Short-distance walking speed tests in people with Parkinson disease: reliability, responsiveness, and validity

Clinical utility of the 6-min walk test for patients with moderate Parkinson's disease

The aim of this study was to test the clinical utility of the 6-min walk test (6MWT) for patients with moderate Parkinson's disease (PD) through a determination of factors related to this test. This was a descriptive, observational study carried out at a General Hospital, in-patients. Twenty-four patients with moderate PD were studied. We used Hoehn and Yahr stage ratings (HY stage), Unified Parkinson Disease Rating Scales (UPDRS) motor examination score, 6MWT, Berg Balance scale, Timed 'Up & Go' test (TUG), 10-m walk test (10-m walk speed, 10-m walk steps and cadence), and the energy cost of walking (Ec). The average HY stage was 3.1±0.5 and 6MWT was 340.8±110.9 m. TUG (r=-0.68, P<0.01) and Ec (r=-0.65, P<0.01) were correlated significantly with 6MWT. Multiple regression analysis with age, HY stage, TUG, cadence, and Ec as variables indicated a significant degree of variability in the 6MWT results (R=0.77, P<0.001). The TUG (β=-0.47, P<0.01) and Ec (β=-0.4, P<0.01) were correlated independently with the 6MWT results. In contrast, age, HY stage, and cadence were not independently correlated. The 6MWT is a simple tool for assessing walking capacity for patients with PD. In this study, we confirmed the convergent validity and clinical utility of the 6MWT for patients with moderate PD. The 6MWT is useful for clinical assessment to guide the planning of rehabilitation treatment for patients with moderate PD.

Effects of 2 Years of Exercise on Gait Impairment in People With Parkinson Disease: The PRET-PD Randomized Trial

BACKGROUND AND PURPOSE

This study presents a secondary analysis from the Progressive Resistance Exercise Training in Parkinson Disease (PRET-PD) trial investigating the effects of progressive resistance exercise (PRE) and a Parkinson disease (PD)-specific multimodal exercise program, modified Fitness Counts (mFC), on spatial, temporal, and stability-related gait impairments in people with PD.

METHODS

Forty-eight people with PD were randomized to participate in PRE or mFC 2 times a week for 24 months; 38 completed the study. Gait velocity, stride length, cadence, and double-support time were measured under 4 walking conditions (off-/on-medication, comfortable/fast speed). Ankle strength was also measured off- and on-medication. Twenty-four healthy controls provided comparison data at one time point.

RESULTS

At 24 months, there were no significant differences between exercise groups. Both groups improved fast gait velocity off-medication, cadence in all conditions, and plantarflexion strength off-/on-medication. Both groups with PD had more gait measures that approximated the healthy controls at 24 months than at baseline. Plantarflexion strength was significantly associated with gait velocity and stride length in people with PD at baseline and 24 months, but changes in strength were not associated with changes in gait.

DISCUSSION AND CONCLUSIONS

Twenty-four months of PRE and mFC were associated with improved off-medication fast gait velocity and improved cadence in all conditions, which is important because temporal gait measures can be resistant to medications. Spatial and stability-related measures were resistant to long-term improvements, but did not decline over 24 months. Strength gains did not appear to transfer to gait.Video Abstract available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A161).

A Tandem Cycling Program: Feasibility and Physical Performance Outcomes in People With Parkinson Disease

BACKGROUND AND PURPOSE

Individuals with Parkinson disease (PD) have motor and nonmotor impairments that interfere with exercise participation. The purpose of this study was to examine the feasibility and physical performance outcomes of a community-based indoor tandem cycling program that was designed to facilitate a higher cadence, consistency, and intensity of training.

METHODS

Forty-one participants with mild to moderate PD were enrolled. A high-cadence cycling protocol using mechanically augmented (or forced) exercise on a tandem bicycle was adapted for our program. Participants cycled 3 times per week for 10 weeks. Feasibility measures included program retention, attendance, and adverse events, as well as the ability to reach training goals for heart rate (HR) and cadence. Physical performance outcomes included the Berg Balance Scale (BBS), Short Physical Performance Battery (SPPB), Five-Times-Sit-to-Stand (FTSTS) Test, Timed Up and Go (TUG), and gait parameters during usual and fast-paced walking.

RESULTS

Program feasibility was demonstrated with a high attendance rate (96%) and retention rate (100%). There were no adverse events. The majority of participants reached their exercise training goals for target HR (87%) and cadence (95%). Statistically significant physical performance improvement (P < 0.05) was observed across domains of gait, balance, and mobility, suggesting a slowing or reversal of functional decline as a result of this cycling program.

DISCUSSION AND CONCLUSION

Program feasibility and improved physical performance outcomes were demonstrated in individuals with mild to moderate PD participating in a community-based indoor tandem cycling program.Video Abstract available for more insights from the authors (see supplemental digital content 1, http://links.lww.com/JNPT/A146).

Does Nordic Walking restore the temporal organization of gait variability in Parkinson's disease?

BACKGROUND

Gait disorders of Parkinson's disease (PD) are characterized by the breakdown of the temporal organization of stride duration variability that was tightly associated to dynamic instability in PD. Activating the upper body during walking, Nordic Walking (NW) may be used as an external cueing to improve spatiotemporal parameters of gait, such as stride length or gait variability, in PD. The aim of this study was to evaluate the beneficial effects of NW on temporal organization of gait variability and spatiotemporal gait variables in PD.

METHODS

Fourteen mild to moderate PD participants and ten age-matched healthy subjects performed 2 × 12 min overground walking sessions (with and without pole in a randomized order) at a comfortable speed. Gait speed, cadence, step length and temporal organization (i.e. long-range autocorrelations; LRA) of stride duration variability were studied on 512 consecutive gait cycles using a unidimensional accelerometer placed on the malleola of the most affected side in PD patients and of the dominant side in healthy controls. The presence of LRA was determined using the Rescaled Range Analysis (Hurst exponent) and the Power Spectral Density (α exponent). To assess NW and disease influences on gait, paired t-tests, Z-score and a two-way (pathological condition x walking condition) ANOVA repeated measure were used.

RESULTS

Leading to significant improvement of LRA, NW enhances step length and reduces gait cadence without any change in gait speed in PD. Interestingly, LRA and step length collected from the NW session are similar to that of the healthy population.

CONCLUSION

This cross-sectional controlled study demonstrates that NW may constitute a powerful way to struggle against the randomness of PD gait and the typical gait hypokinesia. Involving a voluntary intersegmental coordination, such improvement could also be due to the upper body rhythmic movements acting as rhythmical external cue to bypass their defective basal ganglia circuitries.

ETHICS COMMITTEE'S REFERENCE NUMBER

B403201318916 TRIAL REGISTRATION: NCT02419768.

Are the average gait speeds during the 10meter and 6minute walk tests redundant in Parkinson disease?

We investigated the relationships between average gait speed collected with the 10Meter Walk Test (Comfortable and Fast) and 6Minute Walk Test (6MWT) in 346 people with Parkinson disease (PD) and how the relationships change with increasing disease severity. Pearson correlation and linear regression analyses determined relationships between 10Meter Walk Test and 6MWT gait speed values for the entire sample and for sub-samples stratified by Hoehn & Yahr (H&Y) stage I (n=53), II (n=141), III (n=135) and IV (n=17). We hypothesized that redundant tests would be highly and significantly correlated (i.e. r>0.70, p<0.05) and would have a linear regression model slope of 1 and intercept of 0. For the entire sample, 6MWT gait speed was significantly (p<0.001) related to the Comfortable 10 Meter Walk Test (r=0.75) and Fast 10Meter Walk Test (r=0.79) gait speed, with 56% and 62% of the variance in 6MWT gait speed explained, respectively. The regression model of 6MWT gait speed predicted by Comfortable 10 Meter Walk gait speed produced slope and intercept values near 1 and 0, respectively, especially for participants in H&Y stages II-IV. In contrast, slope and intercept values were further from 1 and 0, respectively, for the Fast 10Meter Walk Test. Comfortable 10 Meter Walk Test and 6MWT gait speeds appeared to be redundant in people with moderate to severe PD, suggesting the Comfortable 10 Meter Walk Test can be used to estimate 6MWT distance in this population.

The Mini-BESTest: a review of psychometric properties

The Mini-Balance Evaluation Systems Test (Mini-BESTest) has been identified as the most comprehensive balance measure for community-dwelling adults and elderly individuals. It can be used to assess balance impairments in several other conditions, mainly Parkinson's disease and stroke. Despite increasing use of the Mini-BESTest since it was first published 5 years ago, no systematic review synthesizing its psychometric properties is available. The aim of this study was to provide a comprehensive review of the psychometric properties of the Mini-BESTest when administered to patients with balance deficits because of different diseases. A literature search was performed on articles published before July 2015 in journals indexed by MEDLINE and Scopus databases. The search produced 98 papers, 24 of which fulfilled the inclusion criteria for this review. Most papers (n=19) focused on patients affected by neurological diseases, mainly Parkinson's disease. In 21 papers, the psychometric characteristics were analyzed using Classical Test Theory methods and in only three papers was Rasch analysis carried out. This review shows the interest of researchers in the Mini-BESTest despite the short time frame since its first publication. The Mini-BESTest is used widely in both clinical practice and research. The results support the reliability, validity, and responsiveness of this instrument and it can be considered a standard balance measure. However, it would be valuable to learn more about how this scale performs in different diseases causing balance deficits and to better define the minimal clinically important difference for each disease.

Test-Retest Reliability of Dual-Task Outcome Measures in People With Parkinson Disease

BACKGROUND

Dual-task (DT) training is gaining ground as a physical therapy intervention in people with Parkinson disease (PD). Future studies evaluating the effect of such interventions need reliable outcome measures. To date, the test-retest reliability of DT measures in patients with PD remains largely unknown.

OBJECTIVE

The purpose of this study was to assess the reliability of DT outcome measures in patients with PD.

DESIGN

A repeated-measures design was used.

METHODS

Patients with PD ("on" medication, Mini-Mental State Examination score ≥24) performed 2 cognitive tasks (ie, backward digit span task and auditory Stroop task) and 1 functional task (ie, mobile phone task) in combination with walking. Tasks were assessed at 2 time points (same hour) with an interval of 6 weeks. Test-retest reliability was assessed for gait while performing each secondary task (DT gait) for both cognitive tasks while walking (DT cognitive) and for the functional task while walking (DT functional).

RESULTS

Sixty-two patients with PD (age=39-89 years, Hoehn and Yahr stages II-III) were included in the study. Intraclass correlation coefficients (ICCs) showed excellent reliability for DT gait measures, ranging between .86 and .95 when combined with the digit span task, between .86 and .95 when combined with the auditory Stroop task, and between .72 and .90 when combined with the mobile phone task. The standard error of measurements for DT gait speed varied between 0.06 and 0.08 m/s, leading to minimal detectable changes between 0.16 and 0.22 m/s. With regard to DT cognitive measures, reaction times showed good-to-excellent reliability (digit span task: ICC=.75; auditory Stroop task: ICC=.82).

LIMITATIONS

The results cannot be generalized to patients with advanced disease or to other DT measures.

CONCLUSIONS

In people with PD, DT measures proved to be reliable for use in clinical studies and look promising for use in clinical practice to assess improvements after DT training. Large effects, however, are needed to obtain meaningful effect sizes.

Effects of supervised slackline training on postural instability, freezing of gait, and falls efficacy in people with Parkinson's disease

PURPOSE

The aim of this study was to assess whether supervised slackline training reduces the risk of falls in people with Parkinson's disease (PD).

METHODS

Twenty-two patients with idiopathic PD were randomized into experimental (EG, N = 11) and control (CG, N = 11) groups. Center of Pressure (CoP), Freezing of Gait (FOG), and Falls Efficacy Scale (FES) were assessed at pre-test, post-test and re-test. Rate perceived exertion (RPE, Borg's 6-20 scale) and local muscle perceived exertion (LRPE) were also assessed at the end of the training sessions.

RESULTS

The EG group showed significant improvements in FOG and FES scores from pre-test to post-test. Both decreased at re-test, though they did not return to pre-test levels. No significant differences were detected in CoP parameters. Analysis of RPE and LRPE scores revealed that slackline was associated with minimal fatigue and involved the major lower limb and lumbar muscles.

CONCLUSIONS

These findings suggest that slacklining is a simple, safe, and challenging training and rehabilitation tool for PD patients. It could be introduced into their physical activity routine to reduce the risk of falls and improve confidence related to fear of falling. Implications for Rehabilitation Individuals with Parkinson's disease (PD) are twice as likely to have falls compared to patients with other neurological conditions. This study support slackline as a simple, safe, and challenging training and rehabilitation tool for people with PD, which reduce their risk of falls and improve confidence related to fear of falling. Slackline in people with PD yields a low tiredness or fatigue impact and involves the major lower limb and lumbar muscles.

Concerns About Falling in Parkinson's Disease: Associations with Disabilities and Personal and Environmental Factors

BACKGROUND

Fear of falling can be conceptualized in different ways, e.g., as concerns about falling or low fall-related self-efficacy. It is common in people with Parkinson's disease (PD), and there is growing knowledge about its contributing factors. However, previous multivariate studies have mainly focused on fear of falling in relation to PD-related disabilities, and less is known about the associations between fear of falling and personal and environmental factors.

OBJECTIVE

To identify explanatory factors of concerns about falling in people with PD by focusing on personal and environmental factors as well as PD-related disabilities.

METHODS

Data were collected from 241 persons with PD (39% women, median age 70 years, PD duration 8 years). Concerns about falling (assessed with the Falls Efficacy Scale-International, FES-I; categorized into low, moderate, or high concerns) were used as the dependent variable in a multivariate ordinal regression analysis. Personal factors, environmental factors and PD-related disabilities constituted independent variables.

RESULTS

Low, moderate and high concerns about falling were reported by 29% , 24% and 47% of the participants, respectively. Walking difficulties, orthostatism, motor symptoms, age, and fatigue (presented in order of importance) were significant (p <  0.05) explanatory factors of concerns about falling.

CONCLUSIONS

Several factors significantly explained concerns about falling in people with PD. Walking difficulties was by far the strongest explanatory factor. This suggests that minimizing walking difficulties should be a primary target when aiming at reducing concerns about falling in people with PD.

The effects of motor rehabilitation training on clinical symptoms and serum BDNF levels in Parkinson’s disease subjects

Increasing evidence suggests that motor rehabilitation may delay Parkinson’s disease (PD) progression. Moreover, parallel treatments in animals up-regulate brain-derived neurotrophic factor (BDNF). Thus, we investigated the effect of a motor rehabilitation protocol on PD symptoms and BDNF serum levels. Motor rehabilitation training consisted of a cycle of 20 days/month of physiotherapy divided in 3 daily sessions. Clinical data were collected at the beginning, at the end, and at 90 days follow-up. BDNF serum levels were detected by ELISA at 0, 7, 14, 21, 30, and 90 days. The follow-up period had a duration of 60 days (T30–T90). The results showed that at the end of the treatment (day 30), an improvement in extrapyramidal signs (UPDRS III; UPDRS III – Gait and Balance items), motor (6 Minute Walking Test), and daily living activities (UPDRS II; PDQ-39) was observed. BDNF levels were increased at day 7 as compared with baseline. After that, no changes in BDNF were observed during the treatment and in the successive follow-up. This study demonstrates that motor rehabilitation training is able to ameliorate PD symptoms and to increase temporarily BDNF serum levels. The latter effect may potentially contribute to the therapeutic action.

Measurement instruments to assess posture, gait, and balance in Parkinson's disease: Critique and recommendations

BACKGROUND

Disorders of posture, gait, and balance in Parkinson's disease (PD) are common and debilitating. This MDS-commissioned task force assessed clinimetric properties of existing rating scales, questionnaires, and timed tests that assess these features in PD.

METHODS

A literature review was conducted. Identified instruments were evaluated systematically and classified as "recommended," "suggested," or "listed." Inclusion of rating scales was restricted to those that could be used readily in clinical research and practice.

RESULTS

One rating scale was classified as "recommended" (UPDRS-derived Postural Instability and Gait Difficulty score) and 2 as "suggested" (Tinetti Balance Scale, Rating Scale for Gait Evaluation). Three scales requiring equipment (Berg Balance Scale, Mini-BESTest, Dynamic Gait Index) also fulfilled criteria for "recommended" and 2 for "suggested" (FOG score, Gait and Balance Scale). Four questionnaires were "recommended" (Freezing of Gait Questionnaire, Activities-specific Balance Confidence Scale, Falls Efficacy Scale, Survey of Activities, and Fear of Falling in the Elderly-Modified). Four tests were classified as "recommended" (6-minute and 10-m walk tests, Timed Up-and-Go, Functional Reach).

CONCLUSION

We identified several questionnaires that adequately assess freezing of gait and balance confidence in PD and a number of useful clinical tests. However, most clinical rating scales for gait, balance, and posture perform suboptimally or have been evaluated insufficiently. No instrument comprehensively and separately evaluates all relevant PD-specific gait characteristics with good clinimetric properties, and none provides separate balance and gait scores with adequate content validity for PD. We therefore recommend the development of such a PD-specific, easily administered, comprehensive gait and balance scale that separately assesses all relevant constructs. © 2016 International Parkinson and Movement Disorder Society.

Gait speed and related factors in Parkinson's disease

[Purpose] The aim of this study was to investigate the relationship between gait speed and various factors in ambulatory patients with idiopathic Parkinson’s disease. [Subjects] Fifty ambulatory patients with idiopathic Parkinson’s disease who were admitted to an outpatient clinic were included in this cross-sectional study. [Methods] The Hoehn and Yahr Scale was used for measurement of the disease severity. Gait speed was measured by the 10-Meter Walk Test. Mobility status was assessed by Timed Up and Go Test. The Hospital Anxiety and Depression Scale was used for evaluation of emotional state. Cognitive status was examined with the Mini-Mental State Examination. The Downton Index was used for fall risk assessment. Balance was evaluated with the Berg Balance Scale. Comorbidity was measured with the Cumulative Illness Rating Scale. The 36-Item Short Form Health Survey was completed for measurement of quality of life. [Results] The mean age was 66.7 (47–83) years. Twenty-eight (56%) patients were men. Gait speed was correlated positively with height, male gender, Mini-Mental Examination score, Berg Balance Scale score and physical summary scores of the 36-Item Short Form Health Survey. On the other hand, there was a negative correlation between gait speed and age, disease severity, TUG time, Downton Index, fear of falling, previous falls and the anxiety and depression scores of the Hospital Anxiety and Depression Scale. There was no correlation between gait speed and comorbidity. [Conclusion] The factors related with the slower gait speed are, elder age, clinically advanced disease, poor mobility, fear of falling, falling history, higher falling risk, and mood disorder.

Pilot study of atomoxetine in patients with Parkinson's disease and dopa-unresponsive Freezing of Gait

Background

Freezing of gait (FoG) is a common and debilitating condition in Parkinson’s disease (PD) associated with executive dysfunction. A subtype of FoG does not respond to dopaminergic therapy and may be related to noradrenergic deficiency. This pilot study explores the effects of atomoxetine on gait in PD patients with dopa-unresponsive FoG using a novel paradigm for objective gait assessment.

Findings

Ten patients with PD and dopa-unresponsive FoG were enrolled in this eight-week open label pilot study. Assessments included an exploratory gait analysis protocol that quantified spatiotemporal parameters during straight-away walking and turning, while performing a dual task. Clinical, and subjective assessments of gait, quality of life, and safety were also administered. The primary outcome was a validated subjective assessment for FoG (FOG-Q). Atomoxetine was well tolerated, however, no significant change was observed in the primary outcome. The gait analysis protocol correlated well with clinical scales, but not with subjective assessments. DBS patients were more likely to increase gait velocity (p = 0.033), and improved in other clinical assessments.

Conclusions

Objective gait analysis protocols assessing gait while dual tasking are feasible and useful for this patient population, and may be superior correlates of FoG severity than subjective measures. These findings can inform future trials in this population.

Walking speed: the functional vital sign

Walking speed (WS) is a valid, reliable, and sensitive measure appropriate for assessing and monitoring functional status and overall health in a wide range of populations. These capabilities have led to its designation as the "sixth vital sign". By synthesizing the available evidence on WS, this scholarly review article provides clinicians with a reference tool regarding this robust measure. Recommendations on testing procedures for assessing WS, including optimal distance, inclusion of acceleration and deceleration phases, instructions, and instrumentation are given. After assessing an individual's WS, clinicians need to know what this value represents. Therefore, WS cut-off values and the corresponding predicted outcomes, as well as minimal detectable change values for specific populations and settings are provided.