Effects of Brain Pathologies on Spatiotemporal Gait Parameters in Patients with Mild Cognitive Impairment.

BACKGROUND: Impaired gait can precede dementia. The associations between gait parameters and brain pathologies are therefore of interest. OBJECTIVE: To explore how different brain pathologies (i.e., vascular and Alzheimer's) are associated with specific gait parameters from various gait components in persons with mild cognitive impairment (MCI), who have an increased risk of developing dementia. METHODS: This cross-sectional study included 96 patients with MCI (mean 72, ±7.5 years; 52% women). Gait was evaluated by using an electronic walkway, GAITRite®. Four gait parameters (step velocity variability; step length; step time; stance time asymmetry) were used as dependent variables in multivariable linear regression analyses. Independent variables included Alzheimer's disease pathologies (amyloid-ß and tau) by using PET imaging and white matter hyperintensities (WMH) by using MRI. Covariates included age, sex, comorbidities (and intracranial volume in analyses that includedWMH). RESULTS: Increased tau-PET (Braak I-IV region of interest [ROI]) was associated with step velocity variability (standardized regression coefficient, ß= 0.383, p < 0.001) and step length (ß= 0.336, p < 0.001), which remained significant when using different Braak ROIs (I-II, III-IV, V-VI). The associations remained significant when adjusting for WMH (p < 0.001). When also controlling for gait speed, tau was no longer significantly (p = 0.168) associated with an increased step length. No significant associations between gait and Aß-PET load or WMH were identified. CONCLUSIONS: The results indicate that one should pay specific attention to assess step velocity variability when targeting single task gait in patients with MCI. Future studies should address additional gait variability measures and dual tasking in larger cohorts.

Components of gait in people with and without mild cognitive impairment.

BACKGROUND: Several objective gait parameters are associated with cognitive impairment, but there is limited knowledge of gait models in people with mild cognitive impairment (MCI). RESEARCH QUESTION: How can 18 objective gait characteristics be used to define different components of gait in people with MCI (with suspected incipient neurocognitive disorder) and cognitively unimpaired people (CU), respectively? METHODS: Spatiotemporal gait data were collected by using an electronic walkway (GAITRite®), i.e. assessments in comfortable gait speed. Using cross-sectional gait data, two principal component analyses (PCA) were performed (varimax rotation) to define different components of gait in people with MCI (n = 114) and CU (n = 219), respectively, from the BioFINDER-2 study. RESULTS: Both PCAs produced four components, here called Variability, Pace/Stability, Rhythm and Asymmetry. Total variance explained was 81.0% (MCI) versus 80.3% (CU). The Variability component explained the largest amount of variance (about 25%) in both groups. The highest loading gait parameter was the same for both groups in three out of four components, i.e. step velocity variability (Variability), mean step length (Pace/Stability) and mean step time (Rhythm). In the asymmetry component, stance time asymmetry (MCI) and swing time asymmetry (CU) loaded the highest. SIGNIFICANCE: The gait components seem similar in people with and without MCI, although there were some differences. This study may aid the identification of gait variables that represent different components of gait. Gait parameters such as step velocity variability, mean step length, mean step time as well as swing and stance time asymmetry could serve as interesting core variables of different gait components in future research in people with MCI (with suspected incipient neurocognitive disorder) and CU. However, the selection of gait variables depends on the purpose. It needs to be noted that assessment of variability measures requires more advanced technology than is usually used in the clinic.

Work conditions, support, and changing personal priorities are perceived important for return to work and for stay at work after stroke - a qualitative study.

PURPOSE: To explore work related and personal facilitators and barriers for return to work (RTW) and stay at work after stroke. MATERIALS AND METHODS: Twenty individuals post-stroke (median age 52 years; seven women) were interviewed in focus groups. Data were analyzed by using qualitative content analysis. RESULTS: An overall theme "Work conditions, support and changed personal priorities influenced RTW and stay at work after stroke" emerged and covered three categories: "Adjustments and flexibility at the work place facilitated RTW and a sustainable work situation", "Psychosocial support and knowledge about stroke consequences facilitated work and reduced stress", and "Changed view of work and other personal priorities". Physical adjustments at the work place and flexibility in the work schedule were perceived facilitators. Support from family and colleagues were important, whereas lack of knowledge of stroke disabilities at the work place was perceived a barrier. Also changed personal priorities in relation to the work and the current life situation influenced RTW in various ways. CONCLUSIONS: The individual's opportunities to influence the work situation is a key factor for RTW and the ability to stay at work after stroke. Adjustments, flexibility, support, knowledge of stroke, and receptivity to a changed view of work are important for a sustainable work situation.Implications for rehabilitationPhysical adjustments at the work place, a flexible work schedule and support increase the individual's possibility to RTW and maintain a sustainable work situation after stroke.Changed work and life priorities after a stroke need attention in the RTW process.Rehabilitation professionals have an important role in providing knowledge about the disabilities following stroke, and how they impact work ability. Individually tailored recommendations for work place adjustments which enable RTW and a sustainable work situation are warranted.

Perceived walking difficulties in Parkinson's disease - predictors and changes over time.

BACKGROUND: People with Parkinson's disease (PD) have described their walking difficulties as linked to activity avoidance, social isolation, reduced independence and quality of life. There is a knowledge gap regarding predictive factors of perceived walking difficulties in people with PD. Such knowledge could be useful when designing intervention studies. This study aimed to investigate how perceived walking difficulties evolve over a 3-year period in people with PD. A specific aim was to identify predictive factors of perceived walking difficulties. METHODS: One hundred forty-eight people with PD (mean age 67.9 years) completed the Generic Walk-12 (Walk-12G) questionnaire (which assesses perceived walking difficulties) at both baseline and the 3-year follow-up. Paired samples t-test was used for comparing baseline and follow-up mean scores. Multivariable linear regression analyses were used to identify predictive factors of perceived walking difficulties. RESULTS: Perceived walking difficulties increased after 3 years: mean Walk-12G score 14.8 versus 18.7, p < 0.001. Concerns about falling was the strongest predictor (ß = 0.445) of perceived walking difficulties, followed by perceived balance problems while dual tasking (ß = 0.268) and pain (ß = 0.153). Perceived balance problems while dual tasking was the strongest predictor (ß = 0.180) of a change in perceived walking difficulties, followed by global cognitive functioning (ß = - 0.107). CONCLUSIONS: Perceived walking difficulties increase over time in people with PD. Both personal factors (i.e. concerns about falling) and motor aspects (i.e. balance problems while dual tasking) seem to have a predictive role. Importantly, our study indicates that also non-motor symptoms (e.g. pain and cognitive functioning) seem to be of importance for future perceived walking difficulties. Future intervention studies that address these factors need to confirm their preventative effect on perceived walking difficulties.

Prediction of Life Satisfaction in People with Parkinson's Disease.

INTRODUCTION: People with Parkinson's disease (PD) have lower life satisfaction (LS) than healthy peers. No study has yet identified predictors of LS in people with PD. Such information would be valuable for health care and future interventions that aim to maintain or increase LS. AIM: To examine how LS evolved in people with PD over a 3-year period, as well as to identify predictive factors of LS. METHODS: We used data from baseline assessments and a 3-year follow-up of 163 people with PD (baseline, mean age 68 years; median PD duration 8 years, 35% women). LS was assessed with item 1 of the Life Satisfaction Questionnaire (LiSat-11). Dichotomized LS data from the 3-year follow-up were used as the dependent variable in multivariable logistic regression analyses. In the first step, independent variables included baseline information on sex, education, general self-efficacy, motor symptoms, perceived walking difficulties, fall-related activity avoidance, and difficulties with/need help in activities of daily living. At the second step, depressive symptoms were added as an independent variable. RESULTS: The proportion of those who reported being satisfied with their lives reduced from 63.2% at baseline to 49.7% 3 years later (p=0.003). When depressive symptoms were not included in the analysis, general self-efficacy (odds ratio, OR = 1.081; 95% CI = 1.019-1.147) and perceived walking difficulties (OR = 0.962; 95% CI = 0.929-0.997) were significant (p < 0.05) predictors of LS 3 years later. With depressive symptoms included, the influence of walking difficulties diminished, and depressive symptoms (OR = 0.730; 95% CI = 0.607-0.877) and general self-efficacy (OR = 1.074; 95% CI = 1.010-1.142) were the only significant predictors of LS 3 years later. CONCLUSIONS: LS is reduced over a 3-year period. The study suggests that perceived walking difficulties, general self-efficacy, and depressive symptoms are important predictors of LS in people with PD.

Predictive Factors of Fall-Related Activity Avoidance in People With Parkinson Disease-A Longitudinal Study With a 3-Year Follow-up.

BACKGROUND AND PURPOSE: Knowledge of predictive factors can foster the development of preventive approaches. This study examined how prevalence and severity of fall-related activity avoidance evolve over a 3-year period in people with Parkinson disease (PD). A specific aim was to identify predictive factors of fall-related activity avoidance (ie, modified Survey of Activities and Fear of Falling in the Elderly [mSAFFE] scores) after 3 years. METHODS: The sample included 151 people with PD (mean [SD] age: 68 [8.8] years). The mSAFFE score was the dependent variable in multivariable linear regression analyses, with 17 potential predictors. On the basis of a collinearity check, 2 models studying various risk factors were developed. Model 1 included concerns about falling and model 2 walking difficulties. RESULTS: After 3 years, more participants reported fall-related activity avoidance, that is, 34% versus 50% (P < 0.001). Regression model 1 explained 63% of the variance. The strongest predictive factor was concerns about falling (standardized regression coefficient, ß = 0.589), followed by pain (ß = 0.161), unsteadiness while turning (ß = 0.137), and age (ß = 0.136). These variables remained significant when adjusting for mSAFFE baseline scores.In model 2 (explained 50% of the variance), the strongest predictive factor was perceived walking difficulties (ß = 0.392), followed by age (ß = 0.238), unsteadiness while turning (ß = 0.198), and pain (ß = 0.184). Unlike the other factors, walking difficulties were not significant when adjusting for mSAFFE baseline scores. DISCUSSION AND CONCLUSIONS: Fall-related activity avoidance increased over time in people with PD. If fall-related activity avoidance is to be targeted, this study suggests that interventions should address concerns about falling, pain, unsteadiness while turning, and walking difficulties.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A310).

Predictive Factors of Concerns about Falling in People with Parkinson's Disease: A 3-Year Longitudinal Study.

INTRODUCTION: Fear of falling (FOF) is more common in people with Parkinson's disease (PD) than in healthy controls. It can lead to several negative consequences such as restrictions in everyday life. Moreover, FOF is a risk factor for future falls. AIM: This study aimed to identify predictive factors of FOF (conceptualized as concerns about falling) after three years, with and without adjusting for concerns about falling at baseline, in people with PD. METHODS: This study included 151 participants (35% women) with PD. At baseline, their mean (SD) age and PD duration were 68 (±9.0) and 9 (±6.1) years, respectively. The Falls Efficacy Scale-International (FES-I) was used as the dependent variable in multivariable linear regression analyses. RESULTS: The mean (SD) FES-I score increased from 28.1 (11.9) to 33.1 (14.0) three years later (p < 0.001). The strongest (according to the standardized regression coefficient, ß) predictor of concerns about falling was walking difficulties (ß = 0.378), followed by age (0.227), problems maintaining balance while dual tasking (0.172), and needing help in daily activities (0.171). When adjusting for baseline FES-I scores, the strongest predictive factor was problems maintaining balance while dual tasking (ß = 0.161), which was followed by age (0.131) and female sex (0.105). CONCLUSIONS: This study pinpoints several predictive factors of concerns about falling that are modifiable and which could be addressed in rehabilitation: perceived walking difficulties, having problems maintaining balance while dual tasking, and dependence on others in daily activities. The importance of dual tasking is a novel finding, which future studies need to confirm or refute. One should be aware of the fact that an increased age predicts concerns about falling with and without adjusting for baseline FES-I scores, whereas female sex predicts concerns about falling only when adjusting for baseline FES-I scores.

Psychometric Properties of Three Fatigue Rating Scales in Individuals With Late Effects of Polio.

OBJECTIVE: To evaluate the psychometric properties of the Fatigue Severity Scale (FSS), the Fatigue Impact Scale (FIS), and the Multidimensional Fatigue Inventory (MFI-20) in persons with late effects of polio (LEoP). More specifically, we explored the data completeness, scaling assumptions, targeting, reliability, and convergent validity. METHODS: A postal survey including FSS, FIS, and MFI-20 was administered to 77 persons with LEoP. Responders received a second survey after 3 weeks to enable test-retest reliability analyses. RESULTS: Sixty-one persons (mean age, 68 years; 54% women) responded to the survey (response rate 79%). Data quality of the rating scales was high (with 0%-0.5% missing item responses), the corrected item-total correlations exceeded 0.4 and the scales showed very little floor or ceiling effects (0%-6.6%). All scales had an acceptable reliability (Cronbach's  ≥0.95) and test-retest reliability (intraclass correlation coefficient, ≥0.80). The standard error of measurement and the smallest detectable difference were 7%-10% and 20%-28% of the possible scoring range. All three scales were highly correlated (Spearman's correlation coefficient rs=0.79-0.80; p<0.001). CONCLUSION: The FSS, FIS, and MFI-20 exhibit sound psychometric properties in terms of data completeness, scaling assumptions, targeting, reliability, and convergent validity, suggesting that these three rating scales can be used to assess fatigue in persons with LEoP. As FSS has fewer items and therefore is less time consuming it may be the preferred scale. However, the choice of scale depends on the research question and the study design.

Experiences of fear of falling in persons with Parkinson's disease - a qualitative study.

BACKGROUND: Fear of falling is common among persons with Parkinson's disease and is negatively associated with quality of life. However a lack of in-depth understanding of fear of falling as a phenomenon persists. This qualitative study aimed to explore the experiences of fear of falling in persons with Parkinson's disease. METHODS: Individual interviews were performed with twelve persons with Parkinson's disease (median age 70 years, median Parkinson duration 9 years, 50% women). The interviews were semi-structured and followed a study-specific interview guide. The transcribed interviews were analyzed using qualitative content analysis. RESULTS: Fear of falling was experienced as a disturbing factor in everyday life. It generated a feeling of vulnerability and made daily activities and everyday environments seem potentially hazardous. Persons also missed performing previous activities. The fear of falling was a varying experience, fueled by an awareness of falls and near falls, Parkinson-related symptoms and disabilities, and by others in their environment. The persons adopted different strategies to handle their fear of falling. Activities were adapted, avoided, performed with help, or carried out despite their fear of falling. CONCLUSIONS: The experiences of fear of falling were complex, multifaceted and varied over time and in relation to different activities and environments. This indicates that interventions targeting fear of falling need to be individually tailored for persons with Parkinson's disease and should focus on several aspects, such as Parkinson-related symptoms and disabilities, activities and environmental factors. This study provides new information that increases the understanding of fear of falling, which has implications for researchers as well as clinicians working with persons with Parkinson's disease and fear of falling.

Psychometric Evaluation of the Parkinson's Disease Activities of Daily Living Scale.

OBJECTIVE: To evaluate a set of psychometric properties (i.e., data completeness, targeting, and external construct validity) of the Parkinson's disease Activities of Daily Living Scale (PADLS) in people with Parkinson's disease (PD). Specific attention was paid to the association between PADLS and PD severity, according to the Hoehn & Yahr (H&Y) staging. METHODS: The sample included 251 persons with PD (mean age 70 [SD 9] years). Data collection comprised a self-administered postal survey, structured interviews, and clinical assessments at home visits. RESULTS: Data completeness was 99.6% and the mean PADLS score was 2.1. Floor and ceiling effects were 22% and 2%, respectively. PADLS scores were more strongly associated (rs > 0.5) with perceived functional independence, ADL dependency, walking difficulties, and self-rated PD severity than with variables such as PD duration and cognitive function (rs < 0.5). PADLS scores differed across H&Y stages (Kruskal-Wallis test, p < 0.001). Those in H&Y stages IV-V had more ADL disability than those in stage III (Mann-Whitney U test, p < 0.001), whereas there were no significant differences between the other stages. CONCLUSION: PADLS revealed excellent data completeness, acceptable targeting, and external construct validity. It seems to be well suited as a rough estimate of ADL disability in people with PD.

Psychometric properties of the original and short versions of the Falls Efficacy Scale-International (FES-I) in people with Parkinson's disease.

BACKGROUND: Fear of falling is common in people with Parkinson's disease (PD) and is associated with an increased risk for future falls, activity limitations and a reduced quality of life. The Falls Efficacy Scale-International (FES-I) assesses fear of falling conceptualized as concerns about falling. The original FES-I has good psychometric properties in people with PD, but whether this applies also for the short version of FES-I remains to be shown. The aim of the present study was to evaluate the psychometric properties of the short FES-I and to compare these with the original FES-I in the same sample of people with PD. The investigated psychometric properties included known groups validity, data completeness, scaling assumptions, targeting and reliability. METHODS: A postal survey, which included the original, full-length FES-I, was distributed to 174 people with PD. Responders received a second survey after two weeks. From these data, short FES-I total scores were calculated by extracting the items that are included in the short version of the scale. RESULTS: Median age and PD duration of the 101 responders (43% women) were 73 and 5 years, respectively. The original as well as the short FES-I scores were able to discriminate (p < 0.001) between groups with and without fear of falling, activity avoidance, falls, near falls, and with various self-rated PD severity, respectively. Both versions of FES-I had a high level of data completeness (0.7 to 0.9% missing item responses). Scaling assumptions were acceptable for the original as well as the short FES-I. While the short FES-I had 19% floor effect, the original version was better targeted. Both versions were reliable and obtained high values for internal consistency (Cronbach's alpha >0.8) and test-retest reliability (Intraclass Correlation Coefficient > 0.9). CONCLUSIONS: Both the original and short FES-I revealed generally good psychometric properties in people with PD, although the original scale was better targeted. Due to the higher floor effect in the short FES-I, the present findings favors using the original, full-length FES-I in longitudinal follow-ups, intervention studies and clinical practice when addressing concerns about falling.

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.

Psychometric properties of four fear of falling rating scales in people with Parkinson's disease.

BACKGROUND: Fear of falling (FOF) is commonly experienced in people with Parkinson's disease (PD). It is a predictor of recurrent falls, a barrier to physical exercise, and negatively associated with health-related quality of life. A variety of rating scales exist that assess different aspects of FOF but comprehensive head-to-head comparisons of their psychometric properties in people with PD are lacking. The aim of this study was to evaluate the psychometric properties of four FOF rating scales in people with PD. More specifically, we investigated and compared the scales' data completeness, scaling assumptions, targeting, and reliability. METHODS: The FOF rating scales were: the Falls Efficacy Scale-International (FES-I), the Swedish FES (FES(S)), the Activities-specific Balance Confidence scale (ABC), and the modified Survey of Activities and Fear of Falling in the Elderly (mSAFFE). A postal survey was administered to 174 persons with PD. Responders received a second survey after two weeks. RESULTS: The mean (SD) age and PD duration of the 102 responders were 73 (8) and 7 (6) years, respectively. ABC had worse data completeness than the other scales (6.9 vs. 0.9-1.3% missing data). All scales had corrected item-total correlations exceeding 0.4 and showed acceptable reliabilities (Cronbach's alpha and Intraclass Correlation Coefficient (ICC) >0.80) but only FES-I had ICC >0.90. The standard error of measurements ranged from 7% (FES-I) to 12% (FES(S)), and the smallest detectable differences ranged from 20% (FES-I) to 33% (FES(S)) of the total score ranges. ABC and FES(S) had substantially more outliers than mSAFFE and FES-I (10 and 15 vs. 3 and 4, respectively) when the two test occasions were compared. CONCLUSIONS: When assessing FOF in people with PD, the findings in the present study favoured the choice of FES-I or mSAFFE. However, FES-I was the only scale with ICC >0.90 which has been suggested as a minimum when using a scale for individual comparisons.