Characterization of de novo Dementia with Lewy Body with different duration of rapid eye movement sleep behavior disorder

•DLB patients with RBD were more likely to develop parkinsonian traits and autonomic dysfuction.•Autonomic dysfunction was more common in DLB patients with RBD when compared with DLB patients without RBD.•Significant symptom and phenotype variability existed between DLB patients with and without RBD, and also different RBD durations had significant effects on symptomatic disease phenotypes.