People who experienced frequent nightmares in childhood are more likely to develop dementia and Parkinson’s disease later in life, according to a new study.
Researchers collected data from nearly 7,000 British residents over 50 years and learned that participants who had persistent bad dreams had an 85% increased risk of developing a cognitive impairment like dementia and Alzheimer’s, or Parkinson’s by age 50.
The study, published Sunday in The Lancet’s eClinicalMedicine journal, analyzed data from the 1958 British Birth Cohort Study — which collected info on all people born in Britain during a single week in March 1958 — including whether they had nightmares at ages 7 and 11.
Doctors then assessed the individuals’ cognitive abilities at age 50 — in 2008.
They found that 267 people — or 3.8% — within the study group who submitted to the assessment had developed a form of cognitive impairment or Parkinson’s Disease.
The children who had distressing dreams at ages 7 and 11 were 76% more likely to develop a cognitive impairment and were nearly seven times more likely to be diagnosed with Parkinson’s than those who had none, the study author said in his findings.
“The results were clear,” the author and clinical neurology fellow Abidemi Otaiku wrote in an article about his findings. “The more regularly the children experienced bad dreams, the more likely they were to develop cognitive impairment or be diagnosed with Parkinson’s disease.”
Otaiku noted, however, that more research needs to be done on the topic to determine if the link between nightmares and the health issues are causal.
One possible explanation between the connection could be heredity. A gene known to increase the risk of regular nightmares has also been linked to an increased risk of developing Alzheimer’s disease in old age, according to the researcher.
Another potential reason could be that frequent nightmares disrupt sleep, which is needed for humans to recharge and restore their brain energy, he said.
However if causation is proved by future studies, early treatment of nightmares could become a “primary prevention strategy” for both dementia and Parkinson’s, Otaiku said.
“Being aware that bad dreams in childhood may signal a higher risk of dementia or Parkinson’s later in life suggests that there could be a window of opportunity to implement simple strategies to lower those risks,” he wrote in the article.
Earlier studies have suggested that middle-aged and older adults who have frequent nightmares could be more than twice as likely to develop the two disorders in the future.