Effect of Dopaminergic Medication on Postural Sway in Advanced Parkinson’s Disease

Fredy J Revilla,Paul Succop,Ashutosh Mani,Travis R Larsh,Amit Bhattacharya,Andrew P Duker,Maureen Gartner,Cyndy Cox,Claudia Jarrin Tejada

doi:10.3389/fneur.2013.00202

Abstract

Background: The effect of dopaminergic therapy on balance in Parkinson’s disease (PD) remains unclear, including previous studies that excluded the effect of dyskinesias or other involuntary movements on postural sway. Additionally, medication’s effects may differ between fallers and non-fallers. In this study, the authors quantify the effect of dopaminergic medication on postural balance (sway) in advanced PD, with and without dyskinesias, and consider the patient’s history of falls.Methods: In 24 patients with advanced idiopathic PD, postural balance was measured using a strain-gage force platform. Before and after taking dopaminergic medication, the patient’s postural sway was measured at 30-s intervals to determine sway length (SL) and sway area (SA). Data analysis included the presence of dyskinesias during “ON” medication condition and history of previous falls.Results: No significant changes occurred in SL or SA with dopaminergic treatment for fallers without dyskinesias or non-fallers with dyskinesias. However, after dopaminergic treatment, SL and SA were 37.8 and 45% lower, respectively, in non-fallers without dyskinesias (indicating better balance) and were 87.4 and 162.8% higher, respectively, in fallers with dyskinesias (indicating poorer balance). In the ON-medication condition, SL and SA were larger in patients with dyskinesias when compared with patients without dyskinesias; SL was larger in fallers than non-fallers in both groups with or without dyskinesias.Conclusion: Dopaminergic medication effects on postural sway could be a predictive factor for fall risk in PD patients with and without dyskinesias: specifically, decreased sway could indicate minimal fall risk whereas no change or increased postural sway could indicate a high risk.

Highlights

Factors contributing to balance impairment in Parkinson’s disease (PD) patients include disturbed postural reflexes, poor control of voluntary movements, and side effects of certain medications that include dyskinesias and orthostatic hypotension [1, 2]
No significant changes occurred in sway length (SL) or sway area (SA) with dopaminergic treatment for fallers without dyskinesias or non-fallers with dyskinesias
Dopaminergic medication effects on postural sway could be a predictive factor for fall risk in PD patients with and without dyskinesias: decreased sway could indicate minimal fall risk whereas no change or increased postural sway could indicate a high risk

Summary

Introduction

Factors contributing to balance impairment in Parkinson’s disease (PD) patients include disturbed postural reflexes, poor control of voluntary movements, and side effects of certain medications that include dyskinesias and orthostatic hypotension [1, 2]. Several studies have found that postural sway, a marker of balance impairment characterized by motion of the body’s center of pressure (CoP), is increased by dopaminergic treatment in patients with advanced PD [3, 4]. These studies did not account for the effects of dyskinesias or other involuntary movements on postural sway. The effect of dopaminergic therapy on balance in Parkinson’s disease (PD) remains unclear, including previous studies that excluded the effect of dyskinesias or other involuntary movements on postural sway. The authors quantify the effect of dopaminergic medication on postural balance (sway) in advanced PD, with and without dyskinesias, and consider the patient’s history of falls

Methods

Results

Discussion

Conclusion