Risk factors for delirium in patients undergoing hematopoietic stem cell transplantation

Delirium is common after hematopoietic stem cell transplantation (HSCT) and is associated with increased morbidity and mortality. Early recognition and treatment have been shown to improve long-term outcomes. We sought to investigate the relationship between potential risk factors and the development of delirium following HSCT.

Fifty-four inpatients admitted for HSCT were assessed prospectively for delirium every 2 to 3 days during their inpatient stay using standardized delirium and neuropsychological measures. Self reports of medical history, medical records, and neurocognitive and psychiatric assessments were used to identify risk factors. Both pre- and post-HSCT risk factors were examined.

Delirium incidence was 35% and occurred with highest frequency in the 2 weeks following transplant. The only pre-transplantation risk factor was lower oxygen saturation (P = .003). Post-transplantation risk factors for delirium included higher creatinine (P < .0001), higher blood urea nitrogen levels (P = .005), lower creatinine clearance (P = .0006), lower oxygen saturation (P = .001), lower hemoglobin (P = .04), and lower albumin (P = .03). There was no observed association with level of cognitive performance, transplant type, disease severity, medical comorbidity index, age, or conditioning regimen.

Routine laboratory values can assist in the identification of high-risk patients before delirium onset to improve early detection and treatment of delirium after HSCT.