Rest-Activity and Light
Exposure Patterns
in Older Adults:
Methodological Implications
Thomas Hornick MD
Patricia Higgins ...
Objectives
 Understand the influence of circadian rhythm
disruptions on overall health.
 Identify clinical characteristi...
Types of rhythms
1. Ultradian (heart beat, respirations, appetite)
2. Infradian (menstrual cycle)
3. Circannual (annual br...
Arendt 2006 4
With Zeitgeber
5
Disruption of circadian rhythm
• Poor performance/fatigue (Reinberg et al,
2007, Laposky et al 2008)
• Weight gain(Knutson...
Why older adults?
• Sleep disorders are common
• Complaints among caregivers of persons
with dementia frequently revolve a...
Aging and light
• Older adults spend much of their time in
muted indoor lighting.
• 35 minutes/day of bright light exposur...
Age related losses in retinal
illumination
Turner et al Br J Ophthalmol. 2008
November; 92(11): 1439–1444 9
.
Wikipedia, accessed 10/30/09
10
Role of Retinal Receptors
 Three known retinal receptors: process
visual and circadian timing information
 Rods and cone...
Turner et al Br J Ophthalmol. 2008
November; 92(11): 1439–1444
Spectral sensitivity of photopic, scotopic and
circadian (m...
iPRGCs: History
 1998: Melanopsin in light-sensitive cells on frog
skin (Provencio et al, Proc Natl Acad Sci )
 2000: Me...
Intrinsically photosensitive
retinal ganglion cells (iPRGCs)
Timing Photoreceptors
• Located throughout retina (~3000)
• E...
Suprachiasmatic nucleus
(SCN) is master
pacemaker
1. Activity in SCN correlates with circadian rhythms
2. Lesions of SCN a...
Role of Melatonin
 Melatonin
• Primary role in humans is to convey
information about the daily light-dark cycle to
physio...
Melatonin Rhythms and Aging
Zeitzer et al Sleep. 2007
November 1; 30(11): 1437–1443.
Average (±SEM) plasma melatonin in yo...
Plasma melatonin suppression by
bright light in 65 year old man
Duffy et al Neurobiol Aging.
2007 May; 28(5): 799–807.
Pla...
Melatonin suppression with
bright light
Duffy et al Neurobiol Aging.
2007 May; 28(5): 799–807.
Phase shift of fitted plasm...
Circadian light transfer function
Figueiro, et al. 2006
20
Clinical applications
21
Turner et al Br J Ophthalmol. 2008
November; 92(11): 1439–1444
22
Therapeutic light
 2 Hours bright light in AM
 Improved sleep efficiency in NH residents
 Fetveit et al, 2003
 30 minu...
Riemersma-van de Lek et al
JAMA 2008
 6/12 Homes randomized for lighting
intervention
 Installed fluorescent fixtures, b...
Riemersma-van der Lek, R. F. et al. JAMA 2008;299:2642-2655.
MMSE, Depression
25
Schedule change: Shift work
 Light at night (LAN)
 Nurses’ Health Study (Willet, PI)
 Effects of Light at Night on Circ...
Circadian phase shifters
 Can have negative effects on health
 Abrupt: jet lag, shift work
 Gradual: institutionalizati...
Circadian Lighting in Long-
term Care: A feasibility
study
28
Methods
 3 participants, residents of Ward 62B
 Lighting: GE fluorescent ceiling lamps
14,000 K
 Instruments
 Sleepwat...
Methods/Instrumentation for
Sleep/Light Data
 Subject wore Sleep
Watch-L© for 7 days
 Wrist-worn electronic
measure of b...
31
Lighting Installation
 VAMC safety standards
 1st phase: 3 ‘blue lamp’ prototypes by GE:
8000 Kelvin (K); 14,000K;16,000...
33
Mean of light measurements taken at eye level (horizontally)
at 8 points in the room in the 4 cardinal directions, using
P...
Results & Conclusions
 Wrist actigraph well accepted
 Light sensor on wrist covered much of the
time by clothing?
 New ...
Rest-Activity and Light
Exposure Patterns in the Home
Setting: A Methodological
Study
P. Higgins, T. Hornick, M. Figueiro
...
Purpose
 Assess the feasibility and reliability of
using a circadian light meter
(DaysimeterTM) in a field setting and us...
Dyad
 Caregiver – Wife, 73 years, “good health”, no
vision problems, no sleep-aid meds. Primary
caregiver
 Elder – Husba...
Methods
 Procedure - Light exposure and rest-
activity data were collected over 7
consecutive days in November, 2007
 In...
DaysimeterTM
 Research prototype
 Two light meters
measure photopic
and circadian light
exposure
 Actigraph measures
mo...
Results
41
Built Environment
 Independent living complex for seniors
 Apartment: 640 square feet
 Brown paneling and beige paint a...
Ambient light exposure/24 hrs
when out of bed (lux)
Light Norms (in lux)*
Sunlight
/reflective surfaces 150,000
Overcast D...
ACTIGRAPHY
Caregiver
wife
Demented
husband
Sleep-rest
- Mean sleep efficiency %
- Mean night sleep (mins)
- Mean sleep lat...
Caregiver
Elder
24-hour Sleep and Light
45
Caregiver
46
47
Entrained vs Disrupted
Entrained Disrupted
Human
Conclusions
 Daily light levels are very low
 Little variation in light levels
 Sleep
 Neither caregiver or elder slee...
Support
 VISN 10 GRECC, Cleveland VAMC
 Frances Payne Bolton School of Nursing,
Case Western Reserve University,
Clevela...
Team
 Tom Hornick, MD1,2
 Patricia Higgins, PhD1,2
 Mariana Figueiro, PhD3
 Mark Rea, PhD3
 Andy Bierman, MS3
 John ...
Next Steps
“Methodology issues in a tailored
light treatment for persons with
dementia" R01 – M. Figueiro, PI
51
Wikipedia, accessed 5/2010 52
53
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How Many Researchers Does It Take to Change Light Bulb?

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  • Biological rhythms are periodic biologic fluctuations that correspond to, or are in response to, environmental changeRhythms allow organisms to time events and anticipate change; i.e., rhythms allow organism to adapt to environmental change
  • Biological rhythms are endogenous but highly sensitive to environmental stimuli; i.e., light. The influence of light and darkness on circadian rhythms and related physiology and behavior through the SCN in humans
  • process visual and circadian timing information
  • Spectral sensitivity of photopic, scotopic and circadian (melatonin suppression) photoreception.57 Peak sensitivities of circadian, scotopic and photopic photoreception are 460 nm (blue), 506 nm (green) and 555 nm (green-yellow), respectively. Spectral absorptance is shown for 30D blue blocking (AcrySof SN60AT, Alcon Laboratories, Fort Worth, TX) and UV-only blocking (ClariFlex, Advanced Medical Optics, Santa Ana, CA) intraocular lenses (IOLs).8 The area between the two IOL curves is the violet, blue and green light blocked in comparison with a UV-only blocking IOL.
  • Average (±SEM) plasma melatonin in young (top, n=90) and older (bottom, n=29) subjects during a normally phased sleep episode (closed boxes) and a constant routine where they remained awake at the same clock hours (open circles). Data were aligned such that each subject's wake time was graphically adjusted to 08:00 and the data from the baseline day and night and from the CR expressed relative to wake time; sleep time is from 24:00 to 08:00. Melatonin data were averaged hourly within and then across subjects.
  • Plasma melatonin data from subject 19G7, a 65 year old man who was exposed to a 3,527 lux light stimulus. Upper panel: plasma melatonin data from the initial circadian phase estimation procedure (CR1); middle panel: plasma melatonin data from the intervention day, with the 6.5-h experimental light exposure indicated by the open box; lower panel: plasma melatonin data from the final circadian phase estimation procedure (CR2) shown in the solid symbols, with data from CR1 replotted from above in the open symbols. During CR1, the fitted peak of the melatonin secretion (MELmax) occurred at 03:45, 3.5 h before habitual wake time. During CR2 MELmax occurred at 06:30, a 3.5 h phase delay. Melatonin was suppressed by 78% during the 6.5-h 3,527 lux light stimulus.
  • Phase shift of fitted plasma melatonin peak (MELmax) vs. illuminance of experimental light stimulus. Data from each of the ten subjects are plotted individually and shown with square symbols. Solid line represents the 4-parameter logistic model fit to the data, with the 95% confidence interval of the model shown in the dotted lines. For comparison, the 4-parameter logistic model fit to the data from our previous study in younger adults [64] is shown in the dashed line.
  • Light levels in contemporary and natural environments3954–57 and also in phototherapy for seasonal affective disorder, which is typically 2500 lux for 2 h/day or 10 000 lux for 30 min/day.44Illuminances are given in units of photopiclux. Photopiclux accurately describe the effectiveness of a particular light exposure for overall cone photoreception, which has a peak sensitivity at 555 nm in the green–yellow part of the spectrum (cf, fig 1). A standard circadian lux unit is needed1040 but has not been adopted yet for comparing the effectiveness of different light exposures for circadian photoreception, which has peak sensitivity at 460 nm in the blue part of the spectrum (cf, fig 1).
  • ADLs improved Less irritability, less inability to sleep in those with the lighting.5%without decelerating the progressive cognitive worsening (as is also the case foracetylcholinesteraseinhibitors8).Light also reduced depressive symptoms by a relative 19% and attenuated the gradual increase in functional limitationsby53%.A similar increase in efficacy over time by 2% was found fo
  • 30 year study Evaluate light exposure in rotating shift workers based on the recent information on the specific wavelengths that affect melatonin levels in humans, and will relate those measures to the response of their circadian system, as measured by melatonin levels in urine. Specifically, we will measure light exposure by applying a new device, a circadian light meter that captures the short wavelength portion of visible light, which has been described to most strongly suppress melatonin levels and phase shift the circadian pace maker as part of the light's influence on non-image forming function in humans. Urine collections will be conducted during three of the overall 7 days of study period. Sample 180Approx 15 million shift workers in US: self selecting nurses, safety officers
  • Jet lag: Adjusting to new schedule can cause daytime sleepiness, insomnia, irritability, stomach upset
  • Regular lighting is 5000 Kelvin (color correlated temperature, hot body radiation)
  • Lux – SI unit of illuminance [human brightness perception] as measured by a light meter1 lux = 1 lumen/square meterTwo types of photoreceptors: Rods/cones ratio = ~10/1Photopic - brightness perceived by conesScotopic – brightness perceived by rods [more sensitive to bluish-white light]Historically, light meters measured eye’s cone sensitivity to lamps/lighting = photopic dataMore accurate measure combines the two [rods and cones] into a measure that more reflects what the human eye perceives in terms of light  S/P ratioStudies indicate that lighting that provides higher S/P ratio provides better visual acuityhttp://www.lightenergysource.com/Scotopic.htmVisual effectiveness: “a measure of how the appearance of information and the use of visual elements within it affect the ease with which users can find, understand, and use the information. Because most… users use their eyes to access your information, the visual impact of that information can be an important factor in its general quality.” http://proquest.safaribooksonline.com/0131477498/ch10
  • Per Daysimeter: caregiver phasor magnitude of 0.17[norms 0.5-0.6] Indication of circadian entrainment/disruption
  • How Many Researchers Does It Take to Change Light Bulb?

    1. 1. Rest-Activity and Light Exposure Patterns in Older Adults: Methodological Implications Thomas Hornick MD Patricia Higgins RN, PhD 1
    2. 2. Objectives  Understand the influence of circadian rhythm disruptions on overall health.  Identify clinical characteristics of circadian rhythm disturbances in older adults  Recognize the importance of chronobiology in elders’ sleep-wake disturbances.  Describe results from preliminary studies assessing the use of circadian light therapy in a nursing home unit and measurement of circadian light exposure in a case study of home-dwelling older adults. 2
    3. 3. Types of rhythms 1. Ultradian (heart beat, respirations, appetite) 2. Infradian (menstrual cycle) 3. Circannual (annual breeding cycles) 4. Circadian (sleep-wake cycle) Rhythms allow organisms to time events and anticipate change! Biological Rhythms 3
    4. 4. Arendt 2006 4
    5. 5. With Zeitgeber 5
    6. 6. Disruption of circadian rhythm • Poor performance/fatigue (Reinberg et al, 2007, Laposky et al 2008) • Weight gain(Knutson et al, 2007) • Breast cancer (Stevens et al 2001) • Other conditions 6
    7. 7. Why older adults? • Sleep disorders are common • Complaints among caregivers of persons with dementia frequently revolve around disordered day/night cycles • Medications for sleep are less safe in this population 7
    8. 8. Aging and light • Older adults spend much of their time in muted indoor lighting. • 35 minutes/day of bright light exposure compared to approximately 58 minutes of bright light per day for middle-aged adults. (Sanchez 1993) • Reduced light exposure compounded due to physiologic changes • senile meiosis, cataract formation, and/or increased light absorption by the crystalline lens. (Charmin 2003) • Attenuation of light exposure by more than 80% in normal older adults relative to young adults. 8
    9. 9. Age related losses in retinal illumination Turner et al Br J Ophthalmol. 2008 November; 92(11): 1439–1444 9
    10. 10. . Wikipedia, accessed 10/30/09 10
    11. 11. Role of Retinal Receptors  Three known retinal receptors: process visual and circadian timing information  Rods and cones: visual data  Intrinsically photosensitive retinal ganglion cells (iPRGC): primarily light-dark data 11
    12. 12. Turner et al Br J Ophthalmol. 2008 November; 92(11): 1439–1444 Spectral sensitivity of photopic, scotopic and circadian (melatonin suppression) photoreception 12
    13. 13. iPRGCs: History  1998: Melanopsin in light-sensitive cells on frog skin (Provencio et al, Proc Natl Acad Sci )  2000: Melanopsin-containing cells found in retinal ganglion cell layer (Provencio et al, J Neuroscience)  Most likely comprise the retinohypothalamic tract  Sensitive to wavelengths in the 484-500 nm (blue light)  2002: Light responses from melanopsin- containing ganglion cells in humans (Berson et al, Science) 13
    14. 14. Intrinsically photosensitive retinal ganglion cells (iPRGCs) Timing Photoreceptors • Located throughout retina (~3000) • Express melanopsin • Blue light sensitive(peak 460nm) • Regulate photoperiodism (sensitivity to length of day and night) • Higher excitatory threshold than rods/cones • Transmits to SCN 24-hour light-dark pattern on the retina is the most efficient stimulus for entrainment of circadian rhythms in humans 14
    15. 15. Suprachiasmatic nucleus (SCN) is master pacemaker 1. Activity in SCN correlates with circadian rhythms 2. Lesions of SCN abolish free-running rhythms 3. Isolated SCN continues to cycle 4. Transplanted SCN imparts rhythm of the donor on the host 5. SCN is known to be compromised in older adults with dementia. (Harper et al 2008) 15
    16. 16. Role of Melatonin  Melatonin • Primary role in humans is to convey information about the daily light-dark cycle to physiological systems • Peaks during sleep, suppressed by light. 16
    17. 17. Melatonin Rhythms and Aging Zeitzer et al Sleep. 2007 November 1; 30(11): 1437–1443. Average (±SEM) plasma melatonin in young (top, n=90) and older (bottom, n=29) subjects during a normally phased sleep episode (closed boxes) and a constant routine where they remained awake at the same clock hours (open circles). Data were aligned such that each subject's wake time was graphically adjusted to 08:00 and the data from the baseline day and night and from the CR(constant routine) expressed relative to wake time; sleep time is from 24:00 to 08:00. Melatonin data were averaged hourly within and then across subjects Age 65-81, mean 68 17
    18. 18. Plasma melatonin suppression by bright light in 65 year old man Duffy et al Neurobiol Aging. 2007 May; 28(5): 799–807. Plasma melatonin data from subject 19G7, a 65 year old man who was exposed to a 3,527 lux light stimulus. Upper panel: plasma melatonin data from the initial circadian phase estimation procedure (CR1); middle panel: plasma melatonin data from the intervention day, with the 6.5-h experimental light exposure indicated by the open box; lower panel: plasma melatonin data from the final circadian phase estimation procedure (CR2) shown in the solid symbols, with data from CR1 replotted from above in the open symbols. During CR1, the fitted peak of the melatonin secretion (MELmax) occurred at 03:45, 3.5 h before habitual wake time. During CR2 MELmax occurred at 06:30, a 3.5 h phase delay. Melatonin was suppressed by 78% during the 6.5-h 3,527 lux light stimulus. 18
    19. 19. Melatonin suppression with bright light Duffy et al Neurobiol Aging. 2007 May; 28(5): 799–807. Phase shift of fitted plasma melatonin peak (MELmax) vs. illuminance of experimental light stimulus. Data from each of the ten subjects are plotted individually and shown with square symbols. Solid line represents the 4- parameter logistic model fit to the data, with the 95% confidence interval of the model shown in the dotted lines. For comparison, the 4- parameter logistic model fit to the data from our previous study in younger adults [64] is shown in the dashed line. 19
    20. 20. Circadian light transfer function Figueiro, et al. 2006 20
    21. 21. Clinical applications 21
    22. 22. Turner et al Br J Ophthalmol. 2008 November; 92(11): 1439–1444 22
    23. 23. Therapeutic light  2 Hours bright light in AM  Improved sleep efficiency in NH residents  Fetveit et al, 2003  30 minutes sunlight for five days  Decreased napping  Increased participation  Alessi et al, 2005  Daytime bright light  Improved sleep/wake cycle in persons with dementia (van Someren et al,1997) 23
    24. 24. Riemersma-van de Lek et al JAMA 2008  6/12 Homes randomized for lighting intervention  Installed fluorescent fixtures, both real and sham  1000 lux horizontal at eyes in intervention  Caregivers unaware which arm randomized to  Melatonin randomized by patient  3.5 year follow up 24
    25. 25. Riemersma-van der Lek, R. F. et al. JAMA 2008;299:2642-2655. MMSE, Depression 25
    26. 26. Schedule change: Shift work  Light at night (LAN)  Nurses’ Health Study (Willet, PI)  Effects of Light at Night on Circadian System in Nurses (Schernhammer, PI, RO1-OH008171) 26
    27. 27. Circadian phase shifters  Can have negative effects on health  Abrupt: jet lag, shift work  Gradual: institutionalization  Timed light exposure: reset clock  Sensitivity age-related  Bright light in morning advances the clock  Bright light in evening delays the clock  Delays easier than advances 27
    28. 28. Circadian Lighting in Long- term Care: A feasibility study 28
    29. 29. Methods  3 participants, residents of Ward 62B  Lighting: GE fluorescent ceiling lamps 14,000 K  Instruments  Sleepwatch-L© (AMI, Ardsley, NY)  Neuropsychiatric Inventory-Nursing Home Version  DaysimeterTM (Lighting Research Center, Rensselear Polytechnic Institute) 29
    30. 30. Methods/Instrumentation for Sleep/Light Data  Subject wore Sleep Watch-L© for 7 days  Wrist-worn electronic measure of body movement and light  Software calculates activity/inactivity and light © Ambulatory Monitoring Inc 30
    31. 31. 31
    32. 32. Lighting Installation  VAMC safety standards  1st phase: 3 ‘blue lamp’ prototypes by GE: 8000 Kelvin (K); 14,000K;16,000K  2nd: 13 standard fluorescent lighting ceiling light fixtures in Dayroom  7 of 13 changed to 14,000 K (6 remained @ 5000 K)  Timer controlled blue lighting on, 8a-6p  Lighting after 6pm: sufficient for visual acuity 32
    33. 33. 33
    34. 34. Mean of light measurements taken at eye level (horizontally) at 8 points in the room in the 4 cardinal directions, using PMA 2200 Photoradiometer, SnP Meter Photopic SL3103- 001, S/N 9829 Light Conditions Photopic (cones) Lux Scotopic (rods) Lux S/P Ratio Brightness Visual Effectiveness all on 517 1178 2.24 781 1818 14,000 K only 381 918 2.26 606 759 standard 333 725 2.14 491 609 all off 222 489 2.17 328 412 34
    35. 35. Results & Conclusions  Wrist actigraph well accepted  Light sensor on wrist covered much of the time by clothing?  New blue lighting well received  3 subjects exposure to blue lighting (time in Dayroom/ 10 hr period):  77 minutes, 371 mins, 373 mins  Next time: Change installation pattern?, use DaysimeterTM 35
    36. 36. Rest-Activity and Light Exposure Patterns in the Home Setting: A Methodological Study P. Higgins, T. Hornick, M. Figueiro American J Alzheimer’s Disease and Other Dementias, 2010 36
    37. 37. Purpose  Assess the feasibility and reliability of using a circadian light meter (DaysimeterTM) in a field setting and use the human circadian phototransduction model’s analyses to provide clinically relevant results 37
    38. 38. Dyad  Caregiver – Wife, 73 years, “good health”, no vision problems, no sleep-aid meds. Primary caregiver  Elder – Husband, 80 years, vascular dementia plus multiple co-morbidities, continent, needed assistance for all ADL’s and IADL’s, multiple meds included antidepressant but no sleep-aid  Elder received all primary care from the Cleveland VA Geriatrics Clinical team. 38
    39. 39. Methods  Procedure - Light exposure and rest- activity data were collected over 7 consecutive days in November, 2007  Instruments  Assessment of sleep quality and habits  Home visit  Sleepwatch-L© (AMI, Ardsley, NY)  DaysimeterTM (Lighting Research Center, Rensselear Polytechnic Institute) 39
    40. 40. DaysimeterTM  Research prototype  Two light meters measure photopic and circadian light exposure  Actigraph measures movement 40
    41. 41. Results 41
    42. 42. Built Environment  Independent living complex for seniors  Apartment: 640 square feet  Brown paneling and beige paint and carpet  One south facing window in bedroom  Sliding glass door onto porch (south facing)  Standard florescent lighting: kitchen and bath  Incandescent lighting: floor and table lamps 42
    43. 43. Ambient light exposure/24 hrs when out of bed (lux) Light Norms (in lux)* Sunlight /reflective surfaces 150,000 Overcast Day 1,000 Avg nursing home 50 Avg living room 50-200 Twilight 10 Full Moon 1 *From Turner, 2008. Br J Opthalmology Range Mean mins: > 20 lux > 500 lux >1000 lux Elder 0-449 191.5 0.0 0.0 Caregiver 0-3990 635.5 18.0 8.0 Dyad data 43
    44. 44. ACTIGRAPHY Caregiver wife Demented husband Sleep-rest - Mean sleep efficiency % - Mean night sleep (mins) - Mean sleep latency (mins) - Mean wake after sleep onset [WASO] (mins) - Mean napping/24 hr (mins) 70 257 81 119 31 81 446 17 105 96 Intra-daily variability (0-2) 0.71 0.95 Inter-daily stability (0-1) 0.69 0.76 44
    45. 45. Caregiver Elder 24-hour Sleep and Light 45
    46. 46. Caregiver 46
    47. 47. 47 Entrained vs Disrupted Entrained Disrupted Human
    48. 48. Conclusions  Daily light levels are very low  Little variation in light levels  Sleep  Neither caregiver or elder sleep well  Caregiver: poor circadian entrainment  Sleep disruption causes  Low lighting, little contrast  Frequent wake times at night 48
    49. 49. Support  VISN 10 GRECC, Cleveland VAMC  Frances Payne Bolton School of Nursing, Case Western Reserve University, Cleveland, OH  Lighting Research Center, Rensselear Polytechnic Institute, Troy NY  General Electric Company, Nela Park, East Cleveland, OH 49
    50. 50. Team  Tom Hornick, MD1,2  Patricia Higgins, PhD1,2  Mariana Figueiro, PhD3  Mark Rea, PhD3  Andy Bierman, MS3  John Bullough, PhD3  Bill Biers, PhD4  Mark Duffy, PhD4  Ed Yandek, BS4  1Case Western Reserve University  2Cleveland Veterans Affairs Medical Center  3Lighting Research Center, Rensselaer Polytechnic Institute  4General Electric Lighting, Nela Park 50
    51. 51. Next Steps “Methodology issues in a tailored light treatment for persons with dementia" R01 – M. Figueiro, PI 51
    52. 52. Wikipedia, accessed 5/2010 52
    53. 53. 53

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