LIGHT AND HEALTH
BRIGHT DAYS AND By MARIANA G. FIGUEIRO AND DAVID PEDLER
Light and Health Research Center at Mount Sinai
20
promotes well-being and improves mood.
For the better part of 20 years, we at the Light and Health Research Center (LHRC) have explored non-pharmacological tailored lighting interventions (TLIs) for promoting synchrony between the human circadian system and the solar day. Achieving this synchrony has been proven to alleviate the ill effects of circadian disruption among populations as diverse as Alzheimer's disease patients, shift-working nurses, school children and US Navy submariners. Our last article in designing lighting reported on the use of light tables to help Alzheimer's disease patients sleep better. Here, we report on a pilot study designed to extend our research to people with Parkinson’s disease (PD) to determine whether a TLI would improve subjective and objective measures of nighttime sleep as measured by questionnaires and actigraphy. The secondary aim was to determine whether the TLI would improve measures of mood symptoms.
PD is the second most common neurodegenerative disorder (behind Alzheimer's disease) afflicting American adults, usually first appearing as a slowing of motor movement accompanied by tremor while resting and rigidity later in life. These and numerous other non-motor symptoms (loss of smell, mood disorders, sleep problems, cognitive changes, etc.) profoundly impact quality of life for patients and their caregivers. There is growing evidence that the disruption of circadian rhythms — that is, bodily functions/processes that repeat every 24 hours (on average) — may also play an underlying role in PD patients' disordered sleep,1 perhaps even contributing to the development of the disease.2
Our premise is simple math: brighter days + darker nights = better quality of life. Simply put, a robust light-dark pattern delivering bright days and dark nights will help synchronize the biological clock with the solar day and foster circadian entrainment that leads to better sleep. Better sleep, in turn,
Following specifications proven in our previous studies,3, 4 the TLI was carefully designed to provide a robust light–dark pattern to maximally stimulate the human circadian system based on the mathematical model of circadian stimulus (CS) developed by Rea and colleagues.5, 6 Our research has shown
designing lighting
The lighting intervention