Hypoactive delirium: assessing the extent of the problem for inpatient specialist palliative care.

Delirium is a common problem and cause of distress among patients with palliative care needs. The focus to date has been on managing the patient with agitated, hyperactive delirium, as these patients are very noticeable within the palliative care setting. This study in two parts shows that palliative care patients with agitated delirium are a minority of the total proportion of those with delirium. Part I: 100 acute admissions to a specialist palliative care unit were assessed and while 29% were found to have delirium, 86% of these had the hypoactive subtype of delirium. We also demonstrated a positive correlation between high ratings on a depression screening tool and delirium severity ratings. Part II: 8 specialist palliative care units took part in a point prevalence study of delirium over a 48-hour period. One hundred and nine patients were assessed and while 29.4% of these inpatients had delirium, 78% of them had the hypoactive subtype. Patients with hypoactive delirium may be much less noticeable or may be misdiagnosed as having depression or fatigue and the results of this study would advocate the routine use of delirium screening tools in all palliative care settings.