Clinical characteristics of fatigued Parkinson's patients and the response to dopaminergic treatment

The Impact of Fatigue on Sleep and Other Non-Motor Symptoms in Parkinson's Disease

Fatigue is a common non-motor symptom in Parkinson's disease (PD), but even so, it may still be underdiagnosed or misdiagnosed in current practice due to its non-specific manifestations. The aims of this study were to investigate the prevalence of fatigue in PD patients compared to healthy controls and to identify the main characteristics and associations of fatigue with other non-motor symptoms and the impact of fatigue on sleep disturbances in Parkinson's disease.

MATERIALS AND METHODS

case-control study in which 131 PD patients and 131 age- and sex-matched controls were enrolled. Main characteristics of fatigue, sleep, and other non-motor symptoms were assessed using specific validated questionnaires.

RESULTS

According to the Chalder fatigue scale, fatigue is more prevalent in PD patients (38.16%) compared to healthy controls (26.71%). Fatigue was identified in 46.54% of the PD patients using the Parkinson's Fatigue Scale (PFS-16). PD patients with fatigue presented a worse motor status, more sleep disturbances (insomnia, daytime sleepiness), a broader spectrum of non-motor symptoms (pain, anxiety, urinary disturbances), worse cognitive performances, a lower level of happiness, and worse quality of life compared to PD patients without fatigue.

CONCLUSION

Fatigue is a common symptom of PD and needs to be assessed, considering its consequences on quality of life. Sleep disturbances have a great influence over fatigue in PD patients.

Characteristics of fatigue in Parkinson’s disease: A longitudinal cohort study

Objective

To assess the prevalence, evolution, clinical characteristics, correlates and predictors of fatigue as well as to investigate the influence of comorbid fatigue on the longitudinal changes in motor and non-motor symptoms over a 2-year longitudinal follow-up period in a large cohort of patients with Parkinson’s disease (PD).

Materials and methods

A total of 2,100 PD patients were enrolled from the Parkinson’s Disease & Movement Disorders Multicenter Database and Collaborative Network in China (PD-MDCNC), and their motor and non-motor symptoms were assessed biennially using comprehensive scales, including the 16-item Parkinson Fatigue Scale (PFS-16). Each PD patient was categorized as PD with or without fatigue on the basis of a cut-off mean PFS-16 score of 3.3.

Results

The prevalence of fatigue in our cohort was 36.8%. Compared to PD patients without fatigue, PD patients with fatigue were more likely to be older, have a longer disease duration, and higher baseline levodopa equivalent daily dose (all p < 0.05). Moreover, PD patients with fatigue showed more severe motor and non-motor phenotypes than those without fatigue. Overall, high total Unified Parkinson’s Disease Rating Scale (UPDRS) score (odds ratio [OR] = 1.016, 95% confidence interval [CI]: 1.009–1.024), Non-Motor Symptoms Scale score (OR = 1.022, 95% CI: 1.015–1.029), postural instability and gait difficulty (PIGD) subtype (OR = 1.586, 95% CI: 1.211–2.079), presence of excessive daytime sleepiness (EDS; OR = 1.343, 95% CI: 1.083–1.666), and wearing-off (OR = 1.282, 95% CI: 1.023–1.607) were significantly associated with fatigue in PD patients (all p < 0.05). High total UPDRS score at baseline (OR = 1.014, 95% CI: 1.002–1.027, p = 0.028) increased the risk of developing fatigue during follow-up. Although significant, the odds ratios were low and confidence intervals were narrow. Analysis of disease progression showed significant group differences in motor and non-motor symptoms. In comparison with the never-fatigue group, the persistent-fatigue group showed significantly greater progression in motor, autonomic dysfunction, sleep, depression and cognitive symptoms (all p < 0.05).

Conclusion

Increased disease severity, presence of the PIGD subtype, EDS, and wearing-off were associated with fatigue in PD patients. Significant subgroup-level differences were observed in the progression of motor and non-motor symptoms across different fatigue subgroups of PD patients.

Neuroprotective Effects of Resveratrol in In vivo and In vitro Experimental Models of Parkinson's Disease: a Systematic Review

Parkinson's disease (PD) is currently the second most common neurodegenerative disease, being characterized by motor and non-motor symptoms. The therapeutic options available for its treatment are limited, do not slow the progression of the disease, and have serious side effects. For this reason, many studies have sought to find compounds with neuroprotective properties that bring additional benefits to current therapy. In this context, resveratrol is a phenolic compound, found in many plant species, capable of crossing the blood-brain barrier and having multiple biological properties. Experimental studies in vitro and in vivo have shown that it can prevent or slow the progression of a variety of diseases, including PD. In this systematic review, we summarize the effects of resveratrol in experimental in vivo and in vitro models of PD and discuss the molecular mechanisms involved in its action. The bibliographic search was performed in the databases of PubMed, Web of Science, SciELO, and Google Scholar, and based on the inclusion criteria, 41 articles were selected and discussed. Most of the included studies have demonstrated neuroprotective effects of resveratrol. In general, resveratrol prevented behavioral and/or neurological disorders, improved antioxidant defenses, reduced neuroinflammatory processes, and inhibited apoptosis. In summary, this systematic review offers important scientific evidence of neuroprotective effects of resveratrol in PD and also provide valuable information about its mechanism of action that can support future clinical studies.

Effects of a structured dance program in Parkinson's disease. A Greek pilot study

INTRODUCTION

Dance for Parkinson's Disease® (DfPD®) is a structured dance program that has never been evaluated in Greek PD population. This study assesses for the first time the efficacy, safety and feasibility of DfPD® program in Greek PD patients.

MATERIAL AND METHODS

A total of 16 early-to-mid-stage PD patients (50% men, aged 56 ± 12) underwent a total of 16 60-min classes of adjusted to Greek music and dance culture DfPD®, twice weekly, over 8 weeks. Assessments were performed at baseline and at the end of the study period and included quality of life (PDQ-8), depressive symptoms (BDI-II), fatigue (PFS-16), cognitive functions (MoCA), balance (BBS) and body mass index (BMI). Safety (possible falls, injuries, muscle soreness or excessive fatigue) and feasibility (technical and financial parameters, willingness for participation and continuation, recruitment rates) were also assessed.

RESULTS

Statistically significant improvements were found in quality of life (29 ± 47%, p = 0,020), depressive symptoms (26 ± 52%, p = 0,046), fatigue (13 ± 20%, p = 0,021), cognitive functions (17 ± 23%, p = 0,010), balance (5 ± 4%, p = 0,003) and BMI (2 ± 2%, p = 0,010). No adverse events, high adherence (93,75%) and low attrition (12,5%) rates were reported.

CONCLUSION

A twice weekly 60-min DfPD® class for 8 weeks is a safe and feasible non-pharmacological complementary therapeutic intervention for Greek PD patients and may improve their quality of life, depressive symptoms, fatigue, cognitive functions, balance, and BMI. Further research on this intervention is warranted.

Understanding the influence of pain and fatigue on physical performance, fear of falling and falls in people with Parkinson's disease: a pilot study

Objective: Pain and fatigue are highly prevalent debilitating symptoms in Parkinson's disease (PD), however, their relationship with physical performance, fear of falling (FOF) and falls is not clear. We aim in this pilot study to investigate the relationship of pain and fatigue with physical performance, FOF and falls in people with Parkinson's disease (PwPD). Materials & methods: 53 PD patients were assessed for fall history, physical performance, FOF, pain and fatigue. Results: Pain and fatigue are significantly associated with physical performance and FOF (p ≤ 0.002). Pain and fatigue were different between fallers and non-fallers (p < 0.5), but only fatigue could distinguish fallers from non-fallers (area under the receiver operating characteristics curve = 0.81; p < 0.0001). Conclusion: This pilot study indicated that FOF in PwPD is significantly associated with pain and fatigue. Furthermore, fatigue level is related to fall history. By addressing pain and fatigue, we may ameliorate the deterioration of FOF and falls in PwPD.

Triggers and alleviating factors for fatigue in Parkinson's disease

BACKGROUND

Fatigue is common in Parkinson's Disease, but few effective treatments are available for it. Exploring triggers and alleviating factors, including effects of exercise, could inform development of management strategies for Parkinson's Disease fatigue.

OBJECTIVES

To examine triggers and alleviating factors for fatigue reported by individuals with Parkinson's Disease, including perceived effect of exercise.

METHODS

A sample of individuals with self-reported Parkinson's Disease participating in the study Fox Insight were administered an online survey. The survey included the Parkinson's Fatigue Scale, the Physical Activity Scale for the Elderly, and multiple-choice questions about triggers and alleviating factors for fatigue.

RESULTS

Among the sample of 1,029 individuals with Parkinson's disease, mean (standard deviation (SD)) age was 67.4 (9.3) years, 44.0% were female. Parkinson's Fatigue Scale score ranged from 16-80, mean (SD) 48.8 (16.2). Poor sleep (62.1%) and physical exertion (45.1%) were frequently reported triggers for fatigue. Coping strategies including sitting quietly (58.1%), laying down with or without napping, and exercise (20%). Physical Activity Scale for the Elderly scores were higher in those who reported that exercise alleviated their fatigue (49.7%) compared to those who reported it worsened their fatigue (18.9%) (mean (SD) score 158.5 (88.8) vs 119.8 (66.6) respectively; p<0.001).

CONCLUSIONS

Several behavioral and environmental triggers and alleviating strategies for fatigue are reported by individuals with Parkinson's disease. Many feel that exercise alleviates fatigue, though the relationship between exercise and fatigue in Parkinson's Disease appears complex. This exploratory study may inform future development of treatments or coping strategies for Parkinson's disease fatigue.

Fatigue correlates with sleep disturbances in Parkinson disease

BACKGROUND

Many Parkinson disease (PD) patients complain about chronic fatigue and sleep disturbances during the night. The objective of this study is to determine the relationship between fatigue and sleep disturbances by using polysomnography (PSG) in PD patients.

METHODS

Two hundred and thirty-two PD patients (152 with mild fatigue and 80 with severe fatigue) were recruited in this study. Demographic information and clinical symptoms were collected. Fatigue severity scale (FSS) was applied to evaluate the severity of fatigue, and PSG was conducted in all PD patients. FSS ≥4 was defined as severe fatigue, and FSS <4 was defined as mild fatigue. Multivariate logistic regression and linear regression models were used to investigate the associations between fatigue and sleep disturbances.

RESULTS

Patients with severe fatigue tended to have a longer duration of disease, higher Unified Parkinson Disease Rating Scale score, more advanced Hoehn and Yahr stage, higher daily levodopa equivalent dose, worse depression, anxiety, and higher daytime sleepiness score. In addition, they had lower percentage of rapid eye movement (REM) sleep (P = 0.009) and were more likely to have REM sleep behavior disorder (RBD) (P = 0.018). Multivariate logistic regression analyses found that the presence of RBD and proportion of REM sleep were the independent predictors for fatigue. After the adjustment of age, sex, duration, body mass index, severity of disease, scores of Hamilton Rating Scale for Depression, Hamilton Anxiety Rating Scale, and other sleep disorders, proportion of REM sleep and degree of REM sleep without atonia in patients with PD were still associated with FSS score.

CONCLUSION

Considering the association between fatigue, RBD, and the altered sleep architecture, fatigue is a special subtype in PD and more studies should be focused on this debilitating symptom.

Effects of Cognitive Performance and Affective Status on Fatigue in Parkinson's Disease

Background

Fatigue is a common non-motor symptom in Parkinson's disease (PD) and is typically assessed via self-reported questionnaires such as the Parkinson's Fatigue Scale (PFS). The PFS captures the presence of subjective experience of physical fatigue as well as its impact on daily functioning.

Objectives

We aimed to investigate whether different variables (cognition, neuropsychiatric symptoms, disease-related measures) are associated with the experience of physical fatigue in comparison to fatigue affecting daily functioning.

Method

Sixty-two non-demented PD patients were evaluated through questionnaires assessing fatigue, daytime sleepiness, apathy, depression, anxiety, and cognition. Items of fatigue were classified and summarized into two index variables measuring either the subjective experience of physical fatigue or the impact of fatigue on daily functioning. Linear regression with a stepwise elimination procedure was conducted to select the significant predictors for each index variable separately.

Results

Subjective experience of physical fatigue (Model 1; r² = 0.46; p <0.01) was significantly associated with higher levels of depression (b =0.07; p <0.01), anxiety (b =0.03; p <0.05), and lower performances in verbal episodic memory (b =-0.16; p <0.05). Fatigue affecting daily functioning (Model 2; r² = 0.44; p <0.05) was significantly related to higher levels of depression (b = 0.07; p < 0.01), anxiety (b = 0.03; p > 0.05), and lower motor functioning (b = 0.01; p = 0.05).

Conclusions

In conclusion, our work supports associations between fatigue and other neuropsychiatric symptoms in PD and extends prior work suggesting that motor disturbances are specifically linked to fatigue-related impairment of daily functioning, but not to the subjective experience of physical fatigue.

Dopamine Replacement Medication Does Not Influence Implicit Learning of a Stepping Task in People With Parkinson's Disease

INTRODUCTION

Treatment of Parkinson's disease (PD) with exogenous dopamine (ie, levodopa) may positively affect motor symptoms, but may negatively affect other functions such as the learning of motor skills necessary for rehabilitation. This study aimed to determine whether levodopa medication affects general and sequence-specific learning of a stepping task and the transfer of movement skill to untrained balance tasks in people with PD.

METHODS

Participants with PD were randomized to practice "on" (n = 14) or "off" (n = 13) levodopa medication. Participants practiced 6 blocks of 6 trials of 24 steps of a stepping task over an acquisition period of 3 consecutive days, followed by single retention blocks of 6 trials 2 and 9 days later. Participants were also assessed on untrained balance (ie, transfer) tasks "on" levodopa before practice and following late retention.

RESULTS

There were no between-group differences in general learning, sequence-specific learning, or transfer of skill to untrained balance tasks ( P > .05). Both groups demonstrated general and sequence-specific learning ( P < .001) and trends for improvement in untrained tasks ( P < .001 to P = .26) following practice. Detailed analysis of early acquisition revealed no difference between medication groups.

CONCLUSION

People with PD improved performance on the stepping task with practice. The between-group effect sizes were small, suggesting that levodopa medication status ("on" versus "off") during practice did not significantly affect general or sequence-specific learning of the task or components of early acquisition. The practice dose required to optimally result in functional improvements in untrained balance tasks, including reductions in falls, remains to be determined.

Fatigue in Parkinson's disease: A systematic review and meta-analysis

We conducted a systematic review and meta-analysis aimed at establishing robust prevalence estimates and identifying clinical correlates of fatigue in PD. From 2,459 titles and abstracts, we selected 44 relevant studies (n = 7427 patients). Overall, the meta-analysis showed a prevalence of fatigue of 50% in PD. This prevalence estimate, however, was significantly moderated by study heterogeneity in measurement scales and cut-off thresholds. In contrast, demographic features, disease severity, cognitive impairment, and depression did not moderate prevalence estimates. Moreover, fatigue prevalence did not differ between de novo and treated PD patients. Compared to nonfatigued patients, fatigued patients had sligthly higher age (1.44 years), disease duration (0.93 years), l-dopa equivalent daily dose (50.89 units), UPDRS-III (4.99 points), and H & Y (0.33 points), as well as risk of comorbid depression (risk ratio = 1.89) and had a little lower MMSE score (-0.66 points). Fatigue was moderately associated with apathy (Hedges' g = 0.55), anxiety (Hedges' g = 0.67), daytime somnolence (Hedges' g = 0.43), sleep disturbances (Hedges' g = 0.66), and poorer quality of life (Hedges' g = 1.23). Our analyses suggest that fatigue is a frequent, independent nonmotor symptom in PD appearing early and persisting throughout the disease course, and that establishing uniform diagnostic criteria for PD-related fatigue is critical. In addition, several nonmotor symptoms appear to be associated with fatigue and negatively impact quality of life. Pharmacological and nonpharmacological interventions targeting fatigue and associated symptoms may improve quality of life in patients with PD. © 2018 International Parkinson and Movement Disorder Society.

Structural and Functional Brain Patterns of Non-Motor Syndromes in Parkinson's Disease

Parkinson’s disease (PD) is a common, progressive and multisystem neurodegenerative disorder characterized by motor and non-motor symptoms. Advanced magnetic resonance imaging, positron emission tomography, and functional magnetic resonance imaging can render the view toward understanding the neural basis of these non-motor syndromes, as they help to understand the underlying pathophysiological abnormalities. This review provides an up-to-date description of structural and functional brain alterations in patients with PD with cognitive deficits, visual hallucinations, fatigue, impulsive behavior disorders, sleep disorders, and pain.

Fatigue in Parkinson's disease: concepts and clinical approach

Parkinson's disease (PD) is a progressive neurological disorder characterized by a large number of motor and non-motor features. Fatigue is one of the most common and most disabling symptoms among patients with PD, and it has a significant impact on their quality of life. Although fatigue has been recognized for a long time, its pathophysiology remains poorly understood, and there is no evidence to support any therapeutic approach in PD patients. Expert consensus on case definition and diagnostic criteria for PD-related fatigue have been recently published, and although they still need to be adequately validated, they provide a great step forward in the study of fatigue. The goal of this article is to provide relevant information for the identification and management of patients with fatigue.

Fatigue correlates with LRRK2 G2385R variant in Chinese Parkinson's disease patients

INTRODUCTION

Fatigue is common in patients with Parkinson's disease (PD). The leucine-rich repeat kinase 2 (LRRK2) G2385R variant predisposes individuals to develop PD in China. The aim of this study was to evaluate whether the LRRK2 G2385R variant is associated with fatigue in patients with PD.

METHODS

Fatigue was evaluated by the Parkinson Fatigue Scale (PFS) in 329 PD patients and 180 controls, a cut-off score of ≥3.3 was used to define the presence of fatigue. All the enrolled PD patients were assessed by a comprehensive battery of motor and non-motor questionnaires. PD patients were genotyped for the G2385R variant. Associations of fatigue with the clinical assessments and with the G2385R variant in PD patients were analyzed by logistic regression.

RESULTS

Fatigue frequency was 55.62%. A logistic regression model found that the female sex (OR = 10.477; 95%CI: 2.806-39.120; p < 0.001), motor function (OR = 1.060; 95%CI: 1.012-1.110; p = 0.013), sleep disturbance (OR = 0.943; 95%CI: 0.910-0.976; p = 0.001) and depression severity (OR = 0.843; 95%CI: 0.736-0.965; p = 0.013) collectively predict the presence of fatigue in PD patients. After adjustment for demographics and associated clinical factors, the G2385R variant was associated with an increased risk for the presence of fatigue (OR = 10.699; 95% CI = 2.387-47.958; p = 0.002) in the PD population in this study.

CONCLUSION

We confirm that fatigue in PD patients is common, and we have strengthened the associations between fatigue and female sex, motor severity and non-motor symptoms, particularly depression and sleep disturbances. Overall, we found that carriers of the G2385R variant were more prone to fatigue than non-carriers in PD patients.

Validation of the Parkinson Fatigue Scale in Chinese Parkinson's disease patients

OBJECTIVE

Fatigue is a common nonmotor symptom in Parkinson's disease (PD); however, the Parkinson's disease fatigue scale (PFS), which is designed to measure fatigue in PD, has not been validated in China. The aim of this study was to determine the validity and reliability of the Chinese version of the PFS in PD patients.

METHODS

A total of 115 PD patients were evaluated at baseline and after 7 days. Assessments included the PFS, the Fatigue Severity Scale (FSS), and scales assessing motor, cognition, depression, and anxiety. Acceptability was assessed in terms of the rate of missing data and floor and ceiling effects. Cronbach's alpha was calculated to determine internal consistency. Test-retest reliability was assessed using the intraclass correlation coefficient (ICC). Spearman's rank correlation coefficients were used to calculate convergent and divergent validity between PFS scores and scales assessing clinical characteristics.

RESULTS

No data were missing for the PFS. Compared with the original scoring method, the binary scoring method had relatively large floor effects (5.21% vs. 17.39%) and ceiling effects (0.90% vs. 4.31%). The internal consistency and test-retest reliability of the PFS were satisfactory (original scoring method: Cronbach's alpha = 0.97, ICC = 0.94; binary scoring method: Cronbach's alpha = 0.94, ICC = 0.94). The PFS score exhibited strong convergent validity with FSS score (correlation coefficient = 0.87). PFS score was weakly to moderately correlated with disease duration and with measures of disease stage, motor function, depression, and anxiety (range of correlation coefficients: 0.25-0.48). There was no significant correlation between PFS score and either onset age or MoCA score (range of correlation coefficients: -0.05 to 0.12).

CONCLUSION

The Chinese version of the PFS is a valid measure for assessing fatigue in PD.

Serotonergic dysfunctions and abnormal iron metabolism: Relevant to mental fatigue of Parkinson disease

Fatigue is a very common non-motor symptom in Parkinson disease (PD) patients. It included physical fatigue and mental fatigue. The potential mechanisms of mental fatigue involving serotonergic dysfunction and abnormal iron metabolism are still unknown. Therefore, we evaluated the fatigue symptoms, classified PD patients into fatigue group and non-fatigue group, and detected the levels of serotonin, iron and related proteins in CSF and serum. In CSF, 5-HT level is significantly decreased and the levels of iron and transferrin are dramatically increased in fatigue group. In fatigue group, mental fatigue score is negatively correlated with 5-HT level in CSF, and positively correlated with the scores of depression and excessive daytime sleepiness, and disease duration, also, mental fatigue is positively correlated with the levels of iron and transferrin in CSF. Transferrin level is negatively correlated with 5-HT level in CSF. In serum, the levels of 5-HT and transferrin are markedly decreased in fatigue group; mental fatigue score exhibits a negative correlation with 5-HT level. Thus serotonin dysfunction in both central and peripheral systems may be correlated with mental fatigue through abnormal iron metabolism. Depression, excessive daytime sleepiness and disease duration were the risk factors for mental fatigue of PD.