This study investigated the association between distressing dreams (bad dreams and nightmares) and the risk of premature mortality and accelerated biological ageing in community-dwelling adults.

Distressing dreams are associated with an increased risk of developing age-related neurodegenerative diseases. Whether distressing dreams increase the risk of developing other age-related health outcomes is unknown. 

This longitudinal, multi-cohort study used pooled data from three US cohort studies (Midlife in the United States [MIDUS]; The Wisconsin Sleep Cohort [WSC]; The Osteoporotic Fractures in Men Study [MrOS]). Distressing dream frequency was self-reported at baseline in all cohorts. Premature all-cause mortality (before age 75 years) was defined using study records (compiled from 2000-2024). Cox regression was used to analyse the prospective association between distressing dreams and premature mortality. In MIDUS, the pace of biological aging was measured at baseline using the DunedinPACE epigenetic clock. Mediation analysis was used to assess whether accelerated biological ageing mediates the relationship between distressing dreams and premature mortality.

Among a total population of 4,105 participants (mean age=60.3 years, age range=26-74), 335 (8.2%) experienced frequent distressing dreams at baseline. During 18.3 years of follow-up, 227 premature mortality cases were documented. After adjusting for demographic characteristics, frequent distressing dreams were associated with a nearly 3-fold risk of premature death in the pooled cohort (HR=2.57, P<0.001) and in each cohort separately (MIDUS: HR=2.74; WSC: HR=2.77; MrOS: HR=2.25; P’s<0.05). In MIDUS, individuals with frequent distressing dreams exhibited a faster pace of biological aging (P=0.009). Accelerated biological ageing mediated 21% of the distressing dream-mortality association. These associations remained robust when adjusting for a wide range of possible confounders.

Adults with frequent distressing dreams experience faster biological aging and die at younger ages. Future studies are needed to determine whether treating distressing dreams could slow biological ageing and reduce mortality risk in the general population.