Circulating UCH‐L1 levels are significantly increased after acute neurological insults such as traumatic brain injury, subarachnoid hemorrhage, ischemic stroke, hypoxic‐ischemic encephalopathy, and cardiac arrest,13, 14, 15, 16, 17, 18 and altered UCH‐L1 expression is an indicator of brain injury severity and a predictor of neurological outcomes.17, 19 To the authors’ knowledge, no studies have investigated the utility of serum UCH‐L1 level as a predictor of cognitive impairment after AOPP. Here, UCHL1 is linked to subarachnoid hemorrhage.