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Updated: May 26, 2026
09:17
Using Retinal Imaging to Study Dementia
Published on: November 6, 2017
Delirium and Increased Risk of Developing Dementia: An Emulated Target Trial Analysis
Cara S Rathmell1, Haoqi Sun2, Wendong Ge3
1Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, USA.
Medrxiv : the Preprint Server for Health Sciences
|May 25, 2026
Summary
Hospitalization with delirium significantly increases the risk of developing Alzheimer's Disease and Related Dementias (ADRD) within two years for older adults. This study used causal inference to confirm the strong association.
Area of Science:
- Gerontology
- Neurology
- Epidemiology
Background:
- Bidirectional links between delirium and Alzheimer's Disease and Related Dementias (ADRD) are suggested by multiple studies.
- Previous research established a strong association but lacked causal inference from observational data to minimize bias.
Purpose of the Study:
- To estimate the effect of in-hospital delirium on the cumulative incidence of ADRD over two years post-hospitalization in patients aged 65 and older.
- To utilize statistical causal inference methods on electronic medical record data for a robust analysis.
Main Methods:
- An emulated clinical trial design was employed using observational data from Mass General Brigham Electronic Medical Record (EMR) between April 2017 and September 2019.
- Statistical causal survival analysis, including inverse propensity weighting (IPW) and g-formula, was used to adjust for confounding, censoring, competing risks, and immortal-time bias.
- Included 5901 patients aged 65+ with no prior dementia diagnosis or medication history within 12 months pre-admission.
Main Results:
- At two years post-admission, the adjusted cumulative incidence of ADRD was 20.2% (95% CI 13.2-27.9%) for patients who experienced delirium during hospitalization.
- In contrast, the cumulative incidence of ADRD was 7.6% (95% CI 4.0-12.1%) for patients who did not experience delirium, as calculated by the IPW method.
Conclusions:
- The findings from this emulated trial provide strong evidence for an association between delirium during hospitalization and an increased risk of developing ADRD in older adults within two years.
- Delirium experienced during hospitalization is a significant risk factor for subsequent ADRD development in the elderly population.
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