Early onset delirium incidence and risk factors in hematology oncology patients admitted to the intensive care unit: A retrospective cohort study.

BACKGROUND

Delirium occurs frequently in intensive care unit (ICU) patients; however, there are limited data evaluating its impact on critically ill hematology-oncology patients. We aimed to determine the incidence and risk factors for early-onset delirium development in hematology-oncology patients admitted to the ICU.

METHODS

This single-center, retrospective cohort study evaluated the primary outcome of incident delirium within 7 days of ICU admission in adults admitted to the hematology-oncology medical or surgical ICU. Patients with delirium (DEL) were compared to those without (No-DEL) for evaluation of secondary endpoints including hospital mortality, ICU, and hospital length of stay (LOS). Multivariable logistic regression modeling was performed to identify independent risk factors for delirium.

RESULTS

Delirium occurred in 125 (51.2%) of 244 patients. Inhospital mortality was significantly higher in the DEL vs. No-DEL group (32.8% vs. 15.1%, = 0.002). Median (1 and 3 quartiles) ICU and hospital LOS were significantly longer in the delirium group, respectively (6 [4-10] days vs. 3 [2-5] days, < 0.001, and 21 [14-36] days vs. 12 [8-22] days, < 0.001). Higher Sequential Organ Failure Assessment score, high-dose corticosteroids, mechanical ventilation (MV), and brain metastases were each independently, associated with an increased delirium risk.

CONCLUSION

Hematology-oncology patients admitted to the ICU frequently develop delirium. Consistent with literature in nonhematology-oncology critically ill patients, identified independent risk factors for delirium were MV and organ dysfunction. Risk factors unique to the critically ill hematology-oncology patient population include high-dose corticosteroids and brain metastases. Further research is needed to evaluate strategies to mitigate delirium development in this population based on risk assessment.