An Objective Study of Fatigue in Parkinson’s Disease

Benzi Kluger M.D.

Epidemiology of Fatigue

• Fatigue is one of the most frequent and disabling symptoms in medicine

• Prevalence is estimated at 20% for the general population

• It has a significant effect on quality of life for several diseases including stroke, Parkinson’s Disease (PD) and multiple Sclerosis

Significance of Fatigue in PD

• The majority of studies demonstrate a 40% prevalence of severe fatigue in PD

• 1/3 of PD patients report it is one of their most disabling symptoms

• We currently do not understand its cause and have no effective treatments.

Definition

1) Feelings of tiredness, weariness, or exhaustion (subjective or perceived fatigue).

2) A reduction in the capacity to perform a task, as a result of previous performance on the same task (objective fatigue).

3) Changes in other activities and capacities (including changes in physiological function and changes in the ability to perform other activities).

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Comparison of Baseline Performance

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Objective Fatigue as Measured by Percent Change in Task Performance

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Variance in Median Reaction Time as a Function of Fatigue

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