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DLB fluctuations: specific features that reliably differentiate DLB from AD and normal aging
Ferman TJ, Smith GE, Boeve BF, Ivnik RJ, Petersen RC, Knopman D, Graff-Radford N, Parisi J et al.. Neurology, 2004-01-01
Topic: Risk, prevention and care in population studies
Objective To determine whether certain aspects of fluctuations reliably distinguish dementia with Lewy bodies (DLB) from Alzheimer's disease (AD) and normal aging. Methods Participants included 200 community-dwelling cognitively normal elderly persons, 70 DLB patients, and 70 AD patients with collateral informants. A 19-item questionnaire was administered to the informants that queried about symptoms of fluctuations and delirium. Results Fluctuations occur infrequently in nondemented elderly persons aged 58 to 98 years. In contrast, four characteristics of fluctuations were found to significantly differentiate AD from DLB. These composite features include daytime drowsiness and lethargy, daytime sleep of 2 or more hours, staring into space for long periods, and episodes of disorganized speech. The presence of three or four features of this composite occurred in 63% of DLB patients compared with 12% of AD patients and 0.5% of normal elderly persons. Informant endorsement of three or four of these items yielded a positive predictive value of 83% for the clinical diagnosis of DLB against an alternate diagnosis of AD. Endorsement of fewer than three items had a negative predictive value of 70% for the absence of a clinical diagnosis of DLB in favor of AD. The authors present evidence of test-retest reliability, convergent validity, and empirical verification with a separate cross-validation sample. Fluctuations were not associated with any particular combination of hallucinations, parkinsonism, or REM sleep behavior disorder. Conclusions Based on informant report, disturbed arousal and disorganized speech are specific aspects of fluctuations in dementia with Lewy bodies that reliably distinguish dementia with Lewy bodies from Alzheimer's disease and normal aging.
Key findings
- Results Fluctuations occur infrequently in nondemented elderly persons aged 58 to 98 years.
- In contrast, four characteristics of fluctuations were found to significantly differentiate AD from DLB.
- The presence of three or four features of this composite occurred in 63% of DLB patients compared with 12% of AD patients and 0.5% of normal elderly persons.
- Fluctuations were not associated with any particular combination of hallucinations, parkinsonism, or REM sleep behavior disorder.
Why it matters
Family members or carers of 70 people with dementia with Lewy bodies (DLB), 70 with Alzheimer's disease and 200 healthy older adults answered a questionnaire about "fluctuations". Four features stood out: daytime drowsiness and lethargy, daytime sleep of 2 or more hours, staring into space for long periods, and episodes of disorganized speech. Three or four of them were reported for 63% of people with DLB, 12% with Alzheimer's and 0.5% of healthy adults. When three or four were reported, the clinical diagnosis was DLB rather than Alzheimer's 83% of the time. This is a diagnostic aid based on what carers report. It is not a test on its own, and it says nothing about treatment.
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Study details
- Participants200
- Effect size0.5%
- Evidence strengthLow
How this study scored 61/100
Published in a leading specialty journal. Scored zero for study design 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 | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2004 — older than 20 years, still counted |
| Sample size | 2 / 4 | 200 participants |
| Effect reported | 2 / 3 | Effect reported as a number, without an interval or test |
| 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 463 times (OpenAlex, 2026-10-10) |
| Citations per year | 3 / 5 | 19.3 citations a year over 24 year(s) since 2004 |
| Impact for its field and year | 4 / 6 | Cited 9.1× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 4 / 6 | Cited by 35 other studies in this library |
| Still being cited | 3 / 4 | Cited 75 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 4 / 4 | Last-listed author Dennis W. Dickson: h-index 218 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | Mayo Clinic: institution h-index 1,606 (OpenAlex) |
| Multi-centre collaboration | 1 / 3 | OpenAlex lists 2 institution(s) in 1 country |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 14745051) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 61 / 100 | — |
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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
Ferman, T. J., Smith, G. E., Boeve, B. F., Ivnik, R. J., Petersen, R. C., Knopman, D., et al. (2004). DLB fluctuations: specific features that reliably differentiate DLB from AD and normal aging. Neurology. https://doi.org/10.1212/wnl.62.2.181
Vancouver
Ferman TJ, Smith GE, Boeve BF, Ivnik RJ, Petersen RC, Knopman D, et al. DLB fluctuations: specific features that reliably differentiate DLB from AD and normal aging. Neurology. 2004. doi:10.1212/wnl.62.2.181. PMID: 14745051.
BibTeX
@article{ferman2004-14745051,
author = {Ferman, T. J. and Smith, G. E. and Boeve, B. F. and Ivnik, R. J. and Petersen, R. C. and Knopman, D. and Graff-Radford, N. and Parisi, J. and others},
title = {{DLB fluctuations: specific features that reliably differentiate DLB from AD and normal aging}},
journal = {Neurology},
year = {2004},
doi = {10.1212/wnl.62.2.181},
pmid = {14745051},
url = {https://doi.org/10.1212/wnl.62.2.181}
}
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