Introduction: Delirium has been well studied among patients in the intensive care unit (ICU); however, data beyond the ICU is limited. The purpose of this study is to prospectively evaluate the incidence and associated risk factors for delirium in noncritical care areas (NCCA).
Methods: After institutional review board approval, a prospective cohort study was conducted at our urban Level I Trauma Center from December 2015 to February 2016. All patients admitted to the designated study area by a trauma surgeon were included. The Confusion Assessment Method (CAM) was administered every 12 hours until discharge. Delirious patients (CAM+) were administered the CAM-S to quantify the severity of delirium. Demographics, laboratory data, and inpatient medication lists were analyzed.
Results: Of 148 participants, 12 (8%) were CAM+ and 136 (92%) were CAM-. The average CAM-S of CAM+ patients was 7 ± 3. Included patients were aged 52 ± 20 years and 45% were men. Of patients 65 years or older, 9 (21%) were CAM+. Medications associated with delirium were: albuterol (p = 0.01), atorvastatin (p = 0.01), duloxetine (p = 0.04), sertraline (p = 0.04), folic acid (p = 0.01), thiamine (p = 0.01), vitamin D (p < 0.001), haloperidol (p = 0.04), metoprolol (p = 0.02), and vancomycin (p = 0.02). Abnormal laboratory values associated with delirium included: Albumin (p = 0.03; odds ratio [OR], 7.94, 95% confidence interval [CI], 1.1-63.20), Calcium (p = 0.01; OR, 4.95; 95% CI, 1.5-16.7), Sodium (p = 0.04; OR, 3.91; 95% CI, 1.13-13.5), hematocrit (p = 0.04), and mean corpuscular hemoglobin concentration (p < 0.05; OR, 5.29; 95% CI, 1.19-23.46).
Conclusions: Our study demonstrated an 8% incidence of delirium overall in NCCA, increasing to 21% in patients 65 years or older. Many risk factors identified among NCCA patients are consistent with the ICU literature; however, our CAM+ patients had additional risk factors which have not been previously associated with the development of delirium. Screening of NCCA patients for delirium should be considered.
Level of evidence: Prognostic and Epidemological, level IV.