Tunable White Light for Elders (TWLITE): A Protocol Demonstrating Feasibility and Acceptability for Deployment, Remote Data Collection, and Analysis of a Home-Based Lighting Intervention in Older Adults

Abstract

Sleep disturbances are common in older adults and may contribute to disease progression in certain populations (e.g., Alzheimer’s disease). Light therapy is a simple and cost-effective intervention to improve sleep. Primary barriers to light therapy are: (1) poor acceptability of the use of devices, and (2) inflexibility of current devices to deliver beyond a fixed light spectrum and throughout the entirety of the day. However, dynamic, tunable lighting integrated into the native home lighting system can potentially overcome these limitations. Herein, we describe our protocol to implement a whole-home tunable lighting system installed throughout the homes of healthy older adults already enrolled in an existing study with embedded home assessment platforms (Oregon Center for Aging & Technology—ORCATECH). Within ORCATECH, continuous data on room location, activity, sleep, and general health parameters are collected at a minute-to-minute resolution over years of participation. This single-arm longitudinal protocol collected participants’ light usage in addition to ORCATECH outcome measures over a several month period before and after light installation. The protocol was implemented with four subjects living in three ORCATECH homes. Technical/usability challenges and feasibility/acceptability outcomes were explored. The successful implementation of our protocol supports the feasibility of implementing and integrating tunable whole-home lighting systems into an automated home-based assessment platform for continuous data collection of outcome variables, including long-term sleep measures. Challenges and iterative approaches are discussed. This protocol will inform the implementation of future clinical intervention trials using light therapy in patients at risk for developing Alzheimer’s disease and related conditions.

Remote Spectral Light Sensing in the Home Environment: Further Development of the TWLITE Study Concept

“…The present study is an extension of the previous Tunable White LIghT for Elders (TWLITE) study [14]. In TWLITE, participants homes were retrofitted with a tunable lighting system that was remotely controlled, such that all emitted light mirrored their natural environment according to time of day.…”

“…Pressure-sensitive bed mats placed under the mattress (EmFit Corp., San Marcos, TX, USA) were used to record information about the patterns of study participants time in bed. These bed mats were previously validated against wrist-based actigraphy [11,15] as well as the PIR motion sensor network [14] to identify sleep; however, henceforth, "time in bed" will be retained as the primary bed mat-related outcome. Figure 2 shows the nightly time in bed for three representative study participants as measured using the EmFit bed mats.…”

“…Figure 5 illustrates the total daily irradiance in three colors for the same study participant over the entire twelve weeks of the study. These values were obtained using the same approach combining motion sensor firings and light sensor values previously described for white light [14]. An example of combining these two data sets to estimate the in-home light exposure for an individual living alone is shown in Figure 5.…”

Effect of Indoor Wall Wood Coverage on the Elderly Group—A Case Study of Activity Rooms in Old-Age Buildings

“…St-Jean et al found that the utilization of blue-rich light enables older individuals to engage in more activities, despite the common perception that blue light diminishes work efficiency [10]. Furthermore, research has expanded to encompass more specific indicators of indoor lighting, such as illumination [11][12][13][14], color temperature [15][16][17], and light source location [18]. Research studies have shown that while illumination has minimal impact on the physiological rhythms of the elderly, it significantly influences their psychological state.…”