The Pathophysiology of Fatigue in Parkinson's Disease and its Pragmatic Management

Parkin R274W mutation affects muscle and mitochondrial physiology

Recessive mutations in the Parkin gene (PRKN) are the most common cause of young-onset inherited parkinsonism. Parkin is a multifunctional E3 ubiquitin ligase that plays a variety of roles in the cell including the degradation of proteins and the maintenance of mitochondrial homeostasis, integrity, and biogenesis. In 2001, the R275W mutation in the PRKN gene was identified in two unrelated families with a multigenerational history of postural tremor, dystonia and parkinsonism. Drosophila models of Parkin R275W showed selective and progressive degeneration of dopaminergic neuronal clusters, mitochondrial abnormalities, and prominent climbing defects. In the Prkn mouse orthologue, the amino acid R274 corresponds to human R275. Here we described an age-related motor impairment and a muscle phenotype in R274W +/+ mice. In vitro, Parkin R274W mutation correlates with abnormal myoblast differentiation, mitochondrial defects, and alteration in mitochondrial mRNA and protein levels. Our data suggest that the Parkin R274W mutation may impact mitochondrial physiology and eventually myoblast proliferation and differentiation.

Association between fatigue and MDS-UPDRS in individuals with Parkinson's disease: cross-sectional study

BACKGROUND

Fatigue is significant in the context of Parkinson's disease (PD), considering that one-third of patients classify it as the most restricting symptom in their daily life activities (DLAs). The objective was to verify the relationship (association) between fatigue and non-motor and motor symptoms of PD.

METHODS

A cross-sectional study which included 100 individuals with PD. Initially, demographic and clinical data (modified Hoehn and Yahr scale-HY, anxiety, and depression) were collected. To assess the non-motor and motor symptoms of PD, the Movement Disorders Society-Unified Parkinson's Disease Rating Scale (MDS-UPDRS) was applied. Fatigue was evaluated using the Parkinson Fatigue Scale.

RESULTS

A higher HY score, greater severity of non-motor aspects of DLAs and motor aspects of DLAs, more motor complications, and higher levels of anxiety as well as depression were observed in the "fatigue" group. Fatigue was associated with a lower daily equivalent levodopa dose (LEDD), a higher body mass index (BMI), anxiety, depression, and the presence of non-motor symptoms.

CONCLUSION

Non-motor symptoms are more determining factors for fatigue than the motor condition itself, with an association between fatigue and higher BMI scores, increased anxiety and depression, lower LEDD, and greater severity of non-motor aspects of DLAs. Individuals in the "fatigue" group had higher HY scores, anxiety, and depression, worse non-motor and motor symptoms related to experiences of daily life, as well as motor complications.

Persistent fatigue in post-acute COVID syndrome is associated with altered T1 MRI texture in subcortical structures: a preliminary investigation

Post-acute COVID syndrome (PACS) is a global health concern and is often associated with debilitating symptoms. Post-COVID fatigue is a particularly frequent and troubling issue, and its underlying mechanisms remain incompletely understood. One potential contributor is micropathological injury of subcortical and brainstem structures, as has been identified in other patient populations. Texture-based analysis (TA) may be used to measure such changes in anatomical MRI data. The present study develops a methodology of voxel-wise TA mapping in subcortical and brainstem regions, which is then applied to T1-weighted MRI data from a cohort of 48 individuals who had PACS (32 with and 16 without ongoing fatigue symptoms) and 15 controls who had cold and flu-like symptoms but tested negative for COVID-19. Both groups were assessed an average of 4-5 months post-infection. There were no significant differences between PACS and control groups, but significant differences were observed within the PACS groups, between those with and without fatigue symptoms. This included reduced texture energy and increased entropy, along with reduced texture correlation, cluster shade and profile in the putamen, pallidum, thalamus and brainstem. These findings provide new insights into the neurophysiological mechanisms that underlie PACS, with altered tissue texture as a potential biomarker of this debilitating condition.

Golexanolone reduces glial activation in the striatum and improves non-motor and some motor alterations in a rat model of Parkinson's disease

Background

Parkinson's disease (PD) affects more than 6 million people worldwide. Along with motor impairments, patients and animal models exhibiting PD symptoms also experience cognitive impairment, fatigue, anxiety, and depression. Currently, there are no drugs available for PD that alter the progression of the disease. A body of evidence suggests that increased GABA levels contribute to the reduced expression of tyrosine hydroxylase (TH) and accompanying behavioral deficits. TH expression may be restored by blocking GABAA receptors. We hypothesized that golexanolone (GR3027), a well-tolerated GABAA receptor-modulating steroid antagonist (GAMSA), may improve Parkinson's symptoms in a rat model of PD.

Objectives

The aims of this study were to assess whether golexanolone can ameliorate motor and non-motor symptoms in a rat model of PD and to identify some underlying mechanisms.

Methods

We used the unilateral 6-OHDA rat model of PD. The golexanolone treatment started 4 weeks after surgery. Motor symptoms were assessed using Motorater and CatWalk tests. We also analyzed fatigue (using a treadmill test), anhedonia (via the sucrose preference test), anxiety (with an open field test), and short-term memory (using a Y maze). Glial activation and key proteins involved in PD pathogenesis were analyzed using immunohistochemistry and Western blot.

Results

Rats with PD showed motor incoordination and impaired locomotor gait, increased fatigue, anxiety, depression, and impaired short-term memory. Golexanolone treatment led to improvements in motor incoordination, certain aspects of locomotor gait, fatigue, anxiety, depression, and short-term memory. Notably, golexanolone reduced the activation of microglia and astrocytes, mitigated TH loss at 5 weeks after surgery, and prevented the increase of α-synuclein levels at 10 weeks.

Conclusions

Golexanolone may be useful in improving both motor and non-motor symptoms that adversely affect the quality of life in PD patients, such as anxiety, depression, fatigue, motor coordination, locomotor gait, and certain cognitive alterations.

ON/OFF non-motor evaluation: a new way to evaluate non-motor fluctuations in Parkinson's disease

BACKGROUND

NMF are currently poorly evaluated in therapeutic decisions. A quantification of their severity would facilitate their integration. The objective of this study was to validate an autoquestionnaire evaluating the severity of non-motor fluctuations (NMF) in Parkinson's disease (PD).

METHODS

Patients with PD were included in presurgical situation for deep brain stimulation of subthalamic nuclei. They participated in the PREDISTIM cohort (a study evaluating the predictive factors for therapeutic response of subthalamic stimulation in PD) in 17 centres in France. Our questionnaire, resulting from previous phases of development, included 11 non-motor symptoms (NMS). Their severity ranged from 0 to 10 and was assessed in OFF and then ON-Dopa to study their fluctuations.

RESULTS

310 patients were included, of whom 98.8% had NMS and 98.0% had NMF. Each NMS was significantly improved by L-Dopa (decrease in severity score ranging from 43.1% to 69.9%). Fatigue was the most frequent and most severe NMS. NMS were considered more bothersome than motor symptoms by 37.5% of patients in OFF-Dopa and 34.9% in ON-Dopa.

CONCLUSIONS

This is the first questionnaire allowing a real-time quantification of the severity of NMS and their fluctuation with levodopa. It was able to confirm and measure the effect of L-dopa and show differences according to the patients and the NMS. It differs from other questionnaires by its measurement at a precise moment of the severity of the NMS, allowing its use during pretherapeutic assessments.Our questionnaire has been validated to measure the severity of NMF. It will be able to quantify the non-motor effect of anti-parkinsonian treatments and could facilitate the integration of NMF in therapeutic decisions.

Spirituality and Influencing Factors in Parkinson's Disease: A Scoping Review

Although the effect of spirituality in chronic disease has been discussed in recent years, little is known about spirituality and spiritual beliefs in Parkinson's disease. In this scoping review, the databases PubMed, Scopus and Web of Science were searched and initially identified 914 studies. A total of nine studies satisfied the inclusion criteria. It was found age, gender, education level, emotional changes, region of onset of Parkinson's disease, severity of symptoms, quality of life, religion affiliation and acceptance of Parkinson's disease influence spirituality in people with Parkinson's disease. In this context, future studies should focus on the relationship between Parkinson's disease and spirituality.

Characterizing the Neurobiological Mechanisms of Action of Exercise and Cognitive-Behavioral Interventions for Rheumatoid Arthritis Fatigue: A Magnetic Resonance Imaging Brain Study

OBJECTIVE

Chronic fatigue is a major clinical unmet need among patients with rheumatoid arthritis (RA). Current therapies are limited to nonpharmacological interventions, such as personalized exercise programs (PEPs) and cognitive-behavioral approaches (CBAs); however, most patients still continue to report severe fatigue. To inform more effective therapies, we conducted a magnetic resonance imaging (MRI) brain study of PEPs and CBAs, nested within a randomized controlled trial (RCT), to identify their neurobiological mechanisms of fatigue reduction in RA.

METHODS

A subgroup of patients with RA (n = 90), participating in an RCT of PEPs and CBAs for fatigue, undertook a multimodal MRI brain scan following randomization to either usual care (UC) alone or in addition to PEPs and CBAs and again after the intervention (six months). Brain regional volumetric, functional, and structural connectivity indices were curated and then computed employing a causal analysis framework. The primary outcome was fatigue improvement (Chalder fatigue scale).

RESULTS

Several structural and functional connections were identified as mediators of fatigue improvement in both PEPs and CBAs compared to UC. PEPs had a more pronounced effect on functional connectivity than CBAs; however, structural connectivity between the left isthmus cingulate cortex (L-ICC) and left paracentral lobule (L-PCL) was shared, and the size of mediation effect ranked highly for both PEPs and CBAs (ßAverage = -0.46, SD 0.61; ßAverage = -0.32, SD 0.47, respectively).

CONCLUSION

The structural connection between the L-ICC and L-PCL appears to be a dominant mechanism for how both PEPs and CBAs reduce fatigue among patients with RA. This supports its potential as a substrate of fatigue neurobiology and a putative candidate for future targeting.

Transcranial brain parenchyma sonographic findings in patients with myotonic dystrophy type 1 and 2

Introduction

Myotonic dystrophy type 1 (DM1) and 2 (DM2) are genetically determined progressive muscular disorders with multisystemic affection, including brain involvement. Transcranial sonography (TCS) is a reliable diagnostic tool for the investigation of deep brain structures. We sought to evaluate TCS findings in genetically confirmed DM1 and DM2 patients, and further correlate these results with patients' clinical features.

Methods

This cross-sectional study included 163 patients (102 DM1, 61 DM2). Echogenicity of the brainstem raphe (BR) and substantia nigra (SN) as well as the diameter of the third ventricle (DTV) were assessed by TCS. Patients were evaluated using the Hamilton Depression Rating Scale, Fatigue Severity Scale and Daytime Sleepiness Scale.

Results

SN hyperechogenicity was observed in 40% of DM1 and 34% of DM2 patients. SN hypoechogenicity was detected in 17% of DM1 and 7% of DM2 patients. BR hypoechogenicity was found in 36% of DM1 and 47% of DM2 subjects. Enlarged DTV was noted in 19% of DM1 and 15% of DM2 patients. Older, weaker, depressive, and fatigued DM1 patients were more likely to have BR hypoechogenicity (p < 0.05). DTV correlated with age and disease duration in DM1 (p < 0.01). In DM2 patients SN hyperechogenicity correlated with fatigue. Excessive daytime sleepiness was associated with hypoechogenic BR (p < 0.05) and enlarged DVT (p < 0.01) in DM2 patients.

Conclusions

TCS is an easy applicable and sensitive neuroimaging technique that could offer new information regarding several brainstem structures in DM1 and DM2. This may lead to better understanding of the pathogenesis of the brain involvement in DM with possible clinical implications.

Motor cortex transcranial direct current stimulation improves non-motor symptoms in early-onset Parkinson's disease: a pilot study

Early-onset Parkinson's Disease (EOPD) demands tailored treatments. The younger age of patients might account for a higher sensitivity to transcranial direct current stimulation (tDCS) based non-invasive neuromodulation, which may raise as an integrative therapy in the field. Accordingly, here we assessed the safety and efficacy of the primary left motor cortex (M1) anodal tDCS in EOPD. Ten idiopathic EOPD patients received tDCS at 2.0 mA per 20 min for 10 days within a crossover, double-blind, sham-controlled pilot study. The outcome was evaluated by measuring changes in MDS-UPDRS part III, Non-Motor Symptoms Scale (NMSS), PD-cognitive rating scale, and PD Quality of Life Questionnaire-39 scores. We showed that anodal but not sham tDCS significantly reduced the NMSS total and "item 2" (sleep/fatigue) scores. Other parameters were not modified. No adverse events occurred. M1 anodal tDCS might thus evoke plasticity changes in cortical-subcortical circuits involved in non-motor functions, supporting the value as a therapeutic option in EOPD.

Vitamin D and Its Role on the Fatigue Mitigation: A Narrative Review

Vitamin D has historically been associated with bone metabolism. However, over the years, a growing body of evidence has emerged indicating its involvement in various physiological processes that may influence the onset of numerous pathologies (cardiovascular and neurodegenerative diseases, rheumatological diseases, fertility, cancer, diabetes, or a condition of fatigue). This narrative review investigates the current knowledge of the pathophysiological mechanisms underlying fatigue and the ways in which vitamin D is implicated in these processes. Scientific studies in the databases of PubMed, Scopus, and Web of Science were reviewed with a focus on factors that play a role in the genesis of fatigue, where the influence of vitamin D has been clearly demonstrated. The pathogenic factors of fatigue influenced by vitamin D are related to biochemical factors connected to oxidative stress and inflammatory cytokines. A role in the control of the neurotransmitters dopamine and serotonin has also been demonstrated: an imbalance in the relationship between these two neurotransmitters is linked to the genesis of fatigue. Furthermore, vitamin D is implicated in the control of voltage-gated calcium and chloride channels. Although it has been demonstrated that hypovitaminosis D is associated with numerous pathological conditions, current data on the outcomes of correcting hypovitaminosis D are conflicting. This suggests that, despite the significant involvement of vitamin D in regulating mechanisms governing fatigue, other factors could also play a role.

Naringenin, a Functional Food Component, Improves Motor and Non-Motor Symptoms in Animal Model of Parkinsonism Induced by Rotenone

Parkinson's disease (PD) and other age-related neurodegenerative ailments have a strong link to oxidative stress. Bioflavonoid naringenin has antioxidant properties. The effects of pre- and post-naringenin supplementation on a rotenone-induced PD model were examined in this work. Naringenin (50 mg/kg, p.o.) was administered to rats for two weeks before the administration of rotenone in the pre-treatment phase. In contrast, rotenone (1.5 mg/kg, s.c.) was administered for eight days before naringenin (50 mg/kg, p.o.) was supplemented for two weeks in the post-treatment phase. During behavioral investigation, the motor and non-motor signs of PD were observed. Additionally, estimation of neurochemical and biochemical parameters was also carried out. Compared to controls, rotenone treatment substantially increased oxidative stress, altered neurotransmitters, and caused motor and non-motor impairments. Rotenone-induced motor and non-motor impairments were considerably reduced by naringenin supplementation. The supplementation also increased antioxidant enzyme activities and restored the changes in neurotransmitter levels. The findings of this work strongly imply that daily consumption of flavonoids such as naringenin may have a therapeutic potential to combat PD.

Mesenchymal stromal cell biotherapy for Parkinson's disease premotor symptoms

Parkinson's disease (PD) is a neurodegenerative disorder with motor deficits due to nigrostriatal dopamine depletion and with the non-motor/premotor symptoms (NMS) such as anxiety, cognitive dysfunction, depression, hyposmia, and sleep disorders. NMS is presented in at least one-fifth of the patients with PD. With the histological information being investigated, stem cells are shown to provide neurotrophic supports and cellular replacement in the damaging brain areas under PD conditions. Pathological change of progressive PD includes degeneration and loss of dopaminergic neurons in the substantia nigra of the midbrain. The current stem cell beneficial effect addresses dopamine boost for the striatal neurons and gliovascular mechanisms as competing for validated PD drug targets. In addition, there are clinical interventions for improving the patient's NMS and targeting their autonomic dysfunction, dementia, mood disorders, or sleep problems. In our and many others' research using brain injury models, multipotent mesenchymal stromal cells demonstrate an additional and unique ability to alleviate depressive-like behaviors, independent of an accelerated motor recovery. Intranasal delivery of the stem cells is discussed for it is extensively tested in rodent animal models of neurological and psychiatric disorders. In this review, we attempt to discuss the repairing potentials of transplanted cells into parkinsonism pathological regions of motor deficits and focus on preventive and treatment effects. From new approaches in the PD biological therapy, it is believed that it can as well benefit patients against PD-NMS.

Functional connectivity modifications in monoaminergic circuits occur in fatigued MS patients treated with fampridine and amantadine

BACKGROUND

Monoaminergic network dysfunction may have a role in multiple sclerosis (MS) fatigue pathogenesis.

OBJECTIVE

To investigate modifications of fatigue severity and resting state (RS) functional connectivity (FC) in monoaminergic networks of 45 fatigued MS patients after different symptomatic treatments.

METHODS

Patients were randomly, blindly assigned to fampridine (n = 15), amantadine (n = 15) or placebo (n = 15) treatment and underwent clinical and 3T-MRI evaluations at baseline (t0) and week 4 (w4), i.e. after four weeks of treatment. Fifteen healthy controls (HC) were enrolled. Dopamine-, noradrenaline- and serotonin-related RS FC was assessed by PET-guided constrained independent component analysis.

RESULTS

At t0, MS patients showed widespread monoamine-related RS FC abnormalities. At w4, fatigue scores decreased in all groups (p = range < 0.001-0.002). Concomitantly, fampridine and amantadine patients showed increased insular RS FC in dopamine-related and noradrenaline-related networks (p < 0.001, uncorrected). Amantadine patients also showed increased RS FC of anterior cingulate cortex in dopamine-related and noradrenaline-related networks (p < 0.001, uncorrected). Placebo patients showed increased precuneus/middle cingulate RS FC in the noradrenaline-related network (p < 0.001, uncorrected). In fampridine and placebo patients, just tendencies towards correlations between RS FC and fatigue modifications were found.

CONCLUSIONS

In MS patients, specific RS FC modifications in PET-guided monoaminergic networks were observed, concomitantly with fatigue improvements following treatment.

TRIAL REGISTRATION NUMBER

EudraCT 2010-023678-38.

The Impact of Nonmotor Symptoms on Health-Related Quality of Life in Parkinson’s Disease: A Network Analysis Approach

Nonmotor symptoms negatively affect health-related quality of life (HRQoL) in patients with Parkinson’s disease (PD). However, it is unknown which nonmotor symptoms are most commonly associated with HRQoL. Considering the complex interacting network of various nonmotor symptoms and HRQoL, this study aimed to reveal the network structure, explained HRQoL variance, and identify the nonmotor symptoms that primarily affect HRQoL. We included 689 patients with PD from the Cohort of Patients with Parkinson’s Disease in Spain (COPPADIS) study who were rated on the Nonmotor Symptoms Scale in Parkinson’s disease (NMSS) and the Parkinson´s Disease Questionnaire 39 (PDQ-39) at baseline. Network analyses were performed for the 30 items of the NMSS and both the PDQ-39 summary index and eight subscales. The nodewise predictability, edge weights, strength centrality, and bridge strength were determined. In PD, nonmotor symptoms are closely associated with the mobility, emotional well-being, cognition, and bodily discomfort subscales of the PDQ-39. The most influential nonmotor symptoms were found to be fatigue, feeling sad, hyperhidrosis, impaired concentration, and daytime sleepiness. Further research is needed to confirm whether influencing these non-motor symptoms can improve HRQoL.

Orthostatic Hypotension Is a Predictor of Fatigue in Drug-Naïve Parkinson's Disease

Introduction

Fatigue and orthostatic hypotension (OH) are common and disabling nonmotor symptoms (NMSs) of Parkinson's disease (PD), but none of the studies have reported on the longitudinal association between fatigue and OH.

Methods

Drug-naïve PD patients were recruited from a hospital-based cohort and evaluated with the Parkinson Fatigue Scale (PFS), head-up tilt test, Unified PD Rating Scale, Hoehn and Yahr stage, Montreal Cognitive Assessment, Scale for Outcomes in PD-Autonomic (SCOPA-AUT), Beck Depression Inventory (BDI), Beck Anxiety Inventory, PD Sleep Scale, and medications at the baseline and follow-up visits.

Results

A total of 80 patients were included, and the mean ages were 66.6 and 63.8 years in the fatigue and nonfatigue groups, respectively. The prevalence of fatigue was 17.5% (14/80) at the baseline and follow-up (mean follow-up: 23.3 ± 9.9 months). The prevalence of OH in the fatigue group was 57.1%, and it was significantly higher than that of the nonfatigue group. Six of the 14 patients (42.9%) in the fatigue group had persistent fatigue at the follow-up, and eight of them (57.1%) converted to the nonfatigue group. Logistic regression analysis demonstrated that the changes of BDI and the presence of OH at the baseline were the predictors for fatigue in drug-naïve PD.

Conclusion

Fatigue is a common NMS in PD but can vary depending on the disease course. OH and depression are the most relevant predictors for the development of fatigue in drug-naïve PD. The present study suggests that the management of autonomic symptoms and depression might be helpful for managing fatigue in PD.

Physical Exercise as a Potential Treatment for Fatigue in Parkinson's Disease? A Systematic Review and Meta-Analysis of Pharmacological and Non-Pharmacological Interventions

BACKGROUND

Fatigue is one of the most common and debilitating non-motor symptoms among patients with Parkinson's disease (PD) and significantly impacts quality of life. Therefore, effective treatment options are needed.

OBJECTIVE

To provide an update on randomized controlled trials (RCTs) including pharmacological and non-pharmacological (but non-surgical) treatments that examine the effects of fatigue on PD patients.

METHODS

We searched the MEDLINE, EMBASE, PsycINFO, CENTRAL, and CINAHL databases for (cross-over) RCTs on pharmacological and non-pharmacological interventions for treating fatigue in PD patients until May 2021. Meta-analyses for random-effects models were calculated when two or more studies on the same treatment option were available using standardized mean differences (SMDs) with 95% confidence intervals (CIs).

RESULTS

Fourteen pharmacological and 16 non-pharmacological intervention RCTs were identified. For pharmacological approaches, a meta-analysis could only be performed for modafinil compared to placebo (n = 2) revealing a non-significant effect on fatigue (SMD = - 0.21, 95% CI - 0.74-0.31, p = 0.43). Regarding non-pharmacological approaches, physical exercise (n = 8) following different training approaches versus passive or placebo control groups showed a small significant effect (SMD = - 0.37, 95% CI - 0.69- - 0.05, p = 0.02) which could not be demonstrated for acupuncture vs. sham-acupuncture (SMD = 0.16, 95% CI - 0.19-0.50, p = 0.37).

CONCLUSION

Physical exercise may be a promising strategy to treat fatigue in PD patients. Further research is required to examine the efficacy of this treatment strategy and further interventions. Future studies should differentiate treatment effects on physical and mental fatigue as the different underlying mechanisms of these symptoms may lead to different treatment responses. More effort is required to develop, evaluate, and implement holistic fatigue management strategies for PD patients.

Survival in patients with Parkinson's disease: a ten-year follow-up study in northern China

BACKGROUND

A thorough understanding of the factors that influence patient survival in Parkinson's disease (PD) will aid in prognosis prediction and provide a new direction for disease modification treatment. Currently, there are no standardized mortality ratio (SMR) data for PD patients in the northern Chinese mainland. The main focus of this study was to determine which factors in the prospectively collected baseline characteristics can affect the survival of PD patients. In addition, for the first time, we investigated the SMR of PD patients in northern China.

METHODS

Between 2009 and 2012, 218 PD patients were continuously recruited from the movement disorder clinic of the First Affiliated Hospital of Dalian Medical University and followed up until death or May 31, 2021. The prespecified prognostic variables were demographics, clinical features, lifestyle factors, and drug dose prospectively collected at baseline. To determine the independent predictors of survival during follow-up, the Cox proportional hazards model was used. Kaplan-Meier analysis was applied to estimate the overall survival curve and to compare survival between layers based on statistically significant predictors. The SMR of this northern Chinese mainland PD cohort was calculated.

RESULTS

After a mean follow-up of 9.58 ± 2.27 years, 50 patients (22.90%) died. Factors that could individually predict shortened survival during follow-up included older age at onset (hazard ratio [HR] 1.10, 95% confidence interval [CI] 1.06-1.15), Hoehn and Yahr (H&Y) stage ≥ 3 (HR 9.36, 95% CI 2.82-31.03) and severe cognitive impairment (HR 6.18, 95% CI 2.75-13.88). Univariate Cox regression revealed that a certain amount of physical activity was associated with better survival (HR 0.41, 95% CI 0.22-0.74), while fatigue was associated with an increased risk of death (HR 2.54, 95% CI 1.37-4.70). The overall SMR was 1.32 (95% CI 0.98-1.74).

CONCLUSIONS

Older age at onset, higher baseline H&Y stage, and severe cognitive impairment have a negative impact on survival. The 10-year survival of PD patients is not significantly different from that of the general population in China.

Perception of Physical Demand, Mental Demand, and Performance: A Comparison of Two Voice Interventions for Parkinson's Disease

PURPOSE

The purpose of the study was to examine the effect of two voice intervention approaches for hypophonia secondary to Parkinson's disease (PD) on self-reported measures of physical demand, mental demand, and vocal performance.

METHOD

Thirty-four persons with hypophonia secondary to PD were assigned to one of three groups: Lee Silverman Voice Treatment (LSVT) LOUD (n = 12), SpeechVive (n = 12), and nontreatment clinical control (n = 10). The LSVT LOUD and the SpeechVive participants received 8 weeks of voice intervention following the standardized protocol previously described for each approach. To confirm the effectiveness of each voice intervention, sound pressure level (dB SPL) data were analyzed for the experimental and control participants for a monologue sample obtained pretreatment, midtreatment, and posttreatment. During the voice intervention period, the LSVT LOUD and the SpeechVive participants were instructed to complete a modified version of the National Aeronautics and Space Administration Task Load Index rating scale to indicate the mental and physical demand required to complete the intervention activities, and to indicate how well they performed in completing the assigned vocal tasks.

RESULTS

The LSVT LOUD and the SpeechVive participants demonstrated a significant posttreatment increase in SPL (dB), in comparison to the clinical controls, thus confirming a positive intervention effect. The LSVT LOUD participants reported significantly higher ratings of physical and mental demand over the course of treatment, in comparison to the SpeechVive participants.

CONCLUSION

Consideration of the mental and physical demand associated with two voice intervention approaches, commonly used for PD, may help to foster improved therapeutic compliance and treatment outcomes.

Poor sleep quality is associated with fatigue and depression in early Parkinson's disease: A longitudinal study in the PALS cohort

Background

Sleep disorders are common in Parkinson's disease (PD). However, the longitudinal relationship between sleep quality and the other non-motor symptoms of PD has not been well characterized, especially in early PD.

Objective

To explore the value of baseline sleep quality in predicting the progression of other non-motor symptoms in early PD.

Methods

109 early PD patients were recruited to the study. Patients were stratified into good and poor sleepers using the Pittsburgh Sleep Quality Index (PSQI). Assessments performed at baseline and 1 year follow-up included the Epworth Sleepiness Scale, Fatigue Severity Scale, Non-Motor Symptom Scale, Geriatric Depression Scale, Hospital Anxiety and Depression Scale, Apathy Scale, Montreal Cognitive Assessment and detailed neuropsychological assessments. Multivariable linear regression was performed at baseline to investigate differences in clinical scores between poor and good sleepers, while multivariable regression models were used to investigate associations between sleep quality and progression of test scores at 1 year follow-up.

Results

59 poor sleepers and 50 good sleepers were identified. At baseline, poor sleepers had greater HADS anxiety scores (p = 0.013) [2.99 (95% CI 2.26, 3.73)] than good sleepers [1.59 (95% CI 0.75, 2.42)]. After 1 year, poor sleepers had greater fatigue (FSS scores +3.60 as compared to −2.93 in good sleepers, p = 0.007) and depression (GDS scores +0.42 as compared to −0.70, p = 0.006).

Conclusion

This study shows a longitudinal association between sleep quality, fatigue, and depression in early PD patients, independent of medication effect and disease severity, this may support the hypothesis that a common serotonergic pathway is implicated in these non-motor symptoms.

Fatigue in Brazilian patients with Parkinson's disease

Fatigue is a non-motor symptom of high prevalence in Parkinson’s disease (PD); however, it is still unknown and neglected by health professionals.

Effects of Lower Limb Cycling Training on Different Components of Force and Fatigue in Individuals With Parkinson’s Disease

The strength of lower extremity is important for individuals to maintain balance and ambulation functions. The previous studies showed that individuals with Parkinson’s disease suffered from fatigue and strength loss of central origin. The purpose of this study was to investigate the effect of lower extremities’ cycling training on different components of force and fatigue in individuals with Parkinson’s disease. Twenty-four individuals (13 males, 11 females, mean age: 60.58 ± 8.21 years) diagnosed with idiopathic Parkinson’s disease were randomized into training and control groups. The maximum voluntary contraction (MVC) force, voluntary activation level (VA), and twitch force of knee extensors were measured using a custom-made system with surface electrical stimulation. The general, central, and peripheral fatigue indexes (GFI, CFI, and PFI) were calculated after a fatiguing cycling protocol. Subjects received 8 weeks of low resistance cycling training (training group) or self-stretching (control group) programs. Results showed that MVC, VA, and twitch force improved (p < 0.05) only in the training group. Compared to the baseline, central fatigue significantly improved in the training group, whereas peripheral fatigue showed no significant difference in two groups. The cycling training was beneficial for individuals with Parkinson’s disease not only in muscle strengthening but also in central fatigue alleviation. Further in-depth investigation is required to confirm the effect of training and its mechanism on central fatigue.

Evidence that Neuromuscular Fatigue Is not a Dogma in Patients with Parkinson's Disease

PURPOSE

Given the increased level of fatigue frequently reported by patients with Parkinson's disease (PD), this study investigated the interaction between central and peripheral components of neuromuscular fatigue (NF) in this population compared with healthy peers.

METHODS

Changes in maximal voluntary activation (ΔVA, central fatigue) and potentiated twitch force (ΔQtw,pot, peripheral fatigue) pre-post exercise were determined via the interpolated twitch technique in 10 patients with PD and 10 healthy controls (CTRL) matched for age, sex, and physical activity. Pulmonary gas exchange, femoral blood flow, and quadriceps EMG were measured during a fatiguing exercise (85% of peak power output [PPO]). For a specific comparison, on another day, CTRL repeat the fatiguing test matching the time to failure (TTF) and PPO of PD.

RESULTS

At 85% of PPO (PD, 21 ± 7 W; CTRL, 37 ± 22 W), both groups have similar TTF (~5.9 min), pulmonary gas exchange, femoral blood flow, and EMG. After this exercise, the maximal voluntary contraction (MVC) force and Qtwpot decreased equally in both groups (-16%, P = 0.483; -43%, P = 0.932), whereas VA decreased in PD compared with CTRL (-3.8% vs -1.1%, P = 0.040). At the same PPO and TTF of PD (21 W; 5.4 min), CTRL showed a constant drop in MVC, and Qtwpot (-14%, P = 0.854; -39%, P = 0.540), instead VA decreased more in PD than in CTRL (-3.8% vs -0.7%, P = 0.028).

CONCLUSIONS

In PD, central NF seems exacerbated by the fatiguing task which, however, does not alter peripheral fatigue. This, besides the TTF like CTRL, suggests that physical activity may limit NF and counterbalance PD-induced degeneration through peripheral adaptations.

Data-Driven Prediction of Fatigue in Parkinson's Disease Patients

Introduction: Numerous non-motor symptoms are associated with Parkinson's disease (PD) including fatigue. The challenge in the clinic is to detect relevant non-motor symptoms while keeping patient-burden of questionnaires low and to take potential subgroups such as sex differences into account. The Fatigue Severity Scale (FSS) effectively detects clinically significant fatigue in PD patients. Machine learning techniques can determine which FSS items best predict clinically significant fatigue yet the choice of technique is crucial as it determines the stability of results. Methods: 182 records of PD patients were analyzed with two machine learning algorithms: random forest (RF) and Boruta. RF and Boruta calculated feature importance scores, which measured how much impact an FSS item had in predicting clinically significant fatigue. Items with the highest feature importance scores were the best predictors. Principal components analysis (PCA) grouped highly related FSS items together. Results: RF, Boruta and PCA demonstrated that items 8 ("Fatigue is among my three most disabling symptoms") and 9 ("Fatigue interferes with my work, family or social life") were the most important predictors. Item 5 ("Fatigue causes frequent problems for me") was an important predictor for females, and item 6 ("My fatigue prevents sustained physical functioning") was important for males. Feature importance scores' standard deviations were large for RF (14-66%) but small for Boruta (0-5%). Conclusion: The clinically most informative questions may be how disabling fatigue is compared to other symptoms and interference with work, family and friends. There may be some sex-related differences with frequency of fatigue-related complaints in females and endurance-related complaints in males yielding significant information. Boruta but not RF yielded stable results and might be a better tool to determine the most relevant components of abbreviated questionnaires. Further research in this area would be beneficial in order to replicate these findings with other machine learning algorithms, and using a more representative sample of PD patients.

Understanding fatigue in progressive supranuclear palsy

Fatigue is a common and disabling non-motor symptom (NMS) of Parkinson's disease (PD); however, it has been poorly understood in patients with progressive supranuclear palsy (PSP). We investigated the association between fatigue, clinical features, and other NMS in patients with probable PSP. In 72 probable PSP patients, fatigue was investigated using the Parkinson Fatigue Scale (PFS). Further, all patients were evaluated using the PSP rating scale (PSPRS), Beck Depression Inventory (BDI), Mini-Mental State Examination (MMSE), Frontal Assessment Battery (FAB), PD Sleep Scale (PDSS), NMS scale (NMSS), PD Questionnaire-39 summary index (PDQ-39 SI), and Scale for outcomes in PD-Autonomic (SCOPA-AUT). The prevalence of fatigue assessed by PFS was 38.9% (28/72) in patients with PSP. The secondary fatigue was defined as fatigued patients with depression and/or sleep disturbances. We divided the patients into primary (n = 15), secondary (n = 13), and non-fatigue groups. There were no differences in age, sex, disease duration, and PSPRS, PDSS, MMSE, and FAB scores among the three groups. The primary fatigue group had higher scores in PDQ-39 SI compared to the non-fatigue group. The secondary fatigue group showed higher scores in NMSS, PDQ-39 SI, and SCOPA-AUT compared to the non-fatigue group. PFS was positively correlated with NMSS and PDQ-39 SI and SCOPA-AUT. Fatigue is common in patients with PSP and is associated with the NMS and the quality of life in these patients. The present study provides meaningful insight into fatigue in patients with PSP.

Association between Fatigue and Hoehn-Yahr Staging in Parkinson's Disease: Eight-Year Follow-Up Study

The severity of Parkinson's disease (PD) is developed by multifactorial factors. Falls can worsen disease severity. We previously found that frontal assessment battery (FAB) score was associated with a higher risk of future falls. This eight-year follow-up study aimed to verify whether factors including low FAB score can be the risk of PD progression based on the Hoehn and Yahr scale. In total, 95 patients were initially enrolled in this research and 45 were included in the final follow-up. Then, the cohort was classified into patients with and without disease progression, defined by upgrade of Hoehn-Yahr stage. Differences in clinical characteristics between patients with disease progression and those without were evaluated using the Mann-Whitney U test. Eighteen independent variables were evaluated via a univariate logistic regression analysis. Of the 45 patients enrolled, 32 had disease progression and 13 had no progression. Age (p = 0.033), BFI score (p = 0.003), Zung self-rating depression (p = 0.011), and anxiety scale (p = 0.026) were significantly increased in patients who had disease progression than those with no disease progression. On multivariate logistic regression analysis, brief fatigue inventory (BFI) score (OR = 1.048, p = 0.045, 95% CI = 1.001-1.098) was significantly related to disease progression. All BFI subscores related to general fatigue. Fatigue could predict the progression of motor dysfunction severity over a longitudinal duration in patients with PD with disease progression, having declining physical and mental fatigue.

Frontal Transcranial Direct Current Stimulation as a Potential Treatment of Parkinson's Disease-Related Fatigue

In contrast to motor symptoms, non-motor symptoms in Parkinson’s disease (PD) are often poorly recognized and inadequately treated. Fatigue is one of the most common non-motor symptoms in PD and affects a broad range of everyday activities, causes disability, and substantially reduces the quality of life. It occurs at every stage of PD, and once present, it often persists and worsens over time. PD patients attending the 2013 World Parkinson Congress voted fatigue as the leading symptom in need of further research. However, despite its clinical significance, little progress has been made in understanding the causes of Parkinson’s disease-related fatigue (PDRF) and developing effective treatment options, which argues strongly for a greater effort. Transcranial direct current stimulation (tDCS) is a technique to non-invasively modulate cortical excitability by delivering low electrical currents to the cerebral cortex. In the past, it has been consistently evidenced that tDCS has the ability to induce neuromodulatory changes in the motor, sensory, and cognitive domains. Importantly, recent data present tDCS over the frontal cortex as an effective therapeutic option to treat fatigue in patients suffering from multiple sclerosis (MS). The current opinion paper reviews recent data on PDRF and the application of tDCS for the treatment of fatigue in neuropsychiatric disorders to further develop an idea of using frontal anodal tDCS as a potential therapeutic strategy to alleviate one of the most common and severe non-motor symptoms of PD.

Merging Yoga and Occupational Therapy for Parkinson’s Disease improves fatigue management and activity and participation measures

Introduction

The purpose of this study was to explore the influence of a falls-risk management intervention, Merging Yoga and Occupational Therapy for Parkinson’s Disease, on fatigue and activity and participation measures, as well as examine the relationship between these constructs.

Methods

This mixed methods study included 17 participants with Parkinson’s disease. Participants took the Modified Fatigue Impact Scale and the International Classification of Functioning, Disability, and Health Measure of Participation and Activities Screener at three 8-week intervals: baseline (followed by an 8-week control period), pre-intervention, and post-intervention. Focus groups were completed at the conclusion of the study to explore participants’ perception of Merging Yoga and Occupational Therapy for Parkinson’s Disease related to their fatigue and activity and participation.

Results

Fatigue and activity and participation measures were significantly correlated ( r = 0.76). Activity and participation measures (Measure of Participation and Activities Screener) significantly improved after the intervention ( p = 0.012). Four themes related to fatigue and/or activity and participation emerged following qualitative analysis, including: managing fatigue: paying attention and acting accordingly; creating mindfulness in daily activities; giving and receiving within a community; and strengthening relationship to self and others.

Conclusion

Participants experienced improvement in activity and participation measures and perceived fatigue management after engagement in the community-based Merging Yoga and Occupational Therapy for Parkinson’s Disease program.

Parkinson's disease in women: Mechanisms underlying sex differences

Parkinson's disease is a neurodegenerative disease which is associated with different motor, cognitive and mood-related problems. Though it has been established that Parkinson's disease is less prevalent in women in comparison to men, the differences tend to diminish with the advancing age. Different genetic, hormonal, neuroendocrinal and molecular players contribute towards the differences in the Parkinson's disease pathogenesis. Furthermore, data available with respect to the therapeutic management of Parkinson's disease in females is limited; women often tend to suffer more from the side effects of the currently available drugs. The present review highlights the sex-specific differences which play a role in the manifestation of these symptoms and side effects of the currently available therapeutic strategies. We have also discussed the current and upcoming therapeutic strategies which are in the clinical trials such as adenosine 2A (A2A) receptor antagonists, estrogen replacement therapy, α-synuclein targeting vaccines and antibodies, Botulinum toxin A, Fas-associated factor-1 (FAF-1) inhibitors, thiazolidinediones, 5-HT1_A receptor agonists, dopamine D1/D5 receptor agonists, Glucagon-like peptide 1 (GLP-1) analogues and certain plant based principles for the treatment of Parkinson's disease in women.

Lower Urinary Tract and Gastrointestinal Dysfunction Are Common in Early Parkinson's Disease

Purpose

Autonomic dysfunction is a common nonmotor feature and early manifestation of Parkinsons disease (PD). Autonomic dysfunction in PD is associated with a worse prognosis. We sought to characterize autonomic dysfunction and identify associated factors in patients with early PD.

Methods

An observational, cross-sectional, descriptive, and analytical study was conducted to evaluate patients with early PD from the Parkinsons Progression Markers Initiative. We utilized the Scales for Outcomes in Parkinsons Disease-Autonomic dysfunction questionnaire to determine the prevalence and frequencies of autonomic symptomatology. The cohort was grouped into high and low dysautonomic scores. A regression model identified variables that independently explained dysautonomic scores in our early PD cohort.

Results

414 PD patients had a mean age of 61.1 (SD 9.7) years at diagnosis and mean disease duration of 6.7 (SD 6.6) months. Among all patients, 43.7% (181/414) had high dysautonomic scores. Urinary and gastrointestinal symptoms were the most prevalent and frequently reported dysautonomic symptoms. Patients with fatigue (beta = 4.28, p < 0.001), probable rapid eye movement sleep behavior disorder (beta = 2.71, p < 0.001), excessive daytime sleepiness (beta = 1.88,p=0.039), impulsivity and compulsivity (beta = 2.42, p < 0.001), and increasing age (beta = 1.05, p < 0.001) were more likely to have high dysautonomic scores.

Conclusion

Lower urinary tract and gastrointestinal symptoms are prevalent and frequent in early PD patients. Fatigue, sleep disorders, impulsivity and compulsivity, and age are predictors of autonomic dysfunction. Autonomic symptoms predominated in this group of early PD patients in the disease course and were associated with more severe disease.

Parkinson's Disease EMG Data Augmentation and Simulation with DCGANs and Style Transfer

This paper proposes two new data augmentation approaches based on Deep Convolutional Generative Adversarial Networks (DCGANs) and Style Transfer for augmenting Parkinson’s Disease (PD) electromyography (EMG) signals. The experimental results indicate that the proposed models can adapt to different frequencies and amplitudes of tremor, simulating each patient’s tremor patterns and extending them to different sets of movement protocols. Therefore, one could use these models for extending the existing patient dataset and generating tremor simulations for validating treatment approaches on different movement scenarios.

Massage therapy as a complementary treatment for Parkinson's disease: A Systematic Literature Review

OBJECTIVE

There is no definite cure for Parkinson's disease (PD); therefore, the goals for symptomatic treatment are to improve quality of life and manage the motor and non-motor symptoms of the disease. Although massage is the one of the commonest used forms of complementary and alternative medicine (CAM), there is no systematically-oriented review focusing specifically on the efficacy of the different massage techniques on PD.Aim of this review was to evaluate the quality of evidence referring to massage therapy for PD.

DESIGN

A systematic search was conductedin the MEDLINE database to identify the efficacy of massage on PD between 01/01/1970 and 06/12/2019.

RESULTS

A total of 12 studies were analyzed in this systematic review. Massage therapy seems to induce relaxation in most cases, which is accompanied by biological measures involving urine stress hormones. Quality of life has been shown to be improved upon various therapeutic massage styles, involving classical whole-body therapeutic massage and reflexology. Non-motor symptoms, such as sleep disturbances, pain, fatigue, anxiety and depressive symptoms have been demonstrated to be improved upon different massage techniques, including classical deep therapeutic massage, Traditional Japanese (Anma) massage, Thai massage, neuromuscular therapy and Yin Tui Na massage. Regarding motor symptoms, classical therapeutic massage, Traditional Japanese (Anma) massage, Thai massage, and neuromuscular therapy seemed to improve motor symptoms, whereas Yin Tui Na technique combined with acupuncture was associated with worse motor scores.

CONCLUSIONS

Despite the methodological concerns regarding the existing evidence, there is a wide range of safe massage techniques with beneficial effects on both motor and non-motor symptoms of PD. Longitudinal studies are needed to justify the introduction of massage therapy into clinical practice.

EEG Microstates Change in Response to Increase in Dopaminergic Stimulation in Typical Parkinson's Disease Patients

Objectives: Characterizing pharmacological response in Parkinson's Disease (PD) patients may be a challenge in early stages but gives valuable clues for diagnosis. Neurotropic drugs may modulate Electroencephalography (EEG) microstates (MS). We investigated EEG-MS default-mode network changes in response to dopaminergic stimulation in PD. Methods: Fourteen PD subjects in HY stage III or less were included, and twenty-one healthy controls. All patients were receiving dopaminergic stimulation with levodopa or dopaminergic agonists. Resting EEG activity was recorded before the first daily PD medication dose and 1 h after drug intake resting EEG activity was again recorded. Time and frequency variables for each MS were calculated. Results: Parkinson's disease subjects MS A duration decreases after levodopa intake, MS B appears more often than before levodopa intake. MS E was not present, but MS G was. There were no significant differences between control subjects and patients after medication intake. Conclusion: Clinical response to dopaminergic drugs in PD is characterized by clear changes in MS profile. Significance: This work demonstrates that there are clear EEG MS markers of PD dopaminergic stimulation state. The characterization of the disease and its response to dopaminergic medication may be of help for early therapeutic diagnosis.

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.

Nonmotor Subtyping in Parkinson's Disease

Nonmotor symptoms are integral to Parkinson's disease. Several subtypes dominated by specific nonmotor symptoms have emerged. In this chapter, the rationale behind nonmotor subtyping and currently proposed nonmotor subgroups within Parkinson's disease based on data-driven cluster analysis and clinical observations will be summarized. Furthermore, the concept of seven clinical nonmotor subtypes will be discussed in detail including the clinical presentation, potential biomarkers, and the clinical relevance. In future, nonmotor subtypes will possibly play a major role within the aim to achieve personalized medicine.

Prolonged Walking with a Wearable System Providing Intelligent Auditory Input in People with Parkinson's Disease

Rhythmic auditory cueing is a well-accepted tool for gait rehabilitation in Parkinson's disease (PD), which can now be applied in a performance-adapted fashion due to technological advance. This study investigated the immediate differences on gait during a prolonged, 30 min, walk with performance-adapted (intelligent) auditory cueing and verbal feedback provided by a wearable sensor-based system as alternatives for traditional cueing. Additionally, potential effects on self-perceived fatigue were assessed. Twenty-eight people with PD and 13 age-matched healthy elderly (HE) performed four 30 min walks with a wearable cue and feedback system. In randomized order, participants received: (1) continuous auditory cueing; (2) intelligent cueing (10 metronome beats triggered by a deviating walking rhythm); (3) intelligent feedback (verbal instructions triggered by a deviating walking rhythm); and (4) no external input. Fatigue was self-scored at rest and after walking during each session. The results showed that while HE were able to maintain cadence for 30 min during all conditions, cadence in PD significantly declined without input. With continuous cueing and intelligent feedback people with PD were able to maintain cadence (p = 0.04), although they were more physically fatigued than HE. Furthermore, cadence deviated significantly more in people with PD than in HE without input and particularly with intelligent feedback (both: p = 0.04). In PD, continuous and intelligent cueing induced significantly less deviations of cadence (p = 0.006). Altogether, this suggests that intelligent cueing is a suitable alternative for the continuous mode during prolonged walking in PD, as it induced similar effects on gait without generating levels of fatigue beyond that of HE.