Translation, cultural adaptation and validation of the Arabic version of the king's Parkinson's disease pain scale.

PURPOSE: Pain in Parkinson's disease (PD) is a highly prevalent non-motor symptom occurring in this population. The King's PD Pain Scale (KPPS) was developed to assess pain in people with PD. This study aimed to provide a cross-cultural adaptation and translation of the KPPS into the Arabic language (A-KPPS), and to investigate the construct and convergent validity, internal consistency, and reliability of the translated scale. MATERIALS AND METHODS: The English KPPS was translated into Arabic and back-translated into English by an independent translation team. The Arabic version was tested in 103 native Arabic speaking PD patients. We assessed construct validity, convergent validity, and test-retest reliability of the A-KPPS using factor analysis method, comparison with other valid and reliable measures, and using intra-class correlations, respectively. RESULTS: The A-KPPS had three main factors "somatic pain", "visceral and burning pain" and "orofacial pain", rather than the original four factors scale. The A-KPPS correlated with measures of disease motor severity, depression, anxiety, quality of life and pain (p < 0.05). Furthermore, the A-KPPS total score had high test-retest reliability (ICC = 0.9). CONCLUSIONS: The A-KPPS demonstrated moderate to good validity and reliability. The A-KPPS can facilitate the assessment and treatment of pain in Arabic-speaking people with PD worldwide.

Pain is a highly prevalent non-motor symptom of Parkinson's disease (PD) that is often overlooked.The King's PD Pain Scale (KPPS) is specially designed to assess pain localization, intensity, and frequency in people with PD.The Arabic translation of the KPPS is a valid and reliable tool for the assessment of pain in Arabic speaking people with PD.

Age-related differences in lower limb muscle activation patterns and balance control strategies while walking over a compliant surface.

Substantial evidence demonstrates that falls in older adults are leading causes of fatal and non-fatal injuries and lead to negative impacts on the quality of life in the aging population. Most falls in older fallers result from unrecoverable limb collapse during falling momentum control in the single limb support (SLS) phase. To understand why older adults are more likely to fall than younger adults, we investigated age-related differences in knee extensor eccentric control, lower limb muscle activation patterns, and their relation to balance control. Ten older and ten younger healthy adults were compared during balance control while walking on a compliant surface. There was a positive correlation between knee extensor eccentric work in the perturbed leg and the swinging leg's speed and margin of stability. In comparison to younger adults, older adults demonstrated (1) less eccentric work, reduced eccentric electromyography burst duration in the perturbed leg, (2) higher postural sway during SLS, and (3) impaired swinging leg balance control. The group-specific muscle synergy showed that older adults had a prominent ankle muscle activation, while younger adults exhibited a more prominent hip muscle activation. These findings provide insight into targeted balance rehabilitation directions to improve postural stability and reduce falls in older adults.

Cognitive status and sleep quality can explain the fear of falling and fall history in people with Parkinson's disease.

Fear of falling (FOF) is highly prevalent in people with Parkinson's disease (PwPD) and contributes to high fall risk. Studies reporting on the relationship between falls, FOF, and non-motor factors such as cognitive function and sleep quality in Parkinson's disease are limited. This study aimed to investigate (1) the relationship of cognitive function and sleep quality with FOF, and history of falls in PwPD; (2) differences in cognitive function and sleep quality between Parkinson's disease fallers and non-fallers; and (3) a cut-off score for cognitive function and sleep quality to discriminate Parkinson's disease fallers from non-fallers. Fifty PwPD were assessed for FOF [Falls Efficacy Scale-International (FES-I)], cognition [Montréal Cognitive Assessment (MOCA)], sleep quality [Pittsburgh Sleep Quality Index (PSQI)], and falls history. The MOCA is significantly associated with FES-I scores ( R2  = 0.429, P  < 0.0001). Both MOCA ( P  = 0.012) and PSQI ( P  = 0.027) were associated with falls history even after adjusting for confounding factors (age, sex, L-dopa use, Parkinson's disease severity). Both MOCA and PSQI scores were able to distinguish fallers from non-fallers with cut-off scores of 15.5 and 7.5, respectively. Although our findings revealed that both cognitive function and sleep quality are important factors influencing falls and FOF in PwPD, it remains to be determined if addressing cognitive impairments and poor sleep quality may favorably impact balance before integrating such screenings into fall prevention programs.

Age-related differences in stepping stability following a sudden gait perturbation are associated with lower limb eccentric control of the perturbed limb.

INTRODUCTION: Falls are a leading cause of severe injuries and a major threat to quality of life in older adults. Elderly fallers demonstrate insufficient eccentric quadriceps control during the weight acceptance phase of initial single limb stance. However, the functional role of eccentric control of the perturbed (leading) leg during walking balance recovery and its age-related differences have not yet been studied; thus we investigated age-related differences in eccentric control at the knee of the perturbed leg and its influence on the postural sway and stability of the trailing leg during balance recovery following unexpected surface drop perturbations. METHODS: Ten younger and ten older healthy adults were compared during balance recovery following an 8 cm unexpected surface drop perturbation at gait initiation. Outcomes related to perturbed leg included 1) eccentric knee extensor work; 2) electromyography (EMG) peak amplitude, peak latency, and eccentric EMG burst duration of the rectus femoris (RF); and 3) knee flexion angle during the single limb support. Outcomes related to stability of the trailing leg included 4) margin of stability (MoS) at first compensatory step touchdown after the perturbation. 5) Postural sway (standard deviation of center of mass acceleration) was measured in the anterior-posterior (A-P), medio-lateral (M-L), vertical directions during the single limb support. RESULTS: Compared to younger adults, older adults demonstrated lower eccentric knee extensor work (p = 0.034), shorter RF EMG burst duration (p < 0.01), delayed RF EMG peak latency (p = 0.01), smaller knee flexion angle (p = 0.01) and MoS (p = 0.04), and higher postural sway (M-L (p = 0.02), vertical (p < 0.01)). There was a positive correlation between eccentric work and MoS (p = 0.03) and a negative correlation between M-L postural sway and 1) RF eccentric EMG burst duration (p = 0.04), and 2) eccentric work (p = 0.01). CONCLUSIONS: Older adults demonstrated deficits in eccentric knee extensor control in the perturbed leg during single limb support, which contributed to reduced stability of the trailing leg compensatory step and greater postural sway during balance recovery. This finding provides insight into mechanisms of fall recovery from an unexpected unilateral postural perturbation and directions for lower limb strengthening exercises for aging populations.

Understanding the influence of pain and fatigue on physical performance, fear of falling and falls in people with Parkinson's disease: a pilot study.

Objective: Pain and fatigue are highly prevalent debilitating symptoms in Parkinson's disease (PD), however, their relationship with physical performance, fear of falling (FOF) and falls is not clear. We aim in this pilot study to investigate the relationship of pain and fatigue with physical performance, FOF and falls in people with Parkinson's disease (PwPD). Materials & methods: 53 PD patients were assessed for fall history, physical performance, FOF, pain and fatigue. Results: Pain and fatigue are significantly associated with physical performance and FOF (p ≤ 0.002). Pain and fatigue were different between fallers and non-fallers (p < 0.5), but only fatigue could distinguish fallers from non-fallers (area under the receiver operating characteristics curve = 0.81; p < 0.0001). Conclusion: This pilot study indicated that FOF in PwPD is significantly associated with pain and fatigue. Furthermore, fatigue level is related to fall history. By addressing pain and fatigue, we may ameliorate the deterioration of FOF and falls in PwPD.

Real-time assessment of daytime sleepiness in drivers with multiple sclerosis.

BACKGROUND: Daytime sleepiness is a common symptom of multiple sclerosis (MS) that may jeopardize safe driving. Our aim was to compare daytime sleepiness, recorded in real-time through eyelid tracking, in a simulated drive between individuals with MS (iwMS) and healthy controls. METHODS: Fifteen iwMS (age = median (Q1 - Q3), 55 (50 - 55); EDSS = 2.5 (2 - 3.5); 12 (80%) female) were matched for age, sex, education, and cognitive status with 15 controls. Participants completed self-reported fatigue and sleepiness scales including the Modified Fatigue Impact Scale (MFIS), Pittsburg Sleep Quality Inventory (PSQI), and Epworth Sleepiness Scale (ESS). Percentage of eyelid closure (PERCLOS) was extracted from a remote eye tracker while completing a simulated drive of 25 min. RESULTS: Although iwMS reported more symptoms of fatigue (MFIS, p = 0.003) and poorer sleep quality (PSQI, p = 0.008), they did not report more daytime sleepiness (ESS, p = 0.45). Likewise, there were no differences between groups in real-time daytime sleepiness, indexed by PERCLOS (p = 0.82). Both groups exhibited more real-time daytime sleepiness as they progressed through the drive (time effect, p < 0.0001). The interaction effect of group*time (p = 0.05) demonstrated increased symptoms of daytime sleepiness towards the end of the drive in iwMS compared to controls. PERCLOS correlated strongly (Spearman ρ = 0.76, p = 0.001) with distance out of lane in iwMS. CONCLUSION: IwMS show exacerbated symptoms of daytime sleepiness during a monotonous, simulate drive. Future studies should investigate the effect of MS on daytime sleepiness during real-world driving.

Examining the influence of mental stress on balance perturbation responses in older adults.

BACKGROUND: Reach-to-grasp responses following balance perturbations are important to fall prevention but are often ineffective in older adults. The ability to shift attention from an ongoing cognitive task to balance related processes has been shown to influence reach-to-grasp effectiveness in older adults. However, the added influence of stress and anxiety - known to negatively affect attention shifting ability - has not yet been explored in relation to recovery from balance perturbations. Given that fear and anxiety over falling is a key fall risk factor, an understanding of how such a negative mental state may affect postural reactions is important. This study aimed to investigate the effect of varied induced emotional states on reach-to-grasp balance responses in older adults. METHODS: Healthy older adults (mean age 70.5 ± 5.38 years) stood laterally between 2 handrails with contact sensors. A safety harness with an integrated loadcell was worn to prevent falls and measure the amount of harness assistance (expressed as percent body weight). With instructions to grasp one rail to restore balance, participants' balance was laterally disturbed using surface translations under three randomized conditions: no cognitive task, neutral (verb generation) task, and mental stress task with negative prompts (paced auditory serial addition). The primary outcome was frequency of protective grasps. Secondary outcomes included frequency of harness assistance during trials with grasp errors as well as wrist movement time, trajectory distance, and peak velocity. RESULTS: Perceived level of distress was highest for the mental stress task compared to no task (p < 0.001) and neutral task conditions (p = 0.008). The mental stress task resulted in the lowest percentage of protective grasps (p < 0.001) in response to balance perturbations. Closer examination of trials that resulted in grasp errors (i.e., collisions or overshoots), revealed increased harness assistance and reduced peak velocity of wrist movement (p < 0.001) under the mental stress condition compared to grasp errors that occurred under the no task or neutral task condition. DISCUSSION AND CONCLUSION: Distressing mental thoughts immediately prior to a balance perturbation lead to reduced effectiveness in reach-to-grasp balance responses compared to no or neutral cognitive tasks and should be considered as a possible fall risk factor.

Age-Related Differences in Arm and Trunk Responses to First and Repeated Exposure to Laterally Induced Imbalances.

The objective of this study was to examine age-related differences in arm and trunk responses during first and repeated step induced balance perturbations. Young and older adults received 10 trials of unpredictable lateral platform translations. Outcomes included maximum arm and trunk displacement within 1 s of perturbation and at first foot lift off (FFLO), arm and neck muscle activity as recorded using electromyography (EMG), initial step type, balance confidence, and percentage of harness-assisted trials. Compared to young adults, older adults demonstrated greater arm and trunk angular displacements during the first trial, which were present at FFLO and negatively associated with balance confidence. Unlike young adults, recovery steps in older adults were directed towards the fall with a narrowed base of support. Over repeated trials, rapid habituation of first-trial responses of bilateral arm and trunk displacement and EMG amplitude was demonstrated in young adults, but was absent or limited in older adults. Older adults also relied more on harness assistance during balance recovery. Exaggerated arm and trunk responses to sudden lateral balance perturbations in older adults appear to influence step type and balance recovery. Associations of these persistently amplified movements with an increased reliance on harness assistance suggest that training to reduce these deficits could have positive effects in older adults with and without neurological disorders.

A systematic review of upper extremity responses during reactive balance perturbations in aging.

BACKGROUND: Balance responses to perturbations often involve the arms in an attempt to either restore balance or protect against impact. Although a majority of research has been dedicated to understanding age-related changes in lower limb balance responses, there is a growing body of evidence supporting age-related changes in arm responses. This systematic review aimed to summarize differences in arm responses between older and younger adults under conditions requiring counterbalancing, reaching to grasping, and protection against impact. METHODS: Following a systematic review and critical appraisal of the literature, data regarding the arm response in studies comparing young and older adults was extracted. The resulting articles were also assessed for quality to determine risk of bias. RESULTS: Fifteen high quality studies were identified. The majority of these studies reported delayed onsets in muscle activation, differences in arm movement strategies, delayed movement timing, increased impact forces, and greater grasp errors in older compared to young adults. These differences were also identified under varied visual and cognitive conditions. CONCLUSIONS: The studies included in this review demonstrate age-related differences in arm responses regardless of the direction and nature of the perturbation. These differences could provide insight into developing more targeted rehabilitation and fall prevention strategies. More research is needed to assess whether the identified age-related differences are a necessary compensation or a contributory factor to balance impairments and fall risk in older adults.

Cognitive performance and cognitive workload in multiple sclerosis: Two different constructs of cognitive functioning?

BACKGROUND: Cognitive impairment in individuals with Multiple Sclerosis (iwMS) is traditionally diagnosed using performance measures on cognitive tests. Yet, performance on cognitive tests does not convey the amount of mental effort or cognitive workload it takes to complete the task. The main aim was to evaluate whether cognitive performance and cognitive workload are two different constructs of cognitive functioning in iwMS. METHODS: IwMS were categorized into cognitive impairments (iwMS+, n = 10) and no cognitive impairments (iwMS-, n = 12) using their performance on Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS). Their scores on BICAMS, Stroop, and trail making tests were compared to age- and education-matched controls (n = 22). Cognitive workload was assessed using the self-reported NASA Task Load Index and the Index of Cognitive Activity, derived from pupillary response. RESULTS: IwMS+ performed worse on most cognitive tests compared to iwMS- and controls. However, iwMS+ did not report or exhibit greater cognitive workload compared to the other groups. Potential confounding variables, such as sex, use of antidepressants, and symptoms of depression, fatigue, and dysautonomia did not influence the lack of correlation between cognitive performance and cognitive workload in all three groups. CONCLUSION: Cognitive performance and cognitive workload seem to measure different cognitive constructs of cognitive functioning in MS. Our results suggest that iwMS+ do not show effective allocation of cognitive resources to compensate for deteriorated performance in cognitive tests.

Pilot Feasibility Study Examining Pupillary Response During Driving Simulation as a Measure of Cognitive Load in Breast Cancer Survivors.

OBJECTIVES: To test the feasibility of adding driving simulation tasks to measure visuospatial ability and processing speed to an existing neurocognitive battery for breast cancer survivors (BCSs). SAMPLE & SETTING: 38 BCSs and 17 healthy controls from a cross-sectional pilot study conducted at the University of Kansas Medical Center. METHODS & VARIABLES: Exploratory substudy measuring pupillary response, visuospatial ability, and processing speed during two 10-minute driving simulations (with or without n-back testing) in a sample of BCSs with self-reported cognitive complaints and healthy controls. RESULTS: Feasibility of measurement of pupillary response during driving simulation was demonstrated. No between-group differences were noted for pupillary response during driving simulation. BCSs had greater visuospatial ability and processing speed performance difficulties than healthy controls during driving simulation without n-back testing and slower n-back response time. IMPLICATIONS FOR NURSING: Preliminary evidence showed a possible link between cancer/treatment on visuospatial ability and processing speed in BCSs.