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Sleep in dementia and caregiving – assessment and treatment implications: a review

Published online by Cambridge University Press:  15 October 2010

David R. Lee  and
Alan J. Thomas
David R. Lee*
Affiliation:
Wolfson Research Centre, Institute for Ageing and Health, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, U.K.
Alan J. Thomas
Affiliation:
Wolfson Research Centre, Institute for Ageing and Health, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, U.K.
*
Correspondence should be addressed to: Dr. David R Lee, Senior Research Associate, Wolfson Research Centre, Institute for Ageing and Health, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, NE4 5PL, U.K. Phone: +44 191 248 1331; Fax: +44 191 248 1301. Email: D.R.Lee@newcastle.ac.uk.
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Abstract

Background: The increasing prevalence of dementia will precipitate a significant burden in terms of the costs of caring for people with dementia over the next 30 years; sleep disturbances in dementia are an important factor contributing to this burden.

Methods: We reviewed sleep disturbances in people with dementia and their carers and describe the various diagnostic, assessment and treatment strategies available to physicians in the management of this clinically significant problem.

Results: Sleep disturbances in people with dementia and their carers (i) are highly prevalent; (ii) impact significantly on quality of life of both people with dementia and their carers; (iii) increase the rate of cognitive decline; and (iv) accelerate the breakdown of community-based care. The training of physicians in the assessment and treatment of sleep disturbances in dementia and caregiving is scant despite a wide range of assessment strategies and treatment approaches, which comprise both pharmacological (including hypnotic/sedative medications) and non-pharmacological approaches (including: environmental; psychobehavioral; exercise and activity; and multi-component interventions). Specific diagnostic criteria for sleep disturbances in people with dementia and their carers remain lacking despite established criteria for general insomnia. Further to this, proposed changes to diagnostic criteria for DSM-V do not include a specific focus for the diagnosis and management of sleep disturbances in people with dementia or their carers.

Conclusions: This review suggests that the improved training of physicians to meet the needs of these vulnerable groups of older people is a priority, especially in the context of a rapidly increasing demand for accurate, early diagnosis and efficient management of sleep disturbance in these groups.

Keywords

insomniaelderlycognitive impairmentcarerdiagnosistreatmentassessmenttraining
Type
Review Article
Information
International Psychogeriatrics , Volume 23 , Issue 2 , March 2011 , pp. 190 - 201
Copyright
Copyright © International Psychogeriatric Association 2010

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References

Alessi, C. A. et al. (1995). Does physical activity improve sleep in impaired nursing home residents? Journal of the American Geriatrics Society, 43, 1098–1102.CrossRefGoogle ScholarPubMed
Alessi, C. A., Yoon, E. J., Schnelle, J. F., Al-Samarri, N. R. and Cruise, P. A. (1999). A randomized trial of a combined physical activity and environmental intervention in nursing home residents: do sleep and agitation improve? Journal of the American Geriatrics Society, 47, 784–791.CrossRefGoogle ScholarPubMed
Allen, S. R., Seiler, W. O., Stahelen, H. B. and Speigel, R. (1987). Seventy-two hour polygraphic and behavioural recordings of wakefulness and sleep in a hospital geriatric unit: comparison between demented and non-demented patients. Sleep, 10, 143–159.CrossRefGoogle Scholar
Alzheimer's Society (2007). Dementia UK Full Report. Available at: http://alzheimers.org.uk/site/scripts/download_info.php?fileID=2; last accessed 9 June 2010.Google Scholar
American Sleep Disorders Association (ASDA) (1995). Practice parameters for the use of actigraphy in the clinical assessment of sleep disorders. Sleep, 18, 285–287.CrossRefGoogle Scholar
Ancoli-Israel, S. (2005). Sleep and aging: prevalence of disturbed sleep and treatment considerations in older adults. Journal of Clinical Psychiatry, 66 (Suppl. 9), 24–30.Google ScholarPubMed
Ancoli-Israel, S. et al. (1997). Variations in circadian rhythms of activity, sleep, and light exposure related to dementia in nursing home patients. Sleep, 20, 18–23.Google ScholarPubMed
Ancoli-Israel, S., Martin, J. L., Kripke, D. F., Marler, M. and Klauber, M. R. (2002). Effect of light treatment on sleep and circadian rhythms in demented nursing home patients. Journal of the American Geriatrics Society, 50, 282–289.CrossRefGoogle ScholarPubMed
Banerjee, S. (2009). The Use of Antipsychotic Medication for People with Dementia: Time for Action. London: Department of Health.Google Scholar
Beaudreau, S. A. et al. (2008). The relationship between objectively measured sleep disturbance and dementia family caregiver distress and burden. Journal of Geriatric Psychiatry and Neurology, 21, 159–165.CrossRefGoogle ScholarPubMed
Beaulieu-Bonneau, S. and Hudon, C. (2009). Sleep disturbances in older adults with mild cognitive impairment. International Psychogeriatrics, 21, 654–666.CrossRefGoogle ScholarPubMed
Benca, R. M. (2005). Diagnosis and treatment of chronic insomnia: a review. Psychiatry Services, 56, 332–343.CrossRefGoogle ScholarPubMed
Bliwise, D. L. (2004). Sleep disorders in Alzheimer's disease and other dementias. Clinical Cornerstone, 6 (Suppl. 1A), S16–S28.CrossRefGoogle ScholarPubMed
Bliwise, D. L., Carroll, J. S., Lee, K. A., Nekich, J. C. and Dement, W. C. (1993). Sleep and “sundowning” in nursing home patients with dementia. Psychiatry Research, 48, 277–292.CrossRefGoogle ScholarPubMed
Bloom, H. G. et al. (2009). Evidence-based recommendations for the assessment and management of sleep disorders in older persons. Journal of the American Geriatric Society, 57 (5), 761–789.CrossRefGoogle ScholarPubMed
Boddy, F., Rowan, E. N., Lett, D., O'Brien, J. T., McKeith, I. G. and Burn, D. J. (2007). Subjectively reported sleep quality and excessive daytime somnolence in Parkinson's disease with and without dementia, dementia with Lewy bodies and Alzheimer's disease. International Journal of Geriatric Psychiatry, 22, 529–535.CrossRefGoogle ScholarPubMed
Boeve, B. F. et al. (1998). REM sleep behavior disorder and degenerative dementia: an association likely reflecting Lewy body disease. Neurology, 51, 363–370.CrossRefGoogle ScholarPubMed
Buysse, D. J., Reynolds, C. F. III, Monk, T. H., Berman, S. R. and Kupfer, D. J. (1989). The Pittsburgh Sleep Quality Index: a new instrument for psychiatric practice and research. Psychiatry Research, 28, 193–213.CrossRefGoogle ScholarPubMed
Carlander, B., Touchon, J., Ondze, B. and Billiard, M. (1996). REM sleep behavior disorder induced by cholinergic treatment in Alzheimer's Disease. Journal of Sleep Research, 5, 28.Google Scholar
Chenier, M. C. (1997). Review and analysis of caregiver burden and nursing home placement. Geriatric Nursing, 18, 121–126.CrossRefGoogle ScholarPubMed
Dauvilliers, Y. (2007). Insomnia in patients with neurodegenerative conditions. Sleep Medicine, 8, S27–S34.CrossRefGoogle ScholarPubMed
Duran, J. C., Greenspan, A., Diago, J. I., Gallego, R. and Martinez, G. (2005). Evaluation of risperidone in the treatment of behavioral and psychological symptoms and sleep disturbances associated with dementia. International Psychogeriatrics, 17, 591–604.CrossRefGoogle ScholarPubMed
Ebly, E. M., Hoban, D. B. and Rockwood, K. (1999). Living alone with dementia. Dementia and Geriatric Cognitive Disorders, 10, 541–548.CrossRefGoogle ScholarPubMed
Edinger, J. D. and Sampson, W. S. (2003). A primary care “friendly” cognitive behavioral insomnia therapy. Sleep, 26, 177–182.CrossRefGoogle ScholarPubMed
Ferri, C. P. et al. (2005). Global prevalence of dementia: a Delphi consensus study. Lancet, 366, 2112–2117.CrossRefGoogle ScholarPubMed
Fetveit, A. and Bjorvatn, B. (2004). The effects of bright light therapy on actigraphically measured sleep last for several weeks post-treatment: a study in a nursing home population. Journal of Sleep Research, 13, 153–158.CrossRefGoogle Scholar
Fetveit, A., Skjerve, A. and Bjorvatn, B. (2003). Bright light treatment improves sleep in institutionalized elderly: an open trial. International Journal of Geriatric Psychiatry, 18, 520–526.CrossRefGoogle ScholarPubMed
Gallagher-Thompson, D., Brooks, J. O., Bliwise, D. L., Leader, J. and Yesavage, J. A. (1992). The relations among caregiver stress, sundowning symptoms and cognitive decline in Alzheimer's disease. Journal of the American Geriatrics Society, 40, 807–810.CrossRefGoogle ScholarPubMed
Gilhooley, M. (1984). The social dimensions of senile dementia. In Hanley, I. and Hodge, J. (eds.), Psychological Approaches to the Care of the Elderly (pp. 88–135). London: Croom Helm.Google Scholar
Gilleard, C. (1984). Living with Dementia. London: Croom Helm.Google Scholar
Gjerstad, M., Boeve, B., Wentzel-Larsen, T., Aarsland, D. and Larsen, J. P. (2008). Occurrence and clinical correlates of REM sleep behaviour disorder in patients with Parkinson's disease over time. Journal of Neurology, Neurosurgery and Psychiatry, 79, 387–391.CrossRefGoogle ScholarPubMed
Harper, D. G., Stopa, E. G., McKee, A. C., Satlin, A., Harlan, P. C., Goldstein, R., and Volicer, L. (2001). Differential circadian rhythm disturbances in men with Alzheimer's Disease and frontotemporal degeneration. Archives of General Psychiatry 58, 353–360.CrossRefGoogle ScholarPubMed
Harper, D. G., Stopa, E. G., McKee, A. C., Satlin, A., Fish, D., and Volicer, L. (2004). Dementia severity and Lewy bodies affect circadian rhythms in Alzheimer's disease. Neurobiology of Ageing, 25, 771–781.CrossRefGoogle Scholar
Hinchcliffe, A., Hyman, I. and Blizard, B. (1992). The impact on carers of behavioural difficulties in dementia: a pilot study on management. International Journal of Geriatric Psychiatry, 7, 579–583.CrossRefGoogle Scholar
Jackson, S., Ham, R. J. and Wilkinson, D. (2004). The safety and tolerability of donezepil in patients with Alzheimer's Disease. British Journal of Clinical Pharmacology, 58, S1–S8.CrossRefGoogle Scholar
Jacobs, G., Pace-Schott, E. F., Stickgold, R. and Otto, M. W. (2004). Cognitive behavior therapy and pharmacotherapy for insomnia: a randomized controlled trial and direct comparison. Archives of Internal Medicine, 164, 1888–1896.CrossRefGoogle ScholarPubMed
Jeste, D. et al. (2010). Neurocognitive disorders: a proposal from the DSM-5 Neurocognitive Disorders Work Group. American Psychiatric Association. Available at: www.dsm5.org/Proposed%20Revision%20Attachments/APA%20Neurocognitive%20Disorders%20Proposal%20for%20DSM-5.pdf; last accessed 5 July 2010.Google Scholar
Johns, M. W. (1991). A new method for measuring daytime sleepiness: the Epworth Sleepiness Scale. Sleep 14, 540–545.CrossRefGoogle ScholarPubMed
Kesselring, A., Krulik, T. and Bischel, M. (2001). Emotional and physical demands on caregivers in home care to the elderly in Switzerland and their relationship to nursing home admission. European Journal of Public Health, 11, 267–273.CrossRefGoogle Scholar
King, A. C., Baumann, K., O'Sullivan, P., Wilcox, S. and Castro, C. (2002). Effects of moderate-intensity exercise on physiological, behavioral and emotional responses to family caregiving: a randomized controlled trial. Journal of Gerontology: Medical Sciences, 57A, M26–M36.Google Scholar
Klein, D. et al. (1999). Wandering behaviour in community residing persons with dementia. International Journal of Geriatric Psychiatry, 14, 272–279.3.0.CO;2-P>CrossRefGoogle ScholarPubMed
Kverno, K. S., Rabins, P. V., Blass, D. M., Hicks, K. and Black, B. S. (2008). Prevalence and treatment of neuropsychiatric symptoms in hospice-eligible nursing home residents with advanced dementia. Journal of Gerontological Nursing, 34, 8–17.CrossRefGoogle Scholar
Kverno, K. S., Black, B. S., Nolan, M. T. and Rabins, P. V. (2009). Research on treating neuropsychiatric symptoms of advanced dementia with non-pharmacological strategies, 1998–2008: a systematic literature review. International Psychogeriatrics, 21, 825–843.CrossRefGoogle ScholarPubMed
Landi, F., Russo, A. and Bernabei, R. (2004). Physical activity and behaviour in the elderly: a pilot study. Archives of Gerontology and Geriatrics, 9 (Suppl.), 235–241.CrossRefGoogle Scholar
Lee, D. R. (2008). Health-related quality of life in dementia caregiving: relationships with sleep quality and daytime sleepiness. Primary Care and Community Psychiatry, 13, 119–125.Google Scholar
Lee, D. R., Morgan, K. and Lindesay, J. E. B. (2007). Impact of institutional respite care on the sleep quality of people with dementia and their primary caregivers. Journal of the American Geriatrics Society, 55, 252–258.CrossRefGoogle Scholar
Livingston, G., Manela, M. and Katona, C. (1996). Depression and other psychiatric morbidity in carers of elderly people living at home. BMJ, 312, 153–156.CrossRefGoogle ScholarPubMed
Lyketsos, C. G., Lindell Veile, L., Baker, A. and Steele, C. (1999). A randomised controlled trial of bright light therapy for agitated behaviours in dementia patients residing in long term care. International Journal of Geriatric Psychiatry, 14, 520–526.3.0.CO;2-M>CrossRefGoogle ScholarPubMed
Mallon, L., Broman, J.-E. and Hetta, J. (2009). Is usage of hypnotics associated with mortality? Sleep Medicine, 10, 279–286.CrossRefGoogle ScholarPubMed
Martin, J., Marler, M., Shochat, T. and Ancoli-Israel, S. (2000). Circadian rhythms in institutionalized patients with Alzheimer's disease. Chronobiology International, 17, 405–418.CrossRefGoogle ScholarPubMed
Massironi, G., Galluzzi, S. and Frisoni, G. B. (2003). Drug treatment of REM sleep behavior disorders in dementia with Lewy bodies. International Psychogeriatrics, 15, 377–383.CrossRefGoogle ScholarPubMed
McCurry, S. M., Reynolds III, C., Ancoli-Israel, S., Teri, L. and Vitiello, M. (2000). Treatment of sleep disturbance in Alzheimer's disease. Sleep Medicine Reviews, 4, 603–628.CrossRefGoogle ScholarPubMed
McCurry, S. M., Gibbons, L. E., Logsdon, R. G., Vitiello, M. V. and Teri, L. (2005). Night-time insomnia treatment and education for Alzheimer's disease: a randomized controlled trial. Journal of the American Geriatrics Society, 53, 793–802.CrossRefGoogle Scholar
McCurry, S. M., Vitiello, M. V. and Gibbons, L. E. (2006). Factors associated with caregiver reports of sleep disturbances in persons with dementia. American Journal of Geriatric Psychiatry, 14, 112–120.CrossRefGoogle ScholarPubMed
McCurry, S. M., Logsdon, R. G., Teri, L. and Vitiello, M. V. (2007). Sleep disturbances in caregivers of persons with dementia: contributing factors and treatment implications. Sleep Medicine Reviews, 11, 143–153.CrossRefGoogle ScholarPubMed
Meehan, K. M. et al. (2002). Comparison of rapidly acting intramuscular olanzapine, lorazepam and placebo: a double blind randomized study in acutely agitated patients with dementia. Neuropsychopharmacology, 26, 494–504.CrossRefGoogle ScholarPubMed
Meguro, K. et al. (1995). Sleep disturbance in elderly patients with cognitive impairment, decreased daily activity and periventricular white matter lesions. Sleep, 18, 109–114.CrossRefGoogle ScholarPubMed
Meltzer, L. J., Phillips, C. and Mindell, J. A. (2009). Clinical psychology training in sleep and sleep disorders. Journal of Clinical Psychology, 65, 305–318.CrossRefGoogle ScholarPubMed
Miranda-Castillo, C., Woods, B. and Orrell, M. (2010). People with dementia living alone: what are their needs and what kind of support are they receiving? International Psychogeriatrics, 22, 607–617.CrossRefGoogle ScholarPubMed
Monti, J. M. and Monti, D. (2000). Role of dorsal raphe nucleus serotonin 5HT-1A receptor in the regulation of REM sleep. Life Sciences, 66, 1999–2012.CrossRefGoogle Scholar
Morin, C. M., Hauri, P. J., Espie, C. A., Speilman, A. J., Buysee, D. J. and Bootzin, R. R. (1999). Nonpharmacologic treatment of chronic insomnia: an American Academy of Sleep Medicine review. Sleep, 22, 1134–1156.CrossRefGoogle ScholarPubMed
Motohashi, Y., Maeda, A., Wakamatsu, H., Higuchi, S. and Yuasa, T. (2000). Circadian rhythm abnormalities of wrist activity of institutionalized dependent elderly persons with dementia. Journal of Gerontology, A: Biological Sciences and Medical Sciences, 55, M740–M743.Google ScholarPubMed
Naylor, E. et al. (2000). Daily social and physical activity increases slow-wave sleep and daytime neuropsychological performance in the elderly. Sleep, 23, 87–95.CrossRefGoogle ScholarPubMed
Nieoullon, A., Bentue-Ferrer, D., Bordet, R., Tsolaki, M. and Förstl, H. (2008). Importance of circadian rhythmicity in the cholinergic treatment of Alzheimer's disease: focus on galantamine. Current Medical Research and Opinion, 24, 3357–3367.CrossRefGoogle ScholarPubMed
Ouslander, J. G., Connell, B. R., Bliwise, D. L., Endeshaw, Y., Griffiths, P. and Schnelle, J. F. (2006). A nonpharmacological intervention to improve sleep in nursing home patients: results of a controlled clinical trial. Journal of the American Geriatrics Society, 54, 38–47.CrossRefGoogle ScholarPubMed
Papp, K. K., Penrod, C. E. and Strohl, K. P. (2002). Knowledge and attitudes of primary care physicians toward sleep and sleep disorders. Sleep and Breathing, 6, 103–109.CrossRefGoogle ScholarPubMed
Peretz-Lloret, S., Rossi, M., Nouzeilles, M., Trenkwalder, C., Cardinali, D. P. and Merello, M. (2009). Parkinson's disease sleep scale, sleep logs and actigraphy in the evaluation of sleep in parkinsonian patients. Journal of Neurology, 256, 1480–1484.CrossRefGoogle Scholar
Pollak, C. P. and Perlick, D. (1991). Sleep problems and institutionalisation of the elderly. Journal of Geriatric Psychiatry and Neurology, 4, 204–210.CrossRefGoogle ScholarPubMed
Pollak, C. P. and Stokes, P. E. (1997). Circadian rest-activity rhythms in demented and nondemented older community residents and their carers. Journal of the American Geriatrics Society, 45, 446–452.CrossRefGoogle Scholar
Prinz, P. N., Vitiello, M. V., Bokan, J., Kukull, W. A., Russo, J. and Vitaliano, P. (1987). Sleep in Alzheimer's dementia. Interdisciplinary Topics of Gerontology, 22, 128–143.CrossRefGoogle Scholar
Profenno, L. A. and Tariot, P. N. (2004). Pharmacologic management of agitation in Alzheimer's disease. Dementia Geriatrics and Cognitive Disorders, 17, 65–77.CrossRefGoogle ScholarPubMed
Rindlisbacher, P. and Hopkins, R. W. (1992). An investigation of the sundowning syndrome. International Journal of Geriatric Psychiatry, 7, 15–23.CrossRefGoogle Scholar
Ringman, J. M. and Simmons, J. H. (2000). Treatment of REM sleep behavior disorder with donezepil: a report of three cases. Neurology, 55, 870–871.CrossRefGoogle Scholar
Rongve, A., Boeve, B. F. and Aarsland, D. (2010). Frequency and correlates of caregiver-reported sleep disturbances in a sample of persons with early dementia. Journal of the American Geriatrics Society, 58, 480–486.CrossRefGoogle Scholar
Rosen, R. C., Rosekind, M. and Rosevear, C. (1993). Physician education in sleep and sleep disorders: a national survey of US medical schools. Sleep, 16, 249–254.CrossRefGoogle ScholarPubMed
Sanford, J. R. A. (1975). Tolerance of debility in elderly dependants by supporters at home: its significance for hospital practice. British Medical Journal, 3, 471–473.CrossRefGoogle ScholarPubMed
Schnelle, J. F., Alessi, C. A., Al-Samarrai, N. R., Fricker, R. D. and Ouslander, J. G. (1999). The nursing home at night: Effects of an intervention on noise, light and sleep. Journal of the American Geriatrics Society, 47, 430–438.CrossRefGoogle ScholarPubMed
Schenck, C. H. and Mahowald, M. W. (2002). REM-sleep behaviour disorder: clinical, developmental and neuroscience perspectives 16 years after its formal identification in SLEEP. Sleep, 25, 120–138.CrossRefGoogle ScholarPubMed
Schenk, C. H., Bundlie, S. R., Ettinger, M. G. and Mahowald, M. W. (1986). Chronic behavioural disorders of human REM sleep: a new category of parasomnia. Sleep, 9, 293–308.CrossRefGoogle Scholar
Schenck, C. H., Hurwitz, T. D. and Mahowald, M. W. (1993). REM-sleep behaviour disorder–an update on a series of 96 patients and a review of the world literature. Journal of Sleep Research, 2, 224–231.CrossRefGoogle Scholar
Singer, C. et al. (2003). Alzheimer's disease cooperative study: a multicentre, placebo-controlled trial of melatonin for sleep disturbance in Alzheimer's disease. Sleep, 26, 893–901.CrossRefGoogle Scholar
Sink, K. M., Holden, F. H. and Yaffe, K. (2005). Pharmacological treatment of neuropsychiatric symptoms of dementia: a review of the evidence. JAMA, 293, 596–608.CrossRefGoogle ScholarPubMed
Sloane, P. D. et al. (2007). High-intensity environmental light in dementia: effect on sleep and activity. Journal of the American Geriatrics Society, 55, 1524–1533.CrossRefGoogle ScholarPubMed
Spijker, A. et al. (2008). Effectiveness of nonpharmacological interventions in delaying the institutionalization of patients with dementia: a meta analysis. Journal of the American Geriatrics Society, 56, 1116–1128.CrossRefGoogle ScholarPubMed
Spira, A. P. et al. (2010). Sleep and physical functioning in family caregivers of older adults with memory impairment. International Psychogeriatrics, 22, 306–311.CrossRefGoogle ScholarPubMed
Sultzer, D. L., Gray, K. F., Gunay, I., Berisford, M. A. and Mahler, M. E. (1997). A double blind comparison of trazodone and haloperidol for treatment of agitation in patients with dementia. American Journal of Geriatric Psychiatry, 5, 60–69.CrossRefGoogle ScholarPubMed
Teri, L. et al. (2000). Treatment of agitation in AD: a randomized, placebo-controlled clinical trial. Neurology, 55, 1271–1278.CrossRefGoogle Scholar
Uchiyama, M. et al. (1995). Incidental Lewy-body disease in a patient with REM-sleep behaviour disorder. Neurology, 45, 709–712.CrossRefGoogle Scholar
Vitiello, M., Bliwise, D. L. and Prinz, P. (1992). Sleep in Alzheimer's disease and the sundown syndrome. Neurology, 42 (Suppl. 6), 83–93.Google ScholarPubMed
Wilcox, S. and King, A. C. (1999). Sleep complaints in older women who are family caregivers. Journal of Gerontology: Psychological Sciences, 54B, 189–198.CrossRefGoogle Scholar
Wilson, S. and Nutt, D. (2007). Management of insomnia: treatments and mechanisms. British Journal of Psychiatry, 191, 195–197.CrossRefGoogle Scholar
Wimo, A., Winblad, B. and Jonsson, B. (2007). An estimate of the total worldwide societal costs of dementia in 2005. Alzheimer's and Dementia, 3, 81–91.CrossRefGoogle ScholarPubMed
Witting, W., Kwa, I. H., Eikelenboom, P., Mirmiran, M. and Swaab, D. F. (1990). Alterations in the circadian rest-activity rhythm in aging and Alzheimer's disease. Biological Psychiatry, 27, 563–572.CrossRefGoogle ScholarPubMed
Yesavage, J. A. et al. (2003). Development of diagnostic criteria for defining sleep disturbance in Alzheimer's disease. Journal of Geriatric Psychiatry and Neurology, 16, 131–139.CrossRefGoogle ScholarPubMed
Ying-Hui, W. and Swaab, D. F. (2007). Disturbance and strategies for reactivation of the circadian rhythm system in ageing and Alzheimer's disease. Sleep Medicine, 8, 623–626.Google Scholar