This study aimed to analyze demographic and clinical features associated with posterior reversible encephalopathy syndrome-related mortality (PRES-RM) in the United States. 

PRES is characterized by acute or subacute onset of symptoms including but not limited to headache, seizures, encephalopathy, and visual disturbance. The pathophysiology is largely unknown, but some mechanisms propose that it occurs secondary to impairment of cerebrovascular endothelial autoregulation, most commonly in the setting of severely elevated blood pressure. Although PRES is believed to be treatable and reversible, it may be associated with considerable morbidity and mortality. 

Data was extracted from the National Inpatient Sample (NIS) from 2016-2022. To evaluate whether demographic and clinical characteristics were associated with PRES-RM, logistic regression models were estimated. The ICD-10 code I67.83 was used to identify PRES. The data included in this study utilized de-identified administrative claims data, ensuring patient anonymity and confidentiality.

There were an estimated 15,166 hospitalizations for PRES with an in-hospital mortality of 4.8% (n=783). Neurologic conditions that were significantly associated with increased mortality included status epilepticus (OR=1.43, p=0.0131), ischemic stroke (OR=2.25, p<0.0001), cerebral edema (OR=1.80, p<0.0001), infectious/inflammatory encephalitis (OR=1.70, p=0.0236), and spontaneous intracerebral and subarachnoid hemorrhages. Respiratory failure (OR=5.43, p<0.0001) and sepsis (OR=2.45, p<0.0001) were significantly associated with mortality. COVID-19 infection, liver disease, kidney disorders, complications related to transplanted organs, and malignancy also carried higher odds of mortality. Concomitant conditions that were associated with lower mortality included history of primary/essential hypertension (OR=0.80, p=0.0325), epilepsy/seizures (OR=0.67, p<0.0001), and hypertensive crisis (OR=0.63, p<0.0001). Demographic factors associated with higher PRES-RM included age, female sex, insurance type, and hospital type/size.

This study revealed several novel findings regarding in-hospital mortality related to PRES. We highlight important protective and deleterious factors associated with PRES-RM. These findings may aid physicians in the prognostication of these patients.