Postural sensory correlates of freezing of gait in Parkinson's disease

Introduction: To elucidate the unique patterns of postural sensory deficits contributing to freezing of gait (FOG) in patients with Parkinson's disease (PD) and to identify postural sensory modalities that correlate with FOG severity. Methods: Twenty-five PD patients with FOG, 22 PD patients without FOG, and 26 age-matched controls were evaluated using a sensory organization test and clinical measures including the Unified Parkinson's Disease Rating Scale motor score, Montreal Cognitive Assessment, Frontal Assessment Battery, Activities specific Balance Confidence, Beck Anxiety Inventory, Beck Depression Inventory, and Berg Balance Scale. Multivariable logistic regression analysis was performed for posturographic parameters and possible confounders to determine postural sensory contributors to FOG. We also correlated FOG severity, measured using a New Freezing of Gait Questionnaire, with posturographic parameters. Results: PD patients with FOG showed worse postural sensory processing compared with those without FOG. In particular, the inability to use the vestibular information (odds ratio [OR] 1.447; 95% confidential interval [CI]: 1.120, 1.869) and poor control over the perturbed somatosensory inputs (OR 2.904; 95% CI: 1.028, 8.202) significantly contributed to FOG. Among PD patients with FOG, FOG severity was correlated with higher reliance on visual information (rho = -0.432, p = 0.039). Conclusions: Postural sensory deficits involving specific sensory modalities are strongly associated with FOG. Quantitative measurement of postural sensory deficits in PD patients with FOG may provide a better understanding of pathomechanisms of FOG and increase the efficacy of sensory cueing strategies for alleviating FOG, by more accurately identifying suitable patients for rehabilitative therapies. (C) 2016 Elsevier Ltd. All rights reserved.