question: PURPOSE To determine the prevalence of disability among ICU survivors one year after admission, and which factors influence functional outcome. METHODS We examined consecutive patients enrolled in the population-based Mayo Clinic Olmsted Study of Aging and then admitted to medical or surgical adult ICUs at Mayo Clinic, Rochester between January 1, 2006, and December 31, 2014 to determine one-year functional outcomes. RESULTS 831cases were included. Mean age was 84 years (IQR 79-88). 569 (68.5%) patients were alive one year after ICU admission. Of them, 546 patients had functional assessment at one year and 367 (67.2%) had good functional outcome. On multivariable analysis, poor one-year functional outcome (death or disability) was more common among women, older patients, and patients with baseline cognitive impairment (mild cognitive impairment or dementia), higher Carlson scores, and longer ICU stay (all P <.01). After excluding deceased patients, these associations remained unchanged. In addition, 120 (32.3%) of 372 patients who had post-ICU cognitive evaluation experienced cognitive decline after the ICU admission. CONCLUSIONS On a population-based cohort of older, predominantly elderly patients, approximately two-thirds of survivors maintained or regained good functional status 1 year after ICU hospitalization. However, older age, female sex, greater comorbidities, abnormal baseline cognition, and longer ICU stay were associated with poor functional recovery and cognitive decline was common.