Association of sleep disturbance and freezing of gait in Parkinson disease: Prevention/delay implications

Abstract

StudyObjectives: Freezing of gait (FOG) severely impairs life quality of Parkinson disease (PD) patients. The relationship between sleep disturbance and FOG in PD remains unclear, so in this study, we aimed to investigate that relationship. Methods: First, we assessed clinical characteristics of freezers and nonfreezers among PD patients. Next, we assessed clinical characteristics of PD patients with different PDSS1 scores (score on first item of Parkinson's Disease Sleep Scale). Finally, we prospectively followed a cohort of nonfreezers from a baseline clinical visit and to amaximum of 18 months and performed a Cox regression analysis to further investigate the relationship between PDSS1 score and FOG inPD. Results: A total of 163 participantswith PDwere included in the baseline analysis. The freezers had significantly worse sleep compared with the nonfreezers. The proportion of freezers in the patients with low PDSS1 score (PDSS1 < 6) was significantly higher than that in the patients with high PDSS1 score (PDSS1 ≥ 6). A total of 52 nonfreezers were prospectively followed. During amaximum18-month follow-up, FOG incidence (73%) in the PDSS1 < 6 group was significantly higher than that (24%) in the PDSS1 ≥ 6 group (P = .008). Low PDSS1 score (hazard ratio = 4.23, 95% CI 1.64-10.92, P =.003) and high levodopa equivalent daily dose (hazard ratio = 4.18, 95% CI 1.62-10.75, P = .003) were significantly associated with an increased hazard of FOG. Conclusions: Our study indicated that lowPDSS1 score may be a risk indicator for the development of FOGand provided important insights into potential targets for the prevention/delay of FOG in PD.