Family identification of delirium in the emergency department in patients with and without dementia : validity of the family confusion assessment method (FAM-CAM)

Abstract

OBJECTIVE To examine the ability of the family-rated Family Confusion Assessment Method (FAM-CAM) to identify delirium in the emergency department (ED) among patients with and without dementia, as compared to the reference-standard Confusion Assessment Method (CAM).

DESIGN Validation study.

SETTING Urban academic ED.

PARTICIPANTS Dyads of ED patients, aged 70 years and older, and their family caregivers (N = 108 dyads).

MEASUREMENTS A trained reference standard interviewer performed a cognitive screen, delirium symptom assessment, and scored the CAM. The caregiver self-administered the FAM-CAM. Dementia was assessed using the Informant Questionnaire on Cognitive Decline in the Elderly and the medical record. For concurrent validity, performance of the FAM-CAM was compared to the CAM. For predictive validity, clinical outcomes (ED visits, hospitalization, and mortality) over 6 months were compared in FAM-CAM positive and negative patients, controlling for age, sex, comorbidity, and cognitive status.

RESULTS Among the 108 patients, 30 (28%) were CAM positive for delirium and 58 (54%) presented with dementia. The FAM-CAM had a specificity of 83% and a negative predictive value of 83%. Most false negatives (n = 9 of 13, 69%) were due to caregivers not identifying the inattention criteria for delirium on the FAM-CAM. In patients with dementia, sensitivity was higher than in patients without (61% vs 43%). In adjusted models, a hospitalization in the following 6 months was more than three times as likely in FAM-CAM positive compared to negative patients (odds ratio = 3.4; 95% confidence interval = 1.2-9.3).

CONCLUSIONS Among patients with and without dementia, the FAM-CAM shows qualities that are important in the ED setting for identification of delirium. Using the FAM-CAM as part of a systematic screening strategy for the ED, in which familiesʼ assessments could supplement healthcare professionalsʼ assessments, is promising.