Patients With Parkinson's Disease Research Articles

Remote levodopa challenge test in Parkinson's disease: Feasibility, reliability, validity and economic value.

The aim was to demonstrate the feasibility, reliability and validity of an in-home remote levodopa challenge test (LCT), as delivered through an online platform, for patients with Parkinson's disease (PwPD). Patients with Parkinson's disease eligible for deep brain stimulation surgery screening were enrolled. Participants sequentially received an in-home remote LCT and an in-hospital standard LCT (separated by 2.71 weeks). A modified Movement Disorder Society Unified Parkinson's Disease Rating Scale Part III omitting rigidity and postural stability items was used in the remote LCT. The reliability of the remote LCT was evaluated using the intraclass correlation coefficient and the concurrent validity was evaluated using the Pearson's correlation coefficient r between the levodopa responsiveness of the remote and standard LCT. Out of 106 PwPD screened, 80 (75.5%) completed both the remote and standard LCT. There was a good reliability (intraclass correlation coefficient 0.81, 95% confidence interval 0.69-0.88) and a strong correlation (r = 0.84, 95% confidence interval 0.77-0.90) between the levodopa responsiveness of the remote and standard LCT. The mean cost for PwPD was estimated to be reduced by 91% by using the remote LCT. The remote LCT is feasible, reliable and valid and may reduce healthcare-related costs for PwPD and their caregivers.

A Delphi Panel of People With Parkinson's Disease Regarding Responsibility: Toward a Preliminary Taxonomy.

A sense of agency is associated with complex occupation-related responsibilities. A taxonomy can guide clinicians in enhancing responsibility in patients with Parkinson's disease (PwPD). To (1) discover levels of responsibility in occupations for PwPD and (2) propose a taxonomy for occupations. A two-round Delphi study with PwPD and a one-round Delphi study with international experts. Electronic survey. PwPD (N = 75) and international experts (N = 8). PwPD expressed their levels of an inherent sense of responsibility for each occupation (1 = very low responsibility, 5 = very high responsibility). International experts rated their level of agreement (5 = strongly agree, 1 = strongly disagree) with each dimension of the taxonomy. A consensus was determined to have been reached if the interquartile range was ≤1 and 70% agreement in two adjacent categories was achieved. Thirty-three occupation categories were deemed as having very high to moderate responsibility for PwPD. Consequences of actions and the presence of others made up the two-dimensional responsibility taxonomy. Occupations have more challenging responsibility characteristics when they are performed with free choice, a level of high physical effort, alone, and with moral consequences. This study yielded the first consensus among PwPD regarding responsibility in occupations as well as a classification system for charting the complexity of responsibility in occupations. The occupation list we have created can be beneficial to health care professionals when providing interventions or conducting outcome assessments. Plain-Language Summary: When planning interventions for patients with Parkinson's disease, it can be helpful for clinicians to be aware of patients' perspectives regarding their sense of responsibility to perform occupations. The use of a systematic sequence of challenging occupations with responsibility attributes ranging from less complex to more complex can help enhance patient occupational participation.

The Effect of Upright Stance and Vision on a Cognitive Task in Elderly Subjects and Patients with Parkinson's Disease.

Standing compared to sitting enhances cognitive performance in healthy subjects. The effect of stance on cognitive performance has been addressed here in patients with Parkinson's disease (PwPD). We hypothesized that a simple cognitive task would be less enhanced in PwPD by standing with respect to sitting, because of a larger cognitive effort for maintenance of standing posture than in healthy subjects. We recruited 40 subjects (20 PwPD and 20 age-matched healthy subjects, HE). Each participant performed an arithmetic task (backward counting aloud by 7) in two postural states, sitting and standing, with eyes open (EO) and with eyes closed (EC). All trials lasted 60 s and were randomized across subjects and conditions. The number of correct subtractions per trial was an index of counting efficiency and the ratio of correct subtractions to total subtractions was an index of accuracy. All conditions collapsed, the efficiency of the cognitive task was significantly lower in PwPD than HE, whilst accuracy was affected to a lower extent. Efficiency significantly improved from sitting to standing in HE under both visual conditions whilst only with EO in PwPD. Accuracy was not affected by posture or vision in either group. We suggest that standing, compared to sitting, increases arousal, thus improving the cognitive performance in HE. Conversely, in PwPD this improvement was present only with vision, possibly due to their greater balance impairment with EC consuming an excess of attentional resources. These findings have implications for balance control and the risk of falling in PwPD in the absence of visual cues.

The effects of standard and modified LSVT BIG therapy protocols on balance and gait in Parkinson's disease: A randomized controlled trial.

Lee Silverman voice treatment (LSVT) BIG is an exercise program developed for patients with Parkinson's disease (PwPD), consisting of sets of exercises performed for 4 consecutive days a week for 4 weeks. However, the standard protocol suggests a treatment frequency difficult to follow for most patients who have difficulties reaching rehabilitation clinics. Our aim was to compare the standard LSVT BIG protocol with a modified LSVT (m-LSVT) BIG protocol (twice a week in the clinic for 4 weeks and twice a week at home for 4 weeks). In this randomized controlled trial, 16 PwPD (aged 18-80 years, Hoehn and Yahr stages I-III) were recruited into two groups. The LSVT group received standard LSVT BIG training (four times per week for 4 weeks at the clinic). The other group was given m-LSVT BIG exercises, but unlike the LSVT group, the m-LSVT group exercised twice a week at the clinic and twice a week at home for 4 weeks. The Berg Balance Scale was used to assess functional balance. Biodex Balance System was used to assess laboratory balance measures. Timed Up and Go test and G-Walk sensor system were used to assess functional mobility and spatiotemporal gait analysis. Significant group-by-time interactions on the eyes open-firm surface score of the modified clinical test of sensory integration of balance (F=10.138, p=.007) and gait cycle symmetry index (F=10.470, p=.010) were found to be in favor of the LSVT group. Additionally, post hoc analyses revealed that both groups significantly improved postural stability, gait speed, motor symptoms, and functional mobility (p<.05). The results revealed the beneficial effects of the modified protocol on balance and gait in PwPD, as well as the superiority of the standard LSVT BIG protocol. The m-LSVT BIG protocol may be an effective intervention method, especially for PwPD who have difficulty adapting to the treatment frequency of the standard protocol.

Vertical Ground Reaction Forces in Parkinson's Disease: A Speed-Matched Comparative Analysis with Healthy Subjects.

This study aimed to investigate and compare the vertical Ground Reaction Forces (vGRFs) of patients with Parkinson's Disease (PwPD) and healthy subjects (HS) when the confounding effect of walking speed was absent. Therefore, eighteen PwPD and eighteen age- and linear walking speed-matched HS were recruited. Using plantar pressure insoles, participants walked along linear and curvilinear paths at self-selected speeds. Interestingly, PwPD exhibited similar walking speed to HS during curvilinear trajectories (p = 0.48) and similar vGRF during both linear and curvilinear paths. In both groups, vGRF at initial contact and terminal stance was higher during linear walking, while vGRF at mid-stance was higher in curvilinear trajectories. Similarly, the time to peak vGRF at each phase showed no significant group differences. The vGRF timing variability was different between the two groups, particularly at terminal stance (p < 0.001). In conclusion, PwPD and HS showed similar modifications in vGRF and a similar reduction in gait speed during curvilinear paths when matched for linear walking speed. This emphasized the importance of considering walking speed when assessing gait dynamics in PwPD. This study also suggests the possibility of the variability of specific temporal measures in differentiating the gait patterns of PwPD versus those of HS, even in the early stages of the disease.

Relationship Between Sleep Quality and Constipation Severity in Patients With Parkinson Disease: A Cross-sectional Study.

BACKGROUND: Constipation in patients with Parkinson disease (PD) adversely affects motor symptoms, making defecation management critical. Sleep disturbance is another common complaint in patients with PD (PWP). Associations between sleep disturbances and constipation have been reported in recent studies on PD. If improving sleep quality is useful for managing constipation in PWP, it might serve as a new method of constipation management that is less physically and mentally distressing than laxatives. This study aimed to examine the relationship between sleep quality and constipation severity in PWP. METHODS: We administered a questionnaire on sleep and constipation to 1048 PWP. Constipation severity was assessed using Constipation Assessment Scale Japanese version 2 (CAS). General sleep quality was estimated using the Japanese versions of the Pittsburgh Sleep Quality Index (PSQI) and Athens Insomnia Scale. Sleep quality due to PD-specific nighttime problems was estimated using the Parkinson's Disease Sleep Scale-2 Japanese version (PDSS-2). We conducted a multiple regression analysis using the forced entry method to identify the variables that influenced CAS. RESULTS: We analyzed 350 PWP. Overall, 94.9% of PWP had constipation symptoms. The percentages of PWP with poor sleep were as follows: PSQI, 74.7%; Athens Insomnia Scale, 69.8%; and PDSS-2, 73.8%. Furthermore, 17.6% of the patients with constipation and 35.3% with sleep problems did not consult a healthcare provider. Multivariate analysis revealed that CAS was significantly associated only with PDSS-2 (standardized partial regression coefficient, 0.217; 95% confidence interval, 0.030-0.111). CONCLUSION: Poor sleep quality, related to PD-specific nighttime problems, was found be associated with worsening constipation severity. Nursing activities that help PWP with PD-specific nighttime problems have a more comfortable night's sleep would be key to alleviating constipation severity.

Association between physical activity and health literacy in patients with Parkinson’s disease: an online web survey

BackgroundFor patients with Parkinson's disease (PwPD), promotion of habitual physical activity (PA) assists in the prevention of disease progression. Patients' health literacy (HL) is integral for meeting PA standards and turning it into a habit. This study evaluated the association between PA level and each HL domain in PwPD.MethodsOnline web-based assessment instruments and self-administered questionnaires, including the PA Questionnaire (IPAQ) Short Form and the Functional, Communicative, and Critical Health Literacy (FCCHL) scale, were used to assess PA levels and health literacy domains of PwPD.ResultsThe mean age of PwPD (n = 114) was 65.9 (SD = 11.6) years; 59.6% female, and the mean duration of disease was 6.4 (SD = 5.1) years. Of participants, 47.4% met the recommended criteria for PA. When comparing each HL domain by PA level, participants with lower PA had significantly lower critical HL (p = 0.03). Logistic regression analysis revealed that PA level correlated with critical HL (OR = 2.46; 95% CI = 1.16–5.19; p = 0.02).ConclusionsAdherence to recommended PA standards was associated with critical HL, but not other HL domains. Proactive attitudes to critically evaluate and utilize as well as understand health information may positively influence the promotion of PA.

A Review of Artificial Intelligence-Based Gait Evaluation and Rehabilitation in Parkinson's Disease.

Parkinson's disease (PD) is a long-term degenerative disease of the central nervous system that affects both motor and non-motor functions. In most cases, symptoms develop gradually, with non-motor symptoms increasing in frequency as the condition progresses. Tremors, stiffness, slow movements, and difficulty walking are some of the early symptoms. There may be problems with cognition, behavior, sleep, and thinking. Dementia caused by PD becomes more common as the disease progresses. The development of PD is linked tocertain sequences of motion thateventuallycontribute to diminished function. Patients with Parkinson's disease (PWPD) have a sluggish, scattered gait that is accompanied by intermittent freezing of gait (FOG), in which efficient heading briefly pauses. In individuals with severe PD, FOGis a neurological deficit that is related to falls and has an unfavorable impact on the patient's standardof living. Artificial intelligence (AI) and ambient intelligence (AmI) are inextricably linked as intelligence is theability to gain new information and employ it in novel contexts. The ambienceis what accompanies us, while artificialrepresents something developed by humans. Wearable technologies are being designed to recognize FOG and support patients in the beginning to walk again via periodic cueing. The articleproposes a unique automated approach for action description that utilizes AI to carry out anon-intrusive, markerless evaluation in real-time and with full robotics. This computerized method accelerates detection and safeguards from human error. Despite significant improvements brought about by the advent of novel technologies, the available assessment platforms still fail to strike the ideal equilibrium among expenditure, diagnostic precision, velocity, and simplicity. The value of the recommended approach can be seen through a comparison of the gait parameters collected by each of the motion-tracking gadgets.

Parkinson's Disease-related Pains are Not Equal: Clinical, Somatosensory and Cortical Excitability Findings in Individuals With Nociceptive Pain

Chronic pain is a frequent and burdensome nonmotor symptom of Parkinson's disease (PD). PD-related chronic pain can be classified as nociceptive, neuropathic, or nociplastic, the former being the most frequent subtype. However, differences in neurophysiologic profiles between these pain subtypes, and their potential prognostic and therapeutic implications have not been explored yet. This is a cross-sectional study on patients with PD (PwP)-related chronic pain (ie, started with or was aggravated by PD). Subjects were assessed for clinical and pain characteristics through questionnaires and underwent quantitative sensory tests and motor corticospinal excitability (CE) evaluations. Data were then compared between individuals with nociceptive and non-nociceptive (ie, neuropathic or nociplastic) pains. Thirty-five patients were included (51.4% male, 55.7 ± 11.0 years old), 20 of which had nociceptive pain. Patients with nociceptive PD-related pain had lower warm detection threshold (WDT, 33.34 ± 1.39 vs 34.34 ± 1.72, P = .019) and mechanical detection threshold (MDT, 2.55 ± 1.54 vs 3.86 ± .97, P = .007) compared to those with non-nociceptive pains. They also presented a higher proportion of low rest motor threshold values than the non-nociceptive pain ones (64.7% vs 26.6%, P = .048). In non-nociceptive pain patients, there was a negative correlation between WDT and non-motor symptoms scores (r = −.612, P = .045) and a positive correlation between MDT and average pain intensity (r = .629, P = .038), along with neuropathic pain symptom scores (r = .604, P = .049). It is possible to conclude that PD-related chronic pain subtypes have distinctive somatosensory and CE profiles. These preliminary data may help better frame previous contradictory findings in PwP and may have implications for future trial designs aiming at developing individually-tailored therapies. PerspectiveThis work showed that PwP-related nociceptive chronic pain may have distinctive somatosensory and CE profiles than those with non-nociceptive pain subtypes. These data may help shed light on previous contradictory findings in PwP and guide future trials aiming at developing individually-tailored management strategies.

Neuroinflammation and Mitochondrial Dysfunction in Parkinson's Disease: Connecting Neuroimaging with Pathophysiology.

There is a pressing need for disease-modifying therapies in patients suffering from neurodegenerative diseases, including Parkinson's disease (PD). However, these disorders face unique challenges in clinical trial designs to assess the neuroprotective properties of potential drug candidates. One of these challenges relates to the often unknown individual disease mechanisms that would, however, be relevant for targeted treatment strategies. Neuroinflammation and mitochondrial dysfunction are two proposed pathophysiological hallmarks and are considered to be highly interconnected in PD. Innovative neuroimaging methods can potentially help to gain deeper insights into one's predominant disease mechanisms, can facilitate patient stratification in clinical trials, and could potentially map treatment responses. This review aims to highlight the role of neuroinflammation and mitochondrial dysfunction in patients with PD (PwPD). We will specifically introduce different neuroimaging modalities, their respective technical hurdles and challenges, and their implementation into clinical practice. We will gather preliminary evidence for their potential use in PD research and discuss opportunities for future clinical trials.

New‑onset non‑motor symptoms in patients with Parkinson's disease and post‑COVID‑19 syndrome: A prospective cross‑sectional study.

The clinical range of post-coronavirus disease 2019 (COVID-19) symptoms in patients with Parkinson's disease (PD) has not yet been thoroughly characterized, with the exception of a few small case studies. The aim of the present study was to investigate the motor and non-motor progression of patients with PD (PWP) and post-COVID-19 syndrome (PCS) at baseline and at 6 months after infection with COVID-19. A cross-sectional prospective study of 38 PWP+/PCS+ and 20 PWP+/PCS- matched for age, sex and disease duration was conducted. All patients were assessed at baseline and at 6 months using a structured clinicodemographic questionnaire, the Unified Parkinson's Disease Rating Scale Part III (the UPDRS III), the Montreal Cognitive Assessment, the Hoehn and Yahr scale, the Geriatric Depression Scale and the levodopa equivalent daily dose (LEDD). There was a statistically significant difference in the LEDD (P=0.039) and UPDRS III (P=0.001) at baseline and at 6 months after infection with COVID-19 between the PWP with PCS groups. The most common non-motor PCS symptoms were anosmia/hyposmia, sore throat, dysgeusia and skin rashes. There was no statistically significant difference in demographics or specific scores between the two groups, indicating that no prognostic factor for PCS in PWP could be identified. The novelty of the present study is that it suggests the new onset of non-motor PCS symptoms of PWP with a mild to moderate stage.

Language impairment in Parkinson's disease: fMRI study of sentence reading comprehension.

Parkinson's disease (PD) affects the language processes, with a significant impact on the patients' daily communication. We aimed to describe specific alterations in the comprehension of syntactically complex sentences in patients with PD (PwPD) as compared to healthy controls (HC) and to identify the neural underpinnings of these deficits using a functional connectivity analysis of the striatum. A total of 20 patients PwPD and 15 HC participated in the fMRI study. We analyzed their performance of a Test of sentence comprehension (ToSC) adjusted for fMRI. A task-dependent functional connectivity analysis of the striatum was conducted using the psychophysiological interaction method (PPI). On the behavioral level, the PwPD scored significantly lower (mean ± sd: 77.3 ± 12.6) in the total ToSC score than the HC did (mean ± sd: 86.6 ± 8.0), p = 0.02, and the difference was also significant specifically for sentences with a non-canonical word order (PD-mean ± sd: 69.9 ± 14.1, HC-mean ± sd: 80.2 ± 11.5, p = 0.04). Using PPI, we found a statistically significant difference between the PwPD and the HC in connectivity from the right striatum to the supplementary motor area [SMA, (4 8 53)] for non-canonical sentences. This PPI connectivity was negatively correlated with the ToSC accuracy of non-canonical sentences in the PwPD. Our results showed disturbed sentence reading comprehension in the PwPD with altered task-dependent functional connectivity from the right striatum to the SMA, which supports the synchronization of the temporal and sequential aspects of language processing. The study revealed that subcortical-cortical networks (striatal-frontal loop) in PwPD are compromised, leading to impaired comprehension of syntactically complex sentences.

The effect of task-oriented circuit training-based telerehabilitation on upper extremity motor functions in patients with Parkinson's disease: A randomized controlled trial

IntroductionUpper extremity functions are impaired in patients with Parkinson's disease (PwPD), which leads to difficulties in activities of daily living (ADL), such as reaching or handwriting. The aim of this study was to investigate the effectiveness of task-oriented circuit training-based telerehabilitation (TOCT-TR) on the upper extremity motor function in PwPD. MethodsIn this randomized controlled trial (RCT) 30 PwPD (aged 45–70 years, Hoehn & Yahr stage I-III) were recruited and randomly allocated into two groups. The TOCT-TR group received home training through video sessions three days/week for six weeks. Additionally, both the TOCT-TR group and the control group (CG) underwent home exercises aimed at improving balance, gait, and mobility three days/week for six weeks. The primary outcome measure was upper extremity motor functions measured with the Nine Hole Peg test (9-HPT), the Jebsen Hand Function Test (JHFT), grip strengths, pinch strengths, and the Unified Parkinson's Disease Rating Scale-III (UPDRS-III). Secondary outcome measures included the UPDRS-II and the quality of life (QoL, PDQ-8). ResultsThis study showed significant group-by-time interactions on the 9-HPT (p < 0.001), the JHFT (p < 0.001), grip strengths (p < 0.001), pinch strengths (p ≤ 0.015), and the UPDRS-III (p = 0.007) in favor of the TOCT-TR. Additionally, the UPDRS-II (p < 0.001), and the PDQ-8 (p = 0.005) improved in both groups. ConclusionThis is the first RCT showing that the TOCT-TR improved upper extremity motor functions, ADL, and QoL in PwPD. The TOCT-TR may help improve the upper extremities of PwPD who have difficulties reaching rehabilitation clinics.

Gastrointestinal Motility and Response to Levodopa in Parkinson's Disease: A Proof-of-Concept Study.

Simultaneous measurement of gastrointestinal transit time (GITT) and plasma levodopa concentration (PLC) is crucial to understanding the effect of dysfunctional motility on levodopa response in patients with Parkinson's disease (PwPD). The aim is to determine if altered segmental GITT correlates with clinical response and PLC variability in PwPD. Ten typical and 10 erratic responders ingested the SmartPill (SP) wireless motility capsule. Serial PLC and finger tapping, obtained every 30minutes for 3 hours after SP/levodopa ingestion, evaluated the correlation between GITT, clinical response, and PLC. Glucose breath testing assessed small intestinal bacterial overgrowth (SIBO). GITT was not significantly different in "typical" and "erratic" responders. SIBO was positive in half of the erratic and negative in most typical responders. SP is a feasible technology for assessing GITT in PwPD. A larger study may be able to significantly differentiate/correlate GITT in different segments of the GI tract with response to levodopa. © 2022 International Parkinson and Movement Disorder Society.

Development and Validation of a Fall Questionnaire for Patients with Parkinson's Disease.

BackgroundIn Parkinson's disease, postural instability and falls are of particular socioeconomic relevance. Although effective fall prevention and the prophylaxis of fall‐related injuries depend on low‐threshold symptom monitoring, validated instruments are lacking.ObjectivesTo develop a self‐report questionnaire for the assessment of falls, near falls, fear of falling, fall‐related injuries, and causes of falls for patients with Parkinson's disease (PwPD).MethodsA pool of potential items was generated from a literature review and by discussion in an expert panel. The first version of the Dresden Fall Questionnaire (DREFAQ) was tested in a group of German‐speaking movement disorder specialists as well as PwPD. The resulting 5‐item questionnaire was assessed in a validation cohort of 36 PwPD who documented fall events and near‐fall events in a calendar for 3 months and completed the DREFAQ at the end of the study. The questionnaire was subsequently used in a separate cohort of 46 PwPD to determine test–retest reliability and confirm the factor structure.ResultsThe DREFAQ showed good internal consistency (Cronbach's α = 0.84) and good test–retest reliability (intraclass correlation coefficient, 0.76; 95% confidence interval, 0.60–0.86). The total DREFAQ score showed good concurrent validity with fall events (Spearman's ρ = 0.82) and near‐fall events (Spearman's ρ = 0.78) as determined by fall and near‐fall diaries. Factor analysis revealed a 2‐factor structure composed of near falls with fear of falling and severe falls with injuries.ConclusionsThe DREFAQ is a reliable and valid 5‐item questionnaire for determining the incidence of falls, near falls, fear of falling, fall‐related injuries, and causes of falls in PwPD.

Activity Recognition in Parkinson's Patients from Motion Data Using a CNN Model Trained by Healthy Subjects.

Physical activity recognition in patients with Parkinson's Disease (PwPD) is challenging due to the lack of large-enough and good quality motion data for PwPD. A common approach to this obstacle involves the use of models trained on better quality data from healthy patients. Models can struggle to generalize across these domains due to motor complications affecting the movement patterns in PwPD and differences in sensor axes orientations between data. In this paper, we investigated the generalizability of a deep convolutional neural network (CNN) model trained on a young, healthy population to PD, and the role of data augmentation on alleviating sensor position variability. We used two publicly available healthy datasets - PAMAP2 and MHEALTH. Both datasets had sensor placements on the chest, wrist, and ankle with 9 and 10 subjects, respectively. A private PD dataset was utilized as well. The proposed CNN model was trained on PAMAP2 in k-fold cross-validation based on the number of subjects, with and without data augmentation, and tested directly on MHEALTH and PD data. Without data augmentation, the trained model resulted in 48.16% accuracy on MHEALTH and 0% on the PD data when directly applied with no model adaptation techniques. With data augmentation, the accuracies improved to 87.43% and 44.78%, respectively, indicating that the method compensated for the potential sensor placement variations between data. Clinical Relevance- Wearable sensors and machine learning can provide important information about the activity level of PwPD. This information can be used by the treating physician to make appropriate clinical interventions such as rehabilitation to improve quality of life.

Association of Motor and Nonmotor Symptoms With Health-Related Quality of Life in a Large Online Cohort of People With Parkinson Disease

Background and ObjectivesThere is growing interest in health-related quality of life (HRQOL) as a comprehensive view of the patient's well-being, guiding concept for the treating clinician, and therapeutic trial outcome measure for patients with Parkinson disease (PwPD). The key determinants of HRQOL have not been investigated in large populations of PwPD. Our objective was to evaluate correlates of HRQOL in a large, online cohort of PwPD.MethodsAs part of an ongoing online cohort study, we performed a cross-sectional analysis at enrollment of 23,058 PwPD. We conducted univariate and stepwise multivariate linear regression analyses of HRQOL as measured by the EQ-5D-5L tool. In addition, we performed an interaction analysis to evaluate heterogeneity of the effect of motor symptoms on HRQOL and Spearman correlation analysis to evaluate the association of nonmotor symptoms with HRQOL.ResultsIn the multivariate linear regression model, participants with moderate or severe depression, more severe motor symptoms, and a higher burden of medical comorbidities had the most substantially decreased HRQOL as measured by the EQ index (β −0.11, −0.18, −0.02, −0.01, respectively; p < 0.001 for all). An interaction analysis showed that more severe motor symptoms had a higher effect on individuals with female sex, lower educational level, lower income, more severe depression, or more severe cognitive impairment (p ≤ 0.01 for interaction terms). Neuropsychiatric symptoms and falls had the most negative associations with HRQOL (ρ −0.31 to 0.37; p < 0.0001).DiscussionPotentially treatable motor and nonmotor symptoms, particularly neuropsychiatric symptoms, account for a large amount of the variation in HRQOL in PwPD. Motor symptoms may have differential effects on HRQOL in different demographic and clinical subpopulations, highlighting important areas for future health disparities research. Our findings provide targets for clinician intervention and future research on symptom management to optimize HRQOL in PD.Classification of EvidenceThis study provides Class II evidence that motor and neuropsychiatric symptoms are associated with HRQOL in PwPD.

TDCS application for postural control in Parkinson's disease: Effects are associated with baseline characteristics

IntroductionTranscranial direct current stimulation (tDCS) improves postural response to perturbation in patients with Parkinson's disease (PwPD). However, the influence of baseline characteristics such as clinical/cognitive and postural performance on the response to tDCS remains unclear. ObjectiveTo investigate whether baseline level of postural control (performance during sham condition) and clinical/cognitive characteristics are associated with tDCS-related changes in postural responses to external perturbations in PwPD. MethodsTwenty-four PwPD participated in this study. Clinical assessment included disease severity, disease duration, levodopa equivalent dose and global cognition. Anodal tDCS protocols targeting the primary motor cortex were applied in two separate sessions (at least 2 weeks apart): active (2 mA for 20 min) and sham stimulation. Seven trials with the backward translation of the support base (20 cm/s and 5 cm) were performed after tDCS. Postural outcomes included the recovery time to stable position and onset latency of the medial gastrocnemius (MG). Pearson and Spearman correlation tests were performed. ResultsNo significant correlations were observed between clinical/cognitive characteristics and tDCS-related changes in postural responses. Negative associations were observed between the baseline level of postural control and tDCS-related changes in postural responses for the recovery time (r = −0.657; p < 0.001) and the MG onset latency (rs = −0.539; p = 0.007). PwPD with worse baseline postural control demonstrated greater improvement after active stimulation. ConclusionsFindings suggest that tDCS-related effects on postural response to perturbation are related to the baseline level of postural control, but not to clinical characteristics in PwPD. Those with worse baseline postural control responded better to tDCS.

Dependence of the Parkinson's disease clinical picture on the season

In temperate climates, many factors that may influence function in Parkinson's disease (PD) vary according to season [Ronald B Postuma, 2005]. Goal of our research was the determination of connection between symptoms in patients with Parkinson's disease (PwPD) and seasons.

A Review of Voltammetric Methods for Determination of Dopamine Agonists

Background: Dopamine agonists are useful drugs for the management of patients with Parkinson's disease in the early and later stages of the disease. Parkinson's disease is a progressive neurodegenerative disease that primarily affects dopamine-producing nerve cells in the brain. They bind to dopamine receptors in nerve cells that regulate body movement and motor function. Electroanalytical methods are used in medicinal, clinical and pharmaceutical research. Voltammetry is one of the most commonly used electroanalytical methods. This review aims to gather and discuss studies of voltammetric methods used in determination of dopamine agonists. Methods: This review includes the use of various voltammetric methods for determination studies of dopamine agonists from pharmaceutical dosage forms and biological samples. These studies were examined in terms of used voltammetric method or methods, working electrode, buffer, pH and validation parameters. Results: Cabergoline, pramipexole, and ropinirole have more studies, while bromocriptine and apomorphine have fewer studies in the literature. Differential pulse voltammetry and square wave voltammetry methods were the most applied methods for the determination of dopamine agonist drugs from pharmaceuticals and biological samples. But, stripping, cyclic and linear sweep voltammetry methods are less applied methods. In these studies, a lot of modified electrodes were developed and used to analyse dopamine agonists. Conclusion: The voltammetric methods provide the determination of therapeutic agents and/or their metabolites in clinical samples at extremely low concentrations without the necessity for the sample pre-treatment or time consuming extraction steps. Also, the modified electrodes and validated voltammetric methods provide good stability, repeatability, reproducibility and high recovery for the analysis of the analyte.