A 24 h Delay in the Redox Response Distinguishes the most Severe Stroke Patients from Less Severe Stroke Patients

Objective: Admission measures of stroke severity are often used to assess 30-90 day outcomes. Since some patients have a poor outcome by discharge, we sought to identify a biomarker that distinguishes severities as well as acute outcomes. Disruptions in the equilibrium of the redox system were used as an indicator of stroke severity and acute outcome. Methods: Oxidation reduction potential (ORP), a measure of the redox system, was assessed in plasma at admission and 24 h later in patients admitted with stroke symptoms (n=76). Overall differences in ORP between stroke patients and healthy controls were determined. Within stroke patients, changes in ORP as a function of hospital discharge status, modified Rankin scale and NIHSS were assessed using ANOVA and the ability to predict acute outcome in ischemic stroke patients based on ORP was compared to NIHSS using Receiver Operator Characteristics. Results: Stroke patients had higher ORP levels than healthy controls (p 146.6 mV at admission was associated with a 46 fold increased odds of a good acute outcome. Conclusion: ORP measured at admission identified patients which died or were discharged to hospice based on their lower ORP values. The lower ORP and subsequent increase 24 h later in the most severely affected patients may reflect a failure or a delay in engaging the redox system, a response that may, during acute stages, be beneficial.