The influence of fatigue on health-related quality of life in patients with Parkinson's disease

Objective - To examine the correlation between fatigue and health-related quality of life (HRQL) in patients with Parkinson's disease (PD). Patients and methods - Sixty-six patients with idiopathic PD. The patients did not have a depressive mood disorder or cognitive impairment. Fatigue was measured by the Fatigue Severity Scale (FSS). HRQL was measured by the Parkinson's Disease Questionnaire (PDQ-39) and the Short-Form 36 (SF-36). Results - Thirty-three (50%) of the patients had significant fatigue. Patients with fatigue had a more advanced disease than those without fatigue, measured by the UPDRS scale, including a higher Hoehn and Yahr stage and lower Schwab and England score. Patients with fatigue reported more distress in the dimensions of emotional well-being and mobility (PDQ-39) and also had a significantly higher PDQ summary index. On the SF-36 patients with fatigue reported more problems in the areas of physical functioning, role limitation (physical), social functioning and vitality. Correlations between the FSS and the HRQL scales were highest for the summary index of PDQ-39 and in the dimensions of ADL, mobility and emotional well-being (PDQ-39) and physical functioning, role limitation (physical), social functioning, general health and vitality (SF-36). Conclusions - PD has a substantial negative impact on HRQL. We found a strong correlation between fatigue and high distress scores on HRQL scales in a population of patients with PD who were not depressed or demented. The diversity of symptoms and high prevalence of non-motor features, including fatigue, is important to take into account in our efforts to optimize treatment and care for this patient group.