The Era of Circadian Lighting is Here
07-28-20 Courtesy of Philadelphia Inquirer
The Medical Behavioral Unit at Children’s Hospital of Philadelphia (CHOP) was an unusual concept from the start. The first of its kind in the nation, it would be a special place for kids with medical problems who also had underlying behavioral conditions such as depression, anxiety, and autism.
Although there’s no doubt that this is a hospital, the obvious decorative features of the unit — the subtle but cheery colors, the stylized nature art — are soft and soothing, neither depressing nor overly stimulating.
What’s not so obvious is the lighting. The design includes what is quickly becoming standard practice in health-care settings and, to a lesser degree so far, schools, high-tech workplaces, and warehouses.
Image by Ida York Design
The idea is to tune indoor lights to mimic the brightness and color spectrum of the sun as it changes during the day. Think bright, bluish light in the morning that gradually grows more amber at dusk and ultimately gets as dark as is possible to get in a medical environment. There’s growing evidence that proper light exposure can help keep our circadian rhythms —the body’s internal, 24-hour clock — in sync with the sun. That can improve sleep, mood, and metabolic function. It’s particularly important in hospitals and nursing facilities, where illness, long exposure to dim artificial light, and frequent wakening at night can cause disrupted sleep and behavior problems. The benefits in schools and offices are numerous as well.
Although the color tone of the light changes, it does not look obviously blue, yellow, or red. What is noticeable is that it is gentler and more pleasant than much office lighting.
A well-functioning circadian rhythm is associated with better immune functioning and sleep, plus lower stress. When their circadian systems are out of whack, people are at higher risk for diabetes, obesity, cancer, and mood disorders. Patients hospitalized for more than two or three days can run into trouble because, without proper light exposure, biological clocks shift a few minutes each day. Hospitals and nursing homes typically have too little light during the day and too much at night.
Research with nursing home residents with Alzheimer’s and other dementias has found that exposure to bright light in the morning improved scores on measures of sleep quality, behavior, and mood. One study that tried circadian lighting with dementia patients living at home found that caregivers also slept better.
Kate Wickham, vice president of connected indoor lighting systems for Signify, said her company has seen “huge interest” in the last 18 months to two years in healthcare . Signify, she said, is also talking with people who operate office space, warehouses, and hotels.
“I love the fact that it’s something that can promote a healing environment that is noninvasive,” Wickham said.
Stephanie Doupnik, a pediatrician who is the unit’s co-medical director, said she doesn’t miss natural sunlight as much as when she worked in other places. “I don’t think I’ve ever heard a complaint about the lighting,” she said. “I think that’s actually a remarkable thing.”