Abstract: Objective To investigate the changes of peripheral blood T-lymphocyte subsets, serum procalcitonin (PCT) and high-sensitivity-C-reactive protein (hs-CRP) levels in elderly patients with stroke-associated pneumonia (SAP). Method sFifty-nine patients with senile stroke admitted to hospital within 24 hours from February 2017 to February 2018 in our hospital were selected as study subjects. 35 patients with SAP within 1 week were included in group A, and 24 patients without SAP were included in group B in this study; 45 cases of physical examination in our hospital at the same period were used as control group. Peripheral blood T lymphocyte subsets, serum PCT and hs-CRP levels were measured and compared. Results The levels of CD3⁺, CD4⁺, and CD4⁺/CD8⁺ in group A and B were lower than those in control group. The level of CD8⁺ was higher than that in control group (P<0.05). The ratio of CD4⁺/CD8⁺ in group A was lower than that in group B (P<0.05); Serum PCT and hs-CRP levels in group A and B were significantly higher than those in control group (P<0.05); Serum PCT and hs-CRP levels were higher in group A than in group B, the difference was statistically significant (P<0.05). Conclusion sThe elderly patients with SAP have lower levels of cellular immune function at the early onset, and serum PCT and hs-CRP levels are higher. Serum PCT and hs-CRP show significant clinical value for the detection of early stroke-associated pneumonia

Key words: Elderly, SAP, Peripheral blood T lymphocyte subsets, Serum PCT, hs-CRP