HMOX1 and delirium: Nevertheless, some human studies of the role of HO‐1 in TBI diseases indicate transferability of preclinical data: a publication showed HO‐1‐positive microglia at the side of damage in human TBI (Beschorner et al. 2000), another study on severe TBI in infants displayed significant HO‐1 expression in the cerebrospinal fluid (Cousar et al. 2006), as well as our own previous work analysing patients with delirium, where HO‐1 expression measurement helped predict delirium occurrence post‐TBI (Steimer et al. 2021).