Interleukin-33 (IL-33), a newly recognized
IL-1 family member, is expressed in various tissues and cells, and involved in pathogenesis of many human diseases. For example,
IL-33 plays a protective role in
cardiovascular diseases. However, the role of
IL-33 in
acute ischemic stroke (AIS) remains unclear. This study aims to investigate whether
IL-33 level in AIS patient serum can be used as a potential diagnostic and prognostic marker. The study included two hundred and six patients with first-ever
ischemic stroke, who were admitted within 72 hours after
stroke onset. The serum level of
IL-33 was measured with ELISA and the severity of AIS patients on admission was evaluated based on the National Institutes of Health
Stroke Scale (NIHSS) score. The functional outcome at 3 months was determined using the Barthel index (BI). We found that serum
IL-33 was significantly higher (P < 0.001) in patients with AIS [57.68 ng/L (IQR, 44.95-76.73)] compared with healthy controls [47.48 ng/L (IQR, 38.67-53.78)].
IL-33 was an independent diagnostic
biomarker for AIS with an OR of 1.051 (95%Cl, 1.018-1.085; P=0.002). Serum
IL-33 was higher (P < 0.05) in the
stroke patients with small
cerebral infarction volume compared to AIS patients with large
cerebral infarction. In addition, serum
IL-33 was also significantly higher (P = 0.001) in the patients with mild
stroke, compared to the patients with severe
stroke. Furthermore, serum
IL-33 level in AIS patients with a worse outcome was higher (P < 0.001) compared to AIS patients with a better outcome.
IL-33 was also an independent predictor for the functional outcome with an adjusted OR of 0.932 (95% CI, 0.882-0.986). Our results suggest that the lower level of serum
IL-33 is associated with large
infarction volume and greater
stroke severity in AIS patients. Thus,
IL-33 can be used as a novel and independent diagnostic and predicting prognostic marker in AIS.