It turns out that nightmares may do more than just interrupt a good night’s sleep. For middle-age people, frequent bad dreams can make them more likely to be diagnosed with dementia later in life.
That’s the main finding from a group of researchers in the United Kingdom, who explored the relationship between distressing dreams, cognitive decline and dementia risk in otherwise healthy adults. To do that, they analyzed about a decade of sleep data from more than 600 people between ages 35 and 64, as well as 2,600 others age 79 and older.
Middle-age people — defined as those ages 35 to 64 — who had nightmares at least once a week were four times more likely to have cognitive decline in the following decade than those who had less frequent bad dreams. Among the older study participants, those who experienced weekly or more frequent nightmares were twice as likely to be diagnosed with dementia.
Gender also appears to make a difference: Older men who had weekly nightmares were five times more likely to develop dementia than older men with no bad dreams. Among women, the increased risk was 41%.
Researchers say the gender and age findings are just a start. Next, they want to more fully understand whether nightmares in young people are a harbinger of future dementia risk. There are other factors to consider, including whether the intensity of bad dreams and the ability to remember them ultimately plays a role in the rise of dementia. There is also much to learn about the biological basis of bad dreams, which the researchers plan to explore.
Until science has more answers, establish good pre-sleep habits to make sure you’re counting sheep and not running from monsters.