Anxiety provokes balance deficits that are selectively dopa-responsive in Parkinson’s disease

Differentiation in theta and gamma activation in weight-shifting learning between people with parkinson's disease of different anxiety severities

Anxiety and postural control deficits may be related in people with Parkinson's disease (PwPD). However, the association between anxiety levels and weight-shifting control remains ambiguous. This study investigated whether 1) weight-shifting control differed between PwPD with and without anxiety, and 2) the learning effect of weight-shifting differed between the two populations. Additionally, we evaluated cortical activities to investigate neural mechanisms underlying weight-shifting control. Twenty-eight PwPD (14 anxiety, 14 nonanxiety) participated in a 5-day weight-shifting study by coupling the bearing weight of their more-affected leg to a sinusoidal target at 0.25 Hz. We tested the weight-shifting control on day 1 (pretest), day 3 (posttest), and day 5 (retention test) with a learning session on day 3. The error and jerk of weight-shifting trajectory and the theta and gamma powers of electroencephalography in prefrontal, frontal, sensorimotor and parietal-occipital areas were measured. At the pretest, the anxiety group showed larger error and smaller jerk of weight-shifting with greater prefrontal theta, frontal gamma, and sensorimotor gamma powers than the nonanxiety group. Anxiety intensity was correlated positively with weight-shifting error and theta power but negatively with weight-shifting jerk. Reduced weight-shifting error with increased theta power after weight-shifting learning was observed in the nonanxiety group. However, the anxiety group showed decreased gamma power after weight-shifting learning without behavior change. Our findings suggest differential weight-shifting control and associated cortical activation between PwPD with and without anxiety. In addition, anxiety would deteriorate weight-shifting control and hinder weight-shifting learning benefits in PwPD, leading to less weight-shifting accuracy and correction.

Role of virtual reality in examining the effect of fear of falling (FOF) on postural stability in individuals without and with Parkinson's disease in Egypt: a mixed-methods feasibility study protocol

BACKGROUND

Falls are common in older people and individuals with neurological conditions. Parkinson's disease (PD) is known for postural instability causing mobility disabilities, falls and reduced quality of life. The fear of falling (FOF), a natural response to unstable balance, can worsen postural control problems. Evaluating FOF relies largely on affected persons' subjective accounts due to limited objective assessment methods available. The aim of this mixed-methods feasibility study is to develop an assessment method for FOF while in motion and walking within virtual environments. This study will assess a range of FOF-related responses, including cognitive factors, neuromuscular response and postural stability.

METHODS AND ANALYSIS

This feasibility study will consist of four phases: the first two phases will include people without PD, while the other two will include people diagnosed with PD. Participants will be assessed for direct and indirect responses to real life, as well as virtual environment walking scenarios that may induce FOF. Data from questionnaires, different neurophysiological assessments, movement and gait parameters, alongside evaluations of usability and acceptability, will be collected. Semistructured interviews involving both participants and research assistants shall take place to elicit their experiences throughout different phases of the assessments undertaken. Demographic data, the scores of assessment scales, as well as feasibility, usability and acceptability of the measurement methods, will be illustrated via descriptive statistics. Movement and gait outcomes, together with neurophysiological data, will be extracted and calculated. Exploring relationships between different factors in the study will be achieved using a regression model. Thematic analysis will be the approach used to manage qualitative data.

ETHICS AND DISSEMINATION

This feasibility study was approved by the Ethics Committee of the Faculty of Physical Therapy, Kafr El Sheikh University, Egypt (number: P.T/NEUR/3/2023/46). The results of this study will be published in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT05931692).

Baduanjin is Better Balance Training Compared to Walking: A Cross-Sectional Study Based on Center of Gravity Trajectories

BACKGROUND

 It has already been demonstrated by previous studies that Baduanjin training can improve the body's balance. However, its biomechanical mechanism remains unknown. Center of gravity (COG) trajectory analysis is an essential biomechanical test to explore the balance ability of the human body. Previous studies have not used the COG trajectory analysis technique to research Baduanjin training. The study utilizes COG trajectory analysis to analyze the trajectory of COG during Baduanjin training and compare it with that of walking, which is a common exercise for improving balance and aerobic ability, to determine if Baduanjin exercises affect the COG more than walking.

MATERIALS AND METHODS

 Eight healthy female college students performed the walking and the eight forms of Baduanjin, a total of nine motions. The lower body kinematics were captured by the Vicon Motion Capture and Analysis System, while the kinetic data were acquired by the Kistler 3D Force Platform. The data were imported into Visual 3D to process the trajectory of the COG displacement amplitude, velocity, and acceleration of each motion. The COG horizontal envelope areas were calculated by Origin 9.0 Software (Origin Lab, Northampton, Massachusetts, USA) .

RESULTS

Specific motions of Baduanjin provided significantly higher COG displacement amplitude, velocities, and acceleration training than walking. The F2 and F5 motions could provide a larger COG horizontal envelope area than walking. On the x-axis, F2 provided a greater COG displacement amplitude than walking, F1, F2, and F5 provided greater velocities, while all the motions provided greater accelerations. On the y-axis, all the motions except F2 provided greater COG displacement velocities and accelerations than walking. On the z-axis, F1-7 provided a greater COG displacement amplitude than walking, all the motions provided greater velocities, while all the motions except F2 provided greater accelerations.

CONCLUSION

Baduanjin training provides a more intense COG perturbation than walking, which may be a more challenging balance training than walking.

The effect of physical exercise on anxiety in people with parkinson’s disease: A systematic review of randomized control trials

BACKGROUND Anxiety is a prominent disabling non-motor neuropsychiatric complication of Parkinson’s disease (PD). Pharmacological treatments for PD and anxiety have drug interactions and negative side effects. Therefore, non-pharmacological interventions such as exercise has been proposed to reduce anxiety in people with PD (PwP). OBJECTIVE This systematic review aimed to explore the relationship between physical exercise and anxiety in PwP. METHOD Four databases (PubMed, Embase, Scopus, Ebscohost) were searched without date restrictions. English randomized control trials (RCT) including adults with PD, exposed to physical exercise interventions with anxiety as an outcome variable, were included. Quality was assessed by means of an adapted 9-point PEDro scale. RESULTS Five of the identified 5547 studies met the inclusion criteria. Sample size ranged between 11–152 participants, totaling 328 participants with majority being male. PD stage ranged from early to moderate, with disease duration ranged between 2.9 and 8.0 years. All studies measured anxiety at baseline and post-intervention. On average studies scored 7/9 (76%) on the PEDro scale. CONCLUSION There is insufficient evidence to support or refute the effect of exercise on anxiety in PwP due to noted limitations of included studies. There is an urgent need for high-quality RCTs on physical exercise and anxiety in PwP.

Synergistic effect between quinpirole and L-NAME as well as sulpiride and L-arginine on the modulation of anxiety and memory processes in the 6-OHDA mouse model of Parkinson's disease: An isobologram analysis

We evaluated interactions between dopamine D2 receptor and nitric oxide (NO) actions on the regulation of anxiety and memory in the 6-hydroxydopamine (6-OHDA) mouse model of Parkinson's disease (PD). A unilateral guide cannula was stereotaxically implanted over the right striatum. Elevated plus-maze test (EPM) test-retest protocol was employed to evaluate anxiety and memory in mice. The results revealed that injection of L-NAME (9 mg/kg) induced anxiolytic and amnesic effects, while L-arginine (9 mg/kg) produced anxiogenic and memory-improvement effects in the 6-OHDA mouse model of PD. Administration of sulpiride (20 mg/kg) induced anxiogenic and memory-improvement effects, whereas quinpirole (20 mg/kg) caused anxiolytic and amnesic effects in PD mice. Co-injection of sulpiride (5, 10, and 20 mg/kg) plus L-NAME (3 mg/kg) induced anxiolytic and amnesic effects. Co-injection of sulpiride (20 mg/kg) plus L-arginine (3 mg/kg) induced anxiogenic and memory-improvement effects. Co-administrations of quinpirole (20 mg/kg) and L-NAME (3 mg/kg) induced anxiolytic effect, but co-administration of quinpirole (20 mg/kg) plus L-arginine (3 mg/kg) caused anxiogenic and memory-improvement effects. The isobologram analysis revealed that there is a synergistic effect between sulpiride and L-arginine as well as quinpirole and L-NAME upon induction of anxiogenic and anxiolytic effects, respectively in PD mice. Our results suggested: (1) NO and dopamine D2 receptor mechanisms affect anxiety and memory in PD mice; (2) L-NAME reversed anxiogenic and memory-improvement effect induced by sulpiride; (3) Anxiolytic and amnesic effects induced by quinpirole reversed by L-arginine; (4) There is a synergistic effect between dopamine D2 receptor and NO systems on the modulation of anxiety and memory.

Balance response to levodopa predicts balance improvement after bilateral subthalamic nucleus deep brain stimulation in Parkinson's disease

The effect of subthalamic nucleus deep brain stimulation (STN-DBS) on balance function in patients with Parkinson’s disease (PD) and the potential outcome predictive factors remains unclear. We retrospectively included 261 PD patients who underwent STN-DBS and finished the 1-month follow-up (M1) assessment in the explorative set for identifying postoperative balance change predictors, and 111 patients who finished both the M1 and 12-month follow-up (M12) assessment in the validation set for verifying the identified factors. Motor and balance improvement were evaluated through the UPDRS-III and the Berg balance scale (BBS) and pull test (PT), respectively. Candidate predictors of balance improvement included age, disease duration, motor subtypes, baseline severity of PD, cognitive status, motor and balance response to levodopa, and stimulation parameters. In the off-medication condition, STN-DBS significantly improved BBS and PT performance in both the M1 and M12, in both datasets. While in the on-medication condition, no significant balance improvement was observed. Higher preoperative BBS response to levodopa was significantly associated with larger postoperative off-medication, but not on-medication, BBS (p < 0.001) and PT (p < 0.001) improvement in both the M1 and M12. BBS subitems 8, 9, 11, 13, and 14 were the major contributors to the prediction of balance improvement after STN-DBS. STN-DBS improves short-term off-medication, but not on-medication, balance function assessed through BBS and PT. Preoperative BBS response to levodopa best predicts postoperative off-medication balance improvement. For patients who manifested severe balance problems, a levodopa challenge test on BBS or the short version of BBS is recommended.

The Relationship Between Anxiety Disorders and Parkinson's Disease: Clinical and Therapeutic Issues

PURPOSE OF REVIEW

This paper seeks to describe anxiety's different symptomatologic presentations in Parkinson's disease (PD), its longitudinal course and predictors, as well as its motor and non-motor correlates. It also reviews the available screening tools and different treatment modalities.

RECENT FINDINGS

In PD, longitudinal predictors of anxiety are mostly non-motor non-dopaminergic symptoms. The longitudinal course of anxiety is mainly a stable one. The Parkinson Anxiety Scale and the Geriatric Anxiety Scale are the 2 recommended screening tools. A third of PD patients suffer from an anxiety disorder at any time point. It can precede or follow PD motor symptoms. Anxiety is associated with demographic, disease-related motor and non-motor features. There is a lack of studies evaluating psychotropic treatment of anxiety in PD. Adjustment of dopaminergic treatment is indicated when anxiety is associated with motor fluctuations. DBS can be useful as well as CBT and body-mind interventions.

Mood and emotional disorders associated with parkinsonism, Huntington disease, and other movement disorders

This chapter provides a review of mood, emotional disorders, and emotion processing deficits associated with diseases that cause movement disorders, including Parkinson's disease, Lewy body dementia, multiple system atrophy, progressive supranuclear palsy, corticobasal degeneration, frontotemporal dementia with parkinsonism, Huntington's disease, essential tremor, dystonia, and tardive dyskinesia. For each disorder, a clinical description of the common signs and symptoms, disease progression, and epidemiology is provided. Then the mood and emotional disorders associated with each of these diseases are described and discussed in terms of clinical presentation, incidence, prevalence, and alterations in quality of life. Alterations of emotion communication, such as affective speech prosody and facial emotional expression, associated with these disorders are also discussed. In addition, if applicable, deficits in gestural and lexical/verbal emotion are reviewed. Throughout the chapter, the relationships among mood and emotional disorders, alterations of emotional experiences, social communication, and quality of life, as well as treatment, are emphasized.

Sensory focused exercise improves anxiety in Parkinson's disease: A randomized controlled trial

Anxiety has been implicated as one of the greatest influences on quality of life in Parkinson’s disease (PD). The etiology of anxiety is unclear, although previous work suggests that anxiety may be linked to sensory deficits that cause uncertainty in movement. Thus, the current study examined whether focusing attention on sensory feedback during goal-based exercise has the potential to provide benefits to anxiety in PD. Thirty-five participants with PD were randomized to either a Sensory Attention Focused Exercise (SAFEx) (i.e. internal focus of attention, n = 18) or Sham Exercise control (i.e. external focus of attention, n = 17) and completed 33 one-hour attention-based exercise sessions over 11-weeks. Before and after the program (pre and post), participants completed the Parkinson Anxiety Scale (PAS) questionnaire. The PAS includes three anxiety sections: persistent, episodic, and avoidance. Changes in the total PAS score and within each section of the PAS were subjected to two-factor mixed repeated measures ANCOVA. Significant group by time interactions demonstrated that from pre to post, total PAS scores (p = 0.007) and episodic anxiety scores (p = 0.010) significantly decreased in the SAFEx group only (ΔTotal PAS = -5.2, F_(1,27) = 5.41, p = 0.028, η_p² = 0.17; ΔEpisodic Score = -1.8, F_(1,27) = 6.89, p = 0.014, η_p² = 0.20). In conclusion, focusing attention on sensory feedback while completing goal-based exercises may provide significant benefits to improving anxiety in PD. As such, sensory attention focused exercise may be a critical adjunct therapy for improving anxiety, and ultimately quality of life in people with PD.

The effects of anxiety and external attentional focus on postural control in patients with Parkinson's disease

Background

Although anxiety is a common non-motor outcome of Parkinson's disease (PD) affecting 40% of patients, little attention has been paid so far to its effects on balance impairment and postural control. Improvement of postural control through focusing on the environment (i.e. external focus) has been reported, but the role of anxiety, as a confounding variable, remains unclear.

Objectives

This study aimed to investigate the influence of anxiety and attentional focus instruction on the standing postural control of PD patients.

Methods

Thirty-four patients with PD (17 with high anxiety (HA-PD) and 17 with low anxiety (LA-PD)), as well as 17 gender- and age-matched healthy control subjects (HC) participated in the study. Postural control was evaluated using a combination of two levels of postural difficulty (standing on a rigid force plate surface with open eyes (RO) and standing on a foam surface with open eyes (FO)), as well as three attentional focus instructions (internal, external and no focus).

Results

Only the HA-PD group demonstrated significant postural control impairment as compared to the control, as indicated by significantly greater postural sway measures. Moreover, external focus significantly reduced postural sway in all participants especially during the FO condition.

Conclusion

The results of the current study provide evidence that anxiety influences balance control and postural stability in patients with PD, particularly those with high levels of anxiety. The results also confirmed that external focus is a potential strategy that significantly improves the postural control of these patients. Further investigation of clinical applicability is warranted towards developing effective therapeutic and rehabilitative treatment plans.