Feasibility Study on the Impact of Home Lighting on Visual Performance and Quality of Life for Older Adults With Low Vision

BACKGROUND: Low vision affects more than 5.5 million older adults in the United States, affecting daily activities, social functioning, and overall quality of life. This number is expected to double over the next decade. Occupational therapy efforts to improve visual performance for those with low vision include increasing magnification, size (text or symbols), and lighting levels. Lighting in the home is a low-cost means of improving visual function but seemingly underused. Although occupational therapists regularly perform home assessments to promote safety and independence, elements of home lighting may not be addressed in traditional assessments. In fact, older adults tend to have lower levels of illumination in their homes than recommended by lighting experts.

Recent assessments for home lighting include the Home Evaluation of Lighting Assessment (HELA; Perlmutter et al., 2013) and the LuxIQ (Jasper Ridge, 2018). The LuxIQ is an instrument that provides a range of lighting filters that enable individuals to identify their preferred lighting intensity and color. Limited research has evaluated the impact of optimum lighting levels on functional performance and quality of life.

PURPOSE: The purpose of this study was to examine the feasibility of conducting a study on the effects of home lighting on visual functioning, performance of close visual activities, and quality of life for older adults with low vision. The research questions were (1) Does optimized lighting in the home affect visual activities and quality of life for older adults with low vision? and (2) What is the feasibility of conducting a large study on home lighting for older adults living independently? The feasibility study was conducted to determine whether the intervention, demand, logistics, and assessments would be practical for a larger study.

METHOD: The study had a quasi-experimental design and used a convenience sample of older adults with low vision. Inclusion criteria were having visual acuity between 20/40 and 20/400, being cognitively intact, and living independently. Participants were recruited through phone calls to residents in a local senior living community. Participants underwent visual screens including the Colenbrander, Warren Text Card, MNRead, and the Low Vision Quality-of-Life Questionnaire (LVQOL; Wolffsohn & Cochrane, 2000). Home lighting was evaluated using the HELA and light meter.

The Lux IQ identified optimum lighting levels for each participant’s chosen room. Participants chose a task light that was adjusted to the optimal level of illumination for one reading area and received a home lighting report with recommendations for optimizing lighting. Participants retook the MNRead, portions of the HELA, and the LVQOL to determine whether improved lighting influenced visual functioning, quality of life, and the ability to perform close functional tasks.

Descriptive statistics were conducted using IBM SPSS Statistics Version 23 (IBM Corp., Armonk, NY) to describe the sample and summarize changes in MNRead and LVQOL scores. Feasibility was examined according to the following domains: acceptability, demand, implementation, practicality, adaptation, expansion, and efficacy.

RESULTS: Nine older adults with a mean age of 83 (range = 76–97) participated. They had mostly minimal (<20/40) or severe (<20/200 to <20/400) vision loss. One participant was excluded because of visual acuity of >20/400. All participants were satisfied with the process (acceptability) and noted the need for the study (demand). Six participants received task lighting and/or light bulbs in locations where they performed near task activities. Task lamps increased the average lighting level by 812 lux and participants’ reading ability levels on the MNRead by two lines (efficacy). On the LVQOL, two participants showed no functional change, four increased functional performance (efficacy), and two were not using task lights at follow-up calls because of problems with glare or design of the lamp (implementation, practicality). The cost of the task lights averaged $30 (range = $15–$60); approximately 90 minutes was spent with each participant.

CONCLUSION: The study is feasible to conduct with modifications considered regarding practicality (types of task lamps), the need for onsite follow-up (implementation), and the utility of the assessment.

IMPACT STATEMENT: Task lighting is a cost-efficient means to improve older adults’ visual function and quality of life for performance in near task activities. Follow-up in older adults’ homes is necessary to ensure practicality of use.

References

Bowers, A., Meek, C., & Stewart, N. (2001). Illumination and reading performance in age-related macular degeneration. Clinical and Experimental Optometry, 84, 139–147. https://doi.org/10.1111/j.1444-0938.2001.tb04957.x

Brunnström, G., Sörenson, S., Alsterstad, K., & Sjöstrand, J. (2004). Quality of light and quality of life—The effect of lighting adaptation among people with low vision. Ophthalmic and Physiological Optometry, 24, 274–280. https://doi.org/10.1111/j.1475-1313.2004.00192.x

Jasper Ridge. (2018). LuxIQ/2 tint and lighting exam system. Available from http://jasperridge.net/

Perlmutter, M. S., Bhorade, A., Gordon, M., Hollingsworth, H., Engsberg, J. E., & Baum, M. C. (2013). Home lighting assessment for clients with low vision. American Journal of Occupational Therapy, 67, 674–682. http://dx.doi.org/10.5014/ajot.2013.006692

Wolffsohn, J. S., & Cochrane, A. L. (2000). Design of the Low Vision Quality-of-Life Questionnaire (LVQOL) and measuring the outcome of low-vision rehabilitation. American Journal of Ophthalmology, 130, 793–802. https://doi.org/10.1016/S0002-9394(00)00610-3