CYP2C19 loss-of-function alleles and early neurological deterioration in minor ischemic stroke receiving dual antiplatelet therapy

Objective Early neurological deterioration (END) is a common complication after acute ischemic stroke (AIS). Dual antiplatelet therapy (DAPT) with aspirin and clopidogrel is widely used in selected patients with minor ischemic stroke (MIS) to reduce early recurrent ischemic events. This study aimed to investigate the incidence of END in patients with MIS receiving DAPT and explore factors associated with END.Methods We performed a single-center retrospective cohort study including consecutive cases of MIS treated with DAPT. END was defined as an increase of ≥2 points in the NIHSS score from baseline within 24 h of admission. Demographic information, vascular risk factors, imaging findings, and relevant laboratory parameters were systematically reviewed.Results A total of 118 patients were enrolled in the study, and 16 patients (13.6%) developed END. CYP2C19 loss-of-function (LOF) allele carriers (OR 11.05, p < 0.001) and patients with diabetes mellitus (OR 4.08, p = 0.024) were at increased risk of END, and END was associated with substantially poorer functional outcomes at 90 days (mRS 0–2 75% vs. 95.1%, p = 0.019).Conclusion END is common among patients with MIS and is associated with poorer 90-day functional outcomes. CYP2C19 LOF carrier status may be associated with an increased risk of END among patients with MIS receiving aspirin plus clopidogrel DAPT.