Trouble Concentrating is an Easily Overlooked Symptom of Orthostatic Hypotension in Early Parkinson's Disease

Background: Trouble concentrating during orthostasis is one symptom of orthostatic hypotension (OH), but it is often ignored in clinical practice because OH incorporates many nonspecific symptoms. Blunted cognition during orthostasis may affect various aspects of the clinical status of patients with Parkinson's disease (PD), but its impact on drug-naïve, early PD patients is not clear. Objective: This study investigated the association between trouble concentrating during orthostasis and orthostatic blood pressure changes and the influence of trouble concentrating during orthostasis on other non-motor symptoms and health-related quality of life in de novo PD. Methods: A total of 124 patients with early PD were enrolled and received a structured clinical interview, physical examination, and validated questionnaires to evaluate motor and non-motor symptoms and quality of life. Disturbed concentration was evaluated with question 5 of the Orthostatic Hypotension Questionnaire system assessment (part I). Supine blood pressure and blood pressure change during tilt table testing were recorded, and any association was analyzed. Results: Among the study population, 76 (61.3%) patients had trouble concentrating. Patients with blunted concentration had a steeper decrease in blood pressure during orthostasis. The score for trouble concentrating was positively associated with non-motor symptoms and quality of life scores. Conclusions: Trouble concentrating when standing was a frequent finding in early, drug-naïve PD patients. It was positively associated with non-motor burden, mood and quality of life in patients with PD. OH was correlated with the incidence of trouble concentrating. Such findings complicate treatment but provide valuable information for managing early PD.