Clinical Geriatrics

In addition to saving older adults’ lives, the prevention and treatment of delirium may lower their risks of lasting cognitive impairment, Sharon K. Inouye, MD, MPH, told an audience of more than 1500 geriatrics healthcare professionals during the AGS’ Annual Scientific Meeting in May. Dr. Inouye, the winner of the AGS’ 2010 Edward Henderson State-of-the-Art Award, delivered the meeting’s Henderson State-of-the-Art Lecture, which focused on her seminal research concerning delirium and functional decline in older people. “Delirium may provide the unique opportunity for early intervention and prevention of permanent cognitive damage,” Dr. Inouye noted.

The Director of the Aging Brain Center, Hebrew SeniorLife, and a Professor of Medicine at Harvard Medical School, Dr. Inouye has published more than 140 papers on delirium—an acute, temporary change in cognition characterized by relatively rapid onset and variable symptoms, including difficulty maintaining attention. Dr. Inouye also holds the Milton and Shirley F. Levy Family Chair at Hebrew SeniorLife’s Institute for Aging Research.

In addition to developing a highly effective screening protocol for delirium—the Confusion Assessment Method (CAM)—she and colleagues have also developed a multifaceted intervention strategy, the Hospital Elder Life Program (HELP), to prevent delirium by targeting risk factors for the syndrome. In the first study to show that a substantial number of cases of delirium are preventable, the intervention reduced risks of delirium by nearly 40% and cut healthcare costs significantly. The HELP model, which has also been shown to substantially reduce the incidence of falls in the hospital among seniors, is now being disseminated internationally. It is in use at more than 60 sites in six countries.

Often overlooked, delirium is common among older adults in institutional settings, Dr. Inouye noted in her lecture. The prevalence of delirium among those admitted to the hospital is as high as 24% and in-hospital incidence rates can reach 65%. Delirium is associated with high mortality both during hospitalization and post-discharge. One year after discharge, the mortality rate ranges from 35% to 40%. Hospital costs alone total $8 billion nationwide. And the tab for post-hospital costs are even higher—roughly $100 billion for institutionalization, rehabilitation, home care services, and caregiver burden. Total costs attributable to delirium range from $16,000 to $64,000 per patient.

“With the aging of the population, this is a problem that will continue to increase unless we can find good ways to manage it, and we can’t manage delirium and reduce complications unless we can recognize it,” said Dr. Inouye, who cited a study finding that only 31% of delirium cases among older adults were recognized.

Understanding, Preventing, Diagnosing, and Managing Delirium
Delirium is much more likely to be overlooked in patients with advanced age, vision impairment, the hypoactive form of delirium (which manifests as sleepiness), and dementia, Dr. Inouye explained. CAM, which has a sensitivity rate of 94% and a specificity rate of 89%, focuses on key characteristics of delirium: acute onset and fluctuating course; inattention; disorganized thinking; and altered levels of consciousness. A diagnosis of delirium requires the presence of the first two characteristics and either the third or the fourth, she noted, adding that CAM can provide a quick and accurate diagnosis and has helped to improve the recognition of delirium worldwide. “[Even so] we don’t recommend using it as a diagnostic tool, but rather, as a screening tool and then confirming the diagnosis with other means,” added Dr. Inouye, who suggests follow-up with a formal cognitive test such as the Mini-Cog, Montreal Cognitive Assessment, or Modified Mini-Mental State Examination.