A Study on the Health Benefits and Financial Merits of Circadian Light for Elder Care Patients

Sujatha Changolkar, Susannah Rogers

Professor John Whitman

HCMG 855: Management of Health Care for the Elderly

Final Project, Fall 2017

Keywords: circadian biology, circadian rhythm, long-term care, Alzheimer’s, dementia, depression, ADRD, Circadian Rhythm Light, WalaLight, non-pharmacological treatment

 Background Research


Sleep disturbances are associated increasingly with older demographics and are extremely common in people with Alzheimer’s disease or related dementia (ADRD).1 This is especially evident among individuals in long-term care, such as skilled-nursing, assisted-living, and rehabilitation facilities as well as retirement communities. Studies show that residents in long-term care spend approximately 40 percent of their night awake.2 This high rate of sleep disturbance and its associated deleterious impact on cognitive and physical capacity signals a key entry-point for improvements to quality of care in long-term healthcare settings.

This entry-point has grown increasingly clear in the past few years, wherein there has been a burgeoning interest and body of research in the scientific relationship between sleep and health. Specifically, the study of humans’ circadian clocks or rhythms, a field known as circadian biology, has become prominent.

Circadian biology research reveals the extremely strong effect of optimal circadian rhythms on biological and physiological performance. It is apparent that Alzheimer’s, depression, attention-deficit/hyperactivity disorder (ADHD), heart disease, obesity, diabetes and other metabolic issues are among the many conditions that are linked to circadian rhythms.3 Thus, with a strong causality between optimal circadian rhythm and health having been established, a specific entry-point into the market of long-term is mechanisms aimed at improving patients’ circadian rhythms.

A primary intervention is new designs and improvements to light schemas. Particularly, replacing white light-emitting diode (LED) lights that are common in healthcare facilities, which are high in bio-active blue wavelength content and shown to be harmful long-term,4 with a new product. Consistent with this belief, there is a lot of existing research as well as ongoing studies on light-therapy mechanisms and their effect on improving circadian rhythms and sleep efficiency. The focus of this paper is on one mechanism already on the market: WALALIGHT® Light.

The objectives of this paper are two-fold. First, to identify the rationales for long-term facilities to implement circadian rhythm-improving mechanisms by analyzing existing research. Second, to determine if WALALIGHT® Light is a viable non-pharmacological mechanism by analyzing a new set of data on patients in an elder care facility (Rydal Park, in Pennsylvania) pre- and post-exposure to WALALIGHT® Light; and secondary, to identify the health and fiscal assets of the product WALALIGHT® Light in this emerging market.

Existing Research on Light in Healthcare Settings

Numerous studies show that humans are extremely responsive to light as a stimulus, an effect that was under-recognized for many decades. In a study by the Center for Health Design in 2006, light was identified as a major mechanism in health in four modes:

  1. Enabling performance of visual tasks
  2. Controlling the body’s circadian system
  3. Affecting mood and perception
  4. Facilitating direct absorption for critical chemical reactions within the body5

This study thus effectively cites light schemas as an operator on humans’ cognitive (visual tasks, mood and perception) and biological (direct absorption, circadian systems) functions.

In a noteworthy 2013 study produced by Nicholas Hanford and Mariana Figuiero of the Lighting Research Center (LRC), the researchers manipulated levels of light exposures in a long-term care facility and saw a significant increased in sleep scores, in accordance to the measures of Pittsburgh Sleep Quality.6 After concluding the study, Figuiero said during an interview: “Hopefully, how lighting is designed, manufactured, and applied in living and working environments will change in the near future.”7 She conceded, however, that further research needed to be performed and that this area of inquiry would benefit from further studies analyzing individuals’ interactions with manipulated light conducted over an extended period of time. This attests to the value of this data and analysis in informing the market at the intersection of light therapy and long-term care.

In 2016, the American Medical Association (AMA) produced a study in which it claimed that certain lights, such as “white” LED lamps, are physiologically impactful: they are at least five times more powerful in stimulating human retinas and inducing cognitive responses, due to their ability to powerfully suppress melatonin.8 The World Health Organization also supported this claim.9

Most recently, researchers in circadian biology, Jeffrey C. Hall, Michael Rosbash, and Michael W. Young, were awarded the Nobel Prize this year (2017) for having identified the specific gene behind circadian biology. This research proved that humans’ circadian clocks synchronize, or reset, to light by reducing levels of the protein PER. As a response, PER is high at night and low during the day. Further experiments, such as those conducted at Seghal Lab at Perelman School of Medicine, confirm that while the gear driving our circadian clocks is certainly the PER gene, the mechanism can still be “reset by light.”10 The ability for clocks to be “reset” ensures the entry-point for this study and the product, WALALIGHT® Light, which promises this effect.

Enter WALALIGHT® Light – Product Description and Process

WALALIGHT® Light provides a proprietary spectrum of light designed to optimize the functionality of an individual’s circadian rhythm.11 Its design is premised on light-related circadian rhythm processes12: “when humans are exposed to a light stimulus in the late biological day/early biological night, that stimulus produces a phase delay shift (a shift to a later hour), and light stimuli presented in the late biological night/early biological day produce phase advance shifts.”13

It achieves this by adjusting the levels of bio-active blue light, the spectrum by which human retinas are most stimulated.14 It adjusts for time in the day-night cycle, season, and latitude and longitude.15 These unique abilities primarily distinguish it among competitors.

Fiscal rationale: Improved Staff Retention

Use of WALALIGHT® Light as a non-pharmacological aid could potentially ease burdens on long-term care health-workers (CNAs, RNs, etc.) by improving patient capacity (risk of falling etc.) as well as irritability and combativeness towards nursing staff. These positions currently experience very high turnover rates because of their extreme level of demands. In some facilities, one year is at the longer end of the spectrum.16

According to Long-Term Care Nurse Staffing Study (2016)17:

PositionMean turnover rate
Direct resident care/bedside RN75.2%
Administrative RN47.6%
Direct resident care LVN69.1%
Administrative LVN35.3%

Direct/bedside resident care RNs clearly had the highest turnover rate in 2016. Furthermore, data from 2016

National Healthcare Retention and RN Staffing Report indicates that the average cost of turnover for a bedside RN ranges from $37,700 to $58,400, which results in the average hospital suffering losses anywhere from $5.2 to $8.1 million.18 Moreover, each percent change in RN turnover costs/saves the average hospital $373,200.19

75% of long-term care nurses cited stress and overwork as primary reasons to leave, in a 2011 American Nurses Associations survey.20 By palpably diminishing stressors such as combative and high-risk patients through improved sleep mechanisms, the fiscal benefits of this mechanism in terms of staff retention are perceivably high.

Research Methods

Use the survey data collected by bedside RNs on 39 patients to discern the health and financial merits of WALALIGHT® Light. The survey rates, on a scale of 1-10, the following symptoms: 1) Delusions/Hallucinations, 2) Agitations/Aggressions, 3) Depression, 4) Anxiety, 5) Apathy/Indifference, 6) Appetite, 7) Wandering, and 8) Sleep. A score of 10 indicates that the symptom was very severe, 1 indicates that the individual was barely exhibiting the symptom if at all. Missing data was excluded from analysis.

The survey was conducted thrice a week (Monday, Wednesday and Friday) over the course of 11 weeks, with data pre- and post-WALALIGHT® Light exposure. All analysis was done using excel.


Survey Data Analysis

The Y-axis is the score from 1-10 (1: lowest, 10: highest)

Weekly Average Scores of Categories

ADelusions/ hallucinations
BAgitations/ aggression
EApathy/ indifference


Conclusions and Recommendations

In early May, there seems to be pretty much no change between days, except for a slight decrease in average appetite on Wednesday. Overall, delusion/hallucinations had the highest score (~3.7) and depression had the lowest, closely followed by sleep. During the second week of data collection in May, appetite was also lower on Wednesday, but the scores very closely resemble week 1 of May. In late May (the week of the 26th), there is more variation day-to-day, and the trend suggests that on Thursday, the average appetite was much higher than earlier in the week. Anxiety with was higher early in the week (Tuesday) also declined and stayed low as the week progressed. Of all the scores, sleep and appetite had the highest peaks on Thursday.

In June, particularly the week of June 5, Thursday had the most noticeable difference with respect to an increase in appetite, a decrease in wandering, and an increase in sleep. On Thursday, there was a notable decline in the score for wandering for the rest of the week. The week of June 12th had missing data for Saturday and Sunday. On Thursday, there was a marked decline in apathy/indifference and anxiety but an increase in appetite and sleep.

During the week of July 10th, there was missing data. Wednesday seems to be an outlier in this half-week, with particularly lower scores for all of the categories. In mid-July, in the week of July 17th, Wednesday stood out for lower apathy, higher appetite, and higher sleep relative to the rest of the days. Friday had the highest number of wanderings. During the week of July 24th, it seems that every category increased in average score as the week progressed. Particularly, there was a drastic increase in sleep score between Monday and Tuesday. In the middle of the July 31st week, there was high fluctuation in the scoring. Between Tuesday and Friday, appetite and sleep increased and slightly decline after. Wandering went down but went up again, along with apathy and irritability

The graphs suggest that during the week of August 7th, there was not much change in scoring. There was a slight dip on Thursday for delusions/hallucinations. During the week of August 14th, last week of data collection, there was not much variability in scoring between each day. Overall, sleep got the highest score, and depression had the lowest.

It becomes clear that between May and August, the two factors with the greatest change were appetite and sleep; both of these categories had higher average scores in August compared to May, suggesting that exposure to Circadian Lighting® is associated with more sleep and better appetite. There was also an overall decline in delusions/hallucinations, agitations/aggressions, and irritability. A less pronounced decline was also noted in depression and anxiety. The average score for wandering increased very slightly by the end, and apathy/indifference increased as well. T-statistics to test for a difference between first and last week for each category were calculated. No statistically significant differences were noted.

There were various subjects that had missing data, and some subjects who were lost to follow up. It would be beneficial to try to understand what happened in these cases. This study should be expanded to increase sample size and explore multiple sites. Additionally, it would be interesting to see if there is an interaction between age and the effect of circadian lighting. It is possible that milder cases or earlier stages of disease can be more influenced by lighting, whereas older people who have been diagnosed for a long time will not be affected by lighting. It would be useful to explore such confounders to understand the true potential of influence of circadian lighting.

In conclusion, WalaLight Lighting® is a recommended product for long-term care. Sleep disturbances are pervasive among this demographic as are issues of agitated behavior which in turn, is identified as a course of low staff retention. As evidenced in this study, the particular efficacy of WalaLight Lighting® as a viable mechanism for improving sleep and reducing agitations/aggressions indicate significant value in the market of long-term care in terms of both its health benefit as a non-pharmacological treatment for patients as well as a prudent cost-effective measure for these facilities.


We would like to thank the Professor John Whitman for allowing us to analyze this data, and for his guidance along the way. We would also like to acknowledge Ms. Dania West who will be proving her insight from an administrative perspective.

1 Hanford, Nicholas, and Mariana Figueiro. “Light Therapy and Alzheimer’s Disease and Related Dementia: Past, Present, and Future.” Journal of Alzheimer’s Disease: JAD 33, no. 4 (January 1, 2013): 913–22.
2 Ibid.
3 Hanford, Nicholas, and Mariana Figueiro. “Light Therapy and Alzheimer’s Disease and Related Dementia.”
4 American Medical Association. “Report of the Council on Science and Public Health,” 2016.
5 Joseph, Anjali. “Impact of Light on Outcomes in Healthcare Settings.” The Center for Health Design, 2006.
6 “Lighting Affects Dementia Patients’ Sleep.” Accessed November 21, 2017.
7 Ibid.
8 American Medical Association. “Report of the Council on Science and Public Health,” 2016.
9 Moore-Ede, Martin, and Doros Platika. “Health Risks of Light at Night: The Good, the Bad, and the Time of Day of Bioactive Blue Light,” 2016.
10 Walverton, Mark. “Living by the Clock: The Science of Chronobiology,” June 3, 2015.
11 “The Story of CIRCADIAN® Light.” Accessed November 28, 2017.
12 “Circadian Rhythms – National Institute of General Medical Sciences.” Accessed November 29, 2017.
13 Duffy, Jeanne F., and Charles A. Czeisler. “Effect of Light on Human Circadian Physiology.” Sleep Medicine Clinics 4, no. 2 (June 2009): 165–77.
14 Moore-Ede, Martin, and Doros Platika. “Health Risks of Light at Night: The Good, the Bad, and the Time of Day of Bioactive Blue Light,” 2016.
15 Ibid.
16 Penn Center for Rehabilitation and Care, September 18, 2017.
17 Texas Center for Nursing Workforce Studies. “Long Term Care Nurse Staffing Study: Vacancy and Turnover,” 2016.
18 Mukamel, Dana B., William D. Spector, Rhona Limcangco, Ying Wang, Zhanlian Feng, and Vincent Mor. “The Costs of Turnover in Nursing Homes.” Medical Care 47, no. 10 (October 2009): 1039–45.
19 Ibid.
20 “2011 ANA Health and Safety Survey.” Accessed December 6, 2017.