Confluence between the intrinsic and extrinsic apoptosis pathways is reached at the point of caspase-3 activation, which induces death cell. Higher serum caspase-3 levels have been recorded on day 1 of traumatic brain injury (TBI) in 30-day non-survivors compared to survivors. The objectives of this study therefore were to determine whether serum caspase-3 levels are persistently higher in non-survivors than in survivors, and whether these levels may be used to predict 30-day mortality.A prospective observational study was carried out.Six Spanish Intensive Care Units.Patients with severe isolated TBI (defined as Glasgow Coma Scale9 points and non-cranial Injury Severity Score10 points).Serum caspase-3 concentrations were measured on days 1, 4 and 8 of TBI.Thirty-day mortality was considered as the study endpoint.In comparison with non-survivors (n=34), 30-day survivors (n=90) showed lower serum caspase-3 levels on days 1 (p=0.001), 4 (p0.001) and 8 (p0.001) of TBI. Analysis of the ROC curves showed serum caspase-3 concentrations on days 1, 4 and 8 of TBI to have an AUC (95% CI) in predicting 30-day mortality of 0.70 (0.61-0.78; p=0.001), 0.83 (0.74-0.89; p0.001) and 0.87 (0.79-0.93; p0.001), respectively.The novel findings of our study were that serum caspase-3 levels during the first week of TBI were lower in survivors and could predict 30-day mortality.
