Neuron-specific enolase and long-term neurological outcome after OHCA - A validation study

Aims: To investigate what NSE levels predict long-term neurological prognosis at 24, 48 and 72 hours after ROSC in a cohort of out-of-hospital cardiac arrest and to validate previously suggested NSE cut-offs, including the latest ERC guidelines (2021). Methods: Patients admitted to intensive care units in four hospitals in Southern Sweden between 2014-2018 were included. Blood samples were handled by a single local laboratory. The primary outcome was neurological outcome according to the Cerebral Performance Category (CPC) scale at 2-6 months after cardiac arrest. Results: 368 patients were included for analysis. A <2% false positive rate for the prediction of poor neurological outcome was achieved with an NSE cut-off value of >101 lg/L at 48 hours and >80 lg/L at 72 hours. The cut-off suggested by the recent ERC guidelines of >60 lg/L at 48 and/or 72 hours generated a false positive rate of 4.3% (95 %CI 0.9-7.4%). Conclusion: A local validation study of the ability of serum levels of neuron-specific enolase to predict long-term poor neurological outcome after out-of-hospital cardiac arrest generated higher cut-offs than suggested by previous publications.