A little known sleep disorder that affects two per cent of people over 65 could foreshadow the likeliness of developing brain diseases such as Parkinson’s disease and dementia.
The disorder known as REM sleep behaviour disorder, or RBD, affects around one per cent of the general population.
REM stands for rapid eye movement which is one of the stages of the sleep cycle. It plays an important role in dreaming, memory, emotional processing, and healthy brain development.
During this stage you enter a state of low muscle tone throughout the body meaning your muscles don't 'act out' your dreams.
But with REM sleep behaviour disorder, sufferers respond to their dreams, shouting, screaming and even kicking.
Patients report being chased or attacked in their dreams and can respond violently.
It can lead to them harming themselves or even harm a partner. Some 60 per cent of patients and 20 per cent of bed partners of people with the disorder have reported injuries during sleep.
The disorder is not fully understood. It can appear at any age but usually starts for people in their 40s and 50s.
For those younger, antidepressants can cause the disorder.
Younger women and men are affected in equal numbers but over 50 it tends to affect men more often.
It has been associated with neurodegenerative disorders such as Parkinson’s disease and dementia with Lewy bodies.
Scientists are trying to work out if REM sleep behaviour disorder may foreshadow these horrible diseases.
It is seen in 25 to 58 per cent of patients diagnosed with Parkinson’s and 70 to 80 per cent of patients with dementia with Lewy bodies.
In a long-term study looking at 1,280 patients with the disorder, researchers observed participants to see how other issues developed.
After 12 years, 73.5 per cent of those with REM sleep behaviour disorder had developed a related neurodegenerative illness.
Other things that were shown to increase the risk of developing a neurodegenerative disorder were irregular motor symptoms, abnormal dopamine levels, loss of sense of smell, cognitive impairment, abnormal colour vision, erectile dysfunction, constipation and older age, reports OregonLive.
RBD may be detectable decades before the symptoms fully develop and early detection would help boffins study the disease.
But at this time there are few therapies in way of treatment but melatonin and clonazepam can be used as medicine to improve the symptoms.
