Predicting disability and death after the ICU

A growing number of older adults are surviving visits to hospital intensive care units (ICUs), but many emerge with disabilities such as impaired walking and poor overall function. A new study by Yale School of Medicine researchers shows that the level of disability the year before an ICU visit can predict post-ICU disability and death.

The results appear in the Feb. 9 issue of JAMA Internal Medicine.

First author Dr. Lauren Ferrante and her colleagues at Yale evaluated 291 participants who were admitted to an ICU over the 14+ years of the larger Precipitating Events Project (PEP) longitudinal study of adults aged 70 and older in Greater New Haven, Conn. All participants had monthly assessments of function, during which they were asked if they needed help to complete activities of daily living, such as bathing and dressing; instrumental activities of daily living, such as meal preparation and taking medications; and mobility activities, such as walking a quarter mile.

The team found that there were three distinct functional trajectories (or levels of disability) in the year before and after ICU admission. They determined the probability of an older person transitioning to a worse functional trajectory after an ICU admission, and also identified factors associated with death within one year of being admitted to the ICU.

"We calculated the probability of an older person transitioning to a worse functional trajectory in the ICU setting," said Ferrante, a senior fellow in the Pulmonary, Critical Care, and Sleep Medicine program, and a research fellow in the Geriatric Clinical Epidemiology and Aging-Related Research program at Yale. "We found that more than half of older persons transition to a worse functional trajectory or die within 30 days of admission." 

The team also found that the pre-ICU functional trajectories of mild-to-moderate and severe disability were associated with more than double and triple the risk of death within one year of ICU admission, respectively, compared to those with minimal disability.

Ferrante said this suggests the need for a focus on maintaining function in older adults in the ICU and after discharge, and for new rehabilitation strategies for these patients, particularly those who have transitioned to a worse functional trajectory. "Our results also suggest that older adults with severe disability in the year before ICU admission may want to consider a palliative approach while in the ICU," she added.