ICU stays linked to a doubling of dementia risk

Chicago, United States – Seniors who have spent time in an intensive care unit (ICU) are twice as likely to develop dementia in the future as seniors who have never been to an ICU, according to a news study. Findings to be presented at the Alzheimer’s Association International Conference (AAIC) 2022 ^[1].

“Hospitalization in an intensive care unit may be an unrecognized risk factor for dementia in older adults,” Medscape Medical News told Medscape Medical News. Bryan D JamesPhD, an epidemiologist at the Rush Alzheimer’s Disease Center, Chicago, Illinois.

“Healthcare professionals caring for older patients who have been hospitalized with serious illnesses should be prepared to assess and monitor their patients’ cognitive status as part of their long-term care,” added Mr James.

A hidden risk factor?

The study showed that hospitalization in an intensive care unit after a serious illness is related to subsequent cognitive decline in elderly patients (Alzheimer’s disease or other age-related dementias). However, it is not known by what mechanisms.

“Given the high rate of intensive care hospitalizations among older adults, particularly during the COVID-19 pandemic, it is critical to explore this link,” said Bryan D. James.

Rush’s team evaluated the impact of an intensive care unit stay on dementia risk in 3,822 older adults (mean age 77 years) without known dementia at baseline and who participated in five diverse epidemiological cohorts.

The participants were screened annually for the development of Alzheimer’s disease and all types of dementia using standardized cognitive assessments.

During an average of 7.8 years, 1,991 (52%) adults experienced at least one stay in an ICU; 1031 (27%) had experienced one in an ICU prior to study recruitment; and 961 (25%) experienced such an ICU stay during the study period.

In models adjusted for age, sex, education, and race, ICU hospitalization was associated with a 63% increased risk of Alzheimer’s dementia (hazard ratio [RR] 1.63; 95% CI, 1.41 – 1.88) and a 71% increased risk of dementia of all types (RR, 1.71; 95% CI, 1.48 – 1.97).

In models adjusted for other factors, such as risk factors and vascular disease, other chronic medical conditions, and functional disability, the association was even stronger: Hospitalization in intensive care was associated with an approximately two-fold increased risk for dementia of Alzheimer’s (HR, 2.10; 95% CI, 1.66-2.65); and dementia of all types (HR, 2.20; 95% CI, 1.75-2.77).

James told Medscape Medical News that it’s not clear why a stay in intensive care might increase dementia risk.

“This study was not designed to assess the causes of the increased risk of dementia in people who had been hospitalized in intensive care. However, the researchers looked at a number of factors that could explain this increased risk,” he explained.

One is the serious illness itself, which led to hospitalization, and which could lead to brain damage; For example, severe Covid-19 has been shown to directly damage the brain, Bryan D. James said.

He also noted that certain specific events that occur during an intensive care unit stay increase the risk of cognitive decline, including infection and severe sepsis, acute dialysis, neurological dysfunction and delirium, as well as sedation.

important work

Speaking about the study for Medscape Medical News, heather snyderPhD, vice president of medical and scientific relations for the Alzheimer’s Association, said the value of this study is that it looks at people who are in intensive care, regardless of cause.

“This is very important, especially considering the increase in the number of people, especially those aged 60 and over, who have been in an intensive care unit in the last two years.

“If a person has been in an intensive care unit, their doctor or health care provider should be told,” Dr. Snyder advised.

The article originally appeared on Medscape.fr with the headline ICU remains linked to doubling of dementia risk. Translated and completed by Stéphanie Lavaud.

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