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A randomized, controlled trial of bright light therapy for agitated behaviors in dementia patients residing in long-term care
Lyketsos CG, Lindell Veiel L, Baker A, Steele C.. International journal of geriatric psychiatry, 1999-07-01
Topic: Risk, prevention and care in population studies
Background Agitated behaviors are common in dementia patients residing in chronic care settings. Their occurrence may be associated with lack of adequate exposure to sunlight and with circadian rhythm disturbances. Objective Prior research has suggested that bright light therapy (BLT) may reduce agitated behaviors in dementia patients. The aim of this study was to test the efficacy of BLT in a randomized, controlled, crossover clinical trial. Method Fifteen patients with dementia and agitated behaviors residing in a chronic care facility were randomized in a crossover design to morning BLT for 1 hour per day or to a control condition with dim light exposure. Patients were treated in either condition for 4 weeks, followed by 1 week on no treatment, prior to being crossed over to the other condition. Results Eight out of 15 patients completed the entire study. The rest completed at least 2 weeks of study. Patients randomized to the BLT condition exhibited a statistically significant improvement in nocturnal sleep from a mean of 6.4 hours/night to 8.1 hours/night 4 weeks later (p Conclusion Patients with dementia in chronic care who exhibit agitated behaviors sleep more hours at night when administered morning BLT. However, BLT does not lead to improvements in agitated behaviors in institutionalized patients with dementia with non-disturbed sleep-wake cycles.
Cite this study APA, Vancouver, BibTeX · download .bib or .ris
APA 7th
Lyketsos, C. G., Lindell Veiel, L., Baker, A., & Steele, C. (1999). A randomized, controlled trial of bright light therapy for agitated behaviors in dementia patients residing in long-term care. International journal of geriatric psychiatry. https://doi.org/10.1002/(sici)1099-1166(199907)14:7<520::aid-gps983>3.0.co;2-m
Vancouver
Lyketsos CG, Lindell Veiel L, Baker A, Steele C. A randomized, controlled trial of bright light therapy for agitated behaviors in dementia patients residing in long-term care. International journal of geriatric psychiatry. 1999. doi:10.1002/(sici)1099-1166(199907)14:7<520::aid-gps983>3.0.co;2-m. PMID: 10440971.
BibTeX
@article{lyketsos1999-10440971,
author = {Lyketsos, C. G. and Lindell Veiel, L. and Baker, A. and Steele, C.},
title = {{A randomized, controlled trial of bright light therapy for agitated behaviors in dementia patients residing in long-term care}},
journal = {International journal of geriatric psychiatry},
year = {1999},
doi = {10.1002/(sici)1099-1166(199907)14:7<520::aid-gps983>3.0.co;2-m},
pmid = {10440971},
url = {https://doi.org/10.1002/(sici)1099-1166(199907)14:7<520::aid-gps983>3.0.co;2-m}
}
Built from the record alzhub holds for this paper, not looked up. Volume, issue and page numbers are not held in the record. Check the citation against the original before you use it.
Key findings
- Their occurrence may be associated with lack of adequate exposure to sunlight and with circadian rhythm disturbances.
- Objective Prior research has suggested that bright light therapy (BLT) may reduce agitated behaviors in dementia patients.
- Results Eight out of 15 patients completed the entire study.
- Patients randomized to the BLT condition exhibited a statistically significant improvement in nocturnal sleep from a mean of 6.4 hours/night to 8.1 hours/night 4 weeks later (p<0.05).
Why it matters
In this small crossover trial, morning bright light therapy helped patients with dementia sleep more at night but did not improve agitated behaviors. This means bright light may help sleep but not agitation in this setting.
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Study details
- Participants15
- Evidence strengthHigh
How this study scored 59/100
Published in a peer-reviewed journal, and it is a randomised controlled trial. Scored zero for effect reported because the record does not state it.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (International journal of geriatric psychiatry) |
| Journal's citation record | 2 / 4 | International Journal of Geriatric Psychiatry: journal h-index 190 (OpenAlex, 2026-10-29) |
| Study design | 11 / 12 | A randomised controlled trial (from PubMed type “Randomized Controlled Trial”) |
| 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 | 1999 — older than 20 years, still counted |
| Sample size | 1 / 4 | 15 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 | 1 / 2 | Randomised (as stated in the record) |
| Times cited | 5 / 7 | Cited 210 times (OpenAlex, 2026-10-10) |
| Citations per year | 2 / 5 | 7.2 citations a year over 29 year(s) since 1999 |
| Impact for its field and year | 3 / 6 | Cited 3.8× the average for papers of its field and year (OpenAlex FWCI) |
| Cited by studies here | 1 / 6 | Cited by 1 other studies in this library |
| Still being cited | 1 / 4 | Cited 10 times in 2024–2026 (2026 still in progress; OpenAlex) |
| Senior author's track record | 2 / 4 | Last-listed author Cynthia Steele: h-index 27 (OpenAlex, whole career) |
| Institution's track record | 2 / 3 | Johns Hopkins University: institution h-index 2,306 (OpenAlex) |
| Multi-centre collaboration | 0 / 3 | OpenAlex lists 1 institution(s) in 1 country — scores zero (affiliation lists can be incomplete) |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 10440971) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Total | 59 / 100 | — |
What each of these 20 components measures, and what this score is not →
Read the original
- DOI: 10.1002/(sici)1099-1166(199907)14:7<520::aid-gps983>3.0.co;2-m
- PubMed: 10440971
- Original source →
May need a subscription Unpaywall, Europe PMC and OpenAlex found no free copy of the full text (checked 10 Oct 2026), so the publisher may charge for it. The PubMed abstract is free.
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