In 2018, the Brain Trauma Indicator, an assay measuring GFAP together with ubiquitin terminal-hydrolase-L1 in blood received Food and Drug Administration approval for assessing traumatic brain injury severity aiding the decision-making for CT scan use.141 With technical advances and the advent of fourth-generation immunoassays over the past decade, increasing evidence supports the diagnostic utility of plasma GFAP in distinguishing Alzheimer’s disease from other dementias. Here, GFAP is linked to brain injury.