Do dreams tell the future? Dream content as a predictor of cognitive deterioration in Parkinson’s disease
Journal of Sleep Research August 9, 2020 P. Bugalho, F. Ladeira, Raquel Barbosa et al.
In Parkinson’s disease, negative emotions in dreams predict cognitive decline over four years. Among 58 non-demented patients, 23 reported dreams at baseline; aggression and negatively toned content predominated. Montreal Cognitive Assessment scores decreased significantly from baseline to follow-up. Negative emotion index in dreams was the strongest predictor of cognitive decline in a multivariate model, independent of motor stage, mood disorder, psychosis, or REM sleep behavior disorder. The findings suggest dream content may serve as an early marker of cognitive deterioration in Parkinson’s disease.