Fatigue is a common non-motor symptom in PD, which adversely and greatly affects PwP quality of life. It causes a reduction in energy level or an increased perception of effort which is not proportionate to the level of effort done.

Given its frequent occurrence in PD and significant impact on daily functions, it is important to monitor it to assess B1 therapy dose-related effects.

Fatigue (extreme tiredness) is often one of the first symptoms to improve with B1. The person affected feels more energy and able to carry out many more tasks in a day than usual, often without even realizing it.

Stocchi et al. reported that “distressing” fatigue (PFS-16 mean score ≥3.3) is associated with higher total Unified Parkinson’s Disease Rating Scale (UPDRS) scores and poorer quality of life in Italian PwP (Stocchi, 2014).

A useful tool to self-rate fatigue and monitor B1 therapy impact is the Parkinson Fatigue Scale (PFS-16) developed by Brown in 2005 (Brown, 2005).

It is a questionnaire consisting of 16 statements about fatigue in the past two weeks and how they impact on PwP daily activities.
The PFS-16 can be viewed at the Parkinson’s UK website at [external link].

It is simple to use and has a satisfactory test-retest reliability (Brown, 2005). Fatigue severity may also be associated with PD prognosis.

Brown grants permission for its use in clinical management and in not-for profit research.

The PFS tool may be useful to carefully observe the effects of B1 therapy on slowing down worsening of symptoms if there is fatigue.

It has been suggested that questions 14 and 16 in the PFS-16 may represent ongoing neuro-inflammatory processes in PwP (Niimi, 2019).

Selected references

Stocchi F, Abbruzzese G, Ceravolo R, Cortelli P, D’Amelio M, De Pandis MF, Fabbrini G, Pacchetti C, Pezzoli G, Tessitore A, Canesi M, Iannacone C, Zappia M. Prevalence of fatigue in Parkinson disease and its clinical correlates. Neurology 2014; 83: 215–220.

Brown RG, Dittner A, Findley L, Wessely SC. The Parkinson fatigue scale. Parkinsonism Relat Disord. 2005 Jan;11(1):49-55.

Niimi Y, Shima S, Mizutani Y, Ueda A, Ito S, Mutoh T. Fatigue evaluated using the 16-item Parkinson Fatigue Scale (PFS-16) predicts Parkinson's disease prognosis. Fujita Med J. 2019;5(2):45-48.

Text author: Sergio Pièche
Page updated - 24/04/23