Unplanned hospitalizations may be a bigger risk for long-term cognitive decline in older adults than previously thought.
A new study from Rush University Medical Center reveals that emergency and urgent hospitalizations are linked to an increased rate of cognitive decline in older adults far greater than previously recognized.
The research team presented their findings Monday at the Alzheimer’s Association International Conference. They analyzed data of 930 older adults, 75% of whom were female and an average of 81, who were enrolled in the Rush Memory and Aging Project in Chicago.
The study involved annual cognitive assessments and clinical evaluations. Researchers obtained information on their hospitalizations by linking records of 1999 to 2010 Medicare claims to their data from the project. Hospital admissions were designated as either elective or nonelective (which included emergencies and admissions for conditions that required immediate attention).
More than 600 of the older adults were hospitalized at least once over an average of almost five years of observation. Of those who were hospitalized, 260 (28%) had at least one elective hospital admission, and 553 (60%) had at least one nonelective hospital admission. Two hundred of the participants (22%) had both types of hospitalizations.
Nonelective hospitalizations were associated with an approximately 60% acceleration in the rate of cognitive decline from before hospitalization. Elective hospitalizations, however, were not associated with acceleration in the rate of decline at all.
“We found that those who have nonelective hospitalizations and who have not previously been diagnosed with dementia or Alzheimer’s disease had a rapid decline in cognitive function compared to the prehospital rates,” Bryan James, Ph.D., an epidemiologist in the Rush Alzheimer’s Disease Center and an assistant professor in the Rush Department of Internal Medicine, in the study announcement. “By comparison, people who were never hospitalized and those who had elective hospitalizations did not experience the drastic decline in cognitive function.”
The findings have important implications for the medical decision-making and care of older adults, James said. “While recognizing that all medical procedures carry some degree of risk, this study implies that planned hospital encounters may not be as dangerous to the cognitive health of older persons as emergency or urgent situations.”
This work expands upon previous research, which has shown that after being hospitalized, older adults are at high risk for memory and other cognitive problems, including both transient (temporary) delirium and long-term changes in cognition, including dementia. Forty percent of all hospitalized patients in the U.S. in October 2010 were age 65 and older, according to the Healthcare Cost and Utilization Project. Therefore, James said, hospitalization may be an underrecognized risk factor for cognitive decline and dementia for a large number of older adults that deserves more attention.