In 2001, approximately 12.6 million individuals aged 65 and older were discharged from American hospitals with an average length of stay of 5.8 days1 and up to 66% of them suffered from cognitive impairment (CI)2–20. CI in hospitalized older adults includes a variety of disorders ranging from mild cognitive deficit, delirium, to full-blown dementia. Dementia is a syndrome of decline in memory plus at least one other cognitive domain, such as language, visuo-spatial, or executive function sufficient to interfere with social or occupational functioning in an alert person21. Delirium is a disturbance of consciousness with reduced ability to focus, sustain, or shift attention that occurs over a short period of time and tends to fluctuate over the course of the day22. Mild cognitive impairment without dementia is defined as the presence of a cognitive deficit in the absence of delirium that does not affect functional performance23.
Hospitalized older adults with CI are vulnerable to hospital complications including delirium, physical restraints, urinary catheters, and tethers2,3,24–35. The management of their medical or surgical illnesses requires avoiding certain medications with anticholinergic activities that might worsen cognition36. Furthermore, CI may delay diagnostic and therapeutic procedures, demand more time for informed-consent related issues, and result in difficulty in adherence to medical recommendations37,38. The special needs of hospitalized older adults with delirium and dementia has been shown to increase demands on nursing staff, risk of post-discharge institutionalization, length of stay and health care costs3–10,27,39–48. We wanted to look specifically at CI because it often goes undetected49–51 and can have a great impact on the hospital course of elders.
Screening for CI among hospitalized older adults has been considered to have potential benefit in hospital care of older adults52. Screening may lead to early detection by uncovering subtle symptoms not yet apparent to families or other caregivers who know the patient well but do not notice small declines or changes in day-to-day functioning. Early recognition of CI may lead to early treatment and subsequently may delay progression of cognitive decline improve health outcomes. Screening may enhance physician’s prescribing practices and reduce exposure to harmful medications among these vulnerable patients. Finally, delirium is an important prognostic indicator and screening patients could provide invaluable information towards the overall clinical picture. Despite all of this, the current literature does not provide sufficient information to support the use of routine screening on admission2–20,41,52–54. Most of the published studies were conducted among elders who stayed in the hospital for more than 48 hours, missing data on the crucial first 48 hours of the hospital course2–20,41,52–54. These studies did not evaluate the impact of unrecognized CI on the hospital course and the majority of these studies were not conducted in the urban and lower socioeconomic status populations of elders that are the most vulnerable for bad health outcomes2–20,41,52–54. Finally, few studies evaluated the impact of delirium superimposed on cognitive impairment on the hospital course and mortality of elders2–20,41,52–54.
With these details in mind we wanted to explore the impact of cognitive impairment recognition among patients aged 65 and older admitted to the medical services of an urban, public hospital in Indianapolis to determine the prevalence and the impact of recognized and unrecognized CI on the hospital course of these elders. Furthermore, we examined the role of delirium superimposed on these hospitalized elders with CI.