Funded Studies
This grant builds upon the research from a prior grant: Comparitive gene expression analysis of the brain in Parkinson's Disease and in familial encephalopathy with neuroserpin inclusion bodies (FENIB): implications for pathogenesis
Promising Outcomes of Original Grant:
A previous MJFF sponsored study showed that the available anxiety questionnaires are not suitable to assess anxiety in Parkinson’s disease (PD). The different rating scales measure different aspects of anxiety, such as persistent anxiety or panic attacks, and none is specifically suited to rate anxiety related to motor states (‘off’- anxiety). Thus, the different rating scales do not capture the full spectrum of anxiety in patients with PD, and each identifies patients with different symptoms. In addition, some of the rating scales are more sensitive for depressive than for anxiety symptoms.
Objectives for Supplemental Investigation:
The main objective of this study is to design a new anxiety rating scale that fulfills clinometric requirements. Based on a number of statistical analyses, sensitive items that cover the full range and severity of anxiety symptoms will be selected out of the database from the previous study and included in the new scale. This new scale will then be validated in a new PD population.
Additional objectives of this follow-up study are to identify different presentations of anxiety in Parkinson’s disease and to evaluate the impact of anxiety on the course and prognosis of motor and non-motor symptoms. For this latter objective, a number of patients that participated in the previous study will be re-assessed.
Importance of This Research for the Development of a New PD Therapy:
The design of a new and clinometrically sound anxiety scale will prepare the way for reliable pharmacological treatment studies of anxiety in PD. Knowledge of the different presentations of anxiety is important in this respect since differential treatment approaches may be needed for different presentations. Finally, longitudinal assessment may reveal the impact of baseline anxiety on the long-term course of motor and non-motor symptoms.
Final Outcome
A new anxiety rating scale was designed, called the 'Parkinson Anxiety Scale (PAS). This scale is a 12-item observer or patient-rated scale with three subscales, for persistent and episodic anxiety, and avoidance behavior. It is easy and brief to administer. The general structure of the PAS was based on the outcome of a Delphi consensus procedure and the selection of items included in the scale was based on clinimetric analyses of items of two existing anxiety scales from a previous MJFF sponsored study on anxiety in Parkinson's disease.
Validation of this scale was done in a cross-sectional international multicenter study that included 362 patients with idiopathic PD. These patients underwent a single screening session in which the PAS was administered, along with other anxiety scales, as well as diagnostic interview to establish anxiety diagnoses. Properties for acceptability and reliability met predetermined criteria, and other clinimetric properties, including validity, were superior to those of existing anxiety rating scales.