Actigraphy Motion Biosensors for Alzheimer’s Studies
Alzheimer’s disease is a cognitive impairment, but it can manifest itself in many detrimental ways. These include alterations in daytime activity levels, sleep quality, and awake/sleep patterns. These effects of the disease are often the aspects that are most disturbing to the caregivers4and are therefore reasonable endpoints for testing the efficacy of therapies3. For example, Mahlberg et al. used actigraphy to show a decrease in daytime activity in response to a therapy designed to reduce agitation6.
Activity and sleep can also be markers for cognitive symptoms. Zeitzer et al. showed that patient apathy was highly correlated with a specific daytime activity pattern that was independent of depression7. Carvalho-Bos used actigraphy to show that the instability of the patient’s daily awake/sleep rhythm was related to cognitive decline 2 , and Buchman et al. showed that the level of 5 Galik EM, Resnick B, Gruber-Baldini A, Nahm E, Pearson K, Pretzer- Aboff I. Pilot testing of the restorative care intervention for the activity was associated with the onset of Alzheimer’s disease in a four-year prospective study of 716 older subjects 1 .
1 Buchman AS, Boyle PA,Yu L, Shah RC,Wilson RS, Bennett DA. Total daily physical activity and the risk of AD and cognitive decline in older adults. Neurology 2012; 78:1323-1329.
2 Carvalho-Bos SS, Riemersma-van der Lek R,Waterhouse J, Reilly T, Van Someren EJW. Strong association of the rest-activity rhythm with wellbeing in demented elderly women. Am J Geriatr Psychiatry 2007; 15: 92-100.
3 David R, Mulin E, Mallea P, Robert PH. Measurement of neuro- psychiatric symptoms in clinical trials targeting Alzheimer’s Disease and related disorders. Pharmaceuticals 2010; 3: 2387-2397.
4 FriedmanL,SpiraAP,HernandezB,MatherC,SheikhJ,Ancoli-Israel S,Yesavage JA, Zeitzer JM. Brief morning light treatment for sleep/wake disturbances in older memory-impaired individuals and their caregivers. Sleep Medicine 2012; 13:546-549
6. Mahlberg R,Walther S, Eichmann U,Tracik F, Kunz D. Effects of rivastigmine on actigraphically monitored motor activity in severe agitation related to Alzheimer’s disease: A placebo-controlled pilot study. Arch Geront Geriatrics. 2007; 45: 19-26.
7. Zeitzer JM, David R, Friedman L, Mulin E, Garcia R,Wang J,Yesavage JA, Robert PH, Shannon W. Phenotyping apathy in individuals with Alzheimer’s disease using functional principal component analysis. Am. J. Geriatr Psychiatry 2013; 21: 391-397.
