Progression of fatigue in Parkinson's disease - a 9-year follow-up.

BACKGROUND AND PURPOSE: Although highly disabling, the pathogenesis and evolution of fatigue in Parkinson's disease (PD) is largely unknown, and no sufficiently documented treatment currently exists. The aim of the present study was to investigate the evolution of fatigue during the first 9 years after diagnosis. METHODS: This study is part of the Norwegian ParkWest collaboration, a prospective population-based longitudinal cohort study. The present study comprised 191 newly diagnosed patients and 170 control participants. Fatigue was assessed by the Fatigue Severity Scale, with examinations at baseline and then every other year up to 9 years of follow-up. Linear mixed models were applied to investigate possible variables associated with fatigue. RESULTS: It was found that there was a statistically significant increase in the proportion of PD patients with fatigue during the first 9 years after diagnosis. A large proportion of patients had a significant increase or decrease in fatigue score between consecutive visits. In addition, the relative risk of persistent fatigue and ever having fatigue was higher than for controls. There were statistically significant longitudinal associations between higher levels of fatigue and female gender, comorbidity at baseline, depressive symptoms, dependency in activities of daily living and better cognitive functioning. Lower levels of fatigue were associated with the use of dopamine agonists. CONCLUSION: Fatigue is a common, severely limiting symptom in PD. This study demonstrates associations with other factors that could yield a better understanding of the symptom and thus possible treatment strategies, although further investigations are necessary to establish causal relationships.

Fatigue in early Parkinson's disease: the Norwegian ParkWest study.

BACKGROUND AND PURPOSE: Fatigue is a common and disabling non-motor symptom in Parkinson's disease (PD). The pathogenesis is unknown, and the treatment options are limited. The aim of the present study was to investigate the development of fatigue during the first year after diagnosis. METHODS: The study design was a prospective, controlled population-based longitudinal cohort study, comprising 181 de novo, drug-naïve patients with PD and 162 control participants. PD was diagnosed according to the Gelb criteria. Fatigue was assessed by the Fatigue Severity Scale (FSS). Both groups were assessed for fatigue at baseline and after 1 year. RESULTS: Patients reported more fatigue than the control subjects at baseline and at the 1-year follow-up evaluation. The FSS scores in the patient group improved from a mean score of 4.4 (SD 1.6) to 4.0 (SD 1.6). Patients with fatigue at baseline received higher doses of dopaminergic medication during follow-up. Patients who received dopamine agonists improved slightly more than patients who received levodopa. A regression analysis did not show a correlation between an improvement in fatigue and a change in disease severity, depressive symptoms, sleep problems, apathy or cognitive impairment. CONCLUSION: Fatigue is a common symptom in PD, also in early, untreated patients. During the first year of observation, an improvement in the fatigue scores was found. The improvement could not be attributed to a change in disease severity or depressive symptoms. The results indicate a better effect of dopamine agonists than of levodopa. This may have implications for treatment in patients with PD-associated fatigue.

Fatigue in early Parkinson's disease. Minor inconvenience or major distress?

BACKGROUND AND PURPOSE: Although fatigue is recognized as a common and debilitating symptom in patients with Parkinson's disease (PD), little is known on how and when this symptom emerges during disease progression. The aim of the study was to explore the presence and severity of fatigue in patients with PD at the time of diagnosis, before dopaminergic treatment has been instituted. METHODS: The present study is part of the Norwegian ParkWest project, a large cohort study of patients with incident PD in Norway. PD was diagnosed according to the Gelb criteria. The study population comprised 199 patients with untreated, newly diagnosed PD and 172 control subjects, matched for gender and age. Fatigue was measured by the Fatigue Severity Scale (FSS). RESULTS: Fifty-five percent of the patients with PD had clinical significant fatigue (FSS > 4), compared with about 20% of the controls (RR = 2.9). The mean score in patients on the FSS was 4.4 (SD 1.7) and in controls 3.1 (SD 1.3). In addition, there were highly significant differences between patients and controls in each of the nine FSS items. In a regression analysis, only the Montgomery and Åsberg Depression Rating Scale and Unified Parkinson's Disease Rating Scale-Activities of Daily Living scores were significantly associated with fatigue. There was no correlation between fatigue and cognitive impairment and hypersomnia. CONCLUSION: Fatigue is a common symptom in PD, also in patients with early, untreated disease, and it has a negative impact on these patients' activity of daily living. Also in early PD, fatigue is an important consideration in the management of patients with the disease.