Nightmares can be unsettling for anyone, but new research from Britain suggests that bad dreams may signal the start of Parkinson's disease in some older adults.
"Although it can be really beneficial to diagnose Parkinson's disease early, there are very few risk indicators and many of these require expensive hospital tests or are very common and nonspecific, such as diabetes," explained study author Abidemi Otaiku, from the University of Birmingham's Centre for Human Brain Health.
"While we need to carry out further research in this area, identifying the significance of bad dreams and nightmares could indicate that individuals who experience changes to their dreams in older age -- without any obvious trigger -- should seek medical advice," Otaiku said in a university news release.
In the study, Otaiku's team analyzed data from more than 3,800 older men in the United States who took part in a 12-year study. At the start of that study, the men provided a wide range of information, including details about their sleep.
MDMA improves post-traumatic stress disorder symptoms, study finds