Older people who are sleepy during the day, or lack enthusiasm for participating in activities due to sleep problems, may be more likely to develop a syndrome that can lead to dementiaaccording to a study published in the online issue of the American Academy of Neurology’s medical journal Neurology.

The study involved 445 people with an average age of 76 who did not have dementia. Participants completed sleep questionnaires at the start of the study and were asked about memory issues. Their walking speed was tested on a treadmill at the start of the study and then once a year for an average of three years. At the start of the study, 42 people had Motor Cognitive Risk syndromea condition that can occur before the development of dementia. People with this syndrome have slow walking speed and memory problems, although they do not have motor disability or dementia.

Another 36 people developed the syndrome during the study. Of those with excessive daytime sleepiness and lack of enthusiasm, 35.5% developed the syndrome, compared to 6.7% of those without these problems.

The researchers adjusted for other factors that could affect the risk of developing the syndrome, such as age, depression and other health conditions, and found that people with excessive daytime sleepiness and lack of excitement were more than three times as likely to develop the syndrome than those who had no sleep-related problems.

“Our findings highlight the need to screen for sleep issues,” notes study author Victoire Leroy, from the Albert Einstein College of Medicine in New York.

However, the researchers clarify that the study does not prove that these sleep-related issues cause the syndrome, it only shows an association.

Also, a limitation of the study is that the participants self-reported their sleep information, so they may not have remembered everything accurately.