The US population of adults aged 65 years and older will double within the next 20 years. This aging population includes many adults who use hospital care extensively. In 2005, an estimated 35 million nonfederal hospital discharges occurred in the United States excluding newborns, and while older adults (65+) comprise 12% of the population, they accounted for 35% of hospital stays and increasingly often enter through the emergency room. For example, for patients 80 years and older, 55% were admitted through the emergency room in 1997 compared with 64% in 2002.
Risk of intensive care unit (ICU) admission and ICU utilization also rise with age, peaking in the very old: in those aged 85 years or more there were 58.2 admissions per 1000 individuals and 195.8 days per 1000 individuals, compared with 3.8 admissions per 1000 individuals and 11.5 days per 1000 individuals in those 18 to 44 years old. Individuals 85 years old and older were 3.75 times more likely to be admitted to the ICU than those aged 18 to 44 years after controlling for comorbid illness. Risk of ICU admission rates increased with admission to surgical unit, and presence of multiple comorbid illnesses especially cardiovascular and renal disease. Risk of death is increased among elderly patient nearly 25% of all hospital deaths occurred in patients over 85 years old.
Normal aging reduces physiologic reserve and the ability to maintain homeostasis under physiologic stress even in the best of circumstances. Chronic disease, the stress of acute illness precipitating admission, and polypharmacy add to vulnerability in this heterogeneous population. Furthermore, the hospital experience disrupts normal life rhythms in a foreign environment away from familiar cues. Hospital procedures and policies enforce dependency and immobility that is often related to physical restraints; expose the patient to multiple unfamiliar people involved in direct patient care, further exacerbated by unit transfers. The hospital setting disrupts sleep and nutrition due to lighting, unit noise, and interruptions such as frequent blood drawing, performance of vital signs and tests. Use of sedatives or medications with anticholinergic side effects —sometimes unavoidable during general anesthesia — and inadequate pain management further exacerbate the risk of hospital acquired complications, including delirium, depression, infection, malnutrition, deconditioning, falls, and pressure ulcers. Adverse outcomes include death, a prolonged hospital stay, nursing home placement and increased long-term dependency.
The incidence of delirium during hospitalization ranges from 11% to 42% and functional deficits related to delirium may persist long after hospital discharge. Even in patients admitted for cardiovascular disease rather than infection or dehydration, delirium is associated with higher unexpected in-hospital death which is also an important quality measure. Studies have shown that 30% to 60% of older people develop new dependencies in activities of daily living (ADL) during their hospital stay. Pressure ulcers, considered a preventable complication of hospitalization, are also associated with increased length of stay and health care cost, to the point that ...