A recent study has linked a mysterious sleep disorder to an increased risk of cognitive decline in later life.
The study revealed that iRBD sleep-disorder, which manifests as the sleeper performing violent acts such as shouting, kicking and punching during sleep, may be an early indicator of cognitive decline and an increased risk of developing dementia in the future.
Intraocular sleep behavior disorder (iRBD) affects approximately 2% of older adults, causing them to lose the normal muscle paralysis associated with REM (rapid eye movement) sleep. During this stage, characterized by increased brain activity and rapid eye movement, the individual begins to act out their dreams physically, which may lead to shouting or laughing in their sleep, violent movements, or jumping out of bed and unintentionally injuring a bed partner.
The recent study included 162 patients in South Korea with an average age of 66 years, and monitored the development of their cognitive conditions over seven years by assessing 320 neurological and psychological indicators.
The results revealed a gradual decline in several cognitive functions among the participants, with a marked decrease in information processing speed, attention span, and working memory, as well as deterioration in both verbal and visual memory. Interestingly, this decline persisted even in patients whose condition did not progress to severe neurological diseases such as dementia or Parkinson's during the follow-up period.
The study also highlighted a key difference between the sexes, as the rate of cognitive decline in women with the disorder was much slower than in men, indicating a greater ability to withstand brain changes.
The researchers recommended developing monitoring and follow-up mechanisms that are appropriate to the sexual characteristics of patients, calling for further research to understand the biological basis behind these differences.
