Exacerbated physical fatigue and mental fatigue in Parkinson's disease

Postural control of prolonged standing in people with Parkinson's disease

People with Parkinson's disease (pwPD) have reduced adaptability to postural control during prolonged standing compared to neurologically healthy individuals (control). Objective. The study aimed to characterize postural changes during prolonged standing and their effect on postural control in pwPD compared to control. We recorded the body sway of the second lumbar vertebra of 23 pwPD and 23 control while they performed prolonged standing (15 min). The number and amplitude of the body sway patterns (shifts, fidgets, and drifts), the root mean square, velocity, and frequency of the body sway were analyzed. The number of shifts in the anterior-posterior (AP) and medial-lateral (ML) directions was greater for the pwPD than the control. In addition, the amplitudes of shifts in the AP direction and fidgets in the AP and ML directions were greater for the pwPD than the control. Our results show that: (1) A larger number of shifts of body sway suggest references positions are frequently changing; (2) Fidgets is a pumping mechanism and can be sensory-demand action to restore mechanoreceptors activity on the foot sole; and (3) No drift changes may suggest there is no slow migration of reference position. We conclude that pwPD exhibits different behavior than healthy ones during prolonged standing, suggesting that prolonged standing could distinguish individuals with Parkinson's disease.

Post-stroke fatigue: a review of development, prevalence, predisposing factors, measurements, and treatments

Background

Post-stroke fatigue (PSF) is a ubiquitous and overwhelming symptom for most stroke survivors. However, there are no effective management strategies for PSF, which is partly due to our limited understanding.

Objective

In this paper, we review the development, prevalence, predisposing factors, measurements, and treatments of PSF.

Results

PSF is an independent symptom after stroke, with a prevalence ranging from 42 to 53%, which depends on the selection of measurement tools and stroke characteristics. It is affected by biological, physical, and psychological factors, among which inflammation may play a key role.

Conclusion

Numerous but non-specific evaluation measurement tools limit the management of PSF. In clinical practice, it may be beneficial to identify PSF by combining scales and objective indexes, such as walking tests and electromyographic examinations. There are no evidence-based interventions to improve PSF. However, increasing evidence suggests that transcranial direct-current stimulation and mindfulness-based interventions may become promising treatments. Further studies are urgently needed to better understand the etiology of PSF, thereby providing the basis for developing new measurement tools and targeted treatments.

Self- and observer ratings of capacity limitations in patients with neurological conditions

OBJECTIVE

The purpose of this study was to compare the self- and observer ratings of capacity limitations in patients with neurological conditions. Research on this topic is relevant for assessing the patients' ability to participate in work and social life and improving collaborative patient-clinician relationships.

METHOD

The self- and observer ratings of capacity limitations in a sample of N = 245 patients with neurological conditions from a rehabilitation facility were compared and assessed using the short rating of activity limitations and participation restrictions in mental disorders according to the International Classification of Functioning, Disability and Health (Mini-ICF-APP) and the equivalent self-rating questionnaire (Mini-ICF-APP-S).

RESULTS

Paired-samples t-tests revealed significant differences between the self- and observer ratings for six out of 13 capacity dimensions. On average, the patients rated the capacity dimensions adherence to regulations, planning and structuring of tasks, professional competency and endurance as significantly less limited, in comparison to the observers (small to medium effect sizes). The self-ratings for limitation of contact with others and self-care were only marginally higher than the observer ratings.

CONCLUSIONS

The findings show that psychological capacity limitations occur in patients with neurological conditions. In clinical practice, limitations in each capacity dimension and discrepancies in patient- and clinician-ratings should be thoroughly assessed. This is especially relevant in patients with neurological conditions who have a potential tendency to underestimate or deny their disability.

Pharmacological and Behavioral Interventions for Fatigue in Parkinson's Disease: A Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

This study aims to evaluate pharmacological and behavioral interventions for the treatment of fatigue in Parkinson's disease (PD) patients.

METHODS

We systematically searched PubMed, PsycINFO, Web of Science, EMBASE, CNKI, Wan fang, and VIP up to July 31, 2022. We used Revman 5.3 software for the meta-analysis. The outcomes included Fatigue Severity Scale (FSS) and Parkinson's Fatigue Scale (PFS). The mean difference (MD) and 95% confidence intervals (CI) were collected or calculated.

RESULTS

Thirteen randomized controlled trials (RCTs) with a total of 1758 patients were included. The meta-analysis showed that current clinical treatments reduced FSS (MD: -1.60, 95% CI: -3.14 to -0.05) and PFS (MD: -0.61, 95% CI: -1.17 to -0.05) in patients with PD. Subgroup meta-analysis showed that: (1) neither pharmacological interventions nor behavioral interventions reduced FSS in PD patients; (2) dopaminergic drugs dose-dependently significantly reduced the PFS in patients with PD; (3) behavioral interventions have an almost significant effect (MD: -6.69, 95% CI: -13.71 to 0.33, P = 0.06, I2 = 74%) on alleviating PFS in PD patients; (4) vestibular rehabilitation training significantly reduced the PFS in patients with PD.

CONCLUSIONS

Current clinical treatments alleviate fatigue in PD patients. Dopaminergic drugs may act a stronger effect than amphetamines. Behavioral interventions, especially vestibular rehabilitation training, may be a promising way for the treatment of fatigue in patients with PD though further evidence is still needed.

Understanding mental fatigue and its detection: a comparative analysis of assessments and tools

Mental fatigue has shown to be one of the root causes of decreased productivity and overall cognitive performance, by decreasing an individual's ability to inhibit responses, process information and concentrate. The effects of mental fatigue have led to occupational errors and motorway accidents. Early detection of mental fatigue can prevent the escalation of symptoms that may lead to chronic fatigue syndrome and other disorders. To date, in clinical settings, the assessment of mental fatigue and stress is done through self-reported questionnaires. The validity of these questionnaires is questionable, as they are highly subjective measurement tools and are not immune to response biases. This review examines the wider presence of mental fatigue in the general population and critically compares its various detection techniques (i.e., self-reporting questionnaires, heart rate variability, salivary cortisol levels, electroencephalogram, and saccadic eye movements). The ability of these detection tools to assess inhibition responses (which are sensitive enough to be manifested in a fatigue state) is specifically evaluated for a reliable marker in identifying mentally fatigued individuals. In laboratory settings, antisaccade tasks have been long used to assess inhibitory control and this technique can potentially serve as the most promising assessment tool to objectively detect mental fatigue. However, more studies need to be conducted in the future to validate and correlate this assessment with other existing measures of mental fatigue detection. This review is intended for, but not limited to, mental health professionals, digital health scientists, vision researchers, and behavioral scientists.

Validity and Reliability of the Fatigue Severity Scale in a Real-World Interstitial Lung Disease Cohort

Rationale: Fatigue is a common and debilitating symptom for people living with interstitial lung disease (ILD). Studies on fatigue in ILD are limited, and little headway has been made toward developing interventions targeting the alleviation of fatigue. A barrier to progress is a lack of knowledge around the performance characteristics of a patient-reported outcome measure to assess fatigue in patients with ILD. Objectives: To assess the validity and reliability of the Fatigue Severity Scale (FSS) for measuring fatigue in a national cohort of patients with ILD. Methods: FSS scores and several anchors were measured in 1,881 patients from the Pulmonary Fibrosis Foundation Patient Registry. Anchors included the Short Form 6D Health Utility Index (SF-6D) score and a single vitality question from the SF-6D; the University of California, San Diego, Shortness of Breath Questionnaire; FVC; DlCO; and 6-minute-walk distance. Internal consistency reliability, concurrent validity, and known-groups validity were assessed. Structural validity was assessed using confirmatory factor analysis. Measurements and Main Results: The FSS demonstrated high internal consistency (Cronbach's α = 0.96). There were moderate to strong correlations between FSS score and patient-reported anchors (vitality question from the SF-6D [r = 0.55] and University of California, San Diego, Shortness of Breath Questionnaire total score [r = 0.70]) and weak correlations between FSS score and physiological measures (FVC [r = -0.24], percentage predicted DlCO [r = -0.23], and 6-minute-walk distance [r = -0.29]). Higher mean FSS scores, indicating greater fatigue, were observed among patients using supplemental oxygen, those prescribed steroids, and those with lower percentage predicted FVC and percentage predicted DlCO. The confirmatory factor analysis results suggest that the nine questions of the FSS reflect one dimension of fatigue. Conclusions: Fatigue is an important patient-centered outcome in ILD that is poorly correlated with physiological measures of disease severity, including lung function and walk distance. These findings further support the need for a reliable and valid measure of patient-reported fatigue in ILD. The FSS possesses acceptable performance characteristics for assessing fatigue and distinguishing different degrees of fatigue among patients with ILD.

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.

Detection of Mental Fatigue in the General Population: Feasibility Study of Keystroke Dynamics as a Real-world Biomarker

Background

Mental fatigue is a common and potentially debilitating state that can affect individuals’ health and quality of life. In some cases, its manifestation can precede or mask early signs of other serious mental or physiological conditions. Detecting and assessing mental fatigue can be challenging nowadays as it relies on self-evaluation and rating questionnaires, which are highly influenced by subjective bias. Introducing more objective, quantitative, and sensitive methods to characterize mental fatigue could be critical to improve its management and the understanding of its connection to other clinical conditions.

Objective

This paper aimed to study the feasibility of using keystroke biometrics for mental fatigue detection during natural typing. As typing involves multiple motor and cognitive processes that are affected by mental fatigue, our hypothesis was that the information captured in keystroke dynamics can offer an interesting mean to characterize users’ mental fatigue in a real-world setting.

Methods

We apply domain transformation techniques to adapt and transform TypeNet, a state-of-the-art deep neural network, originally intended for user authentication, to generate a network optimized for the fatigue detection task. All experiments were conducted using 3 keystroke databases that comprise different contexts and data collection protocols.

Results

Our preliminary results showed area under the curve performances ranging between 72.2% and 80% for fatigue versus rested sample classification, which is aligned with previously published models on daily alertness and circadian cycles. This demonstrates the potential of our proposed system to characterize mental fatigue fluctuations via natural typing patterns. Finally, we studied the performance of an active detection approach that leverages the continuous nature of keystroke biometric patterns for the assessment of users’ fatigue in real time.

Conclusions

Our results suggest that the psychomotor patterns that characterize mental fatigue manifest during natural typing, which can be quantified via automated analysis of users’ daily interaction with their device. These findings represent a step towards the development of a more objective, accessible, and transparent solution to monitor mental fatigue in a real-world environment.

Clear Speech Variants: An Investigation of Intelligibility and Speaker Effort in Speakers With Parkinson's Disease

PURPOSE

This study investigated the effects of three clear speech variants on sentence intelligibility and speaking effort for speakers with Parkinson's disease (PD) and age- and sex-matched neurologically healthy controls.

METHOD

Fourteen speakers with PD and 14 neurologically healthy speakers participated. Each speaker was recorded reading 18 sentences from the Speech Intelligibility Test in their habitual speaking style and for three clear speech variants: clear (SC; given instructions to speak clearly), hearing impaired (HI; given instructions to speak with someone with a hearing impairment), and overenunciate (OE; given instructions to overenunciate each word). Speakers rated the amount of physical and mental effort exerted during each speaking condition using visual analog scales (averaged to yield a metric of overall speaking effort). Sentence productions were orthographically transcribed by 50 naive listeners. Linear mixed-effects models were used to compare intelligibility and speaking effort across the clear speech variants.

RESULTS

Intelligibility was reduced for the PD group in comparison to the control group only in the habitual condition. All clear speech variants significantly improved intelligibility above habitual levels for the PD group, with OE maximizing intelligibility, followed by the SC and HI conditions. Both groups rated speaking effort to be significantly higher for both the OE and HI conditions versus the SC and habitual conditions.

DISCUSSION

For speakers with PD, all clear speech variants increased intelligibility to a level comparable to that of healthy controls. All clear speech variants were also associated with higher levels of speaking effort than habitual speech for the speakers with PD. Clinically, findings suggest that clear speech training programs consider using the instruction "overenunciate" for maximizing intelligibility. Future research is needed to identify if high levels of speaking effort elicited by the clear speech variants affect long-term sustainability of the intelligibility benefit.

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.

Depressive symptoms before and after Parkinson’s diagnosis—A longitudinal analysis

Background

Depression is common in Parkinson’s disease (PD). It is however unclear when and how depressive symptoms develop and progress in the course of PD development.

Objective

To assess how depressive symptoms evolve in PD, using repeated measures.

Methods

In 2994 older adults, ages 70–79 years, depressive symptoms were assessed 8 times over 11 years using the 10-item Center for Epidemiologic Studies Depression Scale (CESD-10). For each PD patient at each time point, we calculated the difference between CESD-10 score and its expected value estimated based on data from individuals without PD, and then realigned the time scale in reference to the year of PD diagnosis. We examined longitudinal changes in CESD-10 scores before and after PD diagnosis using a joint modeling approach to account for competing risks of non-participation and death.

Results

A total of 79 PD patients were identified at enrollment or during the follow-up, with repeatedly assessed depressive symptom data up to 9 years before and after PD diagnosis. We found a monotonic trend of increasing CESD-10 score in PD patients throughout the observational period (p = 0.002). The observed scores became higher than expected approximately 7 years before PD diagnosis and significantly different 1 year before PD diagnosis.

Conclusions

Increasing depressive symptomatology appears to precede PD diagnosis by a few years.

Exploring the management approaches of cytokines including viral infection and neuroinflammation for neurological disorders

Considerable evidence supports that cytokines are important mediators of pathophysiologic processes within the central nervous system (CNS). Numerous studies have documented the increased production of various cytokines in the human CNS in various neurological and neuropsychiatric disorders. Deciphering cytokine actions in the intact CNS has important implications for our understanding of the pathogenesis and treatment of these disorders. The purpose of this study is to discuss the recent research on treating cytokine storm and amyloids, including stroke, Parkinson's disease (PD), Alzheimer's disease (AD), Huntington's condition, Multi-sclerosis (MS), Amyotrophic Lateral Sclerosis (ALS). Neuroinflammation observed in neurological disorders has a pivotal role in exacerbating Aβ burden and tau hyperphosphorylation, suggesting that stimulating cytokines in response to an undesirable external response could be a checkpoint for treating neurological disorders. Furthermore, the pro-inflammatory cytokines help our immune system through a neuroprotective mechanism in clearing viral infection by recruiting mononuclear cells. This study reveals that cytokine applications may play a vital role in providing novel regulation and methods for the therapeutic approach to neurological disorders and the causes of the deregulation, which is responsible for neuroinflammation and viral infection. However, it needs to be further investigated to clarify better the mechanisms of cytokine release in response to various stimuli, which could be the central point for treating neurological disorders.

Validation of the Traditional Chinese Version of the Pittsburgh Fatigability Scale for Older Adults

OBJECTIVES

The Pittsburgh Fatigability Scale (PFS) is a self-administered 10-item tool to measure physical and mental fatigability in older adults. The aim of the current study was to validate the psychometric properties of the traditional Chinese version of PFS (TC-PFS).

METHODS

We recruited 114 community-dwellingolder adults, where 35 were diagnosed with late-life depression (LLD), 26 with mild cognitive impairment (MCI), and 53 were cognitively normal (CN) from a larger community study of older adults. Statistical analyses were done separately for TC-PFS Physical and Mental subscales. Factor analysis was used for reliability, Cronbach's alpha for internal consistency, Pearson's correlation for construct validity, and group comparison for discriminative validity.

RESULTS

Factor analysis revealed a two-factor structure for both the TC-PFS Physical and Mental subscales with high reliability (α = 0.89 and 0.89, respectively). Patients with LLD had the highest PFS scores, with 80.0% and 82.9% classified as having greater physical and mental fatigability. For concurrent validity, we found moderate associations with the vitality and physical functioning subscales of the 36-Item Short Form Health Survey. For convergent validity, TC-PFS showed moderate association with emotional-related psychometrics, particularly for the Physical subscale in those with LLD. In contrast, TC-PFS Mental subscale showed correlations with cognitive function, particularly in the MCI group.

CONCLUSIONS

Our results indicate that the TC-PFS is a valid instrument to measure perceived physical and mental fatigability in older Taiwanese adults.Clinical implications: Perceived fatigability reflects the underlying physical, mental or cognitive function in older adults with or without depression.

A qualitative examination of apathy and physical activity in Huntington's and Parkinson's disease

Aim: In Huntington's disease (HD) and Parkinson's disease (PD), apathy is a frequently cited barrier to participation in physical activity. Current diagnostic criteria emphasize dissociable variants of apathy that differentially affect goal-directed behavior. How these dimensions present and affect physical activity in HD and PD is unknown. Methods: Using a qualitative approach, we examined the experience of apathy and its impact on physical activity in 20 people with early-manifest HD or idiopathic PD. Results: Two major themes emerged: the multidimensionality of apathy, including initiation or goal-identification difficulties, and the interplay of apathy and fatigue; and facilitators of physical activity, including routines, safe environments and education. Conclusion: Physical activity interventions tailored to apathy phenotypes may maximize participant engagement.

Dietary Patterns and Nonmotor Symptoms in Parkinson's Disease: A Cross-Sectional Analysis

OBJECTIVE

Evidence-based treatment for nonmotor symptoms in Parkinson's disease (PD) is limited. Lifestyle-based improvements including dietary changes may be a potential management strategy. The intent of this research was to investigate the extent to which 3 dietary indices (Mediterranean-DASH Diet Intervention for Neurodegenerative Delay [MIND], Dietary Inflammation Index [DII], and Healthy Diet Indicator [HDI-2020]) are associated with overall and individual nonmotor symptom severity among individuals with PD.

METHOD

An exploratory cross-sectional analysis of dietary (food frequency questionnaire) and clinical data was undertaken, including measures of overall nonmotor symptom severity, such as fatigue, depression, anxiety, apathy, sleep problems, daytime sleepiness, and cognitive impairment. The relationship between each dietary score and symptom outcome was assessed by linear regression for continuous variables and through general linear model analysis for tertiles of dietary adherence.

RESULTS

None of the dietary indices significantly predicted the total nonmotor symptom severity score. The HDI predicted a significant decrease in fatigue scores as measured by the NeuroQoL fatigue item (standardized β = -.19, p = 0.022), after adjusting for age, sex, energy intake, years since diagnosis, physical activity level, education, and smoking. Self-reported depression symptoms reduced by .17 (standardized β) for each unit increase in HDI score (p = 0.035), after controlling for age, gender, energy intake, and years since diagnosis. No other significant associations were evident between dietary scores and any other nonmotor symptoms.

CONCLUSIONS

Our results indicate that fatigue and depression in PD may be modified by diet; however, more research is needed using a larger sample to replicate these findings.

Supplemental data for this article is available online at https://doi.org/10.1080/07315724.2022.2056544 .

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.

Deconstructing Apathy in Parkinson's Disease: Challenges in Isolating Core Components of Apathy From Depression, Anxiety, and Fatigue

Apathy, fatigue and depression are amongst the most debilitating non-motor syndromes of Parkinson's disease (PD). The aim of this study was to examine the prevalence of apathy, depression, anxiety and fatigue and whether these syndromes are separable in PD. A total of 337 patients were examined using the Unified Parkinson's Disease Rating Scale (UPDRS part III), the Apathy Evaluation Scale, the Hospital Anxiety and Depression Scale and the Fatigue Severity Scale. Using standard cutoff criteria, the prevalence rates of significant apathy, mild-to-severe depression, mild-to-severe anxiety and severe fatigue were 23.7, 13.4, 15.4, and 17.8%, respectively. Next, confirmatory factor analysis was employed of items from these three clinical scales. A priori hypothesis testing including four different factors (reduced motivation/interest, physical fatigue, reduced pleasure, anxiety) was performed. The factor analysis revealed strong fit statistics for the model with χ2 (57, N = 377) = 58.9, p = 0.41, CMIN/DF = 1,034, NFI = 0.977, CFI = 0.999, IFI = 0.999, RFI = 0.968, and TLI = 0.999. The RMSEA was 0.01, and the standardized RMR was 0.027. These results support the hypothesis that apathy, fatigue, depression and anxiety represent prevalent syndromes that can be separated in Parkinson's disease and that apathy is not just a subcomponent of depression or fatigue. The results of this study may contribute to a clearer diagnostic process for apathy, fatigue and depression and may aid in patient care.

Impaired dopamine metabolism is linked to fatigability in mice and fatigue in Parkinson's disease patients

Fatigue is a common symptom of Parkinson’s disease that compromises significantly the patients’ quality of life. Despite that, fatigue has been under-recognized as symptom, its pathophysiology remains poorly understood, and there is no adequate treatment so far. Parkinson’s disease is characterized by the progressive loss of midbrain dopaminergic neurons, eliciting the classical motor symptoms including slowing of movements, muscular rigidity and resting tremor. The dopamine synthesis is mediated by the rate-limiting enzyme tyrosine hydroxylase, which requires tetrahydrobiopterin as a mandatory cofactor. Here, we showed that reserpine administration (1 mg/kg, two intraperitoneal injections with an interval of 48 h) in adult Swiss male mice (8–10 weeks; 35–45 g) provoked striatal depletion of dopamine and tetrahydrobiopterin, and intolerance to exercise. The poor exercise performance of reserpinized mice was not influenced by emotional or anhedonic factors, mechanical nociceptive thresholds, electrocardiogram pattern alterations or muscle-impaired bioenergetics. The administration of levodopa (100 mg/kg; i.p.) plus benserazide (50 mg/kg; i.p.) rescued reserpine-induced fatigability-like symptoms and restored striatal dopamine and tetrahydrobiopterin levels. Remarkably, it was observed, for the first time, that impaired blood dopamine metabolism inversely and idependently correlated with fatigue scores in eighteen idiopathic Parkinson’s disease patients (male n = 13; female n = 5; age 61.3 ± 9.59 years). Altogether, this study provides new experimental and clinical evidence that fatigue symptoms might be caused by the impaired striatal dopaminergic neurotransmission, pointing to a central origin of fatigue in Parkinson’s disease.

Numerical activities of daily living: a short version

Specific impairments in numerical functions may cause severe problems in everyday life that cannot be inferred from the available scales evaluating instrumental activities of daily living. The Numerical Activities of Daily living (NADL) is a battery designed to assess the patient's performance in everyday activities involving numbers (Informal Test) and in more scholastic capacities (Formal Test). A downside of this battery is its duration (45 min). The aim of the present study is to build a shorter version of NADL to make it more suitable for clinical and research purposes. The shortening procedure involved only the Formal test, and followed two steps: (i) a correlation of subtests with the general scores, and (ii) an item-analysis within the subtests previously showing higher correlations. Correlations between NADL-Short and NADL original version, and the new cut-offs were calculated. Lastly, the relationship between NADL-Short and other brief cognitive screening tests used in the clinical practice was evaluated in neurological patients and healthy controls. The NADL-Short includes the original Informal Test and the shortened Formal Test. It is a quick and easy clinical tool (15 min) to assess numerical abilities applied to informal and formal situations. It correlates highly with the original battery (Kendall's tau greater than 0.6 across tasks) and the cut-offs correctly identify impaired performance (accuracy of 95% or above). Correlation analysis showed a low positive correlation between NADL-Short and other brief cognitive scales. These findings suggest that it is appropriate to use specific tools to make inferences about a person's numerical abilities.

Numerical Activities of Daily Living - Financial: a short version

Financial capacity is the ability to manage money and finances according to a person's values and self-interests. In Italy, the first instrument specifically designed to assess financial capacity has recently been developed: the Numerical Activities of Daily Living - Financial (NADL-F). The aims of this study are (1) to prepare a shorter version of NADL-F and (2) to examine the relationship between the new short version and a measure of general cognitive functioning of comparable length, the MMSE. After an item analysis performed on NADL-F, the items presenting a higher internal consistency were selected. The resulting NADL-F Short is a reliable, easy to use, and quick to administer tool for assessing financial capacity both in clinical and legal practice. Correlation analysis showed a low positive correlation between four NADL-F Short tasks and the MMSE, for the healthy participants group. For the patient group, instead, a low-moderate correlation was found for all the NADL-F Short tasks, except one. Many participants scoring high in the MMSE (both healthy controls and neurological patients) showed low NADL-F Short scores. These findings suggest that it is not correct to use generic tools like the MMSE to make inferences on a person's financial capacity.

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.

Fatigability and Cardiorespiratory Impairments in Parkinson's Disease: Potential Non-Motor Barriers to Activity Performance

Parkinson's disease (PD) is the second most common neurodegenerative condition after Alzheimer's disease, affecting an estimated 160 per 100,000 people 65 years of age or older. Fatigue is a debilitating non-motor symptom frequently reported in PD, often manifesting prior to disease diagnosis, persisting over time, and negatively affecting quality of life. Fatigability, on the other hand, is distinct from fatigue and describes the magnitude or rate of change over time in the performance of activity (i.e., performance fatigability) and sensations regulating the integrity of the performer (i.e., perceived fatigability). While fatigability has been relatively understudied in PD as compared to fatigue, it has been hypothesized that the presence of elevated levels of fatigability in PD results from the interactions of homeostatic, psychological, and central factors. Evidence from exercise studies supports the premise that greater disturbances in metabolic homeostasis may underly elevated levels of fatigability in people with PD when engaging in physical activity. Cardiorespiratory impairments constraining oxygen delivery and utilization may contribute to the metabolic alterations and excessive fatigability experienced in individuals with PD. Cardiorespiratory fitness is often reduced in people with PD, likely due to the combined effects of biological aging and impairments specific to the disease. Decreases in oxygen delivery (e.g., reduced cardiac output and impaired blood pressure responses) and oxygen utilization (e.g., reduced skeletal muscle oxidative capacity) compromise skeletal muscle respiration, forcing increased reliance on anaerobic metabolism. Thus, the assessment of fatigability in people with PD may provide valuable information regarding the functional status of people with PD not obtained with measures of fatigue. Moreover, interventions that target cardiorespiratory fitness may improve fatigability, movement performance, and health outcomes in this patient population.

Management of psychiatric disorders in Parkinson's disease : Neurotherapeutics - Movement Disorders Therapeutics

Affective disorders (depression and anxiety), psychosis, impulse control disorders, and apathy are common and sometimes disabling psychiatric conditions in Parkinson disease (PD). Psychiatric aspects of PD are associated with numerous adverse outcomes, yet in spite of this and their high frequency, there remains incomplete understanding of epidemiology, presentation, risk factors, neural substrate, and management strategies. Psychiatric features are typically co- or multimorbid, and there is great intra- and interindividual variability in presentation [1]. The neuropathophysiological changes that occur in PD, as well as the association between PD treatment and particular psychiatric disorders, suggest a neurobiological contribution to many psychiatric symptoms. There is evidence that psychiatric disorders in PD are still under-recognized and undertreated, and although psychotropic medication use is common, randomized controlled trials demonstrating efficacy and tolerability are largely lacking. Future research on neuropsychiatric complications in PD should be oriented toward determining modifiable correlates or risk factors, and most importantly, establishing efficacious and well-tolerated treatment strategies.

Clinical Perspectives of Parkinson's Disease for Ophthalmologists, Otorhinolaryngologists, Cardiologists, Dentists, Gastroenterologists, Urologists, Physiatrists, and Psychiatrists

Parkinson's disease (PD) is a multisystemic disorder characterized by various non-motor symptoms (NMS) in addition to motor dysfunction. NMS include sleep, ocular, olfactory, throat, cardiovascular, gastrointestinal, genitourinary, or musculoskeletal disorders. A range of NMS, particularly hyposmia, sleep disturbances, constipation, and depression, can even appear prior to the motor symptoms of PD. Because NMS can affect multiple organs and result in major disabilities, the recognition and multidisciplinary and collaborative management of NMS by physicians is essential for patients with PD. Therefore, the aim of this review article is to provide an overview of the organs that are affected by NMS in PD together with a brief review of pathophysiology and treatment options.

Body Mass Index, Physical Activity Habits and Physical Function Contribute to Fatigue in the Rest Home Residents

BACKGROUNDS

Fatigue is a common complaint in older adults living in rest homes. The aim of this study was to investigate the factors associated with fatigue among older adults living in a rest home.

METHODS

This cross-sectional study was carried out with a total of 92 older adults. Fatigue was evaluated by the Fatigue Severity Scale (FSS). The sociodemographic characteristics, quadriceps and handgrip strength, functional capacity and physical function were assessed using a structured questionnaire, digital dynamometers, 6-minute walking test and Short Physical Performance Battery, respectively.

RESULTS

The prevalence of fatigue was 67.4%. FSS showed significant correlations with age, female gender, body mass index, physical activity habits, quadriceps strength, handgrip strength, functional exercise capacity, and physical function. However, in the regression analysis, only body mass index, physical activity habits and physical function were responsible for 51% of the variance in fatigue among rest home residents. Physical activity habits and physical function were the best predictors of fatigue explaining 47.5% of variance.

CONCLUSION

This study demonstrated that body mass index, physical activity habits and physical function contributed to fatigue in rest home residents. These factors can be used to identify individuals at high risk of fatigue and to attenuate fatigue levels.

Can fatigue predict walking capacity of patients with Parkinson's disease?

Although fatigue is an expressive symptom of Parkinson's disease (PD), few studies have investigated the association between fatigue, mobility and walking capacity of these patients.

OBJECTIVE

To investigate whether fatigue is an independent factor associated with mobility and the walking capacity in patients with PD.

METHODS

Forty-eight patients with PD (22 with fatigue) were tested for mobility and their walking capacity: Timed Up and Go (TUG), 10-Meter Walk Test (10MWT) at usual and fastest speed, and 6-Minute Walk Test (6MWT). Fatigue was measured with Parkinson's Fatigue Scale (PFS-16). Linear regression analysis was used to investigate if fatigue is an independent factor contributing to variance in mobility and walking capacity.

RESULTS

There was a positive correlation between PFS-16 and TUG (rs=0.385; p=0.007). There was a negative correlation between PFS-16 and 10MWT at comfortable (r=-0.385; p=0.007) and fast speeds (r=-0.396; p=0.005), and 6MWT (r=-0.472; p=0.001). Linear regression analysis revealed that fatigue did not explain the variance of TUG and 10MWT. PFS-16, age and section III of UPDRS explained 49.6% (adjusted R2; p<0.001) variance in the 6MWT, and fatigue was the most significant predictor (F=-32.1; p=0.022).

CONCLUSIONS

Fatigue is an independent factor contributing to the distance covered during 6MWT in patients with PD. Our results highlight the importance of recognition and management of this symptom.

The effect of fatigue on balance performance in Parkinson's disease

Introduction

Balance loss and falls are a common and multifactorial finding in persons with Parkinson's Disease (pwPD). Objective fatigability is thought to contribute to falls in other neurologic conditions, but its impact on balance in pwPD is not known. The two-fold purpose of this study was to: 1) establish that a 6-minute walk (6MW_Fast) is a stimulus to subjective fatigue for pwPD; and, 2) determine if the Mini Balance Evaluation Systems Test (MBT) is sensitive to change that was induced by a fatiguing condition.

Methods

Using a randomized crossover design, 19 research participants performed a Mini Balance Evaluation Systems Test (MBT) before and after either a ‘fast’ 6-minute walk (6MW_Fast) to induce fatigue or a 6-minute rest.

Results

VASF scores increased after the 6MW_Fast. Total MBT scores in research participants with Modified Hoehn and Yahr (H&Y) scores of 3.0 and above differed significantly before and after the ‘fast’ 6-minute walk (p = .007, n = 9) while participants with H&Y scores of 1.5 to 2.5 (p = .084, n = 10) did not, suggesting that more disabled pwPD were more likely to experience fatigability that interfered with balance.

Conclusions

A 6MW_Fast is a sufficient stimulus to induce subjective fatigue in pwPD and to decrease total MBT scores for more disabled pwPD. Balance evaluations should occur when pwPD are in fatigued and unfatigued states to determine whether fatigue has an impact on balance performance.

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Both subjective fatigue and objective fatigability can occur in Parkinsons Disease (PD).

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Objective fatigability may be a factor in balance impairment in persons with PD.

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Balance assessments in PD should be made with the patient in both a fatigued and non fatigued state.

Brazilian version of the Multidimensional Fatigue Inventory for Parkinson’s disease

Abstract Introduction: The multidimensional fatigue inventory (MFI) has not been applied in Brazilian Parkinson`s disease (PD) population due to the lack of validation. Objective: The aim of this study was to cross-culturally adapt, to validate, and investigate the psychometric properties of Brazilian version of the MFI in PD. Method: Idiopathic PD individuals (N = 90) were recruited. The MFI was translated into Brazilian Portuguese using established forward-backward translation procedures, and the psychometric properties were evaluated. All individuals were assessed by socio-clinical questionnaire, Mini-Mental State Examination (MMSE), Unified Parkinson’s Disease Rating Scale (MDS-UPDRS Part I-IV), Hoehn-Yahr disability scale (HY), hospital anxiety and depression scale (HADS), fatigue severity scale (FSS), Parkinson Fatigue Scale (PFS-16) and MFI-PD/ BR with retest of the MFI-PD/BR after seven days. Results: The adaptation phase kept the same items of original MFI-PD. No data missing, floor nor ceiling effects were found. The overall Cronbach's alpha coefficient for the 20 items was 0.81, ranging from 0.73 to 0.81 for each of the five subscales. Bland and Altman analysis showed no systematic differences between assessments. The intraclass correlation coefficient test-retest was higher or equal 0.70 (p < 0.01) for the MFI-PD/BR score, which was moderately correlated with the HADS, MDS-UPDRS score (motor examination, motor and non-motor experiences of daily living and motor complications), FSS and PFS-16. It was revealed the MFI-PD/ BR > 55 points as cut-off point to indicate fatigued subjects with accuracy of 0.84 (p < 0.001). Conclusion: The MFI-PD/BR can be considered a valid and reproducible instrument for assessing PD-related fatigue.

Cognitive Fatigability Interventions in Neurological Conditions: A Systematic Review

INTRODUCTION

Although fatigue is a well-studied concept in neurological disease, cognitive fatigability (CF) is less understood. While most studies measure fatigue using subjective self-report, fewer have measured CF objectively. Given the negative impact of CF on quality-of-life, there is a need for targeted interventions. The objective of this review was to determine which procedural, behavioural and pharmacological treatments for objectively measured CF are available to people living with neurological conditions.

METHODS

In accordance with the PRISMA guidelines, systematic searches for randomized control trials (RCTs), case-controlled studies and case reports/series were conducted across the Ovid Medline, PsycInfo, EMBASE and Cochrane Library databases. English-language articles published between 1980 and February 2019 were considered for eligibility. Included were those that objectively measured CF in individuals with neurological disease/disorder/dysfunction between the ages of 18 and 65 years. Studies were reviewed using a modified Cochrane Data Extraction Template. Risk of bias was assessed using the Cochrane Risk of Bias tool. The review process was facilitated using Covidence software (www.covidence.org). Two authors reviewed articles independently, with a third resolving conflicts regarding article inclusion.

RESULTS

The search identified 450 records. After duplicates were removed and remaining titles/abstracts were screened for eligibility, 28 full-text articles were assessed, and two studies were included in the qualitative synthesis. Studies were a priori divided into those with pharmacological, procedural or behavioural interventions. Two studies met eligibility criteria; both of these included participants with multiple sclerosis. One study utilized a procedural intervention (i.e. transcranial direct current stimulation), while the other utilized a pharmacological intervention (i.e. fampridine-SR). Studies were evaluated for risk of bias, and evidence from both eligible studies was discussed.

CONCLUSION

Despite the positive results of the procedural intervention, the paucity of eligible studies and the nascent nature of the field suggests that more studies are required before firm conclusions can be drawn regarding the amenability of CF to treatment.

TRIAL REGISTRATION

The review was registered with PROSPERO (CRD42019118706).

The Neuropsychiatry of Parkinson Disease: A Perfect Storm

Affective disorders, cognitive decline, and psychosis have long been recognized as common in Parkinson disease (PD), and other psychiatric disorders include impulse control disorders, anxiety symptoms, disorders of sleep and wakefulness, and apathy. Psychiatric aspects of PD are associated with numerous adverse outcomes, yet in spite of this and their frequent occurrence, there is incomplete understanding of epidemiology, presentation, risk factors, neural substrate, and management strategies. Psychiatric features are typically multimorbid, and there is great intra- and interindividual variability in presentation. The hallmark neuropathophysiological changes that occur in PD, plus the association between exposure to dopaminergic medications and certain psychiatric disorders, suggest a neurobiological basis for many psychiatric symptoms, although psychological factors are involved as well. There is evidence that psychiatric disorders in PD are still under-recognized and undertreated and although psychotropic medication use is common, controlled studies demonstrating efficacy and tolerability are largely lacking. Future research on neuropsychiatric complications in PD should be oriented toward determining modifiable correlates or risk factors and establishing efficacious and well-tolerated treatment strategies.

Defective Tool Embodiment in Body Representation of Individuals Affected by Parkinson's Disease: A Preliminary Study

When efficiently used for action, tools become part of the body, with effect on the spatial-temporal movement parameters and body size perception. Until now, no previous investigation has been reported about tool embodiment in Parkinson’s disease (PD), which is a neurological disease characterized by several sensory and motor symptoms affecting body and action. We enrolled 14 individuals affected by PD and 18 healthy individuals as controls. We studied the spatial-temporal parameters on self-paced free pointing movement task, via an optoelectronic system, before and after a short training in which a 27-cm long rod was used to point toward a far target. Moreover, we investigated changes in estimation of arm length through the Tactile Estimation Task. After the tool-use training, controls showed changes in spatial-temporal parameters: they were slower to perform movements and reported a higher value of deceleration than the baseline. However, such a difference did not emerge in the PD individuals. In the Tactile Discrimination Task, no difference emerged before and after the tool-use training in both groups. Our results were suggestive of possible difficulties of the tool embodiment process in PD. We discussed our results in relation to aberrant multisensory integration as well as in terms of the effect of PD sensory and motor symptoms on body schema plasticity. The present study points at a novel way to conceive PD sensory motor signs and symptoms in terms of their effect on individuals’ body representation.

The relationship between temperament and depression in Parkinson's disease patients under dopaminergic treatment

AIM

The risk factors for depressive symptoms in patients with Parkinson's disease (PD) under dopaminergic drug treatment are unclear. In this study, we examined whether some temperament traits are related to the presence of comorbid depression in PD patients, independent of the characteristics of illness and drug treatment.

METHODS

The participants in this study were 74 patients with idiopathic PD who were already treated with stable doses of levodopa or dopamine agonists. Depressive (n = 20) and non-depressive (n = 52) PD patients were assessed by means of the Unified Parkinson's Disease Rating Scale, Beck Depression Inventory, and Temperament Evaluation of Memphis, Pisa, Paris and San Diego Auto-questionnaire. The doses of levodopa and dopamine agonists were converted into levodopa equivalent daily dose.

RESULTS

The duration of treatment in the depressive group was significantly longer than in the non-depressive group (P = 0.03). The depressive patients had significantly higher scores on the Unified Parkinson's Disease Rating Scale than the non-depressive patients. Depressive (P < 0.0001), cyclothymic (P < 0.0001), anxious (P < 0.0001), and irritable (P = 0.02) temperament scores were significantly higher in depressive than in non-depressive patients. Hyperthymia scores were significantly higher in non-depressive patients than in depressive patients (P = 0.01). Logistic regression analysis revealed that depressive temperament traits (P = 0.03) significantly predicted the diagnosis of depression. In contrast, hyperthymic temperament seemed to be associated with the absence of depression (P = 0.006).

CONCLUSION

Our results indicated that the severity of PD and duration of dopaminergic treatment were not predictive of the development of depression in PD patients. Depressive temperament strongly predicted the development of depression in our sample. Hyperthymic temperament seemed to be associated with patients without depression. We suggest that depressive temperament traits seem to be related to depression, while hyperthymic temperament may have a protective role in the risk of depression in PD patients.

Parkinson's disease: Diagnosis and appreciation of comorbidities

Parkinson's disease (PD) is a complex neuropsychiatric disorder that manifests with a variety of motor and nonmotor symptoms. Its incidence increases with age. It is important for clinicians to be able to distinguish symptoms of aging and other comorbidities from those of PD. The diagnosis of PD has traditionally been rendered using strict criteria that mainly rely on the cardinal motor symptoms of rest tremor, rigidity, and bradykinesia. However, newer diagnostic criteria proposed by the Movement Disorders Society for diagnosis of PD collectively reflect a greater appreciation for the nonmotor symptoms. The treatment of PD remains symptomatic and the most noticeable improvements have been documented in the motor symptoms. Levodopa remains the gold standard for therapy, however there are now many other potential medical and surgical treatment strategies. Nonmotor symptoms have been shown to affect quality of life more than the motor symptoms. There is ongoing research into symptomatic and disease modifying treatments. Given the multisystem involvement in PD, an interdisciplinary patient-centered approach is recommended by most experts. This chapter addresses first the diagnostic approach and the many geriatric considerations. This is followed by a review of the nonmotor symptoms. Finally, a summary of current treatment strategies in PD is presented along with potential treatment complications.

Comparative sensitivity of the MoCA and Mattis Dementia Rating Scale-2 in Parkinson's disease

BACKGROUND

Clinicians and researchers commonly use global cognitive assessments to screen for impairment. Currently there are no published studies directly comparing the sensitivity and specificity of the Montreal Cognitive Assessment and Mattis Dementia Rating Scale-2 in PD. The objective of this study was to identify the relative sensitivity and specificity of the Montreal Cognitive Assessment and Mattis Dementia Rating Scale-2 in PD.

METHODS

The Montreal Cognitive Assessment and Mattis Dementia Rating Scale-2 were administered to training and validation cohorts. Cutoff scores were determined within the training cohort (n = 85) to optimize sensitivity and specificity for cognitive impairment and were applied to an independent validation cohort (n = 521).

RESULTS

The Montreal Cognitive Assessment was consistently sensitive across training and validation cohorts (90.0% and 80.3%, respectively), whereas the Mattis Dementia Rating Scale-2 was not (87.5% and 60.3%, respectively). In individual domains, the Montreal Cognitive Assessment remained sensitive to memory and visuospatial impairments (91.9% and 87.8%, respectively), whereas the Mattis Dementia Rating Scale-2 was sensitive to executive impairments (86.2%).

CONCLUSION

The Montreal Cognitive Assessment and Mattis Dementia Rating Scale-2 demonstrated individual strengths. Future work should focus on developing domain-specific cognitive screening tools for PD. © 2018 International Parkinson and Movement Disorder Society.

Does fatigue in Parkinson's disease correlate with autonomic nervous system dysfunction?

BACKGROUND

Despite its negative impact on quality of life, fatigue in Parkinson's disease (PD) remains an under-recognized issue and the underlying pathology is undetermined.

OBJECTIVE

To contribute at understanding the pathogenesis of fatigue in a naturalistic cohort of cognitively intact PD patients.

METHODS

In a Caucasian population of PD patients (n = 27), we evaluated to what extent fatigue (quantified as PFS-16 score) is associated with PD duration and with autonomic dysfunction, studied by both MIBG scintigraphy and autonomic nervous system testing. The latter included the head-up tilt test, Valsalva maneuver, deep breathing, and handgrip tests.

RESULTS

PFS-16 score correlated with disease duration (R = 0.57, p = 0.002). Fatigue showed a clear correlation with deep breathing test (R = - 0.53, p = 0.004) but not with the MIBG H/M ratios.

CONCLUSIONS

Our data are consistent with a multifactorial pathogenesis of fatigue and with effects of dopamine depletion in PD-related fatigue; on the other hand, our findings do not support a role for sympathetic denervation in PD-related fatigue.

Cognitive and Neuropsychiatric Features of Early Parkinson's Disease

The clinical definition of Parkinson's disease (PD) is based on cardinal motor features including bradykinesia as well as an additional symptom of tremor, postural instability, or rigidity. Evidence from neuropathological, imaging, and clinical research suggests a premotor, early phase of PD pathology. Further understanding of the earliest biomarkers of PD is crucial for the development of neuroprotective, disease modifying, cognitive, and psychiatric interventions. Recent research has explored early non-motor markers of PD pathology. This issue is especially timely as the International Parkinson and Movement Disorder Society has recently provided a research definition for prodromal PD which includes combinations of prodromal markers and risk factors aimed at identifying target populations for disease-prevention trials. In this review of early PD, we will outline early non-motor symptoms, early cognitive and neuropsychiatric features, neuropsychological assessment strategies, emerging evidence for early biomarkers, and treatment recommendations.

Self-reported fatigue following intensive care of chronically critically ill patients: a prospective cohort study

Background

Protracted treatment on intensive care unit (ICU) sets the patients at increased risk for the development of chronic critical illness (CCI). Muscular and cardio-respiratory deconditioning are common long-term sequelae, going along with a state of chronic fatigue. At present, findings regarding the frequency, long-term course, and associated factors of self-reported fatigue following ICU treatment of CCI patients are lacking.

Methods

CCI patients with the diagnosis of critical illness polyneuropathy/myopathy (CIP/CIM) were assessed at three time points. Four weeks following the discharge from ICU at acute care hospital (t1), eligibility for study participation was asserted. Self-reported fatigue was measured using the Multidimensional Fatigue Inventory (MFI-20) via telephone contact at 3 (t2, n = 113) and 6 months (t3, n = 91) following discharge from ICU at acute care hospital.

Results

At both 3 and 6 months, nearly every second CCI patient showed clinically relevant fatigue symptoms (t2/t3: n = 53/n = 51, point prevalence rates: 46.9%/45.1%). While total fatigue scores remained stable in the whole sample, female patients showed a decrease from 3 to 6 months. The presence of a coronary heart disease, the perceived fear of dying at acute care ICU, a diagnosis of major depression, and the perceived social support were confirmed as significant correlates of fatigue at 3 months. At 6 months, male gender, the number of medical comorbidities, a diagnosis of major depression, and a prior history of anxiety disorder could be identified. A negative impact of fatigue on the perceived health-related quality of life could be ascertained.

Conclusions

Nearly every second CCI patient showed fatigue symptoms up to 6 months post-ICU. Patients at risk should be informed about fatigue, and appropriate treatment options should be offered to them.

Trial registration

The present study was registered retrospectively at the German Clinical Trials Register (date of registration: 13th of December 2011; registration number: DRKS00003386). Date of enrolment of the first participant to the present trial: 09th of November 2011.

Factors Contributing to Perceived Walking Difficulties in People with Parkinson's Disease

BACKGROUND

While walking difficulties are common in people with Parkinson's disease (PD), little is known about factors that independently contribute to their perceived walking difficulties.

OBJECTIVE

To identify factors that independently contribute to perceived walking difficulties in people with PD.

METHODS

This study involved 243 (62% men) participants; their mean (min-max) age and PD duration were 70 (45-93) and 8 (1-43) years, respectively. A postal survey preceded a home visit that included observations, clinical tests, questions and questionnaires that were administered as a structured interview. Perceived walking difficulties (dependent variable) were assessed with the self-administered generic Walk-12 (Walk-12G, scored 0-42, higher = worse). Independent variables included personal (e.g., age and general self-efficacy) and social environmental factors (e.g., social support and living situation) as well as disease-related factors including motor (e.g., freezing of gait (FOG) and postural instability) and non-motor symptoms (e.g., fatigue and orthostatic hypotension). Linear multiple regression analysis was used to identify factors that independently contributed to perceived walking difficulties.

RESULTS

Eight significant independent variables explained 56.3% of the variance in perceived walking difficulties. FOG was the strongest significant contributing factor to perceived walking difficulties, followed by general self-efficacy, fatigue, PD duration, lower extremity function, orthostatic hypotension, bradykinesia and postural instability.

CONCLUSION

Motor and non-motor symptoms as well as personal factors (i.e., general self-efficacy) seem to be of importance for perceived walking difficulties in PD. These findings might nurture future interventions that address modifiable factors in order to enhance walking ability in people with PD.

Brain metabolic correlates of fatigue in Parkinson's disease: a PET study

PURPOSE

The neural bases of fatigue in Parkinson's disease (PD) remain uncertain. We aimed to assess the brain metabolic correlates of fatigue in patients with PD.

PATIENTS AND METHODS

Twenty-seven PD patients without clinically relevant depression (17-item Hamilton Depression Rating Scale (HAMD) score ≥ 14), apathy (Apathy Scale (AS) score ≥ 14) and excessive daytime somnolence (Epworth Sleepiness Scale (ESS) score ≥ 10) were evaluated with Fatigue Severity Scale (FSS). Each patient had an F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scan. Motor symptoms were measured with the Unified Parkinson's Disease Rating Scale motor part. Levodopa equivalent daily dose for each patient was also calculated. The PET images were analyzed using statistical parametric mapping software. We introduced the age, educational level, HAMD scores, AS scores and ESS scores as covariates.

RESULTS

High FSS scores were associated with brain hypermetabolism in areas including the right middle temporal gyrus (Brodmann area (BA) 37) and left middle occipital gyrus (BA 19). Increased FSS scores correlated with hypometabolism in regions such as the right precuneus (BA 23), left inferior frontal gyrus (BA 45) and left superior frontal gyrus (orbital part, BA 11).

CONCLUSION

This study demonstrates that brain areas including frontal, temporal and parietal regions indicative of emotion, motivation and cognitive functions are involved in fatigue in PD patients.

Gender Differences of Nonmotor Symptoms Affecting Quality of Life in Parkinson Disease

BACKGROUND/AIMS

Gender differences of health-related quality of life (HRQoL) in patients with various disorders have been reported. Various nonmotor symptoms (NMSs) also affect the patients' lives and HRQoL, even in the early stages of Parkinson disease (PD). Our study aimed to identify whether there are gender differences of HRQoL in PD patients in the early stages, and which NMSs are associated with HRQoL depending on gender.

METHOD

Eighty-nine PD patients (47 males, 42 females) and 36 healthy controls were enrolled. We evaluated HRQoL, NMSs, and their associations in each gender.

RESULT

The total Parkinson Disease Quality of Life Questionnaire and Beck Anxiety Inventory scores were higher in female patients than in male patients. The correlation analysis revealed no association between NMSs and HRQoL in male patients. In female patients, HRQoL was highly correlated with depression, and moderately associated with fatigue.

CONCLUSIONS

Gender differences of an association between HRQoL and NMSs exist in PD. We found that fatigue and depression were the main determinants of poor HRQoL in female patients even in the early stages. We suggest that a gender-specific therapeutic approach is important, and it is necessary to pay special attention to the predictors associated with causing poor HRQoL.

Alterations in regional homogeneity of resting-state brain activity in fatigue of Parkinson's disease

Fatigue is a common complaint in patients with Parkinson's disease (PD). However, the neural bases of fatigue in PD remain uncertain. In this cross-sectional study, our aim was to study the change of the local brain function in PD patients with fatigue. Among 49 patients with PD, 17 of them had fatigue and the remaining 32 patients without fatigue, and 25 age- and gender-matched healthy controls were enrolled. All subjects were evaluated with Fatigue Severity Scale (FSS) and had a resting-state functional magnetic resonance imaging (rs-fMRI) scan. The fMRI images were analyzed using regional homogeneity (ReHo) to study the change of the local brain function. ReHo analysis controlling for gray matter volume, age, gender, and education showed decreased ReHo in the left anterior cingulate cortex (ACC) and the right superior frontal gyrus (dorsolateral part), and increased ReHo in the left postcentral gyrus and the right inferior frontal gyrus (orbital and triangular part), compared PD-F with PD-NF; In PD patients, the regional activity in the left ACC and the right superior frontal gyrus (dorsolateral part) was negatively correlated with the FSS scores, while that in the left postcentral gyrus, the right inferior frontal gyrus (orbital and triangular part) was positively correlated with the FSS scores. This study demonstrates that brain areas including frontal, postcentral and ACC regions indicative of sensory, motor, and cognitive systems are involved in fatigue in PD patients.

Fatigue and Muscle Strength Involving Walking Speed in Parkinson's Disease: Insights for Developing Rehabilitation Strategy for PD

Background. Problems with gait in Parkinson's disease (PD) are a challenge in neurorehabilitation, partly because the mechanisms causing the walking disability are unclear. Weakness and fatigue, which may significantly influence gait, are commonly reported by patients with PD. Hence, the aim of this study was to investigate the association between weakness and fatigue and walking ability in patients with PD. Methods. We recruited 25 patients with idiopathic PD and 25 age-matched healthy adults. The maximum voluntary contraction (MVC), twitch force, and voluntary activation levels were measured before and after a knee fatigue exercise. General fatigue, central fatigue, and peripheral fatigue were quantified by exercise-induced changes in MVC, twitch force, and activation level. In addition, subjective fatigue was measured using the Multidimensional Fatigue Inventory (MFI) and Fatigue Severity Scale (FSS). Results. The patients with PD had lower activation levels, more central fatigue, and more subjective fatigue than the healthy controls. There were no significant differences in twitch force or peripheral fatigue index between the two groups. The reduction in walking speed was related to the loss of peripheral strength and PD itself. Conclusion. Fatigue and weakness of central origin were related to PD, while peripheral strength was important for walking ability. The results suggest that rehabilitation programs for PD should focus on improving both central and peripheral components of force.

Domain-specific accuracy of the Montreal Cognitive Assessment subsections in Parkinson's disease

OBJECTIVE

The Montreal Cognitive Assessment (MoCA) is among the most widely adopted screening tools for cognitive impairment because it includes tests in multiple domains and is available in 55 languages. The MoCA is often the only formal cognitive assessment available when comprehensive neuropsychological testing is not practical, such as rural clinical settings or large retrospective and multi-lingual research settings. However, the MoCA domain-specific subsections have never been formally assessed for sensitivity or specificity. Therefore, in Parkinson's disease, we examined whether the subsections of the MoCA could identify cognitive impairment within specific cognitive domains.

METHODS

We administered a comprehensive neuropsychological battery to 85 Parkinson's disease participants, who were then categorized as with or without cognitive impairment, with respect to global cognition and in five cognitive domains. We then assessed the domain-specific categorization of the MoCA subsections compared to the full neuropsychology battery.

RESULTS

All MoCA subsections predicted impairment in their respective cognitive domain. However, the executive subsection showed the highest sensitivity and specificity (89.3% and 82.5%, respectively), followed by visuospatial (93.3% and 45.7%, respectively) and memory (84.6% and 56.5%, respectively).

CONCLUSION

The MoCA is a useful screening tool for PD global cognitive and executive functions. The MoCA is also highly sensitive to visuospatial and memory impairment, but with limited specificity and accuracy these subsections should be interpreted with caution.

Abnormal Resting-State Neural Activity and Connectivity of Fatigue in Parkinson's Disease

AIMS

Fatigue is a common burdensome problem in patients with Parkinson's disease (PD), but its pathophysiological mechanisms are poorly understood. This study aimed at investigating the neural substrates of fatigue in patients with PD.

METHODS

A total of 17 PD patients with fatigue, 32 PD patients without fatigue, and 25 matched healthy controls were recruited. The 9-item fatigue severity scale (FSS) was used for fatigue screening and severity rating. Resting-state functional magnetic resonance imaging (RS-fMRI) data were obtained from all subjects. Amplitude of low-frequency fluctuations (ALFF) was used to measure regional brain activity, and functional connectivity (FC) was applied to investigate functional connectivity at a network level.

RESULTS

PD-related fatigue was associated with ALFF changes in right middle frontal gyrus within the attention network and in left insula as well as right midcingulate cortex within the salience network. FC analysis revealed that above three regions showing ALFF differences had altered functional connectivity mainly in the temporal, parietal, and motor cortices.

CONCLUSION

Our findings do reveal that abnormal regional brain activity within attention and salience network and altered FC of above abnormal regions are involved in neural mechanism of fatigue in patients with PD.