The association between serum orexin A and short-term neurological improvement in patients with mild to moderate acute ischemic stroke

Background: The serum orexin A level was significantly lower among patients with acute ischemic stroke (AIS) and negatively related to the volume of the infarction, but the relationship between serum orexin A and prognosis of AIS was still unclear. We aimed to clarify the association between serum orexin A and the short-term neurological improvement in patients with mild to moderate AIS.

Methods: We consecutively enrolled patients with first ever mild to moderate AIS admitted to hospital within 48 h from symptom onset in this prospective observational study. The serum orexin A concentrations were determined on the second morning since the admission. The short-term neurological improvement was defined as more than 1 point decrease in the National Institute of Health Stroke Scale score within 7 days after admission.

Results: We detected increased serum orexin A level in mild to moderate AIS patients with early onset of stroke-related insomnia (33.44 vs 18.66 pg/ml, p = .004) as well as in patients with short-term neurological improvement compared to those without improvement (31.78 vs 16.24 pg/ml, p = .038). The serum orexin A level was positively associated with the short-term neurological improvement after adjusting for sleep condition and other related variables.

Conclusion: Serum orexin A might be a useful biomarker for the assessment of early prognosis in patients with mild to moderate AIS.