50 million. That’s the number of people affected of dementia worldwide, according to the World Health Organization (WHO). This deterioration of cognitive functions, which mainly affects older people, affects Memoryreasoning, orientation, comprehension, calculation, learning ability, language and judgment.
In a study published in 2022 in the journal eClinicalMedicine and brought back into the spotlight in June 2024 at the 10th Congress of the European Academy of Neurology (EAN) in Helsinki, Finland, British researchers questioned the link between nightmarescognitive decline and the risk of dementia. The results of this work suggest that older people who frequently have nightmares may be more likely to be diagnosed with dementia later in life.
Does having nightmares regularly increase the risk of cognitive decline?
To conduct this research, the scientists examined data from 600 adult men and women aged 35 to 64, and 2,600 adults aged 79 and over, with no medical history, between 2002 and 2012. They followed the participants in the group aged 35 to 64 for nine years and those in the group aged 79 and over for five years.
They were then asked to complete a series of questionnaires, which included questions about the frequency of nightmares. The researchers then analyzed the data using statistical software to determine whether participants with a higher frequency of nightmares were more likely to experience cognitive decline and be diagnosed with dementia.
The result? People aged 35 to 64 who had nightmares every week were four times more likely to experience cognitive decline over the next decade, while those aged 79 and over were 2.2 times more likely to be diagnosed with dementia.We have demonstrated for the first time that nightmares may be linked to dementia risk and cognitive decline in healthy adults in the general population” assured Abidemi Otaiku, the author of this study, in a press release published in 2022.
Nightmares and cognitive decline: a phenomenon that affects men more
In the course of their research, the authors of the study also observed that “Nightmares were more associated with cognitive decline and dementia in men but were only weakly associated with cognitive decline and dementia in women“.
However, further research is needed to confirm the link between nightmare frequency and risk of cognitive disorders. “Although further work is needed to confirm these links, we believe that bad dreams could be a useful way to identify people at high risk of dementia and put in place strategies to slow the onset of the disease,” Abidemi Otaiku stressed in 2022.
Asked by Medscape Medical News In 2024, the researcher adds that further studies are also needed to determine whether treating nightmares could help slow cognitive decline and/or prevent dementia.
Sources :
- Distressing dreams, cognitive decline, and risk of dementia: A prospective study of three population-based cohorts – eClinicalMedicine – 21/09/22
- Frequent Nightmares Predict Cognitive Decline and Dementia, UK Study Shows – European Academy of Neurology (EAN) Press Release – 06/29/24
- Nightmares in Middle Age a Forerunner of Dementia? – Medscape Medical News – 14/07/24
- Nightmares in middle age linked to dementia risk – University of Birmingham press release – 21/09/22
- Dementia – World Health Organization (WHO)
