The main goal of this application is to add to the body of knowledge regarding the symptoms and sequelae of delirium in the post-acute care (PAC) setting by adding to and expanding upon an existing database of clinical characteristics and outcomes of patients admitted to PAC with delirium. Over the past 4 years we have been conducting a randomized clinical trial (RCT) of a Delirium Abatement Program (DAP) for patients admitted to eight Boston area post-acute skilled nursing facilities with the support of the National Institute on Aging. We have screened 8198 admissions, and enrolled 457 subjects (mean age 84 years, 65% women) into our trial, making it by far the largest cohort of delirious patients ever enrolled in a research study. Our goal with this application is to obtain support for additional secondary analyses (not among the primary or secondary outcomes of the original RCT) that inform the clinical epidemiology of delirium in post-acute care. The specific aims of this application are to: (1) Obtain longitudinal survival information on patients enrolled in our RCT by linking with the National Death Index, (2) Examine the association of persistent delirium, delirium symptoms, and delirium severity on long-term (4 year) survival following post-acute admission with delirium. Additionally, we will pursue exploratory analyses probing the nature of the relationship of persistent delirium and mortality, examining closely differences in specific causes of death, and the possible moderating or mediating role of comorbidity. Addressing these aims will contribute substantially to the understanding of delirium in the PAC setting, and may be generalizable to other settings. Our study team includes the senior members participating in the ongoing RCT. Therefore, we are familiar with the context and structure of the data, and have already produced some secondary analyses based on this dataset. [unreadable] [unreadable]