While the trend toward indoor and outdoor LED relamping projects has been exploding in recent years because of cost- and energy-saving saving opportunities, a less noticeable LED trend is expected to come into its own in the near future. That trend is the value of LED relamping as a way to improve physical and mental health.

A new scientific research study, published by the American Academy of Sleep Medicine, highlights the opportunities that exist in this area specifically as they relate to the elderly in nursing homes. According to Mariana Figueiro, Ph.D., a professor and director of the Lighting Research Center at Rensselaer Polytechnic Institute, people with Alzheimer's disease and related dementias may experience sleep problems, wandering and associated daytime irritability. The study found a tailored lighting intervention can positively affect sleep, mood and behavior for patients with Alzheimer's disease.

Results of the study were presented last week in Baltimore at the annual meeting of the Associated Professional Sleep Societies.

According to the study, light exposure during the day helps consolidate sleep and improve behavior in these patients, but the light levels required are high, and available lighting fixtures cannot deliver the level and spectrum of lighting that maximally affects the circadian rhythm.

"Here, we show that, if the stimulus [light dose] is carefully delivered and measured, it can have a strong impact on sleep, depression and agitation," Dr. Figueiro said.

In specific, compared to baseline and inactive lighting, the lighting intervention significantly decreased sleep disturbances, depression and agitation.

"Depression was a secondary measure, and I was pleasantly surprised by the positive impact of the light treatment on depression scores," she said.

Measures of sleep disturbance (using the Pittsburgh Sleep Quality Index), mood (using the Cornell Scale for Depression in Dementia) and agitation (using the Cohen-Mansfield Agitation Index) were collected prior to the light intervention and during the final week of the intervention.

The lighting intervention was added to spaces in the nursing home in which patients spent most of their waking hours and was energized from wake time until 6 p.m. The light sources used were LEDs.

"The active light delivered a circadian stimulus of 0.3, which was about 300 to 400 lux at the eye of a 5,000K light source, and the inactive was delivering a circadian stimulus of 0.1," Dr. Figueiro said. The latter equates to less than 50 lux at the eye of a 2,700K light.

 For more information on Dr. Figueiro's work at the Lighting Research Center, including information on how to design building lighting plans with health in mind, go to: http://www.lrc.rpi.edu/programs/lightHealth/index.asp