Dreams are normal occurrences for everyone and most people report having them occasional nightmares. However, the frequency of your nightmares, and how old you are when you experience them, could reveal information about your risk of dementia.

Research shows that frequently experiencing disturbing dreams and nightmares ― meaning, in particular, frightening dreams that wake you up ― may be linked to a higher risk of cognitive decline and dementia.

An analysis from 2023 in American Journal of Preventive Medicine concluded that sleep disturbances should be considered when assessing a person at risk for dementia. Previous research has found a possible link between disturbing dreams and a higher risk of dementia in people with Parkinson’s disease. And a 2022 study published in The Lancet’s eClinicalMedicine found that some associations may also exist in the general population.

The 2022 study, by Dr Abidemi Otaiku, a clinical research fellow at Imperial College London, assessed 605 middle-aged adults at a cognitively normal baseline over a period of up to 13 years. The researchers also examined 2,600 older adults, with an average age of 83, at a dementia-free baseline for up to seven years.

The data suggested that the group of middle-aged adults who reported a higher frequency of nightmares – categorized as once a week or more – were associated with a higher risk of cognitive decline. Also, for older adults, the study found that more nightmares were linked to higher risks of “dementia of any cause” which means that the syndrome can be caused by a number of different diseases.

Middle-aged adults who reported having weekly nightmares, compared to those who reported having none, were 4 times more likely to be at risk of experiencing cognitive decline. Older adults with frequent painful dreams were about twice as likely to be at risk of dementia.

The cognitive function of the middle-aged participants was determined using five cognitive tests. Older participants were assessed for dementia by a physician.

But there were some limitations to the study, such as a lack of racial diversity among the participants, who were mostly white, and a possible underestimation of associations between nightmares and dementia among female participants. The associations between the findings between disturbing dreams and the risks of cognitive decline and dementia were significant only among men who were assessed, not among women.

Furthermore, the questionnaire given to the participants did not clearly distinguish between “bad dreams” and “nightmares”, which could have affected the responses. “Bad dreams” don’t wake you up, while nightmares can jolt you out of your sleep.

In a published article On The Conversation, Otaiku wrote that the study results could lead to two theories: one, that frequent nightmares may be one of the first signs of dementia, especially in men; and two, that regular nightmares could be a cause of dementia itself.

“Given the nature of this study, it is not possible to be sure which of these theories is correct (although I suspect it is the former),” Otaiku wrote. He added that the research could, however, provide new opportunities for earlier diagnoses and “possibly earlier interventions.”

More than 55 million people around the world have dementia. With so much going on conversations about sleep health and dementia diagnosesit’s important to stay up to date with any new information about early detection and things you can do to reduce your risk.

Research has shown that regular exercise and physical activity, staying socialand abstaining from smoking are among the ways you can reduce your risk of dementia.

Dr. Zaldy Tan, director of Memory and Healthy Aging Program at Cedars-Sinai, previously said HuffPost that a key tip for improving brain health is to avoid social isolation.

“As social beings, the human brain thrives on interacting with others… When this doesn’t happen, our memory and cognition can decline over time,” Tan said. “It’s important to stay engaged and connected with others.”

Adequate sleep it is also key to reducing risk. However, this can be a challenge if you are someone who has nightmares or bad dreams.

If you find that you have frequent disturbing dreams or nightmares, talk to your doctor about your symptoms. No tests are routinely done to diagnose a nightmare disorderwhich is a pattern of recurring frightening dreams that cause significant distress. But your doctor can explore whether other conditions or factors are contributing to nightmares.

Conformable Sleep Foundation People can also seek different types of therapeutic treatment, such as psychotherapy, that can address nightmares.