The Impact of Dual-Tasking on Postural Stability in People With Parkinson’s Disease With and Without Freezing of Gait

摘要

Background . Postural instability and freezing of gait (FOG) are major problems in patients with Parkinson’s disease (PD), and both contribute to falls. However, the interrelationship between these 2 deficits is still unclear. Objective . This study investigated whether dual-tasking influenced postural control differently in freezers (FOG+) and nonfreezers (FOG?). Methods . Thirty-three patients with PD (19 FOG+, 14 FOG?, well-matched) and 28 healthy controls underwent 4 postural control tasks, consisting of standing on either stable or unstable surfaces with eyes open or closed. Each condition was performed with and without a cognitive dual-task (DT). Center of pressure and center of mass variables and cognitive DT performance outcomes were investigated. Results . Postural stability decreased to a larger extent in FOG+ under DT conditions compared with the other groups, although overall most differences were found between FOG+ and controls. FOG+ exhibited worse postural control compared with FOG? under stable surface DT conditions, shown by higher medial-lateral sway measures (group × surface × task, P Conclusions . Postural stability in FOG+ deteriorated more than in FOG? and controls upon cognitive load. Our results extend earlier findings on gait that the compensatory mechanisms to cope with DT stance are insufficient in FOG+. The findings highlight the need for adapted rehabilitation programs for this subgroup, comprising motor-cognitive balance training.