Factors associated with falling in early, treated Parkinson's disease: The NET-PD LS1 cohort

Predicting Ambulatory Capacity in Parkinson's Disease to Analyze Progression, Biomarkers, and Trial Design

BACKGROUND

In Parkinson's disease (PD), gait and balance is impaired, relatively resistant to available treatment and associated with falls and disability. Predictive models of ambulatory progression could enhance understanding of gait/balance disturbances and aid in trial design.

OBJECTIVES

To predict trajectories of ambulatory abilities from baseline clinical data in early PD, relate trajectories to clinical milestones, compare biomarkers, and evaluate trajectories for enrichment of clinical trials.

METHODS

Data from two multicenter, longitudinal, observational studies were used for model training (Tracking Parkinson's, n = 1598) and external testing (Parkinson's Progression Markers Initiative, n = 407). Models were trained and validated to predict individuals as having a "Progressive" or "Stable" trajectory based on changes of ambulatory capacity scores from the Movement Disorders Society Unified Parkinson's Disease Rating Scale parts II and III. Survival analyses compared time-to-clinical milestones and trial outcomes between predicted trajectories.

RESULTS

On external evaluation, a support vector machine model predicted Progressive trajectories using baseline clinical data with an accuracy, weighted-F1 (proportionally weighted harmonic mean of precision and sensitivity), and sensitivity/specificity of 0.735, 0.799, and 0.688/0.739, respectively. Over 4 years, the predicted Progressive trajectory was more likely to experience impaired balance, loss of independence, impaired function and cognition. Baseline dopamine transporter imaging and select biomarkers of neurodegeneration were significantly different between predicted trajectory groups. For an 18-month, randomized (1:1) clinical trial, sample size savings up to 30% were possible when enrollment was enriched for the Progressive trajectory versus no enrichment.

CONCLUSIONS

It is possible to predict ambulatory abilities from clinical data that are associated with meaningful outcomes in people with early PD. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Efficacy of Dual-Task Training in Patients with Parkinson's Disease: A Systematic Review with Meta-Analysis

Background

Dual-task training (DTT) involves simultaneously motor and cognitive exercises.

Objectives

To determine the effectiveness of DTT, in comparison to other interventions [single-task training (STT) and usual care (UC)], on gait and balance parameters, motor impairments, activities of daily living (ADLs) and quality of life (QoL) in patients with Parkinson's disease (PD) immediately post-intervention and at 3, 6, and 12 months after therapy.

Methods

A meta-analysis was performed following PRISMA Guidelines through searching in PubMed, SCOPUS, WOS, CINAHL, SciELO and PEDro up to September 2022. We included randomized controlled trials (RCTs) that compare the effect of DTT versus STT and UC on gait (speed, step and stride length, cadence and steps per day), balance (functional and dynamic balance), motor impairments, ADLs and QoL. Methodological quality was assessed using the PEDro scale. The pooled effect was calculated through Cohen's Standardized Mean Difference (SMD) and its 95% confidence interval (95%CI).

Results

Seventeen RCTs with 826 participants and a mean PEDro score of 6.59 ± 1 points were included. In comparison to STT and UC, DTT is effective in improving walking speed (SMD 0.42, 95%CI 0.23-0.6), stride length (SMD 0.69, 95%CI 0.23-1.15), cadence (SMD 0.41, 95%CI 0.19-0.63), functional balance (SMD 1.15, 95%CI 0.92-1.4), dynamic balance (SMD -0.5, 95%CI -0.81 to -0.18) and motor impairments (SMD -0.86, 95%CI -1.25 to -0.47). No adverse effects related to DTT were reported.

Conclusions

DTT is an effective and safe therapy for improving gait, balance and motor impairments in patients with PD.

The 'Pants-Sign': A Predictor for Falling in People with Parkinson's Disease?

BACKGROUND

A history of falls is the most established predictor of future falls in people with Parkinson's disease (PD). However, predicting a first fall remains challenging.

OBJECTIVE

To assess whether experiencing difficulties putting on pants while standing is a viable predictor of future falling, and specifically a first fall, in persons with PD. We define this 'Pants-sign' as people who resort to putting on their pants only while seated.

METHODS

264 persons with PD were included. Information on the Pants-sign, history of falls, disease severity (MDS-UPDRS part III), freezing of gait (N-FOGQ > 0), cognitive function (MoCA), self-reported disability (Schwab & England scale), health-related quality of life (SF-12), Timed-Up-and-Go, and one-legged stance were determined at baseline and after one-year follow-up. The association between the Pants-sign and future falling was examined by univariate logistic regression analysis. A multivariate step-wise logistic regression with forward selection was employed to identify the strongest associations in the entire cohort and a sub-cohort of people without falls in the year prior to baseline.

RESULTS

The Pants-sign was univariably associated with a future fall (OR = 2.406, 95% CI [1.313-4.409], p = 0.004]), but was not an independent predictor in the multivariate logistic regression; predictors were higher MDS-UPDRS part III scores (OR = 1.088, 95% CI [1.056-1.121], p < 0.001] and history of falls (OR = 5.696, 95% CI [2.650-12.243], p≤0.001]. For the sub-cohort of people without falls in the previous year (n = 189), the Pants-sign was not associated with future falls.

CONCLUSIONS

The Pants-sign is simple to assess and is associated with future falling in PD but is not an independent predictor.

Acute Effects of a Haptic Anchor System on Postural Sway of Individuals with Parkinson's Disease: A Preliminary Study

Some investigators have demonstrated that an anchor system can improve postural control in elderly persons during balance tasks, but none have reported on the use of this approach in individuals with Parkinson's disease (PD). Therefore, we aimed to evaluate the effect of an anchor system on postural sway in elderly individuals with (n = 13) and without (n = 14) PD. In this cross-sectional study, we measured postural sway with a force platform based on the Clinical Test of Sensory Interaction of Balance (CTSIB). We calculated center of pressure (COP) parameters, as a function of time, based on the ellipse sway area (cm²) and evaluated self-efficacy for postural control based on the degree of difficulty in each task. With the anchor system (i.e., handheld ropes attached to weights on the floor), we observed a significant reduction in the ellipse sway area in the semi-tandem position among individuals with PD (p = .04). For participants without PD, there was no significant difference in sway with or without the anchor system in all positions. Also, for participants with PD, there was an improvement in self-efficacy for postural control associated with the anchor system in several positions while there was only a self-efficacy improvement with the anchor system in the semi-tandem position for those without PD. Acute use of a haptic anchor system reduced postural sway in the semi-tandem position in individuals with PD, and the anchor system generally improved postural control self-efficacy for body sway in individuals with PD.

The effect of galvanic vestibular stimulation on postural balance in Parkinson's disease: A systematic review and meta-analysis

People with Parkinson's disease (PD) develop postural imbalance and falls. Galvanic Vestibular Stimulation (GVS) may potentially improve postural balance in humans and hence reduce falls in PD. This systematic review and meta-analysis investigate the effects of GVS on postural balance in PD. Six separate databases and research registers were searched for cross-over design trials that evaluated the effects of GVS on postural balance in PD. We used standardized mean difference (Hedges' g) as a measure of effect size in all studies. We screened 223 studies, evaluated 14, of which five qualified for the meta-analysis. Among n = 40 patients in five studies (range n = 5 to 13), using a fixed effects model we found an effect size estimate of g = 0.43 (p < 0.001, 95% CI [0.29,0.57]). However, the test for residual heterogeneity was significant (p < 0.001), thus we used a random effects model and found a pooled effect size estimate of 0.62 (p > 0.05, 95% CI [- 0.17, 1.41], I2 = 96.21%). Egger's test was not significant and thus trim and funnel plot indicated no bias. To reduce heterogeneity, we performed sensitivity analysis and by removing one outlier study (n = 7 patients), we found an effect size estimate of 0.16 (p < 0.05, 95% CI [0.01, 0.31], I2 = 0%). Our meta-analysis found GVS has a favourable effect on postural balance in PD patients, but due to limited literature and inconsistent methodologies, this favourable effect must be interpreted with caution.

Longitudinal Cohort Study of Verbatim-Reported Postural Instability Symptoms as Outcomes for Online Parkinson’s Disease Trials

Background: The Parkinson’s Disease Patient Report of Problems (PD-PROP) captures the problems and functional impact that patients report verbatim. Online research participation and advances in language analysis have enabled longitudinal collection and classification of symptoms as trial outcomes. Objective: Analyze verbatim reports longitudinally to examine postural-instability symptoms as 1) precursors of subsequent falling and 2) newly occurring symptoms that could serve as outcome measures in randomized controlled trials. Methods: Problems reported by >25,000 PD patients in their own words were collected online in the Fox Insight observational study and classified into symptoms by natural language processing, clinical curation, and machine learning. Symptoms of gait, balance, falling, and freezing and associated reports of having fallen in the last month were analyzed over three years of longitudinal observation by a Cox regression model in a cohort of 8,287 participants. New onset of gait, balance, falling, and freezing symptoms was analyzed by Kaplan-Meier survival techniques in 4,119 participants who had not previously reported these symptoms. Results: Classified verbatim symptoms of postural instability were significant precursors of subsequent falling among participants who were older, female, and had longer PD duration. New onset of symptoms steadily increased and informed sample size estimates for clinical trials to reduce the onset of these symptoms. Conclusion: The tools to analyze symptoms reported by PD patients in their own words and capacity to enroll large numbers of research participants online support the feasibility and statistical power for conducting randomized clinical trials to detect effects of therapeutic interventions.

Interventions for preventing falls in Parkinson's disease

BACKGROUND

Most people with Parkinson's disease (PD) experience at least one fall during the course of their disease. Several interventions designed to reduce falls have been studied. An up-to-date synthesis of evidence for interventions to reduce falls in people with PD will assist with informed decisions regarding fall-prevention interventions for people with PD.

OBJECTIVES

To assess the effects of interventions designed to reduce falls in people with PD.

SEARCH METHODS

CENTRAL, MEDLINE, Embase, four other databases and two trials registers were searched on 16 July 2020, together with reference checking, citation searching and contact with study authors to identify additional studies. We also conducted a top-up search on 13 October 2021.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of interventions that aimed to reduce falls in people with PD and reported the effect on falls. We excluded interventions that aimed to reduce falls due to syncope.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane Review procedures. Primary outcomes were rate of falls and number of people who fell at least once. Secondary outcomes were the number of people sustaining one or more fall-related fractures, quality of life, adverse events and economic outcomes. The certainty of the evidence was assessed using GRADE.

MAIN RESULTS

This review includes 32 studies with 3370 participants randomised. We included 25 studies of exercise interventions (2700 participants), three studies of medication interventions (242 participants), one study of fall-prevention education (53 participants) and three studies of exercise plus education (375 participants). Overall, participants in the exercise trials and the exercise plus education trials had mild to moderate PD, while participants in the medication trials included those with more advanced disease. All studies had a high or unclear risk of bias in one or more items. Illustrative risks demonstrating the absolute impact of each intervention are presented in the summary of findings tables. Twelve studies compared exercise (all types) with a control intervention (an intervention not thought to reduce falls, such as usual care or sham exercise) in people with mild to moderate PD. Exercise probably reduces the rate of falls by 26% (rate ratio (RaR) 0.74, 95% confidence interval (CI) 0.63 to 0.87; 1456 participants, 12 studies; moderate-certainty evidence). Exercise probably slightly reduces the number of people experiencing one or more falls by 10% (risk ratio (RR) 0.90, 95% CI 0.80 to 1.00; 932 participants, 9 studies; moderate-certainty evidence).  We are uncertain whether exercise makes little or no difference to the number of people experiencing one or more fall-related fractures (RR 0.57, 95% CI 0.28 to 1.17; 989 participants, 5 studies; very low-certainty evidence). Exercise may slightly improve health-related quality of life immediately following the intervention (standardised mean difference (SMD) -0.17, 95% CI -0.36 to 0.01; 951 participants, 5 studies; low-certainty evidence). We are uncertain whether exercise has an effect on adverse events or whether exercise is a cost-effective intervention for fall prevention. Three studies trialled a cholinesterase inhibitor (rivastigmine or donepezil). Cholinesterase inhibitors may reduce the rate of falls by 50% (RaR 0.50, 95% CI 0.44 to 0.58; 229 participants, 3 studies; low-certainty evidence). However, we are uncertain if this medication makes little or no difference to the number of people experiencing one or more falls (RR 1.01, 95% CI 0.90 to 1.14230 participants, 3 studies) and to health-related quality of life (EQ5D Thermometer mean difference (MD) 3.00, 95% CI -3.06 to 9.06; very low-certainty evidence). Cholinesterase inhibitors may increase the rate of non fall-related adverse events by 60% (RaR 1.60, 95% CI 1.28 to 2.01; 175 participants, 2 studies; low-certainty evidence). Most adverse events were mild and transient in nature.  No data was available regarding the cost-effectiveness of medication for fall prevention. We are uncertain of the effect of education compared to a control intervention on the number of people who fell at least once (RR 10.89, 95% CI 1.26 to 94.03; 53 participants, 1 study; very low-certainty evidence), and no data were available for the other outcomes of interest for this comparisonWe are also uncertain (very low-certainty evidence) whether exercise combined with education makes little or no difference to the number of falls (RaR 0.46, 95% CI 0.12 to 1.85; 320 participants, 2 studies), the number of people sustaining fall-related fractures (RR 1.45, 95% CI 0.40 to 5.32,320 participants, 2 studies), or health-related quality of life (PDQ39 MD 0.05, 95% CI -3.12 to 3.23, 305 participants, 2 studies). Exercise plus education may make little or no difference to the number of people experiencing one or more falls (RR 0.89, 95% CI 0.75 to 1.07; 352 participants, 3 studies; low-certainty evidence). We are uncertain whether exercise combined with education has an effect on adverse events or is a cost-effective intervention for fall prevention.  AUTHORS' CONCLUSIONS: Exercise interventions probably reduce the rate of falls, and probably slightly reduce the number of people falling in people with mild to moderate PD.  Cholinesterase inhibitors may reduce the rate of falls, but we are uncertain if they have an effect on the number of people falling. The decision to use these medications needs to be balanced against the risk of non fall-related adverse events, though these adverse events were predominantly mild or transient in nature. Further research in the form of large, high-quality RCTs are required to determine the relative impact of different types of exercise and different levels of supervision on falls, and how this could be influenced by disease severity. Further work is also needed to increase the certainty of the effects of medication and further explore falls prevention education interventions both delivered alone and in combination with exercise.

Avaliação do risco de quedas entre pessoas com doença de Parkinson

RESUMO Objetivo identificar os fatores associados ao risco de quedas entre as pessoas com doença de Parkinson cadastradas na Associação Parkinson Santa Catarina. Método estudo transversal exploratório descritivo e de abordagem quantitativa, realizado com 53 pessoas cadastradas na Associação Parkinson Santa Catarina, no município de Florianópolis, Brasil, no período de junho a setembro de 2019. Foram aplicados questionário sociodemográfico, Escala de Hoehn e Yahr, Mini Exame do Estado Mental e Teste de Rastreio do Risco de Queda no Idoso. Os dados foram tabulados e analisados por meio do Sistema online de Ensino-Aprendizagem de Estatística SEstatNet®. Resultados foram identificados fatores de risco, como sexo, aumento da idade, redução da força muscular, instabilidade postural e diminuição da velocidade da marcha. Em relação aos estágios da doença, foi constatado que em todos houve piora da velocidade da marcha e o medo de cair é constante, aumentando com o agravamento da doença e o tempo de diagnóstico. Conclusão e implicações para a prática ao aprofundar o estudo do tema, o enfermeiro consegue compreender os acometimentos motores que levam à fragilização e à queda em pessoas com doença de Parkinson, elaborando estratégias para preveni-las.

Predictive Value of Verbatim Parkinson's Disease Patient-Reported Symptoms of Postural Instability and Falling

Background:

Postural instability is an intractable sign of Parkinson’s disease, associated with poor disease prognosis, fall risk, and decreased quality of life.

Objective:

1) Characterize verbatim reports of postural instability and associated symptoms (gait disorder, balance, falling, freezing, and posture), 2) compare reports with responses to three pre-specified questions from Part II of the Movement Disorder Society Unified Parkinson Disease Rating Scale (MDS-UPDRS), and 3) examine postural instability symptoms and MDS-UPDRS responses as predictors of future falls.

Methods:

Fox Insight research participants reported their problems attributed to PD in their own words using the Parkinson Disease Patient Reports of Problems (PD-PROP). Natural language processing, clinical curation, and data mining techniques were applied to classify text into problem domains and clinically-curated symptoms. Baseline postural instability symptoms were mapped to MDS-UPDRS questions 2.11–2.13. T-tests and chi-square tests were used to compare postural instability reporters and non-reporters, and Cochran-Armitage trend tests were used to evaluate associations between PD-PROP and MDS-UPDRS responses; survival methods were utilized to evaluate the predictive utility of PD-PROP and MDS-UPDRS responses in time-to-fall analyses.

Results:

Of participants within 10 years of PD diagnosis, 9,692 (56.0%) reported postural instability symptoms referable to gait unsteadiness, balance, falling, freezing, or posture at baseline. Postural instability symptoms were significantly associated with patient-reported measures from the MDS-UPDRS questions. Balance problems reported on PD-PROP and MDS-UPDRS 2.11–2.13 measures were predictive of future falls.

Conclusion:

Verbatim-reported problems captured by the PD-PROP and categorized by natural language processing and clinical curation and MDS-UPDRS responses predicted falls. The PD-PROP output was more granular than, and as informative as, the categorical responses.

Impact of motor subtype on non-motor symptoms and fall-related features in patients with early Parkinson's disease

AIM

Clinical implications for motor phenotypes of Parkinson's disease (PD) remain to be further elucidated, particularly at the early stages of the disease. We aimed to compare the non-motor and fall-related features between tremor-dominant (TD) and postural instability-gait difficulty (PIGD) subtypes in patients with early PD.

METHODS

PD was categorized into TD, intermediate and PIGD types, according to the literature. Not only motor symptoms, but also non-motor symptoms for global cognition, depression, anxiety, fatigue and dysautonomia, were measured in detail. In addition, fall-related features, including a previous history of falls, fear of fall measurement and gait freezing were assessed.

RESULTS

In patients with early PD (disease duration no more than 5 years), 35 patients with TD-type PD and 31 patients with PIGD-type PD were finally evaluated for the study. Compared with the TD group, the PIGD group showed higher fatigue, gastrointestinal dysfunction and fall-related parameter scores. Moreover, the PIGD scores were significantly correlated with all of those symptoms.

CONCLUSIONS

Our findings suggest that PIGD is significantly linked to fatigue, gastrointestinal dysfunction and fall-related features during the early stages of PD. Geriatr Gerontol Int 2021; 21: 416-420.

Association of fall risk factors and non-motor symptoms in patients with early Parkinson's disease

The association of non-motor symptoms (NMSs) with fall-related factors in patients with Parkinson’s disease (PD) remains to be further elucidated in the early stages of the disease. Eighty-six patients with less than 5 years of the onset of PD were retrospectively enrolled in the study. We assessed potential fall-related risk factors including (1) a history of falls during the past year (faller versus non-faller), (2) the fear of falling (FoF), and (3) the freezing of gait (FoG). Different types of NMSs were measured using the Montreal Cognitive Assessment (MoCA), the Beck Depression Inventory (BDI), the Beck Anxiety Inventory (BAI), the Parkinson’s disease Fatigue Scale (PFS), and the Scales for Outcomes in Parkinson’s disease—Autonomic dysfunction (SCOPA-AUT). The faller group (37.2%) showed higher scores for BDI, BAI, PFS, and SCOPA-AUT, compared to the non-faller group. From logistic regression analyses, the prior history of falls was related to the gastrointestinal domain of SCOPA-AUT, FoF was associated with BAI, and gastrointestinal and urinary domains of SCOPA-AUT, and FoG was linked to BAI and gastrointestinal domain of SCOPA-AUT. In conclusion, we found that fall-related risk factors in patients with early PD were highly connected with gastrointestinal dysautonomia.

Using machine learning-based analytics of daily activities to identify modifiable risk factors for falling in Parkinson's disease

BACKGROUND

Although risk factors that lead to falling in Parkinson's disease (PD) have been previously studied, the established predictors are mostly non-modifiable. A novel method for fall risk assessment may provide more insight into preventable high-risk activities to reduce future falls.

OBJECTIVES

To explore the prediction of falling in PD patients using a machine learning-based approach.

METHOD

305 PD patients, with or without a history of falls within the past month, were recruited. Data including clinical demographics, medications, and balance confidence, scaled by the 16-item Activities-Specific Balance Confidence Scale (ABC-16), were entered into the supervised machine learning models using XGBoost to explore the prediction of fallers/recurrent fallers in two separate models.

RESULTS

99 (32%) patients were fallers and 58 (19%) were recurrent fallers. The accuracy of the model to predict falls was 72% (p = 0.001). The most important factors were item 7 (sweeping the floor), item 5 (reaching on tiptoes), and item 12 (walking in a crowded mall) in the ABC-16 scale, followed by disease stage and duration. When recurrent falls were analysed, the models had higher accuracy (81%, p = 0.02). The strongest predictors of recurrent falls were item 12, 5, and 10 (walking across parking lot), followed by disease stage and current age.

CONCLUSION

Our machine learning-based study demonstrated that predictors of falling combined demographics of PD with environmental factors, including high-risk activities that require cognitive attention and changes in vertical and lateral orientations. This enables physicians to focus on modifiable factors and appropriately implement fall prevention strategies for individual patients.

Better quality of life and less caregiver strain in young-onset Parkinson's disease: a multicentre retrospective cohort study

BACKGROUND

Parkinson's disease (PD) is typically considered as a disease of the elderly. However, there is a sizeable subgroup of patients where PD starts at a younger age, known as young-onset PD (YOPD). We evaluated the differences in quality of life and caregiver strain between YOPD and later onset PD (LOPD) patients in a large cohort.

METHODS

In collaboration with the Parkinson Foundation Quality Improvement Initiative (PF-QII), we conducted a retrospective three-year analysis on 962 PD patients of the QII database (starting date May 2016). Of these, 272 patients had YOPD, and 690 had LOPD. The Parkinson's Disease Questionnaire-39 (PDQ-39) total score served as primary outcome measure. Furthermore, we analysed group differences in modified caregiver strain index (MCSI) total score, three cognition functions, and number of falls. A regression analysis adjusting for covariates was used to assess the association of age at onset with PDQ-39 and MCSI.

RESULTS

PDQ scores were better in YOPD patients, MCSI scores on social constraint were lower in YOPD patients, but scores on financial constraint were higher in this group. After adjusting for covariates, YOPD patients had better quality of life and less caregiver strain at all follow-up moments, but not at baseline. Decline over time for all outcomes was lower in the YOPD group compared to the LOPD group. Cognitive functioning and number of falls progressed slower in the YOPD group compared to the LOPD group.

CONCLUSION

Compared to LOPD patients, YOPD patients had a better quality of life, less caregiver strain, fewer falls and better cognitive functioning after their first follow-up visit, and also a slower decline over time.

Risk Factors for Falls in Patients with de novo Parkinson's Disease: A Focus on Motor and Non-Motor Symptoms

Objective

We aimed to identify risk factors for falls in patients with de novo Parkinson’s disease (PD).

Methods

Forty-six patients with de novo PD were retrospectively included in the study. We assessed details on the patients’ motor symptoms as well as non-motor symptoms using several representative scales for global cognition, depression, fatigue, and dysautonomia. Fallers and non-fallers were identified according to their history of falls during the preceding year.

Results

Twenty-two patients (45.8%) with de novo PD had a history of falls. Compared with the non-faller group, the faller group exhibited higher scores for postural instability/gait difficulty (PIGD), anxiety, fatigue, total dysautonomia, gastrointestinal dysfunction, and thermoregulatory dysfunction. Moreover, logistic regression analysis showed that falling was positively correlated with anxiety and gastrointestinal symptoms but negatively associated with the tremor scores.

Conclusion

Our findings suggest that falling in patients with de novo PD is significantly associated with PIGD/non-tremor symptoms, anxiety, and gastrointestinal dysfunction.

Falls in Synucleinopathies

Parkinson's disease (PD) and other synucleinopathies, namely dementia with Lewy bodies (DLB) and multiple system atrophy (MSA), are common degenerative neurological disorders that share synuclein pathology. Although certain cardinal features of parkinsonism, including bradykinesia and rigidity, respond well to levodopa, axial features, such as gait and balance impairment, are less reliably responsive to dopaminergic therapy and surgical interventions. Consequently, falls are common in PD and other synucleinopathies and are a major contributor toward injury and loss of independence. This underscores the need for appropriate fall risk assessment and implementation of preventative measures in all patients with parkinsonism. The aim of this review is therefore to explore modifiable and non-modifiable risk factors for falls in synucleinopathies. We next review and evaluate the evidence for pharmacological, nonpharmacological, and surgical approaches for fall prevention, and emphasize individualized and multifaceted approaches.

Exercise for Parkinson's disease

Parkinson's disease is the second most common neurodegenerative disease with a prevalence rate of 1-2 per 1000 of the population worldwide. Pharmacological management is the mainstay of treatment. Despite optimal medication, motor impairment particularly balance and gait impairment persist leading to various degree of disability and reduced quality-of-life. The present review describes motor impairment including postural impairment, gait dysfunction, reduced muscle strength and aerobic capacity and falls. Physical therapy and complementary exercises have been proven to improve motor performance and functional mobility. Evidence on the efficacy of physical therapy and complementary exercises is presented in this review. These exercises include gait training with cues, gait training with treadmill, Nordic walking, brisk walking, balance training, virtual reality interventions, Tai Chi and dance. All these treatment interventions produce short-term beneficial effects and some interventions demonstrate long-term benefit. Gait training with treadmill enhance walking performance and the effects sustain for 3-6 months. Balance training improves balance, function and reduces fall rate, and these effects carry over to at least 12 months after training ended. Sustained Tai Chi for 6 months, dance therapy for 12 months, progressive resistive training for 24 months alleviates the PD motor symptoms, suggesting that they could slow down PD progression. Based on this evidence, individuals with PD are encouraged to sustain their training in order to improve/maintain their physical ability and to combat the progression of PD.

Effects of transcranial direct current stimulation (tDCS) on balance improvement: a systematic review and meta-analysis

Background: Transcranial direct current stimulation (tDCS) has emerged as a promising therapeutic tool to improve balance and optimize rehabilitation strategies. However, current literature shows the methodological heterogeneity of tDCS protocols and results, hindering any clear conclusions about the effects of tDCS on postural control. Objective: Evaluate the effectiveness of tDCS on postural control, and identify the most beneficial target brain areas and the effect on different populations. Methods: Two independent reviewers selected randomized tDCS clinical-trials studies from PubMed, Scopus, Web of Science, and reference lists of retrieved articles published between 1998 and 2017. Most frequently reported centre of pressure (COP) variables were selected for meta-analysis. Other postural control outcomes were discussed in the review. Results: Thirty studies were included in the systematic review, and 11 were submitted to a meta-analysis. A reduction of COP displacement area has been significantly achieved by tDCS, evidencing an improvement in balance control. Individuals with cerebral palsy (CP) and healthy young adults are mostly affected by stimulation. The analysis of the impact of tDCS over different brain areas revealed a significant effect after primary motor cortex (M1) stimulation, however, with no clear results after cerebellar stimulation due to divergent results among studies. Conclusions: tDCS appears to improve balance control, more evident in healthy and CP subjects. Effects are observed when primary MI is stimulated. Cerebellar stimulation should be better investigated.

Lower Limb Rigidity Is Associated with Frequent Falls in Parkinson's Disease

Background and Objective

The role of muscle rigidity as an etiological factor of falls in Parkinson's disease (PD) is poorly understood. Our objective was to determine whether lower leg rigidity was differentially associated with frequent falls in PD compared to upper limb, neck, and total rigidity measures.

Methods

We examined the associations between Unified Parkinson's Disease Rating Scale-Part III (motor) rigidity subscores and the history of monthly or more frequent falls in 216 individuals with PD (age, 66 ± 10 years; 36% female; disease duration, 7 ± 5 years) with logistic regression.

Results

A total of 35 individuals were frequent fallers. Significant associations were identified between lower limb rigidity and frequent falls (P = 0.01) after controlling for age, sex, PD duration, total Unified Parkinson's Disease Rating Scale- Part III score, and presence of freezing of gait. No significant associations (P ≥ 0.14) were identified for total, arm, or neck rigidity.

Conclusion

Lower limb rigidity is related to frequent falls in people with PD. Further investigation may be warranted into how parkinsonian rigidity could cause falls.

Cardiovascular autonomic neuropathy and falls in Parkinson disease: a prospective cohort study

BACKGROUND

Falls represent one of the main complications of Parkinson's disease (PD), significantly lowering quality of life. Cardiovascular autonomic neuropathy (cAN) is one of the key contributing factors to PD-associated falls. However, a direct quantification of its impact on the risk of falling in PD is still lacking. In this 12-month prospective study, we sought to evaluate the association between cAN and falls.

METHODS

Fifty consecutive patients were evaluated with a standardized battery of autonomic testing, Unified Parkinson's Disease Rating Scale, push and release (P&R) test, timed up and go test, freezing of gait (FOG) questionnaire, Montreal cognitive assessment (MoCA). Dyskinesia severity and presence of REM sleep behavioral disorder (RBD) were additionally considered. Patients were followed-up for 12 months.

RESULTS

We observed a 38% prevalence of cAN. At baseline, 36% of patients reported at least one fall in the previous 6 months. This figure increased to 56% over the follow-up. After adjusting for age, disease duration, axial symptoms, MoCA and dopaminergic treatment, cAN was significantly associated with a 15-fold (OR 15.194) higher probability of falls; orthostatic hypotension (OH), the most common expression of cAN, with a 10-fold probability (OR 10.702). In addition P&R test (OR 14.021), RBD (OR 5.470) and FOG (OR 1.450) were independently associated with greater probability of falls.

CONCLUSIONS

cAN, including but not limited to OH, is a strong independent predictor of falls in PD. Future research endeavors clarifying to what extent pharmacological and non-pharmacological treatments targeting autonomic dysfunctions might reduce the risk of falls are warranted.

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.

Romberg ratio coefficient in quiet stance and postural control in Parkinson's disease

The aim of this study was to determine the function of visual afference in postural control in Parkinson patients. We enrolled 29 patients and 30 healthy controls. The stabilometry test was performed for posture and balance and Romberg ratio coefficients were calculated. In addition, the Berg Balance Scale and the 6-Minute Walking Test were administered to assess balance and functional exercise capacity; the Unified Parkinson's Disease Rating Scale was used to determine the stage of the disease; and the Short Form (SF)-36 Health Survey was given to collect information on quality of life.

RESULTS

significantly longer Center of Pressure (CoP) sway lengths were observed in the parkinson group. The Romberg index for CoP length of sway in parkinson patients was 94.3 ± 19.3%, versus 147.4 ± 120.6% for the control group. (p = 0.025).

CONCLUSION

Parkinson patients use the increase in CoP sway length and ellipse area to stabilize their balance and sight does not facilitate static postural control as in healthy subjects.