Association of Hospitalization with Long‐Term Cognitive Trajectories in Older Adults

IMPORTANCE Hospitalizations are associated with cognitive decline in older adults. OBJECTIVE To determine the association between hospitalization characteristics and the trajectory of cognitive function in older adults. DESIGN Population‐based longitudinal study of cognitive aging. SETTING Olmsted Medical Center and Mayo Clinic, the only centers in Olmsted County, Minnesota, with hospitalization capacity. PARTICIPANTS Individuals without dementia at baseline, with consecutive cognitive assessments from 2004 through 2017, and at least one visit after the age of 60. MEASUREMENTS The primary outcome was longitudinal changes in global cognitive z‐score. Secondary outcomes were changes in four cognitive domains: memory, attention/executive function, language, and visuospatial skills. Hospitalization characteristics analyzed included elective versus nonelective, medical versus surgical, critical care versus no critical care admission, and long versus short duration admissions. RESULTS Of 4,587 participants, 1,622 had 1 and more hospital admission. Before hospitalization, the average slope of the global z‐score was −0.031 units/year. After hospitalization, the rate of annual global z‐score accelerated by −0.051 (95% CI = −0.057, −0.045) units, P