Usefulness of neuron specific enolase in prognostication after cardiac arrest: Impact of age and time to ROSC

Aim of the study: We evaluated the impact of patient age and time from collapse to return of spontaneous circulation (ROSC) on the prognostic accuracy of neuron specific enolase (NSE) after out-of-hospital cardiac arrest (OHCA). Methods: Using electrochemiluminescence immunoassay, we measured serum concentrations of NSE in 249 patients who were admitted to intensive care units after resuscitation from OHCA. In each quartile according to age and time to ROSC, we evaluated the ability of NSE at 48 h after OHCA to predict poor outcome (Cerebral Performance Category 3-5) at 12 months. Results: The outcome at 12 months was poor in 121 (49%) patients. The prognostic performance of NSE was excellent (area under the receiver operating characteristic curve, AUROC, 0.91 [95% confidence interval, 0.81-1.00]) in the youngest quartile (18-56 years), but worsened with increasing age, and was poor (AUROC 0.53 [0.37-0.70]) in the oldest quartile (72 years or more). The prognostic performance of NSE was worthless (AUROC 0.45 [0.30-0.61]) in the quartile with the shortest time to ROSC (1-13 min), but improved with increasing time to ROSC, and was good (AUROC 0.84 [0.74-0.95]) in the quartile with the longest time to ROSC (29 min or over). Conclusion: NSE at 48 h after OHCA is a useful predictor of 12-month-prognosis in young patients and in patients with a long time from collapse to ROSC, but not in old patients or patients with a short time to ROSC.