition, EAA supplementation was associated with increased circulating lymphocytes in inflamed patients.