Parkinson’s disease developed twice as often in patients with regular nightmares. Anxious dreams may be a prodromal symptom of Parkinson’s disease in the absence of cognitive impairment and depression.
The occurrence of nightmares or disturbing dreams in older adults is linked to the onset of Parkinson’s disease, a new study suggests. His results are presented in The Lancet Discovery Science.
Participants who had disturbing dreams at the start of the study had twice the risk of developing Parkinson’s disease at the end of the follow-up period, which averaged 7.3 years. Regular disturbing dreams are associated with a more than threefold increase in the risk of the disease during the first five years of observation. Over the next 7 years of observation, the risk decreased.
Patients with Parkinson’s disease and frequent disturbing dreams at the time of diagnosis may be at higher risk of early decline in motor and cognitive function.
The study included 3,818 men aged 67 years and older who did not initially have Parkinson’s disease (December 2003–April 2011). Participants completed sleep quality assessments based on the Pittsburgh Sleep Questionnaire (PSQI) and the Anxious Dream Frequency Index.
Multivariable logistic regression was used to estimate the odds ratio (OR) of incident Parkinson’s disease according to the frequency of disturbing dreams, adjusting for potential confounders.
After a mean follow-up of 7.3 years, 91 (2.4%) cases of incident Parkinson’s disease were identified. Participants with frequent disturbing dreams at baseline had a twofold risk of developing Parkinson’s disease (OR 2.01).
The authors note that cross-sectional studies show an association of Parkinson’s disease with changes in dream phenomenology, including an increased frequency of disturbing dreams. This includes changes in the content of normal dreams, such as increased negative emotions, increased physical aggression, and the development of rapid eye movement sleep behavior disorder. People with Parkinson’s disease are about four times more likely than the general population to experience frequent nightmares.