Wednesday, March 5, 2008

Bright Light Therapy aids sleeping disorders in Alzheimer's Disease

Alzheimer's disease is a progressive disease of the brain that causes dementia, gradually destroying a person's memory and ability to learn, reason, make judgements, communicate and carry out normal daily activities. Alzheimer's disease is the most common cause of dementia, particularly in older adults and accounting for about 60% of all cases. Most cases of Alzheimer's develop in those aged 65 or over. Below the age of 65, Alzheimer's is rare, affecting about 1 person in 1000. Over the age of 65 it affects about 1 in 20. The risk of developing Alzheimer's continues to increase with age, so those aged 80 have a higher risk of developing it than those aged 65. By the age of 85 nearly 1 in 2 will have the disease. Women have a slightly greater chance of developing Alzheimer's than men. It is thought that about 500,000 people in the UK are believed to have the disease. There is no known cure for Alzheimer's disease and very few effective treatments are available.

The symptoms of Alzheimer's disease can vary greatly, but those with the disease often have one or more of the following: 1. Problem with memory 2. Problems with speech and language 3. Confusion 4. Changes in mood and behaviour 5. Problem learning new information, ideas or skills 6. Difficulty performing simple everyday tasks

People afflicted with Alzheimer's often suffer disturbances in circadian (daily) rhythm, which affects body functions such as sleep cycles, temperature, alertness and hormone production. As a result, impaired sleep and nocturnal restlessness place great burdens on the sufferer and the care giver. Sedatives are usually prescribed; however these have limited usefulness and are typically accompanied by side effects.

It is thought that daily exposure of Alzheimer's patients to bright light may resolve circadian rhythm sleep disorders. According to the Sleep Review, clinical research has shown that exposure to very bright light in the day and darkness at night can consolidate rest and activity patterns in patients suffering from Alzheimer's disease. In a 12-week trial involving 27 women and 5 men aged 60-95 years, 15 subjects received 1 hour of exposure to bright natural light each morning and 17 control subjects were exposed only to normal low-light conditions. Results obtained from this trial indicated a trend toward increased sleep efficiency (percentage of time in bed spent asleep), decreased nighttime wakefulness, and decreased nighttime activity in the intervention group, compared with the controls.

Although further research needs to be done in this area, existing research have produced very promising results, which is a real light at the end of the tunnel for Alzheimer's Disease sufferers, caregivers and family members caring for such patients.

Useful links Alzheimer's Society

NHS Direct - Alzheimer's disease

Family Practice News Article - Light Therapy Aids Alzheimer's Sleep Disorders Sleep Review - Light Therapy and Alzheimer's disease