Abigail L. Leddy

Utility of the Mini-BESTest, BESTest, and BESTest Sections for Balance Assessments in Individuals With Parkinson Disease

Background and Purpose: The Balance Evaluation Systems Test(BESTest) has been shown to be a reliable and valid measure of balance in individuals with Parkinson disease (PD). A less time-consuming assessment may increase clinical utility. We compared the discriminative fall risk ability of the Mini-BESTest with that of the BESTest and determined the reliability and normal distribution of scores for each section of the BESTest and the Mini-BESTest in individuals with PD. Methods: Eighty individuals with idiopathic PD were assessed using the BESTest and Mini-BESTest. A faller was defined as an individual with 2 or more falls in the prior 6 months. Subsets of individuals were used to determine interrater (n = 15) and test-retest reliability (n = 24). Results: The Mini-BESTest, total BESTest score, and all sections of the BESTest showed a significant difference between the average scores of fallers and nonfallers. For both the Mini-BESTest and BESTest, interrater (intraclass correlation ICC ≥ 0.91) and test-retest (ICC ≥ 0.88) reliability was high. The Mini-BESTest and BESTest were highly correlated (r = 0.955). Accuracy of identifying a faller was comparable for the Mini-BESTest and BESTest (area under the receiver operating characteristic plots = 0.86 and 0.84, respectively). Discussion: No specific section of the BESTest captured the primary balance deficit for individuals with PD. The posttest probabilities for discriminating fallers versus nonfallers were comparable-to-slightly stronger when using the Mini-BESTest. Conclusion: Although the Mini-BESTest has fewer than half of the items in the BESTest and takes only 15 minutes to complete, it is as reliable as the BESTest and has comparable-to-slightly greater discriminative properties for identifying fallers in individuals with PD.

Five Times Sit-to-Stand Test Performance in Parkinson's Disease

OBJECTIVES To (1) determine intrarater and test-retest reliability of the Five times sit-to-stand test (FTSTS) in Parkinsons disease (PD), (2) characterize FTSTS performance in PD at different disease stages, (3) determine predictors of FTSTS performance in PD, and (4) determine the utility of the FTSTS for discriminating between fallers and nonfallers with PD, identifying an appropriate cutoff score to delineate between these groups. DESIGN Measurement study of community-dwelling individuals with idiopathic PD. SETTING A medical school laboratory. PARTICIPANTS Participants (N=82) were recruited via population-based sampling. The final sample included 80 participants. Two were excluded because of exclusion criteria and an unrelated illness, respectively. INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES FTSTS time (seconds) was the primary outcome measure. Secondary outcome measures included the Mini-Balance Evaluation Systems Test (Mini-BEST), Maximal Voluntary Isometric Contraction-Quadriceps, 9-Hole Peg Test (9HPT), 6-minute walk, Freezing of Gait Questionnaire, Activities-Specific Balance Confidence Scale, Physical Activity Scale for the Elderly, Parkinsons Disease Questionnaire-39, and Movement Disorders Society-Unified Parkinsons Disease Rating Scale. RESULTS Interrater and test-retest reliability for the FTSTS were high (intraclass correlation coefficients: .99 and .76, respectively). Mean FTSTS performance was 20.25 ± 14.12 seconds. All mobility measures were significantly correlated with FTSTS (P<.01). The Mini-BEST and 9HPT together explained 53% of the variance in FTSTS. Receiver operating characteristic analysis determined a cutoff of 16.0 seconds (sensitivity, .75; specificity, .68) for discriminating between fallers and nonfallers, with an area under the curve of .77. CONCLUSIONS The FTSTS is a quick, easily administered measure that is useful for gross determination of fall risk in individuals with PD.

Accuracy of Fall Prediction in Parkinson Disease: Six-Month and 12-Month Prospective Analyses

Introduction. We analyzed the ability of four balance assessments to predict falls in people with Parkinson Disease (PD) prospectively over six and 12 months. Materials and Methods. The BESTest, Mini-BESTest, Functional Gait Assessment (FGA), and Berg Balance Scale (BBS) were administered to 80 participants with idiopathic PD at baseline. Falls were then tracked for 12 months. Ability of each test to predict falls at six and 12 months was assessed using ROC curves and likelihood ratios (LR). Results. Twenty-seven percent of the sample had fallen at six months, and 32% of the sample had fallen at 12 months. At six months, areas under the ROC curve (AUC) for the tests ranged from 0.8 (FGA) to 0.89 (BESTest) with LR+ of 3.4 (FGA) to 5.8 (BESTest). At 12 months, AUCs ranged from 0.68 (BESTest, BBS) to 0.77 (Mini-BESTest) with LR+ of 1.8 (BESTest) to 2.4 (BBS, FGA). Discussion. The various balance tests were effective in predicting falls at six months. All tests were relatively ineffective at 12 months. Conclusion. This pilot study suggests that people with PD should be assessed biannually for fall risk.

Comparative Utility of the BESTest, Mini-BESTest, and Brief-BESTest for Predicting Falls in Individuals With Parkinson Disease: A Cohort Study

Background The newly developed Brief–Balance Evaluation System Test (Brief-BESTest) may be useful for measuring balance and predicting falls in individuals with Parkinson disease (PD). Objectives The purposes of this study were: (1) to describe the balance performance of those with PD using the Brief-BESTest, (2) to determine the relationships among the scores derived from the 3 versions of the BESTest (ie, full BESTest, Mini-BESTest, and Brief-BESTest), and (3) to compare the accuracy of the Brief-BESTest with that of the Mini-BESTest and BESTest in identifying recurrent fallers among people with PD. Design This was a prospective cohort study. Methods Eighty participants with PD completed a baseline balance assessment. All participants reported a fall history during the previous 6 months. Fall history was again collected 6 months (n=51) and 12 months (n=40) later. Results At baseline, participants had varying levels of balance impairment, and Brief-BESTest scores were significantly correlated with Mini-BESTest (r=.94, P<.001) and BESTest (r=.95, P<.001) scores. Six-month retrospective fall prediction accuracy of the Brief-BESTest was moderately high (area under the curve [AUC]=0.82, sensitivity=0.76, and specificity=0.84). Prospective fall prediction accuracy over 6 months was similarly accurate (AUC=0.88, sensitivity=0.71, and specificity=0.87), but was less sensitive over 12 months (AUC=0.76, sensitivity=0.53, and specificity=0.93). Limitations The sample included primarily individuals with mild to moderate PD. Also, there was a moderate dropout rate at 6 and 12 months. Conclusions All versions of the BESTest were reasonably accurate in identifying future recurrent fallers, especially during the 6 months following assessment. Clinicians can reasonably rely on the Brief-BESTest for predicting falls, particularly when time and equipment constraints are of concern.

Feasibility and Potential Efficacy of High-Intensity Stepping Training in Variable Contexts in Subacute and Chronic Stroke

Background. Previous data suggest that the amount and aerobic intensity of stepping training may improve walking poststroke. Recent animal and human studies suggest that training in challenging and variable contexts can also improve locomotor function. Such practice may elicit substantial stepping errors, although alterations in locomotor strategies to correct these errors could lead to improved walking ability. Objective. This unblinded pilot study was designed to evaluate the feasibility and preliminary efficacy of providing stepping practice in variable, challenging contexts (tasks and environments) at high aerobic intensities in participants >6 months and 1-6 months post-stroke. Methods. A total of 25 participants (gait speeds <0.9 m/s with no more than moderate assistance) participated in ≤40 training sessions (duration of 1 hour) within 10 weeks. Stepping training in variable, challenging contexts was performed at 70% to 80% heart rate reserve, with feasibility measures of total steps/session, ability to achieve targeted intensities, patient tolerance, dropouts, and adverse events. Gait speed, symmetry, and 6-minute walk were measured every 4 to 5 weeks or 20 sessions, with a 3-month follow-up (F/U). Results. In all, 22 participants completed ≥4 training weeks, averaging 2887 ± 780 steps/session over 36 ± 5.8 sessions. Self-selected (0.38 ± 0.27 to 0.66 ± 0.35 m/s) and fastest speed (0.51 ± 0.40 to 0.99 ± 0.58 m/s), paretic single-limb stance (20% ± 5.9% to 25% ± 6.4%), and 6-minute walk (141 ± 99 to 260 ± 146 m) improved significantly at posttraining. Conclusions. This preliminary study suggests that stepping training at high aerobic intensities in variable contexts was tolerated by participants poststroke, with significant locomotor improvements. Future studies should delineate the relative contributions of amount, intensity, and variability of stepping training to maximize outcomes.

Variable Intensive Early Walking Poststroke (VIEWS): A Randomized Controlled Trial

Background. Converging evidence suggests that the amount of stepping practice is an important training parameter that influences locomotor recovery poststroke. More recent data suggest that stepping intensity and variability are also important, although such strategies are often discouraged early poststroke. Objective. The present study examined the efficacy of high-intensity, variable stepping training on walking and nonwalking outcomes in individuals 1 to 6 months poststroke as compared with conventional interventions. Methods. Individuals with unilateral stroke (mean duration = 101 days) were randomized to receive ≤40, 1-hour experimental or control training sessions over 10 weeks. Experimental interventions consisted only of stepping practice at high cardiovascular intensity (70%-80% heart rate reserve) in variable contexts (tasks or environments). Control interventions were determined by clinical physical therapists and supplemented using standardized conventional strategies. Blinded assessments were obtained at baseline, midtraining, and posttraining with a 2-month follow-up. Results. A total of 32 individuals (15 experimental) received different training paradigms that varied in the amount, intensity, and types of tasks performed. Primary outcomes of walking speed (experimental, 0.27 ± 0.22 m/s vs control, 0.09 ± 0.09 m/s) and distances (119 ± 113 m vs 30 ± 32 m) were different between groups, with stepping amount and intensity related to these differences. Gains in temporal gait symmetry and self-reported participation scores were greater following experimental training, without differences in balance or sit-to-stand performance. Conclusion. Variable intensive stepping training resulted in greater improvements in walking ability than conventional interventions early poststroke. Future studies should evaluate the relative contributions of these training parameters.

Effects of Dynamic Stepping Training on Nonlocomotor Tasks in Individuals Poststroke

Background During the physical rehabilitation of individuals poststroke, therapists are challenged to provide sufficient amounts of task-specific practice in order to maximize outcomes of multiple functional skills within limited visits. Basic and applied studies have suggested that training of one motor task may affect performance of biomechanically separate tasks that utilize overlapping neural circuits. However, few studies have explicitly investigated the impact of training one functional task on separate, nonpracticed tasks. Objective The purpose of this preliminary study was to investigate the potential gains in specific nonlocomotor assessments in individuals poststroke following only stepping training of variable, challenging tasks at high aerobic intensities. Methods Individuals with locomotor deficits following subacute and chronic stroke (n=22) completed a locomotor training paradigm using a repeated-measures design. Practice of multiple stepping tasks was provided in variable environments or contexts at high aerobic intensities for ≥40 sessions over 10 weeks. The primary outcome was timed Five-Times Sit-to-Stand Test (5XSTS) performance, with secondary measures of sit-to-stand kinematics and kinetics, clinical assessment of balance, and isometric lower limb strength. Results Participants improved their timed 5XSTS performance following stepping training, with changes in selected biomechanical measures. Statistical and clinically meaningful improvements in balance were observed, with more modest changes in paretic leg strength. Conclusions The present data suggest that significant gains in selected nonlocomotor tasks can be achieved with high-intensity, variable stepping training. Improvements in nonpracticed tasks may minimize the need to practice multiple tasks within and across treatment sessions.

External validation of a simple clinical tool used to predict falls in people with Parkinson disease

BACKGROUND Assessment of fall risk in an individual with Parkinson disease (PD) is a critical yet often time consuming component of patient care. Recently a simple clinical prediction tool based only on fall history in the previous year, freezing of gait in the past month, and gait velocity <1.1 m/s was developed and accurately predicted future falls in a sample of individuals with PD. METHODS We sought to externally validate the utility of the tool by administering it to a different cohort of 171 individuals with PD. Falls were monitored prospectively for 6 months following predictor assessment. RESULTS The tool accurately discriminated future fallers from non-fallers (area under the curve [AUC] = 0.83; 95% CI 0.76-0.89), comparable to the developmental study. CONCLUSION The results validated the utility of the tool for allowing clinicians to quickly and accurately identify an individuals risk of an impending fall.

Balance differences in people with Parkinson disease with and without freezing of gait

BACKGROUND Freezing of gait (FOG) is a relatively common and remarkably disabling impairment associated with Parkinson disease (PD). Laboratory-based measures indicate that individuals with FOG (PD+FOG) have greater balance deficits than those without FOG (PD-FOG). Whether such differences also can be detected using clinical balance tests has not been investigated. We sought to determine if balance and specific aspects of balance, measured using Balance Evaluation Systems Test (BESTest), differs between PD+FOG and PD-FOG. Furthermore, we aimed to determine if time-efficient clinical balance measures (i.e. Mini-BESTest, Berg Balance Scale (BBS)) could detect balance differences between PD+FOG and PD-FOG. METHODS Balance of 78 individuals with PD, grouped as either PD+FOG (n=32) or PD-FOG (n=46), was measured using the BESTest, Mini-BESTest, and BBS. Between-groups comparisons were conducted for these measures and for the six sections of the BESTest using analysis of covariance. A PD composite score was used as a covariate. RESULTS Controlling for motor sign severity, PD duration, and age, PD+FOG had worse balance than PD-FOG when measured using the BESTest (p=0.008, F=7.35) and Mini-BESTest (p=0.002, F=10.37), but not the BBS (p=0.27, F=1.26). BESTest section differences were noted between PD+FOG and PD-FOG for reactive postural responses (p<0.001, F=14.42) and stability in gait (p=0.003, F=9.18). CONCLUSIONS The BESTest and Mini-BESTest, which specifically assessed reactive postural responses and stability in gait, were more likely than the BBS to detect differences in balance between PD+FOG and PD-FOG. Because it is more time efficient to administer, the Mini-BESTest may be the preferred tool for assessing balance deficits associated with FOG.

Detecting and Predicting Balance Decline in Parkinson Disease: a Prospective Cohort Study

BACKGROUND The natural progression of balance decline in individuals with Parkinson disease (PD) is not well understood. OBJECTIVES We aimed to: 1) compare the utility of three standardized clinical measures for detecting balance decline over 1-year, 2) identify components of balance susceptible to decline, and 3) identify factors useful for predicting future balance decline. METHODS Eighty people with PD (59% male; mean age 68.2 ± 9.3; Hoehn & Yahr range I-IV) completed Balance Evaluation Systems Test (BESTest), Mini-BESTest, and Berg Balance Scale (BBS) assessments. Baseline predictor variables included the MDS-UPDRS III sub-score, presence of freezing, 6-month fall history, age, gender, and physical activity. Balance and MDS-UPDRS III assessments were repeated at 6 (n = 51) and 12 months (n = 44). RESULTS BESTest and Mini-BESTest score declined over 6 and 12 months (P < 0.01). Postural responses, stability limits, and sensory orientation were most susceptible to decline. BBS score did not change (P > 0.01). MDS-UPDRS III score was unchanged over 6 months (P > 0.01), but declined over 12 months (P < 0.01). Change in BESTest score over 6 months was related to baseline MDS-UPDRS III, H&Y, freezing, and fall history (P < 0.05). Change in BESTest score over 12 months was related to baseline MDS-UPDRS III and freezing (P < 0.05). Change in Mini-BESTest over 12 months was related to baseline MDS-UPDRS III and age (P < 0.05). CONCLUSIONS The BESTest and Mini-BESTest were responsive to balance decline in individuals with PD and helped to identify decline in underlying balance components. Disease severity and freezing most consistently predicted balance decline in persons with PD.