Correlation of deglutition in subacute ischemic stroke patients with peripheral blood adaptive immunity: Essential amino acid improvement

Abstract

We aimed to document in stroke patients peripheral blood immune cell profiles, their relations with neuro-functional tests, and any possible influence of supplemented essential amino acids (EAAs) may have on both the immune system and the relationship of the latter with neuro-function.Forty-two dysphagic stroke patients (27 men; 71±9 years) underwent bio-humoral measurements, neuro-functional tests, including Functional Independence Measure (FIM) and Dysphagia Outcome and Severity Scale (DOSS), and were randomized to receive EAAs 8 g/d (EAA group) or isocaloric maltodextrin (placebo group).At discharge all measurements were repeated 38±1 days after randomization.At admission, total white cell (TWC), neutrophil (N), and lymphocyte (Lymph) counts were normal and the N/Lymph ratio was higher than normal values (<3.0). At discharge, both TWC and N decreased while Lymph increased significantly. As a result, the N/Lymph ratio significantly decreased (P <0.001) returning to normal levels. Absolute Lymph counts and Lymph % TWC correlated positively with DOSS (r = +0.235, P = 0.04 and r = +0.224, P = 0.05, respectively), negatively with C-reactive protein natural logarithm (ln CRP) (P = 0.02 and P = 0.0001, respectively), which is an inflammation marker. N correlated positively with ln CRP (P = 0.001) and had a slight negative association with FIM (P = 0.07). The N/Lymph ratio was inversely related to FIM (r = -0.262, P = 0.02) and DOSS (r = -0.279, P = 0.01). Finally, FIM correlated with DOSS (r = +0.35, P = 0.05).For the regression analysis, the overtime changes of Lymph % TWC correlated significantly with DOSS (P = 0.01). There was a positive correlation between Lymph % TWC and DOSS for the entire stroke population (P = 0.015). While this correlation was not important for the placebo group (P = 0.27), it was significant in the EAA subgroup (P = 0.018).In the sub-acute stroke stage, there may be slight alterations of peripheral blood immune cells. Lymph cells are associated with improved neuro-function tests with evidence that this association is enhanced by supplementing EAAs.

Keywords: dysphagia; essential amino acids; immune system; sub-acute stroke.