A common cognitive profile in elderly fallers and in patients with Parkinson's disease: the prominence of impaired executive function and attention

Impaired Standing Balance in Older Adults with Cognitive Impairment after a Severe Fall

INTRODUCTION

Fall-related sequelae as well as balance and gait impairments are more pronounced in older adults who are cognitively impaired (OACI) compared to older adults who are cognitively healthy (OACH). Evidence is scarce about differences in standing balance and gait in OACH and OACI after a fall, even though these are major risks for recurrent falls. Thus, the aim of this study was to investigate early impairments in gait and balance, by adding inertial measurement units (IMUs) to a functional performance test in OACH and OACI after a severe fall with a presentation to the emergency department (ED) and immediate discharge.

METHODS

The study sample was stratified into participants with and without probable cognitive impairment using the result of the Montreal Cognitive Assessment total score (maximum of 30 points). The cutoff for probable cognitive impairment was set at ≤ 24. Standing balance and gait parameters were measured using three IMUs in n = 69 OACH (72.0 ± 8.2 years) and n = 76 OACI (78.7 ± 8.1 years). Data were collected at participants' homes as part of a comprehensive geriatric assessment in the "SeFallED" study within 4 weeks after presentation to the ED after a severe fall (German Clinical Trials Register ID: 00025949). ANCOVA was used for statistical analysis, adjusted for age.

RESULTS

The data indicated significantly more sway for OACI compared to OACH during balance tasks, whereas no differences in gait behavior were found. In detail, differences in standing balance were revealed for mean velocity (m/s) during parallel stance with eyes open (ηp2 = 0.190, p < 0.001) and eyes closed on a balance cushion (ηp2 = 0.059, p = 0.029), as well as during tandem stance (ηp2 = 0.034, p = 0.044) between OACI and OACH. Further differences between the two groups were detected for path length (m/s2) during parallel stance with eyes open (ηp2 = 0.144, p < 0.001) and eyes closed (ηp2 = 0.044, p < 0.027) and for range (m/s2) during tandem (ηp2 = 0.036, p = 0.036) and parallel stance with eyes closed (ηp2 = 0.045, p = 0.032).

CONCLUSION

Even though both groups have experienced a severe fall with presentation to the ED in the preceding 4 weeks, balance control among OACI indicated a higher fall risk than among OACH. Therefore, effective secondary fall prevention efforts have to be established, particularly for OACI.

Immediate fall prevention: the missing key to a comprehensive solution for falling hazard in older adults

The world is witnessing an unprecedented demographic shift due to increased life expectancy and declining birth rates. By 2050, 20% of the global population will be over 60, presenting significant challenges like a shortage of caregivers, maintaining health and independence, and funding extended retirement. The technology that caters to the needs of older adults and their caregivers is the most promising candidate to tackle these issues. Although multiple companies and startups offer various aging solutions, preventive technology, which could prevent trauma, is not a big part of it. Trauma is the leading cause of morbidity, disability, and mortality in older adults, and statistics constitute traumatic fall accidents as its leading cause. Therefore, an immediate preventive technology that anticipates an accident on time and prevents it must be the first response to this hazard category to decrease the gap between life expectancy and the health/wellness expectancy of older adults. The article outlines the challenges of the upcoming aging crisis and introduces falls as one major challenge. After that, falls and their mechanisms are investigated, highlighting the cognitive functions and their relation to falls. Moreover, since understanding predictive cognitive mechanisms is critical to an effective prediction-interception design, they are discussed in more detail, signifying the role of cognitive decline in balance maintenance. Furthermore, the landscape of available solutions for falling and its shortcomings is inspected. Finally, immediate fall prevention, the missing part of a wholesome solution, and its barriers are introduced, and some promising methodologies are proposed.

Effects of 12-week aerobic exercise with different frequencies on executive function in preschool children: a cluster randomized controlled trial

OBJECTIVE

To explore the effects of a 12-week aerobic exercise program with different frequencies on executive functions (EFs) in preschool children.

METHOD

Four kindergartens, comprising 126 preschool children in Shanghai, were enrolled in this 12-week cluster randomized controlled trial with a 12-week follow-up period. Kindergartens were allocated to high-frequency (three times a week) or low-frequency (once a week) exercise groups using stratified block randomization. Three core sub-EFs, including inhibition, working memory, and cognitive flexibility, were assessed at baseline, post-intervention, and the 12-week follow-up.

RESULTS

Compared to baseline, both groups showed significant improvements in inhibition and working memory after the intervention and at the 12-week follow-up. However, only the high-frequency exercise group demonstrated a significant improvement in cognitive flexibility after the follow-up period. Nonetheless, there were no significant differences in the core sub-functions of EFs between the two groups at the end of the intervention or the follow-up periods.

CONCLUSION

A 12-week aerobic exercise of three times a week was insufficient to significantly improve EFs in preschool children compared to once a week. Future studies are needed to examine the dose-response relationship of aerobic exercise on EFs and to verify the effects of different exercise modalities on EFs in preschool children.

Balance telerehabilitation and wearable technology for people with Parkinson's disease (TelePD trial)

BACKGROUND

Balance impairments, that lead to falls, are one of the main symptoms of Parkinson's disease (PD). Telerehabilitation is becoming more common for people with PD; however, balance is particularly challenging to assess and treat virtually. The feasibility and efficacy of virtual assessment and virtual treatment of balance in people with PD are unknown. The present study protocol has three aims: I) to determine if a virtual balance and gait assessment (instrumented L-shape mobility test) with wearable sensors can predict a gold-standard, in-person clinical assessment of balance, the Mini Balance Evaluation Systems Test (Mini-BESTest); II) to explore the effects of 12 sessions of balance telerehabilitation and unsupervised home exercises on balance, gait, executive function, and clinical scales; and III) to explore if improvements after balance telerehabilitation transfer to daily-life mobility, as measured by instrumented socks with inertial sensors worn for 7 days.

METHODS

The TelePD Trial is a prospective, single-center, parallel-group, single-blind, pilot, randomized, controlled trial. This trial will enroll 80 eligible people with PD. Participants will be randomized at a 1:1 ratio into receiving home-based balance exercises in either: 1) balance telerehabilitation (experimental group, n = 40) or 2) unsupervised exercises (control group, n = 40). Both groups will perform 12 sessions of exercise at home that are 60 min long. The primary outcome will be Mini-BESTest. The secondary outcomes will be upper and lower body gait metrics from a prescribed task (instrumented L-shape mobility test); daily-life mobility measures over 7 days with wearable sensors in socks, instrumented executive function tests, and clinical scales. Baseline testing and 7 days of daily-life mobility measurement will occur before and after the intervention period.

CONCLUSION

The TelePD Trial will be the first to explore the usefulness of using wearable sensor-based measures of balance and gait remotely to assess balance, the feasibility and efficacy of balance telerehabilitation in people with PD, and the translation of balance improvements after telerehabilitation to daily-life mobility. These results will help to develop a more effective home-based balance telerehabilitation and virtual assessment that can be used remotely in people with balance impairments.

TRIAL REGISTRATION

This trial was prospectively registered on ClinicalTrials.gov (NCT05680597).

Differences in fall-related characteristics across cognitive disorders

Approximately 40-60% of falls in the elderly lead to injuries, resulting in disability and loss of independence. Despite the higher prevalence of falls and morbidity rates in cognitively impaired individuals, most fall risk assessments fail to account for mental status. In addition, successful fall prevention programmes in cognitively normal adults have generally failed in patients with cognitive impairment. Identifying the role of pathological aging on fall characteristics can improve the sensitivity and specificity of fall prevention approaches. This literature review provides a thorough investigation into fall prevalence and fall risk factors, the accuracy of fall risk assessments, and the efficacy of fall prevention strategies in individuals with diverse cognitive profiles. We show that fall-related characteristics differ between cognitive disorders and fall risk assessment tools as well as fall prevention strategies should critically consider each patient's cognitive status to facilitate the identification of fallers at an earlier stage and support clinical decision-making.

Lisbon Intensive Falls Trampoline Training (LIFTT) Program for people with Parkinson's for balance, gait, and falls: study protocol for a randomized controlled trial

BACKGROUND

Falling and gait difficulties in people with Parkinson's disease (PD) are associated with impaired reactive postural adjustments and impairments in attentional resources. Combined intensive balance motor and cognitive exercise can be beneficial. However, uncertainties persist regarding the true effects and safety when applying such training. Using trampoline beds may be a favorable safe environment for a highly intensive, cognitive, and balancing training approach. The primary goal of this randomized controlled trial is to assess the effects of an intensive cognitive-motor training program in a safe trampoline environment in addition to usual care on balance impairment, gait, physical capacity, fear of falling, falls frequency and severity, cognition, and clinical impairments in people with mild or moderate PD.

METHODS

Sixty participants diagnosed with idiopathic PD, in stage 2-4 Hoehn and Yahr, with a clinical history of gait deficits and a fall history (at least one fall in the last 6 months) will be recruited and randomly allocated to an intervention group receiving cognitive-motor trampoline training or a control group undergoing their usual care. The intervention will consist of 8-week individual training sessions (1-h training, 3 days per week) led by specialized physiotherapists that will provide progressive, challenging training, and guarantee safety. Assessment will be conducted prior to and immediately after the 8-week intervention and at 3 months follow-up after participating in the study. Primary outcome measures will be balance performance (assessed using the Mini-BEST Test and nonlinear analysis) and change in gait parameters (Motor and Cognitive Timed-Up-Go and nonlinear analysis). Secondary outcomes will be change in clinical improvement (Movement Disorder Society Unified Parkinson's Disease Rating Scale), falls (falls weekly registry), fear of falling (assessed using the Falls Efficacy Scale), physical capacity (6-min walk test), and cognition (Montreal Cognitive Assessment).

DISCUSSION

This study will provide new evidence on the benefits of intensive cognitive-motor balance training on a trampoline for people living with PD. Better guidance on how professionals can apply safer dual-task balance and gait training in rehabilitation is needed.

TRIAL REGISTRATION

ISRCTN Registry ISRCTN13160409 . Retrospectively registered on February 23, 2022.

An Online Dual-Task Cognitive and Motor Exercise Program for Individuals With Parkinson Disease (PD3 Move Program): Acceptability Study

BACKGROUND

Dual-task training is an emerging field used for people with Parkinson disease (PD) to improve their physical and cognitive well-being, but the patients' acceptability, safety, and adherence to such training in online settings are unknown.

OBJECTIVE

This study aims to evaluate the acceptability of a dual-task cognitive and motor online training program for people with PD as a group online community program.

METHODS

People with PD were invited to participate in an online program (PD3 Move) consisting of physical and vocal exercises in response to different cognitive challenges displayed as dynamic backgrounds on Zoom. The program ran twice per week for 16 weeks. Patient acceptability was assessed at 4 months by monitoring attendance rates and feedback from an exit questionnaire emailed to all participants assessing satisfaction, perceived benefit, safety, and willingness to continue and recommend to others.

RESULTS

The online program was delivered to 15 participants (n=9, 60%, females) with a diagnosis of PD, a mean age of 69.4 (SD 9.3) years, and Hoehn and Yahr (H&Y) stages I-IV. The attendance rate was high, with participants coming to more than 13 (81%) of the sessions. Participants were very satisfied (n=8, 53%) or satisfied (n=7, 47%) with the program. Participants reported that what they most liked were the new cognitive physical challenges. The 3 main facilitators to participating were perceiving the benefits, instructor's flexibility and engagement, and the social interaction moments with others. The 3 main difficulties were dealing with motor fluctuations (n=3, 20%), difficulties in using technology (n=2, 13%), and difficulty hearing instructions due to hearing loss (n=2, 13%). Patients had favorable perceived benefits of the program, with 14 (93%) considering it very useful for the current management of health and 1 (7%) moderately useful. No adverse events were reported, and all participants said that they were willing to continue the program and recommend it to others.

CONCLUSIONS

Our findings suggest that the online cognitive and motor program was well received, safe, and perceived to be of benefit to this group of medically stable people with PD in H&Y stages I-IV. Access to specialized care and enhancement of long-term adherence to regular exercise can be achieved with online community group programs.

Exploring the feasibility of technological visuo-cognitive training in Parkinson's: Study protocol for a pilot randomised controlled trial

Visual and cognitive dysfunction are common in Parkinson's disease and relate to balance and gait impairment, as well as increased falls risk and reduced quality of life. Vision and cognition are interrelated (termed visuo-cognition) which makes intervention complex in people with Parkinson's (PwP). Non-pharmacological interventions for visuo-cognitive deficits are possible with modern technology, such as combined mobile applications and stroboscopic glasses, but evidence for their effectiveness in PwP is lacking. We aim to investigate whether technological visuo-cognitive training (TVT) can improve visuo-cognitive function in PwP. We will use a parallel group randomised controlled trial to evaluate the feasibility and acceptability of TVT versus standard care in PwP. Forty PwP who meet our inclusion criteria will be randomly assigned to one of two visuo-cognitive training interventions. Both interventions will be carried out by a qualified physiotherapist in participants own homes (1-hour sessions, twice a week, for 4 weeks). Outcome measures will be assessed on anti-parkinsonian medication at baseline and at the end of the 4-week intervention. Feasibility of the TVT intervention will be assessed in relation to safety and acceptability of the technological intervention, compliance and adherence to the intervention and usability of equipment in participants homes. Additionally, semi structured interviews will be conducted to explore participants' experience of the technology. Exploratory efficacy outcomes will include change in visual attention measured using the Trail Making Test as well as changes in balance, gait, quality of life, fear of falling and levels of activity. This pilot study will focus on the feasibility and acceptability of TVT in PwP and provide preliminary data to support the design of a larger, multi-centre randomised controlled trial. This trial is registered at isrctn.com (ISRCTN46164906).

Compensatory movement strategies differentially affect attention allocation and gait parameters in persons with Parkinson’s disease

Persons with Parkinson’s disease (PwP) are advised to use compensatory strategies such as external cues or cognitive movement strategies to overcome gait disturbances. It is suggested that external cues involve the processing of sensory stimulation, while cognitive-movement strategies use attention allocation. This study aimed to compare over time changes in attention allocation in PwP between prolonged walking with cognitive movement strategy and external cues; to compare the effect of cognitive movement strategies and external cues on gait parameters; and evaluate whether these changes depend on cognitive function. Eleven PwP participated in a single-group pilot study. Participants walked for 10 min under each of three conditions: natural walking, using external cuing, using a cognitive movement strategy. Attention and gait variables were extracted from a single-channel electroencephalogram and accelerometers recordings, respectively. Attention allocation was assessed by the% of Brain Engagement Index (BEI) signals within an attentive engagement range. Cognitive function was assessed using a neuropsychological battery. The walk was divided into 2-min time segments, and the results from each 2-min segment were used to determine the effects of time and condition. Associations between cognitive function and BEI signals were tested. Findings show that in the cognitive movement strategy condition, there was a reduction in the % of BEI signals within the attentive engagement range after the first 2 min of walking. Despite this reduction the BEI did not consistently differ from natural and metronome walking. Spatiotemporal gait variables were better in the cognitive movement strategy condition relative to the other conditions. Global cognitive and information processing scores were significantly associated with the BEI only when the cognitive movement strategy was applied. In conclusion, the study shows that a cognitive movement strategy has positive effects on gait variables but may impose a higher attentional load. Furthermore, when walking using a cognitive movement strategy, persons with higher cognitive function showed elevated attentive engagement. The findings support the idea that cognitive and attentional resources are required for cognitive movement strategies in PwP. Additionally, this study provides support for using single-channel EEG to explore mechanistic aspects of clinical interventions.

The cortical N1 response to balance perturbation is associated with balance and cognitive function in different ways between older adults with and without Parkinson's disease

Mechanisms underlying associations between balance and cognitive impairments in older adults with and without Parkinson's disease are poorly understood. Balance disturbances evoke a cortical N1 response that is associated with both balance and cognitive abilities in unimpaired populations. We hypothesized that the N1 response reflects neural mechanisms that are shared between balance and cognitive function, and would therefore be associated with both balance and cognitive impairments in Parkinson's disease. Although N1 responses did not differ at the group level, they showed different associations with balance and cognitive function in the Parkinson's disease vs. control groups. In the control group, higher N1 amplitudes were correlated with lower cognitive set shifting ability and lower balance confidence. However, in Parkinson's disease, narrower N1 widths (i.e., shorter durations) were associated with greater parkinsonian motor symptom severity, lower balance ability and confidence, lower mobility, and lower overall cognitive function. Despite different relationships across populations, the present results suggest the N1 response reflects neural processes related to both balance and cognitive function. A better understanding of neural mechanisms linking balance and cognitive function could provide insight into associations between balance and cognitive decline in aging populations.

Reliability and validity of modified Four Square Step Test (mFSST) performance in individuals with Parkinson’s disease

BACKGROUND

Parkinson's disease (PD) is a complex disorder marked with non-motor and motor impairments, including gait abnormalities and postural instability. As a result of balance dysfunction and postural instability, falls and injuries are common composite impairments of PD. The modified Four Square Step Test (mFSST) replaces the canes utilized in the traditional Four Square Step Test (FSST) with tape to evaluate dynamic standing balance while stepping in multiple directions.

PURPOSE

Determine the reliability and validity of the mFSST in individuals with PD.

METHODS

Twenty-seven participants diagnosed with PD on medication H&Y I-III, mean age 73.07 ± 6.4, completed the FSST and mFSST. Participants performed both assessments two times using the fastest time for interrater reliability and concurrent validity. To determine the test-retest reliability, participants performed the mFSST again 20-60 min following initial assessment.

RESULTS

The interrater and test-retest reliability was excellent (r = 0.916-0.999, ICC_2,2 = 0.96-0.99). The mFSST and FSST were highly correlated for concurrent validity (r = 0.823, p < .01).

CONCLUSION

The mFSST demonstrates excellent reliability and validity while assessing dynamic standing balance in individuals with PD. The mFSST can be completed while requiring little equipment, space, and time in multiple rehabilitation settings.

Professionals' Self-Reported Difficulties towards Integrating Dual Task Training in Care for People with Parkinson's Disease

Background: Despite the growing use of dual task training (DTT) in clinical practice with people with Parkinson Disease (PD), there is still limited evidence on how to best implement it. Data regarding professionals’ difficulties when integrating such practices are critical as a first step to generate further guidance on how to apply it. The aim of this study was to identify the difficulties perceived by professionals to integrate dual task in their practice. Methods: A descriptive, observational and cross-sectional study was conducted using a web-based survey. Convenience sampling was used to recruit exercise and healthcare professionals working with people with PD through various social media channels. Data were collected and then analyzed thematically using the method of constant comparisons. The study report follows the consolidated criteria for reporting qualitative research (COREQ) checklist. Results: Of the 205 eligible responses, 68.8% were Physiotherapist. The majority of the participants reported having Parkinson-specific training (91.7%) and 59.0% applied DTT in individual one-on-one sessions. We identified ten categories of difficulties faced by professionals. Conclusions: Professionals struggle to integrate DTT into PD clinical care. Challenges were identified and the most significant refer to difficulties in managing the chronicity of the disease and lack of patient compliance with home exercises. Understanding current challenges towards dual task exercise will help to reflect upon strategies to be applied effectively and safe.

Discussion of Research Priorities for Gait Disorders in Parkinson's Disease

Gait and balance abnormalities develop commonly in Parkinson's disease and are among the motor symptoms most disabling and refractory to dopaminergic or other treatments, including deep brain stimulation. Efforts to develop effective therapies are challenged by limited understanding of these complex disorders. There is a major need for novel and appropriately targeted research to expedite progress in this area. The Scientific Issues Committee of the International Parkinson and Movement Disorder Society has charged a panel of experts in the field to consider the current knowledge gaps and determine the research routes with highest potential to generate groundbreaking data. © 2021 International Parkinson and Movement Disorder Society.

Repeated Gait Perturbation Training in Parkinson's Disease and Healthy Older Adults: A Systematic Review and Meta-Analysis

Background: Gait impairments are common in healthy older adults (HOA) and people with Parkinson's disease (PwPD), especially when adaptations to the environment are required. Traditional rehabilitation programs do not typically address these adaptive gait demands in contrast to repeated gait perturbation training (RGPT). RGPT is a novel reactive form of gait training with potential for both short and long-term consolidation in HOA and PwPD. The aim of this systematic review with meta-analysis is to determine whether RGPT is more effective than non-RGPT gait training in improving gait and balance in HOA and PwPD in the short and longer term. Methods: This review was conducted according to the PRISMA-guidelines and pre-registered in the PROSPERO database (CRD42020183273). Included studies tested the effects of any form of repeated perturbations during gait in HOA and PwPD on gait speed, step or stride length. Studies using balance scales or sway measures as outcomes were included in a secondary analysis. Effects of randomized controlled trials (RCT) on RGPT were pooled using a meta-analysis of final measures. Results: Of the 4421 studies, eight studies were deemed eligible for review, of which six could be included in the meta-analysis, totaling 209 participants (159 PwPD and 50 HOA). The studies were all of moderate quality. The meta-analysis revealed no significant effects of RGPT over non-RGPT training on gait performance (SMD = 0.16; 95% CI = -0.18, 0.49; Z = 0.92; P = 0.36). Yet, in some individual studies, favorable effects on gait speed, step length and stride length were observed immediately after the intervention as well as after a retention period. Gait variability and asymmetry, signifying more direct outcomes of gait adaptation, also indicated favorable RGPT effects in some individual studies. Conclusion: Despite some promising results, the pooled effects of RGPT on gait and balance were not significantly greater as compared to non-RGPT gait training in PwPD and HOA. However, these findings could have been driven by low statistical power. Therefore, the present review points to the imperative to conduct sufficiently powered RCT's to verify the true effects of RGPT on gait and balance in HOA and PwPD. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php? Identifier: CRD42020183273.

Impaired Inhibitory Control During Walking in Parkinson's Disease Patients: An EEG Study

BACKGROUND

The performance on a visual Go/NoGo (VGNG) task during walking has been used to evaluate the effect of gait on response inhibition in young and older adults; however, no work has yet included Parkinson's disease (PD) patients for whom such changes may be even more enhanced.

OBJECTIVE

In this study, we aimed to explore the effect of gait on automatic and cognitive inhibitory control phases in PD patients and the associated changes in neural activity and compared them with young and older adults.

METHODS

30 PD patients, 30 older adults, and 11 young adults performed a visual Go/NoGo task in a sitting position and during walking on a treadmill while their EEG activity and gait were recorded. Brain electrical activity was evaluated by the amplitude, latency, and scalp distribution of N2 and P300 event related potentials. Mix model analysis was used to examine group and condition effects on task performance and brain activity.

RESULTS

The VGNG accuracy rates in PD patients during walking were lower than in young and older adults (F = 5.619, p = 0.006). For all groups, N2 latency during walking was significantly longer than during sitting (p = 0.013). In addition, P300 latency was significantly longer in PD patients (p <  0.001) and older adults (p = 0.032) during walking compared to sitting and during 'NoGo' trials compared with 'Go' trials. Moreover, the young adults showed the smallest number of electrodes for which a significant differential activation between sit to walk was observed, while PD patients showed the largest with N2 being more strongly manifested in bilateral parietal electrodes during walking and in frontocentral electrodes while seated.

CONCLUSION

The results show that response inhibition during walking is impaired in older subjects and PD patients and that increased cognitive load during dual-task walking relates to significant change in scalp electrical activity, mainly in parietal and frontocentral channels.

Validation of Cognitive Rehabilitation as a Balance Rehabilitation Strategy in Patients with Parkinson's Disease: Study Protocol for a Randomized Controlled Trial

Background: Parkinson's disease (PD) is the second most common neurodegenerative disorder. This disease is characterized by motor symptoms, such as bradykinesia, tremor, and rigidity. Although balance impairment is characteristic of advanced stages, it can be present with less intensity since the beginning of the disease. Approximately 60% of PD patients fall once a year and 40% recurrently. On the other hand, cognitive symptoms affect up to 20% of patients with PD in early stages and can even precede the onset of motor symptoms. There are cognitive requirements for balance and can be challenged when attention is diverted or reduced, linking a worse balance and a higher probability of falls with a slower cognitive processing speed and attentional problems. Cognitive rehabilitation of attention and processing speed can lead to an improvement in postural stability in patients with Parkinson's. Methods: We present a parallel and controlled randomized clinical trial (RCT) to assess the impact on balance of a protocol based on cognitive rehabilitation focused on sustained attention through the NeuronUP platform (Neuronup SI, La Rioja, Spain) in patients with PD. For 4 weeks, patients in the experimental group will receive cognitive therapy three days a week while the control group will not receive any therapy. The protocol has been registered at trials.gov NCT04730466. Conclusions: Cognitive therapy efficacy on balance improvement may open the possibility of new rehabilitation strategies for prevention of falls in PD, reducing morbidity, and saving costs to the health care system.

Evidence for Early and Regular Physical Therapy and Exercise in Parkinson's Disease

Advances in medical management of Parkinson's disease (PD) have resulted in living longer with disability. Although disability worsens over the course of the disease, there are signs of disability even in the early stages. Several studies reveal an early decline in gait and balance and a high prevalence of nonmotor signs in the prodromal period that contribute to early disability. There is a growing body of evidence revealing the benefits of physical therapy and exercise to mitigate motor and nonmotor signs while improving physical function and reducing disability. The presence of early disability coupled with the benefits of exercise suggests that physical therapy should be initiated earlier in the disease. In this review, we present the evidence revealing early disability in PD and the effectiveness of physical therapy and exercise, followed by a discussion of a secondary prevention model of rehabilitation to reduce early disability and optimize long-term outcomes.

Attention and sensory integration for postural control in young adults with autism spectrum disorders

Postural control impairments have been reported in adults with autism spectrum disorders (ASD). Balance relies on the integration of multisensory cues, a process that requires attention. The purpose of this study was to determine if the influence of attention demands on sensory integration abilities relevant for balance partially contributes to postural control impairments in ASD. Young adults with ASD (N = 24) and neurotypical participants (N = 24) were exposed to sensory perturbations during standing. An established dual-task paradigm was used, requiring participants to maintain balance in these sensory challenging environments and to perform auditory information processing tasks (simple reaction time task and choice reaction time task). Balance was assessed using sway magnitude and sway speed, and attention demands were evaluated based on the response time in the auditory tasks. While young adults with ASD were able to maintain balance in destabilizing sensory conditions, they were more challenged (greater sway speed) than their neurotypical counterparts. Additionally, when exposed for an extended amount of time (3 min) to the most challenging sensory condition included in this study, adults with ASD exhibited a reduced ability to adapt their postural control strategies (sway speed was minimally reduced), demonstrating a postural inflexibility pattern in ASD compared to neurotypical counterparts. Finally, the impact of performing an auditory information processing task on balance and the dual-task cost on information processing (response time) was similar in both groups. ASD may disrupt temporal adaptive postural control processes associated with sensory reweighting that occurs in neurotypicals.

Timed Up and Go Test With a Cognitive Task: Correlations With Neuropsychological Measures in People With Parkinson's Disease

Background

The Timed Up and Go (TUG) test is a simple and widely used clinical test for the assessment of lower extremity function, balance, mobility, and fall risk in various populations. The TUG has been found as a valid and reliable measure in people with Parkinson’s disease (PD). Besides, the addition of a cognitive task to the TUG (TUG-cognitive) enhances predictive validity related to fall risk in people with PD. However, further investigation is needed about the correlations of the TUG-cognitive test with neuropsychological measures in people with PD.

Methods

Thirty-three people with PD [modified Hoehn and Yahr scale, median (min-max)=2.5 (1.0-3.0)] participated in this cross-sectional study. The TUG was administered in the traditional way and with a cognitive task (counting backward by three from any number between 20 and 100). Neuropsychological measures included the Montreal Cognitive Assessment (MoCA), Trail Making Test (TMT), and the Simple Reaction Time (SRT) test for stepping. The self-reported number of falls in the last six months was also recorded.

Results

The TUG-cognitive [13.1 (SD=8.5) seconds] was significantly longer than the TUG-traditional [12.2 (SD=8.1) seconds] (p<0.01). The TUG-cognitive significantly correlated with the MoCA [(rho=-0.712), TMT part A (TMT-A; rho=0.722), TMT part B (TMT-B; rho=0.694), SRT (rho=0.794), and number of falls (rho=0.960)] (p<0.01). The TUG-traditional also significantly correlated with the MoCA (rho=-0.682), TMT-A (rho=0.684), TMT-B (rho=0.746), SRT (rho=0.755), and number of falls (rho=0.702) (p<0.01).

Conclusion

Both the TUG-cognitive and TUG-traditional strongly correlated with neuropsychological measures; while the correlations were slightly stronger for the TUG-cognitive, the difference was not significant. The TUG-cognitive can be used in the clinical practice as a simple and more informative alternative to the TUG-traditional in people with PD.

Relationship between malnutrition and different fall risk assessment tools in a geriatric in-patient unit

BACKGROUND

Despite decades of research evaluating different predictive strategies to identify persons at risk for falls, nutritional issues have received little attention. Malnutrition leads to weight loss associated with muscle weakness and consequently increases the risk of falls.

AIMS

The current study assessed the association between nutritional state and fall risk scores in a geriatric in-patient unit in Ain Shams University Hospital, Cairo, Egypt.

METHODS

A cross-sectional study was conducted to assess the nutritional state of 190 older inpatients using a short form of the Mini-Nutritional Assessment (MNA-SF), and the risk of falls was assessed using the Morse Fall Scale (MFS), Johns Hopkins fall risk assessment tool (JH-FRAT), Schmid Fall Risk Assessment Tool (Schmid-FRAT), Hendrich II Fall Risk Model (HII-FRM) and Functional Assessment Instrument (FAI). The generalised linear models (GLM) and odds ratio (OR) were calculated to test the nutritional status as a risk factor for falls.

RESULTS

Malnutrition was significantly associated with high fall risk as assessed by MFS and HII-FRM (OR = 2.833, 95% CI 1.358-5.913, P = 0.006; OR = 3.477, 95% CI 1.822-6.636, P < 0.001), with the highest OR for JH-FRAT (OR = 5.455, 95% CI 1.548-19.214, P = 0.008). After adjusting for age, the adjusted Charlson Comorbidity Index (ACCI), number of fall risk-increasing drugs (FRIDs), risk of malnutrition or malnourished were significantly associated with high fall risk as assessed by MFS (OR = 2.761, 95% CI 1.306-5.836, P = 0.008), JH-FRAT (OR = 4.938, 95% CI 1.368-17.828, P = 0.015), and HII-FRM (OR = 3.486, 95% CI 1.783-6.815, P < 0.001).

CONCLUSIONS

This study demonstrated a significant association between malnutrition and fall risk assessment scores, especially JH-FRAT, in hospitalised older patients.

Association Between Motor Subtype and Visuospatial and Executive Function in Mild-Moderate Parkinson Disease

OBJECTIVE

To compare participants with Parkinson disease (PD) motor subtypes, postural instability and gait difficulty (PIGD) (n=46) and tremor dominant (TD) (n=28), in cognitive and motor-cognitive assessments with the purpose of identifying associations between subtype and visuospatial, whole-body spatial, inhibition and/or switching, and planning and/or organizational aspects of cognitive and motor-cognitive function.

DESIGN

Retrospective cohort study. Fisher exact test was used for categorical variables, while 2-sample independent t tests were used to analyze continuous variables.

SETTING

Assessments took place at Emory University.

PARTICIPANTS

Participants (N=72) were 40 years and older, had a clinical diagnosis of PD, exhibited 3 of the 4 cardinal signs of PD, had shown benefit from antiparkinsonian medications, and were in Hoehn and Yahr stages I-IV. Participants could walk 3 m or more with or without assistance.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Balance and mobility tests included Fullerton Advanced Balance Scale and the time needed to turn 360 degrees. Cognitive assessments included Montreal Cognitive Assessment, Brooks Spatial Memory Task, Color-Word Interference Test, Tower of London, Trail Making Test, Corsi Blocks, Serial 3s Subtraction, and Body Position Spatial Task. Motor-cognitive function measures included Four Square Step Test and Timed Up and Go.

RESULTS

Participants with PIGD performed lower than those with TD symptoms on mental status (P=.005), spatial memory (P=.027), executive function (P=.0001-.034), and visuospatial ability (P=.048).

CONCLUSIONS

Findings suggest that PIGD subtype is linked to greater deficits in spatial cognition, attentional flexibility and organizational planning, and whole-body spatial memory domains. These findings support the need for more personalized approaches to clinically managing PD.

Implementation of a Community-Based Exercise Program for Parkinson Patients: Using Boxing as an Example

BACKGROUND

Persons with Parkinson's disease (PD) benefit from continuous exercise through participation in community-based exercise programs. However, community programs often lack PD-specific knowledge needed to provide safe and adequately dosed exercise.

OBJECTIVE

To evaluate the acceptability and safety of a PD-specific boxing program in the community.

METHODS

We developed specific educational resources to facilitate the boxing instructors. We also organized an educational and practical workshop for patients (n = 26) and instructors (n = 10), and assessed: (a) participants' satisfaction; (b) instructors' appreciation of the educational resources; and (c) numbers of patients interested in participating in the boxing program. After 18 months, patients and instructors completed a questionnaire evaluating: (a) participants' satisfaction; (b) adverse events; (c) facilitators and barriers; and (d) proportion of participants at follow-up.

RESULTS

Twenty-six persons with PD (62% men) and 10 boxing instructors participated in the workshop. 81% of patients and 80% of instructors were very satisfied. Instructors found the educational materials "very helpful" (60%) or "helpful" (40%). Patients expressed a clear interest (54%) or possible interest (46%) in the program. We initiated classes with 10 participants. At 18-months follow-up, the program consisted of four boxing sessions/week, led by three instructors, with 40 participants. Seventeen patients responded to the questionnaire at follow-up. Participants were "very satisfied" (53%), "satisfied" (35%) and neither satisfied nor unsatisfied (12%) with the program. Adverse effects were mild (e.g., muscle aches). Transportation and physical disability were the main barriers for participation.

CONCLUSIONS

The boxing program was well-received, with increasing numbers of participants at 18 months. The educational resources can support boxing instructors participating in current and future boxing classes being delivered in the community.

Enhanced Obstacle Contrast to Promote Visual Scanning in Fallers with Parkinson's Disease: Role of Executive Function

The ability to perceive differences in environmental contrast is critical for navigating complex environments safely. People with Parkinson's disease (PD) report a multitude of visual and cognitive deficits which may impede safe obstacle negotiation and increase fall risk. Enhancing obstacle contrast may influence the content of visual information acquired within complex environments and thus target environmental fall risk factors. 17 PD with a history of falls and 18 controls walked over an obstacle covered in a high and low contrast material in separate trials whilst eye movements were recorded. Measures of visual function and cognition were obtained. Gaze location was extracted during the approach phase. PD spent longer looking at the obstacle compared to controls regardless of contrast (p < .05), however group differences were largest for the low contrast obstacle. When accounting for group differences in approach time, PD spent longer looking at the low contrast obstacle and less time looking at the ground beyond the low contrast obstacle compared to controls (p < .05). The response to obstacle contrast in PD (high-low) was significantly associated with executive function. Better executive function was associated with spending longer looking at the low contrast obstacle and at the ground beyond the high contrast obstacle. Enhancing the contrast of ground-based trip hazards may improve visual processing of environmental cues in PD, particularly for individuals with better executive function. Manipulating contrast to attract visual attention is already in use in the public domain, however its utility for reducing fall risk in PD is yet to be formally tested in habitual settings.

Parkinson Disease and Orthostatic Hypotension in the Elderly: Recognition and Management of Risk Factors for Falls

Parkinson disease (PD) is often associated with postural instability and gait dysfunction that can increase the risk for falls and associated consequences, including injuries, increased burden on healthcare resources, and reduced quality of life. Patients with PD have nearly twice the risk for falls and associated bone fractures compared with their general population counterparts of similar age. Although the cause of falls in patients with PD may be multifactorial, an often under-recognized factor is neurogenic orthostatic hypotension (nOH). nOH is a sustained decrease in blood pressure upon standing whose symptomology can include dizziness/lightheadedness, weakness, fatigue, and syncope. nOH is due to dysfunction of the autonomic nervous system compensatory response to standing and is a consequence of the neurodegenerative processes of PD. The symptoms associated with orthostatic hypotension (OH)/nOH can increase the risk of falls, and healthcare professionals may not be aware of the real-world clinical effect of nOH, the need for routine screening, or the value of early diagnosis of nOH when treating elderly patients with PD. nOH is easily missed and, importantly, healthcare providers may not realize that there are effective treatments for nOH symptoms that could help lessen the fall risk resulting from the condition. This review discusses the burden of, and key risk factors for, falls among patients with PD, with a focus on practical approaches for the recognition, assessment, and successful management of OH/nOH. In addition, insights are provided as to how fall patterns can suggest fall etiology, thereby influencing the choice of intervention.

Examining the Feasibility of a Mindfulness Intervention for the Prevention of Falls: A Pilot Study

This pilot study was designed to assess the feasibility of implementing a mindfulness intervention in the prevention of falls. We employed a quasi-experimental design consisting of 22 participants from two retirement homes in Ontario partaking in the regional falls prevention class. Participants were assigned to either an eight-week intervention, comprising mindfulness exercises incorporated into the standard falls prevention class, or to the standard falls prevention class. Participants were assessed using the Tinetti Balance and Gait Scale and the Timed Up and Go (TUG) test. The mindfulness intervention showed no significant effect on TUG or balance scores; however, there was a significant effect on assessments of gait. Given the ease of implementation of mindfulness-based interventions, further research may be warranted in mindfulness as a potential modality for falls prevention.

Altered reward-related neural responses in non-manifesting carriers of the Parkinson disease related LRRK2 mutation

Disturbances in reward processing occur in Parkinson's disease (PD) however it is unclear whether these are solely drug-related. We applied an event-related fMRI gambling task to a group of non-manifesting carriers (NMC) of the G2019S mutation in the LRRK2 gene, in order to assess the reward network in an "at risk" population for future development of PD. Sixty-eight non-manifesting participants, 32 of which were non-manifesting non-carriers (NMNC), performed a gambling task which included defined intervals of anticipation and response to both reward and punishment in an fMRI setup. Behavior and cerebral activations were measured using both hypothesis driven and whole brain analysis. NMC demonstrated higher trait anxiety scores (p = 0.04) compared to NMNC. Lower activations were detected among NMC during risky anticipation in the left nucleus accumbens (NAcc) (p = 0.05) and during response to punishment in the right insula (p = 0.02), with higher activations among NMC during safe anticipation in the right insula (p = 0.02). Psycho-Physiological Interaction (PPI) analysis from the NAcc and insula revealed differential connectivity patterns. Whole brain analysis demonstrated divergent between-group activations in distributed cortical regions, bilateral caudate, left midbrain, when participants were required to press the response button upon making their next chosen move. Abnormal neural activity in both the reward and motor networks were detected in NMC indicating involvement of the ventral striatum regardless of medication use in "at risk" individuals for future development of PD.

High-density EEG mobile brain/body imaging data recorded during a challenging auditory gait pacing task

In this report we present a mobile brain/body imaging (MoBI) dataset that allows study of source-resolved cortical dynamics supporting coordinated gait movements in a rhythmic auditory cueing paradigm. Use of an auditory pacing stimulus stream has been recommended to identify deficits and treat gait impairments in neurologic populations. Here, the rhythmic cueing paradigm required healthy young participants to walk on a treadmill (constant speed) while attempting to maintain step synchrony with an auditory pacing stream and to adapt their step length and rate to unanticipated shifts in tempo of the pacing stimuli (e.g., sudden shifts to a faster or slower tempo). High-density electroencephalography (EEG, 108 channels), surface electromyography (EMG, bilateral tibialis anterior), pressure sensors on the heel (to register timing of heel strikes), and goniometers (knee, hip, and ankle joint angles) were concurrently recorded in 20 participants. The data is provided in the Brain Imaging Data Structure (BIDS) format to promote data sharing and reuse, and allow the inclusion of the data into fully automated data analysis workflows.

Trial-by-trial source-resolved EEG responses to gait task challenges predict subsequent step adaptation

A growing body of evidence indicates a pivotal role of cognition and in particular executive function in gait control and fall prevention. In a recent gait study using electroencephalographic (EEG) imaging, we provided direct proof for cortical top-down inhibitory control in step adaptation. A crucial part of motor inhibition is recognizing stimuli that signal the need to inhibit or adjust motor actions such as steps during walking. One of the EEG signatures of performance monitoring in response to events signaling the need to adjust motor responses, are error-related potential (error-ERP) features. To examine whether error-ERP features may index executive control during gait adaptation, we analyzed high-density (108-channel) EEG data from an auditory gait pacing study. Participants (N = 18) walking on a steadily moving treadmill were asked to step in time to an auditory cue tone sequence, and then to quickly adapt their step length and rate, to regain step-cue synchrony following occasional unexpected shifts in the pacing cue train to a faster or slower cue tempo. Decomposition of the continuous EEG data by independent component analysis revealed a negative deflection in the source-resolved event-related potential (ERP) time locked to 'late' cue tones marking a shift to a slower cue tempo. This vertex-negative ERP feature, localized primarily to posterior medial frontal cortex (pMFC) and peaking 250 ms after the onset of the tempo-shift cue, we here refer to as the step-cue delay negativity (SDN). SDN source, timing, and polarity resemble other error-related ERP features, e.g., the Error-Related Negativity (ERN) and Feedback-Related Negativity (FRN) in (seated) button press response tasks. In single trials, SDN amplitude varied with the magnitude of the cue latency deviation (the time interval between the expected and actual cue onsets). Regression analysis also identified linear coupling between SDN amplitude and the subsequent speed of gait tempo adaptation (as measured by the increase in length of the ensuing adaptation step). The SDN in this paradigm thus seems both to index the perceived need for and the subsequent magnitude of the immediate gait adjustment, consistent with performance-monitoring models. Future research might investigate relationships of these control processes to the impairment of gait adjustment in motor disorders and cognitive decline, for example to develop a biomarker for fall risk prediction in early-stage Parkinson's.

Ramadan Fasting Effects on Postural Control in the Elderly: A Comparison Between Fallers and Non-fallers

Our purpose was to compare the effects of Ramadan fasting on postural control in elderly fallers and non-fallers. The protocol involved twenty-four healthy old volunteer males divided into two groups: fallers (mean age = 75.43 ± 5.26 years, weight = 67.25 ± 5.30 kg and height = 1.65 ± 0.02 m) and non-fallers (mean age = 72.3 ± 6.42 years, weight = 65.5 ± 6.15 kg and height = 1.64 ± 0.03 m). Participants performed a simple reaction time test (SRT) and a postural control protocol on four different occasions: one week before Ramadan (BR), during the second (SWR) and the fourth week (FWR) of Ramadan and three weeks after Ramadan (AR). Center of pressure (CoP) parameters [the CoP medial-lateral length (CoP_X), and the CoP antero-posterior length (CoP_Y)] were assessed using a force platform under two surface conditions: Firm surface and Foam surface. The results showed that Ramadan fasting influences similarly fallers and non-fallers. In fact, for both groups, the CoP_X and the CoP_Y values increased significantly during the SWR and the FWR compared to BR. These CoP parameters decreased significantly in the Firm surface conditions in the FWR. Moreover, the CoP parameters were significantly higher during the FWR and AR in comparison with BR in the Foam surface conditions. However, the amplitude of increase of the CoP_[X] % and the CoP_[Y] % (ΔCoP_[X] % and ΔCoP_[Y] %) between BR and the SWR was significantly higher in the fallers than non-fallers. The SRT of elderly fallers and non-fallers was significantly higher in the SWR and in the FWR compared to BR. In conclusion, Ramadan fasting alters similarly postural control of elderly fallers and non-fallers, but the amplitude (ΔCoP_[X] % and ΔCoP_[Y] %) of this alteration seems to be more pronounced in fallers than non-fallers. A probable beginning of adaptation occurs at the FWR. However, three weeks seems to be insufficient to recover postural control alterations due to Ramadan fasting in difficult sensory conditions in elderly fallers and non-fallers.

The Body Position Spatial Task, a Test of Whole-Body Spatial Cognition: Comparison Between Adults With and Without Parkinson Disease

BACKGROUND

The Body Position Spatial Task (BPST) is a novel measure of whole-body spatial cognition involving multidirectional steps and turns. Individuals with Parkinson disease (PD) are affected by motor and cognitive impairments, particularly in spatial function, which is important for mental imagery and navigation. Performance on the BPST may inform understanding of motor-cognitive and spatial cognitive function of individuals with PD.

OBJECTIVES

We conducted this study to determine feasibility and validity of the BPST with standard, validated, and reliable measures of spatial cognition and motor-cognitive integration and to compare BPST performance in adults with and without PD.

METHODS

A total of 91 individuals with mild-moderate PD and 112 neurotypical (NT) adults of similar age were recruited for the study to complete the BPST and other measures of mobility and cognition. Correlations were used to determine construct and concurrent validity of BPST with valid measures of spatial cognition and motor-cognitive integration. Performance was compared between PD and NT adults using independent t-tests.

RESULTS

BPST was feasible to administer. Analyses show evidence of construct validity for spatial cognition and for motor-cognitive integration. Concurrent validity was demonstrated with other tests of mobility and cognition. Relationships were stronger and more significant for individuals with PD than for NT individuals. BPST performance was not significantly different between groups.

CONCLUSION

Tests that integrate cognitive challenge in mobility contexts are necessary to assess the health of spatial cognitive and motor-cognitive integration. The BPST is a feasible and valid test of whole-body spatial cognition and motor-cognitive integration in individuals with PD.

The effect of working memory intervention on the gait patterns of the elderly

INTRODUCTION

The purpose of this study was to evaluate the role of working memory (WM) training on walking patterns in elderly people.

METHODS

20 elderly adults were selected and assigned randomly to two groups: WM training group and control group. WM training group received 6 weeks of computerized training on various spatial and verbal WM tasks. The spatial-temporal parameters, the ground reaction force and the timing activity of muscles in pre-posttest and in a follow-up were taken.

RESULT

The results indicated that a significant change in gait speed, double support time and stride time (p < 0.05). Alternations in ground reaction force (GRF) components were found significant. Timing of muscle activity also showed non-significant change after WM intervention.

CONCLUSION

Based on the results of this study, it can be concluded that WM intervention can be applied to improve gait parameters. The improvements in vertical ground reaction force after training may result in an increase upright stability and a decreased in rate falls.

Cognitive profile of non-demented Parkinson's disease: Meta-analysis of domain and sex-specific deficits

INTRODUCTION

Better awareness of the cognitive domains affected in non-demented Parkinson's Disease (PD) should improve understanding of cognitive disease mechanisms. A complete understanding of the cognitive areas impaired in non-demented PD is hindered because most studies use small clinical samples without comparison to healthy controls. This meta-analysis examined cumulative evidence across studies to determine if there were impairments in non-demented PD in the three cognitive domains thought to be most widely affected in PD: frontal executive, visuospatial, and verbal memory. Because there are well-documented sex differences in PD, a second objective was to explore sex differences in these findings.

METHODS

MEDLINE, EMBASE and PsycINFO databases were searched (1988-March 2017). Random effects models were used to compute and compare effect sizes of differences between PD patients and controls within cognitive domains. Sex differences in effect sizes were also examined in these comparisons. Moderating factors including age, disease duration, motor symptom severity, levodopa dosage, and depression were examined through meta-regression.

RESULTS

PD patients showed deficits of moderate effect sizes in all three cognitive domains relative to controls. Significant sex differences were observed only for frontal executive abilities, with male PD patients showing greater deficits than female PD patients relative to controls. No moderators of effect sizes were identified in the domain specific overall or sex-segregated meta-analyses.

CONCLUSIONS

Results indicate that non-demented PD patients have deficits of moderate magnitude in frontal executive, verbal memory, and visuospatial abilities. Our findings of greater frontal executive deficits in males warrant further confirmation.

Noninvasive brain stimulation over dorsolateral prefrontal cortex for pain perception and executive function in aging

OBJECTIVES

Based on the evidence that the dorsolateral prefrontal cortex (DLPFC) is the main region affected by the aging process, and that tDCS modulates cortical excitability, the aim of the study is to prove the feasibility of tDCS for pain perception and executive function of community-dwelling elderly individuals.

METHODS

We performed a double-blind, single-arm trial, including a sham period. 5 consecutive anodal tDCS was applied over DLPFC of twenty-four elderly for 20 min during each intervention periods (in order of Sham-1 mA-2 mA). First, we classified chronic non-inflammatory pain sites into three domain (Neck and upper extremity, low back, lower extremity). Then, we used visual analogue scale, pain self-efficacy scale, Tampa scale for kinesiophobia, and Global perceived Effect scale to observe the change in pain perception, as well as Trailing Making Test and Timed Up and Go (dual) to observe the change in executive function. The changes in maximal grip strength and 12-item Short Form survey were measured secondarily.

RESULTS

In the results, we observed significant improvement in pain perception and quality of life, while executive function and grip strength did not change significantly.

CONCLUSION

Our findings demonstrated the feasibility of tDCS for aging-related pain perception and suggest that further randomized controlled trials with longer duration are necessary to examine the effects on executive function.

Inter-trial variability in brain activity as an indicator of synergistic effects of HIV-1 and drug abuse

BACKGROUND

The objective of this investigation was to detect evidence of the synergism in the effects of HIV-1 and drug abuse on brain function that has been hypothesized but rarely shown. The investigation incorporated several noteworthy improvements in the approach. It used urine toxicology tests to exclude participants complicated by recent methadone use and illicit drug use. Also, it defined drug abuse on a scale that considered symptom severity. Most importantly, it examined inter-trial variability in brain activity as a potentially more sensitive indicator of group differences and functional impairment than the across-trial average.

METHODS

173 participants were assigned to groups defined by their HIV-1 serostatus and Drug Abuse Screening Test score (DAST < vs. > = 6). They completed a simple letter discrimination task including rare target and rare nontarget stimuli. Event-related electroencephalographic responses and key press responses were measured on each trial. During a separate assessment, posturographic measures were recorded.

RESULTS

The inter-trial standard deviation of P300-like activity was superior to the mean amplitude of this activity in differentiating the groups. Unlike the mean, it revealed synergistic statistical effects of HIV and drug abuse. It also correlated significantly with static ataxia.

CONCLUSIONS

Inter-trial variability in P300-like activity is a useful marker for detecting subtle and episodic disruptions in brain function. It demonstrates greater sensitivity than the mean amplitude for detecting differences across groups. Also, as a putative indicator of a disruption in the attentional monitoring of behavior, it predicts subtle impairments in gross motor function.

Neurocognitive evaluation of brain metastases patients treated with post-resection stereotactic radiosurgery: a prospective single arm clinical trial

PURPOSE

Post-operative radiation therapy for brain metastases (BM) has become standard treatment. Concerns regarding the deleterious cognitive effects of Whole Brain Radiation Therapy spurred a trend to use focal therapies such as stereotactic radiosurgery (SRS). The purpose of this study was to prospectively evaluate the neuropsychological effects following post-resection SRS treatment since limited data exist in this context.

METHODS

We conducted a prospective single arm cohort study of patients with 1-2 BM, who underwent resection of a single BM between May 2015 to December 2016. Patients were evaluated for cognitive functions (NeuroTrax computerized neuropsychological battery; Modiin, Israel) and quality of life (QOL; QLQ-30, QLQ-BN20) before and 3 months following post-resection SRS.

RESULTS

Twelve out of 14 patients completed pre- and post-SRS neurocognitive assessments. Overall, we did not detect significant neurocognitive or QOL changes 3 months following SRS. In a subgroup analysis among patients younger than 60 years, median global cognitive score increased from a pre-treatment score of 88 (72-102) to 95 (79-108), 3 months following SRS treatment, p = 0.042; Wilcoxon paired non-parametric test. Immediate verbal memory and executive functions scores increased from 86 (72-98) to 98 (92-112) and 86 (60-101) to 100 (80-126), respectively, p = 0.043. No significant cognitive changes were discovered among patients at the age of 60 or older.

CONCLUSIONS

Post-resection radiosurgery has a safe neuro-cognitive profile and is associated with preservation of nearly all quality of life parameters. Patients younger than 60 years benefit most and may even regain some cognitive functions within a few months after treatment.

Gait Patterns in Parkinson's Disease with or without Cognitive Impairment

Background and Purpose

Cognitive and gait disturbance are common symptoms in Parkinson's disease (PD). Although the relationship between cognitive impairment and gait dysfunction in PD has been suggested, specific gait patterns according to cognition are not fully demonstrated yet. Therefore, the aim of this study was to investigate gait patterns in PD patients with or without cognitive impairment.

Methods

We studied 86 patients at an average of 4.8 years after diagnosis of PD. Cognitive impairment was defined as scoring 1.5 standard deviation below age- and education-specific means on the Korean version of the Mini-Mental State Examination (K-MMSE). Three-dimensional gait analysis was conducted for all patients and quantified gait parameters of temporal-spatial data were used. Relationships among cognition, demographic characteristics, clinical features, and gait pattern were evaluated.

Results

Cognitive impairment was observed in 41 (47.7%) patients. Compared to patients without cognitive impairment, patients with cognitive impairment displayed reduced gait speed, step length, and stride length. Among K-MMSE subcategories, “registration,” “attention/calculation,” and “visuospatial function” were significantly associated with speed, step length, and stride length. However, age, disease duration, Hoehn-Yahr (HY) stage, or Unified Parkinson's Disease Rating Scale (UPDRS) motor score was not significantly related to any gait analysis parameter.

Conclusions

Our present study shows that cognitive impairment is associated with slow and short-stepped gait regardless of HY stage or UPDRS motor score, suggesting that cognitive impairment may serve as a surrogate marker of gait disturbance or fall in PD patients.

What predicts falls in Parkinson disease?: Observations from the Parkinson's Foundation registry

BACKGROUND

We undertook this study to identify patients with Parkinson disease (PD) with no or rare falls who may progress to frequent falling by their next annual follow-up visit.

METHODS

We analyzed data in the National Parkinson Foundation Quality Improvement Initiative database to identify factors predicting which patients with PD with no or rare falls at the baseline visit will report at least monthly falls at the annual follow-up visit. Multivariable models were constructed using logistic regression. Variables were introduced in 4 blocks: in the 1st block, variables present at or before the baseline visit were entered; in the 2nd, baseline visit assessments; in the 3rd, interventions implemented during baseline visit; and, in the 4th block, changes in comorbidities, living situation, and treatment between visits.

RESULTS

Of 3,795 eligible participants, 3,276 (86.3%) reported no or rare falls at baseline visit, and of them, 382 (11.7%) reported at least monthly falls at follow-up visit. Predictors included female sex, <90% diagnostic certainty, motor fluctuations, levodopa treatment, antidepressant treatment, prior deep brain stimulation (DBS), worse quality of life, Hoehn & Yahr stage 2 or 3, worse semantic fluency, and, between visits, addition of amantadine, referral to occupational therapy, social services, or DBS, new diagnoses of cancer or osteoarthritis, and increased emergency visits.

CONCLUSIONS

This large-scale analysis identified several predictors of progression to falling in PD. Such identifiers may help target patient subgroups for falls prevention intervention. Some factors are modifiable, offering opportunities for developing such interventions.

Fall incidence and associated risk factors among people with a lower limb amputation during various stages of recovery - a systematic review

Purpose: The objective of this study was to estimate fall incidence and describe associated risk factors among people with a lower limb amputation (LLA) during various stages of recovery: the surgical ward, in-patient rehabilitation and return to community life. Materials and methods: A systematic search of relevant English language articles was performed using PubMed and EMBASE. Out of 310 initial "hits," six retrospective cohort studies, one prospective cohort study and eleven cross-sectional studies from which fall incidence and risk factors could be extracted, were selected for critical review. Fall incidence and associated risk factors were extracted and analyzed in the context of various clinical stages of recovery after amputation. The studies were evaluated for quality using the "Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies." Results: Results showed that during all stages of recovery, people with a LLA are at increased risk of falling compared with able-bodied individuals, as well as other clinical populations. Each stage of recovery is associated with different fall risk factors. The current review is limited mainly by the paucity of studies on the topic. Conclusions: Specialised care focusing on the most relevant risk factors for each stage of recovery may enhance fall prevention during post-fall recovery. Implications for rehabilitation •  People with a lower limb amputation are at a high risk of falling in all stages of their clinical course.      •  Health professionals should be aware that people with a lower limb amputation in the first 4 years ofamputation or with four or more health-related problems are at an increased risk.      •  Health professionals should also be aware that increased gait variability, excess confidence in balance andwalking abilities and less cautious stair walking, impose an elevated risk of falling and should focus theirefforts in reducing these factors.

Stepping reaction time and gait adaptability are significantly impaired in people with Parkinson's disease: Implications for fall risk

BACKGROUND

Decline in the ability to take effective steps and to adapt gait, particularly under challenging conditions, may be important reasons why people with Parkinson's disease (PD) have an increased risk of falling. This study aimed to determine the extent of stepping and gait adaptability impairments in PD individuals as well as their associations with PD symptoms, cognitive function and previous falls.

METHODS

Thirty-three older people with PD and 33 controls were assessed in choice stepping reaction time, Stroop stepping and gait adaptability tests; measurements identified as fall risk factors in older adults.

RESULTS

People with PD had similar mean choice stepping reaction times to healthy controls, but had significantly greater intra-individual variability. In the Stroop stepping test, the PD participants were more likely to make an error (48 vs 18%), took 715 ms longer to react (2312 vs 1517 ms) and had significantly greater response variability (536 vs 329 ms) than the healthy controls. People with PD also had more difficulties adapting their gait in response to targets (poorer stepping accuracy) and obstacles (increased number of steps) appearing at short notice on a walkway. Within the PD group, higher disease severity, reduced cognition and previous falls were associated with poorer stepping and gait adaptability performances.

CONCLUSIONS

People with PD have reduced ability to adapt gait to unexpected targets and obstacles and exhibit poorer stepping responses, particularly in a test condition involving conflict resolution. Such impaired stepping responses in Parkinson's disease are associated with disease severity, cognitive impairment and falls.

Gait and Cognition in Parkinson's Disease: Cognitive Impairment Is Inadequately Reflected by Gait Performance during Dual Task

Introduction

Cognitive and gait deficits are common symptoms in Parkinson’s disease (PD). Motor-cognitive dual tasks (DTs) are used to explore the interplay between gait and cognition. However, it is unclear if DT gait performance is indicative for cognitive impairment. Therefore, the aim of this study was to investigate if cognitive deficits are reflected by DT costs of spatiotemporal gait parameters.

Methods

Cognitive function, single task (ST) and DT gait performance were investigated in 67 PD patients. Cognition was assessed by the Montreal Cognitive Assessment (MoCA) followed by a standardized, sensor-based gait test and the identical gait test while subtracting serial 3’s. Cognitive impairment was defined by a MoCA score <26. DT costs in gait parameters [(DT − ST)/ST × 100] were calculated as a measure of DT effect on gait. Correlation analysis was used to evaluate the association between MoCA performance and gait parameters. In a linear regression model, DT gait costs and clinical confounders (age, gender, disease duration, motor impairment, medication, and depression) were correlated to cognitive performance. In a subgroup analysis, we compared matched groups of cognitively impaired and unimpaired PD patients regarding differences in ST, DT, and DT gait costs.

Results

Correlation analysis revealed weak correlations between MoCA score and DT costs of gait parameters (r/r_Sp ≤ 0.3). DT costs of stride length, swing time variability, and maximum toe clearance (|r/r_Sp| > 0.2) were included in a regression analysis. The parameters only explain 8% of the cognitive variance. In combination with clinical confounders, regression analysis showed that these gait parameters explained 30% of MoCA performance. Group comparison revealed strong DT effects within both groups (large effect sizes), but significant between-group effects in DT gait costs were not observed.

Conclusion

These findings suggest that DT gait performance is not indicative for cognitive impairment in PD. DT effects on gait parameters were substantial in cognitively impaired and unimpaired patients, thereby potentially overlaying the effect of cognitive impairment on DT gait costs. Limits of the MoCA in detecting motor-function specific cognitive performance or variable individual response to the DT as influencing factors cannot be excluded. Therefore, DT gait parameters as marker for cognitive performance should be carefully interpreted in the clinical context.

Gaze and motor behavior of people with PD during obstacle circumvention

The aim of this study was to analyze the motor and visual strategies used when walking around (circumvention) an obstacle in patients with Parkinson's disease (PD), in addition to the effects of dopaminergic medication on these strategies. To answer the study question, people with PD (15) and neurologically healthy individuals (15 - CG) performed the task of obstacle circumvention during walking (5 trials of unobstructed walking and obstacle circumvention). The following parameters were analyzed: body clearance (longer mediolateral distance during obstacle circumvention of the center of mass -CoM- to the obstacle), horizontal distance (distance of the CoM at the beginning of obstacle circumvention to the obstacle), circumvention strategy ("lead-out" or "lead-in" strategy), spatial-temporal of each step, and number of fixations, the mean duration of the fixations and time of fixations according to areas of interest. In addition, the variability of each parameter was calculated. The results indicated that people with PD and the CG presented similar obstacle circumvention strategies (no differences between groups for body clearance, horizontal distance to obstacle, or obstacle circumvention strategy), but the groups used different adjustments to perform these strategies (people with PD performed adjustments during both the approach and circumvention steps and presented greater visual dependence on the obstacle; the CG adjusted only the final step before obstacle circumvention). Moreover, without dopaminergic medication, people with PD reduced body clearance and increased the use of a "lead-out" strategy, variability in spatial-temporal parameters, and dependency on obstacle information, increasing the risk of contact with the obstacle during circumvention.

The variability of the steps preceding obstacle avoidance (approach phase) is dependent on the height of the obstacle in people with Parkinson's disease

Gait variability may serve as a sensitive and clinically relevant parameter to quantify adjustments in walking and the changes with aging and neurological disease. Variability of steps preceding obstacle avoidance (approach phase) are important for efficiency in the task, especially in people with Parkinson's disease (PD). However, variability of gait during the approach phase to obstacle avoidance in people with PD has been rarely reported, particularly when ambulating obstacles of different heights. The aim of the present study was to investigate the effects of obstacle height on step-to-step variability (step-to-step variability provides information on the variation between the "equivalent steps" for all trials, and walking variability (indicates the within-step variability of each, providing information about the modulations between the steps performed. of spatial-temporal parameters during the approach phase to obstacle avoidance in people with PD and neurologically healthy older people. Twenty-eight older people; 15 with PD and 13 neurologically healthy individuals (control group), participated in the study. Participants were instructed to walk at their preferred speed until the end of the pathway and to avoid the obstacle when it was present. Each subject performed 10 trials of the following tasks: unobstructed walking, low obstacle avoidance (3cm length, height equal ankle’s height, 60 cm wide), intermediate obstacle (3cm length, low plus high obstacle height divided by 2, 60 cm wide) avoidance and high obstacle avoidance (3cm length, knee’s height, 60 cm wide). The obstacle was positioned 4m from to the start position. The step-to-step and walking variability of the spatial-temporal parameters (acquiring with GAITRite^®) of the four steps before obstacle avoidance were analyzed. MANOVAs were used to compare the data. PD group showed the characteristic gait deficits associated with PD. The obstacle increased the spatial-temporal variability (step–to-step and walking variability) during the approach phase to the obstacle. Specifically, both groups increased i) the step-to- step variability of the step length during low obstacle avoidance when compared to the other conditions; ii) the variability during low obstacle avoidance in the last step before obstacle (n-1) compared to higher obstacle avoidance; iii) variability during higher obstacle avoidance in further steps (n-3 and n-4). In conclusion, the presence of the obstacle during walking increased the variability of spatial-temporal parameters in older people with PD and the control group during the steps preceding obstacle avoidance. In addition motor planning (and motor adaptations) was initiated much earlier in the approach phase for the higher obstacle conditions compared to the low obstacle condition.

Do cognition and other non-motor symptoms decline similarly among patients with Parkinson's disease motor subtypes? Findings from a 5-year prospective study

Among patients with Parkinson's disease (PD), a wide range of motor and non-motor symptoms (NMS) are evident. PD is often divided into tremor dominant (TD) and postural instability gait difficulty (PIGD) motor subtypes. We evaluated the effect of disease duration and aimed to characterize whether there are differences in the deterioration of cognitive function and other NMS between the PIGD and TD subtypes. Sixty-three subjects were re-evaluated at the follow-up visit about 5 years after baseline examination. Cognitive function and other NMS were assessed. At follow-up, the PIGD and TD groups were similar with respect to medications, comorbidities and disease-related symptoms. There was a significant time effect for all measures, indicating deterioration and worsening in both groups. However, cognitive scores, particularly those related to executive function, became significantly worse in the PIGD with a more moderate decrease in the TD group. For example, the computerized global cognitive score declined in the PIGD group from 94.21 ± 11.88 to 83.91 ± 13.76, p < 0.001. This decline was significantly larger (p = 0.03) than the decrease observed in the TD group (96.56 ± 10.29 to 92.21 ± 14.20, p = 0.047). A significant group × time interaction effect was found for the change in global cognitive score (p = 0.047), the executive function index (p = 0.002) and accuracy on a motor-cognitive catch game (p = 0.008). In contrast, several NMS including depression, health-related quality of life and fear of falling deteriorated in parallel in both subtypes, with no interaction effect. The present findings highlight the difference in the natural history of the disease between the two PD "motor" subtypes. While the PIGD group demonstrated a significant cognitive decline, especially in executive functions, a more favorable course was observed in the TD subtype. This behavior was not seen in regards to the other NMS.

Classification of advanced stages of Parkinson's disease: translation into stratified treatments

Advanced stages of Parkinson's disease (advPD) still impose a challenge in terms of classification and related stage-adapted treatment recommendations. Previous concepts that define advPD by certain milestones of motor disability apparently fall short in addressing the increasingly recognized complexity of motor and non-motor symptoms and do not allow to account for the clinical heterogeneity that require more personalized approaches. Therefore, deep phenotyping approaches are required to characterize the broad-scaled, continuous and multidimensional spectrum of disease-related motor and non-motor symptoms and their progression under real-life conditions. This will also facilitate the reasoning for clinical care and therapeutic decisions, as neurologists currently have to refer to clinical trials that provide guidance on a group level; however, this does not always account for the individual needs of patients. Here, we provide an overview on different classifications for advPD that translate into critical phenotypic patterns requiring the differential therapeutic adjustments. New concepts refer to precision medicine approaches also in PD and first studies on genetic stratification for therapeutic outcomes provide a potential for more objective treatment recommendations. We define novel treatment targets that align with this concept and make use of emerging device-based assessments of real-life information on PD symptoms. As these approaches require empowerment of patients and integration into treatment decisions, we present communication strategies and decision support based on new technologies to adjust treatment of advPD according to patient demands and safety.

Gait Is Associated with Cognitive Flexibility: A Dual-Tasking Study in Healthy Older People

Objectives: To analyze which gait parameters are primarily influenced by cognitive flexibility, and whether such an effect depends on the walking condition used.

Design: Cross-sectional analysis.

Setting: Tübingen evaluation of Risk factors for Early detection of Neurodegenerative Disorders.

Participants: A total of 661 non-demented individuals (49–80 years).

Measurements: A gait assessment with four conditions was performed: a 20 m walk at convenient speed (C), at fast speed (F), at fast speed while checking boxes (FB), and while subtracting serial 7s (FS). Seven gait parameters from a wearable sensor-unit (McRoberts, Netherlands) were compared with delta Trail-Making-Test (dTMT) values, which is a measure of cognitive flexibility. Walking strategies of good and poor dTMT performers were compared by evaluating the patterns of gait parameters across conditions.

Results: Five parameters correlated significantly with the dTMT in the FS condition, two parameters in the F and FB condition, and none in the C condition. Overall correlations were relatively weak. Gait speed was the gait parameter that most strongly correlated with the dTMT (r² = 7.4%). In good, but not poor, dTMT performers differences between FB and FS were significantly different in variability-associated gait parameters.

Conclusion: Older individuals need cognitive flexibility to perform difficult walking conditions. This association is best seen in gait speed. New and particularly relevant for recognition and training of deficits is that older individuals with poor cognitive flexibility have obviously fewer resources to adapt to challenging walking conditions. Our findings partially explain gait deficits in older adults with poor cognitive flexibility.