Multiple balance tests improve the assessment of postural stability in subjects with Parkinson’s disease
- 1Neurological Sciences Institute, Oregon Health and Science University, Portland, OR, USA
- 2Department of Neurology, Oregon Health and Science University, Portland, OR, USA
- Correspondence to: Dr Fay B Horak Neurological Sciences Institute of Oregon Health and Science University, OHSU West Campus – Bldg 1, 505 NW 185th Avenue, Beaverton, OR 97006-3499, USA;
- Received 31 March 2005
- Accepted 12 October 2005
- Revised 27 September 2005
Objectives: Clinicians often base the implementation of therapies on the presence of postural instability in subjects with Parkinson’s disease (PD). These decisions are frequently based on the pull test from the Unified Parkinson’s Disease Rating Scale (UPDRS). We sought to determine whether combining the pull test, the one-leg stance test, the functional reach test, and UPDRS items 27–29 (arise from chair, posture, and gait) predicts balance confidence and falling better than any test alone.
Methods: The study included 67 subjects with PD. Subjects performed the one-leg stance test, the functional reach test, and the UPDRS motor exam. Subjects also responded to the Activities-specific Balance Confidence (ABC) scale and reported how many times they fell during the previous year. Regression models determined the combination of tests that optimally predicted mean ABC scores or categorised fall frequency.
Results: When all tests were included in a stepwise linear regression, only gait (UPDRS item 29), the pull test (UPDRS item 30), and the one-leg stance test, in combination, represented significant predictor variables for mean ABC scores (r2 = 0.51). A multinomial logistic regression model including the one-leg stance test and gait represented the model with the fewest significant predictor variables that correctly identified the most subjects as fallers or non-fallers (85% of subjects were correctly identified).
Conclusions: Multiple balance tests (including the one-leg stance test, and the gait and pull test items of the UPDRS) that assess different types of postural stress provide an optimal assessment of postural stability in subjects with PD.
- ABC scale, Activities-specific Balance Confidence scale
- PD, Parkinson’s disease
- PIGD, postural instability and gait difficulty
- SD, standard deviation
- UPDRS, Unified Parkinson’s Disease Rating Scale
This project was supported by NIH grant AG-06457
Competing interests: none declared
Ethics approval: subjects gave informed consent, and the protocol was approved by the Institutional Review Board of Oregon Health and Science University, Portland, OR