Is Posthospital Syndrome a Result of Hospitalization-Induced Allostatic Overload?

After discharge from the hospital, patients face a transient period of generalized susceptibility to disease as well as an elevated risk for adverse events, including hospital readmission and death. The term posthospital syndrome (PHS) has been used to describe this time of enhanced vulnerability. Based on data from bench to bedside, this narrative review examines the hypothesis that hospitalrelated allostatic overload is a plausible etiology of PHS. Resulting from extended exposure to stress, allostatic overload is a maladaptive state driven by overuse and dysregulation of the hypothalamic-pituitary-adrenal axis and the autonomic nervous system that ultimately generates pathophysiologic consequences to multiple organ systems. Markers of allostatic overload, including elevated levels of cortisol, catecholamines, and inflammatory markers, have been associated with adverse outcomes after hospital discharge. Based on the evidence, we suggest a possible mechanism for postdischarge vulnerability, encourage critical contemplation of traditional hospital environments, and suggest interventions that might improve outcomes.