Circadian Rhythm Lighting and Sundowners Syndrome

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It was one of the first times I had been in a Memory Care Residence installing our Walalight Circadian Rhythm Lighting System and that is what it sounded like. The smack was Joe’s hand hitting the side of my head. “Ouch” was me responding to Joe’s hand hitting the side of my head and “Its ok Joe” was me responding and trying to reassure Joe to help him get through an episode of Sundowners Syndrome, also known as Sundowning.

Sundowning is a descriptive term, not a psychiatric diagnosis. The term is broadly used to describe a set of symptoms ocurring in elderly patients who may or may not be suffering from Dementia. These episodes include a wide variety of symptoms such as wandering, agitation, agression and confusion. Some of these behaviors are present in general Dementia, Delirium, Parkinsons, or sleep disturbance and may not be specific to Sundowners.

However, the unique difference between disruptive behaviors associated with general Dementia, and Sundowners is that Sundowners usually manifests in the late afternoon or early evening. Behavior associated with Sundowners can be very difficult for caretakers to deal with. One study shows that many Dementia patients with Sundowners end up being institutionalized. It is believed that disruptions to our Circadian Rhythms could be a major factor in the onset of Sundowners Syndrome.

The key components of the human Circadian Rhythm are the Suprachiasmatic Nucleus (SCN) and Melatonin. The SCN is in the Hypothalmus of the brain and regulates the sleep wake cycle by producing an awake signal during the day and a sleep signal at night. The SCN influences core physiological functions including temperature, heart rate and and hormone secretion. Specifically, the SCN regulates the production of the hormone Melatonin, which is key to our sleep wake cycle.

Disruption of the circadian rhythms due to deterioration of the SCN observed in patients with Advanced Dementia (AD) may contribute to the development of Sundowning Syndrome. The possible cause of the SCN deterioration is due to senile plaque formation that increases with age. These pathological changes may theoretically explain disturbed sleep, agitation, confusion, and other symptoms of sundowning. It is suggested that the volume of SCN, as well as its cell number decreases in persons between the ages of 80 and 100 years. Patients with dementia of the Alzheimer’s type have more prominent abnormalities in SCN.6  

Although it is not known exactly what causes Sundowners episodes, one thought relates to a persons programmed life routine which generally had a purpose. For most people the late afternoon/early evening represents a time of day when there is clear purpose and routine. Work is ending and we get to go home and see our families, head to a favorite activity, or just kick our feet up and relax. It is possible that the absence of this purpose at the end of the day can bring on confusion and anxiety which leads to frustration and aggression. 

During a recent visit to a Memory Care residence I was told about an experiment they tried. They had a resident who was experiencing regular Sundowner episodes around 5:00 pm. This resident had been a high-level CPA and worked feverishly for his entire life. The resident’s actual desk, computer, chair, coffee mug and telephone were brought in and set up in a small office inside the residence. They even included a copy of his regular newspaper on the desk. The resident was brought into the office after lunch for a few hours. Although he did not necessarily recognize any specific item, he engaged with them and asked questions. He stared at the newspaper and after a few minutes stated that it was time to go home.

Although this was an isolated experiment which did not last very long, the unofficial results were telling. The quantity and intensity of episodes was reduced for a few days, the resident slept better, and the overall demeanor of the resident appeared to be positively impacted.

While there is no cure for Sundowners, there are many things that can be done to minimize the adverse effects on residents and caregivers:

  1. Encourage activities early in the day including exposure to sunlight and avoid stimulants like cafeine.
  2. Set good sleep habits, use a nightlight to reduce anxiety, and consider Melatonin supplements.
  3. Provide a calm environment in the evening by reducing sensory stimulation, minimizing clutter, and regulating temperature.
  4. Reassure and reduce anxiety. Validate their feelings even if it makes no sense, Reassure and Distract. 
  5. Ensure that residents are being exposed to sufficient healthy blue light during the day and healthy non blue lighting in the evening.

Given the importance of proper daytime and nightime lighting, it is no surprise that Memory Care residents are suffering due to the lack of proper lighting. They are living in biological darkness 24 hours a day and it is wreaking havoc on their health and the health of their caretakers.

According to CEO Harry Zuker, Walalight Circadian Rhythm Lighting Systems are designed to correct this natural light deficit challenge by providing the proper blue rich light spectrum during the day as well as the proper blue deleted spectrum for nighttime. “Walalight uses an advanced PCB chipset manufactured by Seoul Semiconductor” says Zuker.” This chipset, along with proprietary technology, produces a light spectrum most closely resembling the suns actual spectrum.” 

The fully automated, low-cost system is simple to understand, simple to buy, simple to install and simple to use and should be considered for any environment where natural light is restricted.


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