Is fatigue associated with balance in Parkinson's disease?

Abstract

Background: Fatigue is a disabling symptom in the spectrum of Parkinson's disease (PD), affecting from 30% to 70% of the persons. Even though it is a common symptom, with negative repercussions for PD individuals, its correlation with balance is not established. Aim: The aims of this study were to verify the correlation between fatigue and balance in individuals with PD and to compare balance in individuals with PD that presents low fatigue or high fatigue. Methods: This study included 37 individuals with PD, who were divided into two groups: low fatigue (n = 25) and high fatigue (n = 12). Fatigue was evaluated using the Parkinson's disease Fatigue Scale and a force platform was used to assess four balance tasks: bipedal, tandem with eyes open/closed, and tandem with the dual-task, in three parameters: (1) 95% confidence ellipse area of the center of pressure (COP) (2) mean velocity (3) root mean square of COP. To verify the correlation between fatigue and balance, the Spearman rank-order correlation coefficient was assessed.Comparison of medians between the groups was analyzed using the Mann-Whitney test. Results: There was no significant correlation between fatigue and balance. There was no difference between the groups with low and high fatigue. Conclusion:This study's findings, together with those reported in the literature, suggest there is no correlation between fatigue and balance, and even though individuals with PD report fatigue or experience situations of fatigue, they do not present greater posture instability than individuals with PD who do not report fatigue.