Lighting for the elderly

Older people also have reduced levels of retinal illuminance, such as having smaller pupils and less transparent crystalline lenses.

Furthermore, as an individual ages, they begins to lose retinal neurons, which not only compromises the ability to see but also to register a robust daily pattern of light-dark that is needed to maintain biological rhythms.

Low lighting levels may contribute to slips, trips and falls in the elderly by lowering visibility of hazards such as unexpected steps, or sudden changes in floor surfaces.

Obstacles to a safe passage may include clutter or ill-placed furniture, which can cause a slip or a trip.

Grab bars and stair rails are obvious aids but must be visible to the user, and so such environments demand strong lighting.

Falls of elderly people causes a significant number of hip joint fractures, replacement of which is a serious medical event.

Falls from ladders are very common among the elderly, especially men, with potentially worse injuries owing to the greater heights involved.

Thus, when switched on, lights should react instantaneously, so the user is not surprised by a hidden obstacle as they moves into a kitchen or bathroom, for example.

Higher lighting levels enable users to see potential hazards before they need to take avoiding action, and so negotiate them safely and easily.

Some skill is needed to meet the several criteria governing good lighting systems, especially for senior citizens and patients.

Impairment of these SCN-mediated circadian rhythms becomes increasingly common with advancing age, diminished health, and Alzheimer's disease, thereby contributing to the high prevalence of sleep disturbances in these populations.

[2] The elderly tend to go to bed early in the evening and wake earlier in the morning than younger adults.

[11] This is the first device created to accurately measure and characterize light (intensity, spectrum, timing, and duration) entering the eye that affects the human body's clock.

The device measures activity and light together at regular time intervals and electronically stores and logs its operating temperature.

The light, or the better sleep, also helped to reduce agitated behavior such as pacing, aggressiveness, and speaking loudly.

[26][27] Nightlights that accent horizontal and vertical spaces, such as soft lighting above a doorway or at the foot of a bed, can reduce the risk of falls without disturbing sleep.