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Delirium accelerates cognitive decline in Alzheimer disease
Fong TG, Jones RN, Shi P, Marcantonio ER, Yap L, Rudolph JL, Yang FM, Kiely DK et al.. Neurology, 2009-05-01
Topic: Amyloid, tau and blood-test diagnosis
Objective To examine the impact of delirium on the trajectory of cognitive function in a cohort of patients with Alzheimer disease (AD). Methods A secondary analysis of data collected from a large prospective cohort, the Massachusetts Alzheimer's Disease Research Center's patient registry, examined cognitive performance over time in patients who developed (n = 72) or did not develop (n = 336) delirium during the course of their illnesses. Cognitive performance was measured by change in score on the Information-Memory-Concentration (IMC) subtest of the Blessed Dementia Rating Scale. Delirium was identified using a previously validated chart review method. Using linear mixed regression models, rates of cognitive change were calculated, controlling for age, sex, education, comorbid medical diagnoses, family history of dementia, dementia severity score, and duration of symptoms before diagnosis. Results A significant acceleration in the slope of cognitive decline occurs following an episode of delirium. Among patients who developed delirium, the average decline at baseline for performance on the IMC was 2.5 points per year, but after an episode of delirium there was further decline to an average of 4.9 points per year (p = 0.001). Across groups, the rate of change in IMC score occurred about three times faster in those who had delirium compared to those who did not. Conclusions Delirium can accelerate the trajectory of cognitive decline in patients with Alzheimer disease (AD). The information from this study provides the foundation for future randomized intervention studies to determine whether prevention of delirium might ameliorate or delay cognitive decline in patients with AD.
Key findings
- Results A significant acceleration in the slope of cognitive decline occurs following an episode of delirium.
- Across groups, the rate of change in IMC score occurred about three times faster in those who had delirium compared to those who did not.
Why it matters
In this cohort of patients with Alzheimer's disease, an episode of delirium was followed by a significant acceleration in cognitive decline, with decline occurring about three times faster than in those without delirium. This suggests that preventing or managing delirium may help slow decline, but it does not show a cure or prevention for Alzheimer's disease.
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Study details
- Study designprospective cohort
- Participants72
- Evidence strengthHigh
How this study scored 71/100
Published in a leading specialty journal, and it is a prospective cohort study, followed forward from enrollment. Scored zero for effect reported and randomised / blinded because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 9 / 10 | Tier 2 — leading specialty journal (Neurology) |
| Journal's citation record | 4 / 4 | Neurology: journal h-index 525 (OpenAlex, 2026-10-29) |
| Study design | 7 / 12 | A prospective cohort study, followed forward from enrollment |
| Strength of evidence | 5 / 5 | Rated “high” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2009 — within 20 year(s) of the newest study here |
| Sample size | 1 / 4 | 72 participants |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 3 / 3 | Studied in people (participant count stated) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | 6 / 7 | Cited 495 times (OpenAlex, 2026-10-10) |
| Citations per year | 4 / 5 | 26.1 citations a year over 19 year(s) since 2009 |
| Impact for its field and year | 4 / 6 | Cited 15.7× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 3 / 6 | Cited by 20 other studies in this library |
| Still being cited | 3 / 4 | Cited 82 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author Sharon K. Inouye: h-index 118 (OpenAlex, whole career) |
| Institution's track record | 3 / 3 | Harvard University: institution h-index 3,235 (OpenAlex) |
| Multi-centre collaboration | 2 / 3 | OpenAlex lists 5 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 19414723) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 71 / 100 | — |
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Read the original
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Cite this study APA, Vancouver, BibTeX · download .bib or .ris
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. The record's author list ends in “et al.”, so not every author is named. Check the citation against the original before you use it.
APA 7th
Fong, T. G., Jones, R. N., Shi, P., Marcantonio, E. R., Yap, L., Rudolph, J. L., et al. (2009). Delirium accelerates cognitive decline in Alzheimer disease. Neurology. https://doi.org/10.1212/wnl.0b013e3181a4129a
Vancouver
Fong TG, Jones RN, Shi P, Marcantonio ER, Yap L, Rudolph JL, et al. Delirium accelerates cognitive decline in Alzheimer disease. Neurology. 2009. doi:10.1212/wnl.0b013e3181a4129a. PMID: 19414723.
BibTeX
@article{fong2009-19414723,
author = {Fong, T. G. and Jones, R. N. and Shi, P. and Marcantonio, E. R. and Yap, L. and Rudolph, J. L. and Yang, F. M. and Kiely, D. K. and others},
title = {{Delirium accelerates cognitive decline in Alzheimer disease}},
journal = {Neurology},
year = {2009},
doi = {10.1212/wnl.0b013e3181a4129a},
pmid = {19414723},
url = {https://doi.org/10.1212/wnl.0b013e3181a4129a}
}
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