Dr Abidemi Otaiku
Frequent nightmares triple the risk of premature death in adults and accelerate biological ageing in both adults and children, a major first-of-its-kind study reveals.
Presented at the European Academy of Neurology (EAN) Congress 2025 in Helsinki, lead researcher Dr Abidemi Otaiku from the UK Dementia Research Institute and Imperial College London said the association of weekly nightmares was independent of traditional risk factors for ageing and mortality “and frighteningly” appeared to be a stronger predictor of premature death than smoking, obesity, poor diet and low physical activity.
Dr Otaiku and his team of investigators analysed data from 2,429 children aged 8-10 and 183,012 adults aged 26-86 across six long-term population cohorts.
Nightmare frequency in adults was self-reported using a questionnaire at the start of the study, with participants followed for up to 19 years. For children, nightmare frequency was reported by their parents.
Biological ageing in children was assessed by measuring the length of their telomeres – small DNA sequences that serve as indicators of cellular ageing – using saliva and blood samples. Biological ageing in adults was assessed using telomere length as well as three advanced epigenetic clocks.
Findings showed that adults who reported weekly nightmares were more than three times as likely to die before the age of 70 compared to those who occasionally or never experienced nightmares.
Children and adults with more frequent nightmares also exhibited faster biological ageing, which accounted for about 40% of the heightened mortality risk.
The association between nightmares and accelerated ageing was independent of other risk factors such as genetic factors, other sleep problems, psychological distress, and childhood adversity and lifetime trauma.
Dr Otaiku said the accelerated ageing finding might explain why nightmares in early life predicted neurodegenerative diseases such as dementia and Parkinson’s disease in later life, which had been demonstrated in other research.
He stressed that given how common nightmares were and their modifiability, they should be taken “far more seriously as a public health concern”.
“Our sleeping brains cannot distinguish dreams from reality,” he said.
“That’s why nightmares often wake us up sweating, gasping for breath, and with our hearts pounding – because our fight-or-flight response has been triggered. This stress reaction can be even more intense than anything we experience while awake.”
He continued: “Nightmares lead to prolonged elevations of cortisol, a stress hormone closely linked to faster cellular ageing. For those who frequently experience nightmares, this cumulative stress may significantly impact the ageing process. Additionally, nightmares disrupt both sleep quality and duration, impairing the body’s essential overnight cellular restoration and repair. The combined effects of chronic stress and disrupted sleep likely contribute to the accelerated ageing of our cells and bodies.”
The association between frequent nightmares and accelerated ageing remained consistent across all ages, sexes, ethnicities, and mental health statuses, indicating a universal effect. Further studies were needed to determine whether treating nightmares could slow biological ageing and reduce mortality risk.
“If further studies confirm the causal impact of nightmares on ageing and brain health, then preventing and treating them could become one of the simplest, most cost-effective strategies to slow ageing at a population level,” Dr Otaiku said.