Background: A limited number of studies examined anxiety in Parkinson disease (PD). Questionable validity of the Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) defined anxiety disorders in PD population as well as a lack of validated rating scales hampered the investigation in this field.
Objective: To screen for prevalence of anxiety symptoms and their associated demographic and clinical features in an outpatient-based cohort with PD.
Patients and methods: A consecutive series of 360 patients with PD underwent investigation with the Hamilton Anxiety Rating Scale (HARS), the 17-item Hamilton Depression Rating Scale, Neuropsychiatric Inventory, section E (anxiety), motor scoring with Hoehn and Yahr staging, the Unified Parkinson's Disease Rating Scale, and cognitive screening with the Mini-Mental State Examination.
Results: In all, 136 (37.8%) patients with PD of our cohort had anxiety symptoms, whereas both depression and anxiety were recorded in 5.6% of the patients, while in 56.7% neither anxiety nor depression was present. Female gender, motor disability, and core depression symptoms were the main markers of anxiety in patients with PD. The severity of anxiety symptoms was not associated with asymmetry of motor symptoms. Education, disease duration, and levodopa dose were poor predictors in the model. The HARS had a satisfactory inter-item correlation, convergent validity, and factorial structure.
Conclusions: Anxiety may be present as an isolated symptom, with specific demographic and clinical markers, and not only as a feature of depression in PD population. This highlighted the importance of identifying anxiety symptoms when treating patients with PD.