Elevated RDW indicates a severe imbalance in red blood cell regulation, involving both defective erythropoiesis and unusual red blood cell longevity, possibly linked to several metabolic disorders, such as shortened lifespan of telomere length, oxidative stress, inflammation, poor nutritional status, dyslipidemia, hypertension, erythrocyte fragmentation, and alteration of erythropoietin function, both of which are implicated in the pathophysiology of delirium. This evidence concerns the gene EPO and hypertensive disorder.