Recorded delirium in a national sample of elderly inpatients: potential implications for recognition

This retrospective study examined delirium and related confusional diagnoses recorded in patients older than age 60 discharged from Veterans Affairs (VA) acute inpatient units nationally in 1996 (n = 267,947). Only 4% of patients had delirium or related confusional diagnoses recorded. Patients with recorded delirium had significantly higher mortality than did those without recorded delirium or those with other confusional diagnoses ("organic psychoses"); the most common delirium types were dementia with delirium and alcohol intoxication/withdrawal delirium. Organic psychoses patients had the longest lengths of stay and significantly more admissions to nonmedical/surgical units and discharges to nursing homes; almost 20% were African American. The recorded rate of delirium in the VA health system likely underestimates true prevalence and possibly reflects nonrecognition of delirium in many older veterans. Certain motoric and etiologic types of delirium may be more commonly diagnosed and recorded. Future research should prospectively examine recognition of motoric and etiologic delirium subtypes and racial differences in delirium diagnoses.