Long-term mortality of critically ill patients with cancer and delirium who survived to discharge: a retrospective cohort study

PurposeDelirium is common in critically ill patients and has been associated with lower short-term survival; however, its association with long-term survival has been scarcely evaluated and few studies have shown divergent results.MethodsWe conducted a retrospective cohort study of adult patients with cancer admitted to the intensive care unit (ICU) and discharged from hospital from January 2015 to December 2018. We considered delirium present if the Confusion Assessment Method for Intensive Care Unit (CAM-ICU) result was positive. We assessed the association between delirium during ICU stay and long-term mortality (up to three years after discharge). We also assessed the association between delirium type (hypoactive, hyperactive, and mixed) with long-term mortality.ResultsWe included 3,079 patients. Of these, 430 (14%) were considered delirious at some point during their ICU stay. Delirium was associated with one-year mortality after hospital discharge (hazard ratio [HR], 1.58; 95% confidence interval [CI], 1.36 to 1.83) after adjustment for potential confounders, but not with one to three year-mortality (HR, 0.92; 95% CI, 0.61 to 1.39). Hypoactive and mixed delirium were associated with one-year mortality (HR, 1.77; 95% CI, 1.46 to 2.14 and HR, 1.56; 95% CI, 1.21 to 2.00, respectively), but none of the delirium motor types was associated with one to three-year mortality.ConclusionsWe observed that delirium during ICU stay was associated with increased one-year mortality, but was not with mortality after one year. This association was observed in hypoactive and mixed delirium types but not with hyperactive delirium. ObjectifLe delirium est frequent chez la patientele gravement malade et a ete associe a une survie reduite a court terme; son association avec la survie a long terme n'a cependant que tres peu ete evaluee et les rares etudes ont affiche des resultats divergents.MethodeNous avons mene une etude de cohorte retrospective de patient center dot es adultes atteint center dot es de cancer admis center dot es a l'unite de soins intensifs (USI) et ayant recu leur conge de l'hopital entre janvier 2015 et decembre 2018. Nous avons considere qu'un delirium etait present si le resultat de la Methode d'evaluation de la confusion pour l'unite de soins intensifs (CAM-USI) etait positif. Nous avons evalue l'association entre le delirium pendant le sejour aux soins intensifs et la mortalite a long terme (jusqu'a trois ans apres le conge). Nous avons egalement evalue l'association entre le type de delirium (hypoactif, hyperactif et mixte) et la mortalite a long terme.ResultatsNous avons inclus 3079 patient center dot es. De ce nombre, 430 (14 %) personnes ont ete considerees comme en delirium a un moment donne pendant leur sejour a l'USI. Le delirium etait associe a la mortalite a un an apres le conge de l'hopital (rapport de risque [RR], 1,58; intervalle de confiance [IC] a 95%, 1,36 a 1,83) et apres ajustement des donnees pour tenir compte des facteurs de confusion potentiels, mais pas a la mortalite d'un a trois ans apres le conge (RR, 0,92; IC 95%, 0,61 a 1,39). Les deliriums hypoactif et mixte etaient associes a la mortalite a un an (RR, 1,77; IC 95 %, 1,46 a 2,14 et RR, 1,56; IC 95 %, 1,21 a 2,00, respectivement), mais aucun des types moteurs de delirium n'etait associe a la mortalite d'un a trois ans.ConclusionNous avons observe qu'un delirium pendant le sejour a l'USI etait associe a une augmentation de la mortalite a un an, mais pas a la mortalite apres un an. Cette association a ete observee dans les types de delirium hypoactif et mixte, mais pas avec le type hyperactif.