V. Hetherington

Cueing training in the home improves gait-related mobility in Parkinson’s disease: the RESCUE trial

Objectives: Gait and mobility problems are difficult to treat in people with Parkinson’s disease. The Rehabilitation in Parkinson’s Disease: Strategies for Cueing (RESCUE) trial investigated the effects of a home physiotherapy programme based on rhythmical cueing on gait and gait-related activity. Methods: A single-blind randomised crossover trial was set up, including 153 patients with Parkinson’s disease aged between 41 and 80 years and in Hoehn and Yahr stage II–IV. Subjects allocated to early intervention (n = 76) received a 3-week home cueing programme using a prototype cueing device, followed by 3 weeks without training. Patients allocated to late intervention (n = 77) underwent the same intervention and control period in reverse order. After the initial 6 weeks, both groups had a 6-week follow-up without training. Posture and gait scores (PG scores) measured at 3, 6 and 12 weeks by blinded testers were the primary outcome measure. Secondary outcomes included specific measures on gait, freezing and balance, functional activities, quality of life and carer strain. Results: Small but significant improvements were found after intervention of 4.2% on the PG scores (p = 0.005). Severity of freezing was reduced by 5.5% in freezers only (p = 0.007). Gait speed (p = 0.005), step length (p<0.001) and timed balance tests (p = 0.003) improved in the full cohort. Other than a greater confidence to carry out functional activities (Falls Efficacy Scale, p = 0.04), no carry-over effects were observed in functional and quality of life domains. Effects of intervention had reduced considerably at 6-week follow-up. Conclusions: Cueing training in the home has specific effects on gait, freezing and balance. The decline in effectiveness of intervention effects underscores the need for permanent cueing devices and follow-up treatment. Cueing training may be a useful therapeutic adjunct to the overall management of gait disturbance in Parkinson’s disease.

The attentional cost of external rhythmical cues and their impact on gait in Parkinson’s disease: effect of cue modality and task complexity

SummaryChanges in gait performance in 153 subjects with PD using three rhythmical cues (auditory, visual and somatosensory) were measured during a simple walking task and a dual walking task in the home. Subjects were ‘on’ medication and were cued at preferred step frequency. Accelerometers recorded gait and walking speed, step amplitude and step frequency were determined from raw data. Data were analysed with SAS using linear regression models. Gait performance during a single task reduced with cues in contrast to a dual task where PD subjects appeared to benefit from rhythmical cues (increased speed and step length). Effects were dependent on cue modality with significant improvements for auditory cues compared to others. A significant short-term carry-over effect of cues reduced 3 weeks later. Cues may reduce attentional demands by facilitating attentional allocation, accounting for differences of cue seen during single and dual task. Furthermore cue modality may influence attentional demand which is an important consideration for rehabilitation.

The effect of rhythmic somatosensory cueing on gait in patients with Parkinson's disease

BACKGROUND AND AIMS Gait and gait related activities in patients with Parkinsons disease (PD) can be improved with rhythmic auditory cueing (e.g. a metronome). In the context of a large European study, a portable prototype cueing device was developed to provide an alternative for rhythmic auditory cueing: rhythmic somatosensory cueing (RSC, a miniature vibrating cylinder attached to the wrist). We investigated whether PD patients could adapt their walking pattern using RSC under conditions of changing walking speed and the presence of potentially distracting visual flow while walking on a treadmill. METHODS A total of 17 patients with PD participated (mean age 63.4+/-10.3 years; Hoehn-Yahr score 2.5+/-0.9, mean Unified Parkinsons Disease Rating Scale score 49.8+/-13.7, mean disease duration 7.7+/-5.1 years). They performed systematic walking speed manipulations under 4 conditions in a random order: (1) no cue, no visual flow, (2) no cue, visual flow, (3) cue, no visual flow and (4) cue, visual flow. Visual flow in the form of a virtual corridor that moved at the current walking speed was projected on a 2 x 2 m rear-projection screen. The cueing rhythm was set at -10% of preferred stride frequency at each speed. Stride frequency was assessed using peaks in the trajectories of thigh sagittal plane segmental angles. RESULTS Walking with RSC resulted in lower stride frequencies, and thus larger step lengths (p-values <0.05), regardless of walking speed. The presence of visual flow did not impair the use of RSC, as evidenced by the lack of differences between conditions 3 and 4 (p>0.05). CONCLUSION Rhythmic somatosensory cueing may be a viable alternative for auditory cueing and is robust to changes in walking speed and visual distractors.

Walking speed during single and dual tasks in Parkinson's disease: which characteristics are important?

The impact of dual tasks on gait in Parkinsons disease (PD) reveals lack of automaticity and increased cognitive demands. We explored which characteristics explained walking speed with and without dual task interference and if they reflected the cognitive demands of the task. In 130 people with PD, gait performance was quantified in the home using accelerometers allowing estimates of single and dual task walking speed and interference (difference between dual and single task). Multiple regression analysis was used to explore the effect of 12 characteristics representing four domains (personal, motor symptoms, cognitive, affective) on gait outcomes. Thirty‐seven percent of variance in single task speed was explained by increased fear of falling, sex, age, disease severity, and depression; 34% of variance in dual task speed was explained by increased fear of falling, disease severity, medication, and depression; 12% of variance in interference scores was explained by greater disease severity and impaired executive function. Personal, motor, affective, and cognitive characteristics contribute to walking speed and interference, highlighting the multifactorial nature of gait. Different patterns of characteristics for each outcome indicates the impact of cognitive demand and task complexity, providing cautious support for dual task speed and interference as valid proxy measures of cognitive demand in PD gait.

Is impact of fatigue an independent factor associated with physical activity in patients with idiopathic Parkinson's disease?

To investigate the longitudinal association between fatigue and physical activity in Parkinsons disease (PD) and determine whether this association is distorted by potential confounders. Data from baseline, 3, 6, and 12 week assessments in a single blind randomized clinical trial with cross‐over design were used (N = 153). The Multidimensional Fatigue Inventory (MFI) was used to assess fatigue and an activity monitor to measure amount of physical activity (defined as % dynamic activity during each monitoring session). Time‐independent and time‐dependent factors were investigated for their possible univariate association with dynamic activity. Random coefficient analysis was applied. Candidate confounders were successively added to the longitudinal association model to determine if the association between dynamic activity and fatigue was distorted. A proportional change beyond 15% was considered to be significant. Fatigue was significantly associated with physical activity (β = −0.099, SE = 0.032, P = 0.002). This association was not significantly distorted by type of intervention, age, gender, social support, disease duration, disease severity, motor impairment, cognition, anxiety, or medication intake. Depression caused proportional change of 22.2% in the regression coefficient of MFI. After controlling for depression, a significant association between MFI and dynamic activity remained (β = −0.121, SE = 0.036, P = 0.000). The association found between fatigue and dynamic activity suggests that patients who experience higher levels of fatigue are less physically active. However, the total explained variance of dynamic activity by fatigue alone was small, suggesting that fatigue is only a minor factor in the complex of behavioral aspects that affect the amount of physical activity in patients with PD.

Everyday walking with Parkinson's disease: understanding personal challenges and strategies

Purpose. This qualitative study was designed to explore the personal experience of everyday walking with Parkinsons disease (PD), the challenges and the strategies employed to compensate for difficulties, to help contextualise the scientific knowledge base. Methods. Semi-structured interviews were undertaken with a sample of 20 people with idiopathic PD (12 male, 8 female; mean age 65 years (range 50 – 80); mean disease duration 10 years (range 2.5 – 26). Verbatim interview transcripts were analyzed thematically using NUD*IST N6 qualitative data analysis software. Results. Walking was invariably performed as an integral part of a purposeful activity within a specific context, termed walking ‘plus’, with challenges encountered by people with PD in three main areas: Undertaking tasks; negotiating environments; and making transitions to walking. The two key strategies to compensate for difficulties experienced were monitoring through the use of concentration, and correcting through generating rhythm and size of steps. Carers supported monitoring and correcting. Conclusion. People with PD need to constantly assess and drive their walking performance. Attentional resources, which can themselves be compromised in PD, were used to accomplish what is normally a largely automatic activity. Personal accounts support scientific hypotheses. Rehabilitation interventions and measurements in PD need to reflect both the physical and psychosocial context of everyday walking.

Gait and gait-related activities and fatigue in Parkinson's disease: What is the relationship?

Purpose. To explore the relationship between gait and gait-related activities and fatigue in Parkinsons disease (PD). Method. Twenty people with idiopathic PD (12 male, 8 female; mean age 64.6 ± 7.96) and 10 age, sex and education matched controls (6 male, 4 female; mean age 63.5 ± 7.03) wore an activity monitor for approximately 24 h, from which the percentage time walking and standing, the number of periods of walking greater than 10 sec were derived. Prior to monitoring, levels of fatigue (Multi-dimensional Fatigue Index, MFI) were evaluated. Results. Activity data related to gait were compared for the waking hours of the day, reflected by the period between 6 am and 10 pm. Overall, PD subjects demonstrated reduced activity compared to controls, however there was no significant difference between PD and controls for the percentage time spent walking (p = 0.149), standing (p = 1.0) or engaged in periods of walking that were greater than 10 sec (p = 0.059). Significantly greater levels of fatigue were experienced by PD subjects in all MFI domains compared to controls (physical p = 0.001; activity p = 0.001; general p = 0.001; mental p = 0.028; motivation p = 0.024). There was no clear association between activity and fatigue in PD subjects. Conclusions. Evidence of increased fatigue is not supported by evidence of significantly decreased levels of activity in PD subjects. The relationship between activity and fatigue therefore remains unclear, highlighting the complex nature of the relationship between these factors. Further work is required to increase our understanding of the impact of fatigue on gait and gait-related activity so that improved management can be explored.