Delirium Common in Advanced Cancer Patients Visiting ER

July 27, 2016

Ten percent of advanced cancer patients have developed delirium, but it is often missed by emergency department physicians.

About 10% of patients with advanced cancer presenting to the emergency department were found to have delirium, according to the results of a single-center study published in Cancer.

“Delirium was frequently missed by emergency department physicians despite prior education on delirium,” wrote researchers led by Ahmed F. Elsayem, MD, MPH, of the University of Texas MD Anderson Cancer Center. “This finding highlights the need for systematic screening for delirium in advanced cancer patients visiting the emergency department.”

According to the study, delirium is a common symptom in patients with advanced cancer, and is associated with significant morbidity and mortality. In addition, a majority of patients with terminal cancer will develop delirium in the last days prior to death.

In this study, Elsayem and colleagues wanted to calculate the prevalence of delirium among patients with advanced disease who presented to the emergency department at MD Anderson Cancer Center. They took a random sample of patients with advanced cancer and assessed them using the Confusion Assessment Method (CAM) to screen for delirium and the Memorial Delirium Assessment Scale (MDAS) to measure its severity. In addition, the emergency department physicians were asked if patients were delirious.

The researchers screened 1,832 patients and 624 met study criteria; 243 patients gave consent and 241 were assessed for delirium.

Using the CAM, 9.1% of the patients were estimated to have delirium (95% CI, 5.47%–12.71%). However, the physicians indicated that 6.4% of patients had delirium, failing to identify delirium in 9 patients.

In a previous study, emergency department physicians accurately identified delirium in only 23% of patients. The researchers noted that the higher identification rate “may be related to our study design, according to which emergency department physicians were educated about delirium before the study and were approached by the research associate for approval before patient enrollment and after patient assessment.”

According to the researchers, 41% of the patients with delirium were still missed by emergency department physicians. “This makes our findings of missed delirium and a lack of discontinuation of contributing drugs more robust because the actual frequency of these findings may even be higher among emergency department physicians who do not undergo such educational intervention,” they wrote.

Delirium was identified in 10% of patients aged 65 or older and 8% of patients aged younger than 65.

Severity screening showed mild delirium in 82% of the patients and moderate delirium in 18%. Patients with delirium had a poorer performance status than patients without delirium (P < .001), but did not differ in any other characteristics examined.

In an editorial that accompanied the article, Peter G. Lawlor, MB, MMedSc, of the palliative care unit at Bruyère Continuing Care in Ottawa, Canada, noted that the rate of 9% seemed low.

“Of the study-eligible patients (n = 624), 47% (n = 291) were noted to be unapproachable for a variety of reasons, including the fact that they were ‘sleeping/tired,’” Lawlor wrote. He noted that some of these patients may have been delirious. Furthermore, selection biases could have occurred as a result of the exclusion of dementia patients and the restricted 10 am to 6 pm interval of participant recruitment. “The generalizability of the study’s prevalence finding is, therefore, limited because of these selection biases,” he concluded.