“DASH” symptoms in patients with Parkinson’s disease: Red flags for early cognitive decline

Neuropsychiatric features in Parkinson’s Disease (PD) are associated with developing dementia longitudinally. Therefore, identifying appropriate screening methods for such features, and their association with early cognitive dysfunction, may help to inform early intervention approaches. In this study, 53 PD patients without dementia underwent detailed neurological and neuropsychological assessment. The sum scores of the four items detailing Depression, Anxiety, Sleep disturbance and Hallucinosis (DASH) were calculated from the Parkinson’s Disease Questionnaire (PDQ-39) and examined in relation to cognitive tasks. Results demonstrated that higher DASH scores were significantly correlated with poorer working memory and set-shifting performance, even after controlling for age, predicted intellect, depression, disease stage and duration. These data indicate that DASH symptoms are related to executive dysfunction even in non-demented patients with PD. The DASH score may represent a simple screening method for highlighting early cognitive decline, which in turn is associated with the development of dementia in PD.