We in medicine have long wondered if a period spent in delirium during a hospitalization leads to a change in the trajectory of cognitive decline (a phenomenon any busy clinician would vouch he or she has seen many times) or if that accelerated decline is due to other comorbidities. Whereas many hospital-acquired conditions are considered short-term complications (eg, hospital-acquired pneumonia), we increasingly recognize that the effect of hospitalization on patients' functional and cognitive health may be prolonged or permanent.