Longitudinal change of Th1, Th2, and Th17 cells and their relationship between cognitive impairment, stroke recurrence, and mortality among acute ischemic stroke patients

BACKGROUND: T‐helper (Th) cells regulate immunity and inflammation, and modulate cognitive impairment in both cardio‐cerebrovascular and neurological diseases. This study aimed to explore the correlation of longitudinal change of Th1/2/17 cells with cognitive impairment and prognosis in acute ischemic stroke (AIS). METHODS: Th1/2/17 cells were detected by flow cytometry in peripheral blood samples from 150 AIS patients at admission (baseline), Day (D)1, D3, and D7 after admission, and from 30 controls. Mini‐Mental State Examination (MMSE) score among AIS patients at discharge was assessed. Stroke recurrence and mortality were evaluated. RESULTS: Th1 (p = 0.013) and Th17 cells (p < 0.001) but not Th2 cells (p = 0.105) were elevated in AIS patients versus controls. Th1 cells (p = 0.027) and Th17 cells (p < 0.001) but not Th2 cells (p = 0.227) were positively correlated with NIHSS score in AIS patients. Furthermore, Th1 and Th17 cells elevated from baseline to D3 and then decreased on D7 after AIS onset, while Th2 cells illustrated an opposite trend (all p < 0.001). Th17 cells on D1 (p = 0.011), D3 (p = 0.014), and D7 (p < 0.001) were correlated with lower MMSE score, and their levels on D3 (p = 0.033) and D7 (p = 0.004) were related to elevated cognitive impairment. Th1 and Th2 cells were not related to cognitive function (all p > 0.05). Additionally, Th17 cells at baseline, D1, D3, and D7 (all p < 0.05) were increased in recurrent patients versus non‐recurrent patients, and in survived patients versus dead patients, but Th1 or Th2 cells did not vary (all p > 0.05). CONCLUSION: Th17 cells correlate with increased cognitive impairment, stroke recurrence, and mortality among AIS patients.