Delirium symptoms in post-acute care: prevalent, persistent, and associated with poor functional recovery.

Objectives: To determine the prevalence of delirium symptoms at the time of admission to post-acute facilities, the persistence of delirium symptoms in this setting, and the association of delirium symptoms with functional recovery.

Design: Prospective cohort study.

Setting: Eighty-five post-acute care facilities: 55 rehabilitation hospitals and 30 skilled nursing facilities in 29 states.

Participants: Five hundred fifty-one consenting patients aged 65 and older newly admitted to participating facilities from acute care hospitals.

Measurements: Data were collected as part of a field study effort related to the Minimum Data Set (MDS). Basic demographic data, medical comorbidity, delirium symptoms, and functional status--activities of daily living (ADLs) and instrumental activities of daily living (IADLs)--were obtained from MDS assessments performed within 4 days of admission and again 1 week later by the patient's primary nurse. Six delirium symptoms (easily distracted, periods of altered perception, disorganized speech, periods of restlessness, periods of lethargy, and mental function varies over the course of a day) were assessed after appropriate training.

Results: Of the 551 patients (mean age +/- standard deviation 78 +/- 7, 64% women), 126 had delirium symptoms on post-acute admission, for an overall prevalence of 23%. In patients with delirium symptoms on the admission assessment, 1 week later, 14% had completely resolved, 22% had fewer delirium symptoms, 52% had the same number of symptoms, and 12% had more symptoms. Of those with no delirium symptoms on admission, 4% had new symptoms 1 week later. Patients who had the same number of or more delirium symptoms at the second assessment had significantly worse ADL and IADL recovery than those with fewer or resolved delirium symptoms or those with no delirium symptoms at either assessment. Persistent delirium symptoms remained significantly associated with worse ADL and IADL recovery after adjusting for age, comorbidity, dementia, and baseline functional status.

Conclusions: The data from this study provide strong preliminary evidence that, in patients newly admitted to post-acute care facilities from acute care hospitals, delirium symptoms are prevalent, persistent, and associated with poor functional recovery. Educational efforts are warranted to help post-acute facility staff recognize and manage this common and morbid condition.