Distressing dreams and risk of Parkinson's disease: A population-based cohort study.

Abstract

During a mean follow-up of 7·3 years, 91 (2·4%) cases of incident PD were identified. Participants with frequent distressing dreams at baseline had a 2-fold risk for incident PD (OR, 2·01; 95% CI, 1·1-3·6, P = 0.02). When stratified by follow-up time, frequent distressing dreams were associated with a greater than 3-fold risk for incident PD during the first 5 years after baseline (OR, 3·38; 95% CI, 1·3-8·7; P = 0·01), however no effect was found during the subsequent 7 years (OR, 1·55; 95% CI, 0·7-3·3; P = 0·26).