Test-retest reliability of physical activity questionnaires in Parkinson's disease.

BACKGROUND: People with Parkinson's disease are less physically active than controls. It is important to promote physical activity, which can be assessed using different methods. Subjective measures include physical activity questionnaires, which are easy and cheap to administer in clinical practice. Knowledge of the psychometric properties of physical activity questionnaires for people with Parkinson's disease is limited. The aim of this study was to evaluate the test-retest reliability of physical activity questionnaires in individuals with Parkinson's disease without cognitive impairment. METHODS: Forty-nine individuals with Parkinson's disease without cognitive impairment participated in a test-retest reliability study. At two outpatient visits 8 days apart, the participants completed comprehensive questionnaires and single-item questions: International Physical Activity Questionnaire-Short Form (IPAQ-SF), Physical Activity Scale for the Elderly (PASE), Saltin-Grimby Physical Activity Level Scale (SGPALS) and Health on Equal Terms (HOET). Test-retest reliability was evaluated using the intraclass correlation coefficient (ICC), standard error of measurement (SEM), limits of agreement, weighted kappa or the Svensson method. RESULTS: Several of the physical activity questionnaires had relatively low test-retest reliability, including the comprehensive questionnaires (IPAQ-SF and PASE). Total physical activity according to IPAQ-SF had an ICC value of 0.46 (95% confidence interval [CI], 0.21-0.66) and SEM was 2891 MET-min/week. The PASE total score had an ICC value of 0.66 (95% CI, 0.46-0.79), whereas the SEM was 30 points. The single-item scales of SGPALS-past six months (SGPALS-6 m) and HOET question 1 (HOET-q1) with longer time frames (6 or 12 months, respectively) showed better results. Weighted kappa values were 0.64 (95% CI, 0.45-0.83) for SGPALS-6 m and 0.60 (95% CI, 0.39-0.80) for HOET-q1, whereas the single-item questions with a shorter recall period had kappa values < 0.40. CONCLUSIONS: Single-item questions with a longer time frame (6 or 12 months) for physical activity were shown to be more reliable than multi-item questionnaires such as the IPAQ-SF and PASE in individuals with Parkinson's disease without cognitive impairments. There is a need to develop a core outcome set to measure physical activity in people with Parkinson's disease, and there might be a need to develop new physical activity questionnaires.

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.

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).

Longitudinal association between housing accessibility and activities of daily living: the role of self-efficacy and control in people ageing with Parkinson's disease.

BACKGROUND: External housing-related control beliefs (HCB) and general self-efficacy (GSE) influence different health outcomes in the general ageing population, but there is no information of their role in people ageing with Parkinson's disease (PD). This study aimed to longitudinally assess the role of external HCB and GSE on the association between housing accessibility and activities of daily living (ADL) among people ageing with PD. METHODS: Baseline and 3-year follow-up data on 130 community-living participants from the Swedish project 'Home and Health in People Ageing with PD' were collected. Assessments addressed housing accessibility, external HCB, GSE, generic ADL and ADL specific to PD. The moderating effects of external HCB and GSE were assessed by including an interaction term in multivariable logistic regression. RESULTS: There were statistically significant interactions between housing accessibility and GSE on ADL (p = 0.03), and housing accessibility and external HCB on PD specific ADL (p = 0.03). After stratifying the analyses by GSE, housing accessibility problems led to more dependence and difficulty in ADL in participants with low GSE (OR 1.14; 95% CI 1.02-1.28). After stratifying by external HCB, housing accessibility increased dependence and difficulty in PD specific ADL in participants with low external HCB (OR 1.35; 95% CI 1.03-1.76). DISCUSSION: The results suggest that housing accessibility predicts ADL in people with PD with GSE and external HCB playing a moderating role for generic ADL and ADL specific to PD, respectively. Further longitudinal studies should validate these findings and explore their potential application in PD-related care and rehabilitation.

Psychometric properties of the external Housing-Related Control Belief Questionnaire among people with Parkinson's disease.

BACKGROUND: Housing-related control beliefs are associated with aspects of health among older people in general. Research on Parkinson's disease (PD) focusing on perceptions of the home are rare and instruments capturing perceived aspects of home have seldom been used. AIMS: To evaluate psychometric properties of the external Housing-related Control Beliefs Questionnaire (HCQ) among people with PD. METHODS: The external HCQ were administrated to 245 participants with PD, (mean age = 69.9 years; mean PD duration = 9.7 years). External HCQ has 16-items, with five response options. The psychometric properties evaluated were data quality, structural validity (factor analysis), floor and ceiling effects, corrected item total correlations, internal consistency and construct validity (testing correlations with relevant constructs according to pre-defined hypotheses). RESULTS: Data quality was high. Structural validity showed a unidimensional construct with removal of two items. Homogeneity was questionable, but strengthened after the removal of the two items. For the 14-item version internal consistency was α = 0.78 and SEM 4.47. Corrected item total correlation ranged between 0.31 and 0.54 and no floor or ceiling effects. Significant correlations with relevant constructs supported the construct validity. CONCLUSIONS: Taken together, the psychometric results suggest a 14-item version of the external HCQ to be sufficiently reliable and valid for use in the PD population. The results pave the way for further studies, using the HCQ to analyse how perceptions of control of the home may be associated with health among people ageing with PD.

Exploring the effects of deep brain stimulation and vision on tremor in Parkinson's disease - benefits from objective methods.

BACKGROUND: Tremor is a cardinal symptom of Parkinson's disease (PD) that may cause severe disability. As such, objective methods to determine the exact characteristics of the tremor may improve the evaluation of therapy. This methodology study aims to validate the utility of two objective technical methods of recording Parkinsonian tremor and evaluate their ability to determine the effects of Deep Brain Stimulation (DBS) of the subthalamic nucleus and of vision. METHODS: We studied 10 patients with idiopathic PD, who were responsive to L-Dopa and had more than 1 year use of bilateral subthalamic nucleus stimulation. The patients did not have to display visible tremor to be included in the study. Tremor was recorded with two objective methods, a force platform and a 3 dimensional (3D) motion capture system that tracked movements in four key proximal sections of the body (knee, hip, shoulder and head). They were assessed after an overnight withdrawal of anti-PD medications with DBS ON and OFF and with eyes open and closed during unperturbed and perturbed stance with randomized calf vibration, using a randomized test order design. RESULTS: Tremor was detected with the Unified Parkinson's Disease Rating Scale (UPDRS) in 6 of 10 patients but only distally (hands and feet) with DBS OFF. With the force platform and the 3D motion capture system, tremor was detected in 6 of 10 and 7 of 10 patients respectively, mostly in DBS OFF but also with DBS ON in some patients. The 3D motion capture system revealed that more than one body section was usually affected by tremor and that the tremor amplitude was non-uniform, but the frequency almost identical, across sites. DBS reduced tremor amplitude non-uniformly across the body. Visual input mostly reduced tremor amplitude with DBS ON. CONCLUSIONS: Technical recording methods offer objective and sensitive detection of tremor that provide detailed characteristics such as peak amplitude, frequency and distribution pattern, and thus, provide information that can guide the optimization of treatments. Both methods detected the effects of DBS and visual input but the 3D motion system was more versatile in that it could detail the presence and properties of tremor at individual body sections.

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 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.

Fall-related activity avoidance in relation to a history of falls or near falls, fear of falling and disease severity in people with Parkinson's disease.

BACKGROUND: There is limited knowledge concerning fall-related activity avoidance in people with Parkinson's disease (PD); such knowledge would be of importance for the development of more efficient PD-care and rehabilitation. This study aimed to examine how fall-related activity avoidance relates to a history of self-reported falls/near falls and fear of falling (FOF) as well as to disease severity in people with PD. METHODS: Data were collected from 251 (61 % men) participants with PD; their median (min-max) age and PD duration were 70 (45-93) and 8 (1-43) years, respectively. A self-administered postal survey preceded a home visit which included observations, clinical tests and interview-administered questionnaires. Fall-related activity avoidance was assessed using the modified Survey of Activities and Fear of Falling in the Elderly (mSAFFE) as well as by using a dichotomous (Yes/No) question. Further dichotomous questions concerned: the presence of FOF and the history (past 6 months) of falls or near falls, followed by stating the number of incidents. Disease severity was assessed according to the Hoehn and Yahr (HY) stages. RESULTS: In the total sample (n = 251), 41 % of the participants reported fall-related activity avoidance; the median mSAFFE score was 22. In relation to a history of fall, the proportions of participants (p < 0.001) that reported fall-related activity avoidance were: non-fallers (30 %), single fallers (50 %) and recurrent fallers, i.e. ≥ 2 falls (57 %). Among those that reported near falls (but no falls), 51 % (26 out of 51) reported fall-related activity avoidance. Of those that reported FOF, 70 % reported fall-related activity avoidance. Fall-related activity avoidance ranged from 24 % in the early PD-stage (HY I) to 74 % in the most severe stages (HY IV-V). CONCLUSIONS: Results indicate that fall-related activity avoidance may be related to a history of self-reported falls/near falls, FOF and disease severity in people with PD. Importantly, fall-related activity avoidance is reported among those that do not fall and already in mild PD-stages (HY I-II). Although further studies are needed, our findings indicate that fall-related activity avoidance needs to be addressed early in order to prevent sedentary behavior and participation restrictions.

The association between indicators of health and housing in people with Parkinson's disease.

BACKGROUND: There are knowledge gaps about the life situation for people ageing with Parkinson's disease (PD), with virtually no understanding of home and health dynamics. Therefore, the aim of the present study was to explore the association between aspects of health and objective as well as perceived housing in people with PD. METHODS: Participants were recruited from three hospitals in the region of Skåne in southern Sweden. The sample for the present study included 231 (62 % men) participants with PD, with a mean age of 75 (min-max, 45-93) years. The data collection procedure included a self-administered postal survey and a subsequent home visit where structured interviews, observations and clinical assessments were administered. To study the association between aspects of health and housing canonical correlation was applied. Twelve variables (6 in the health and 6 in the housing set) were included. This corresponds to about 20 individuals per variable and is considered sufficient to accurately interpret the largest (i.e., first) canonical correlation. RESULTS: The analysis between the health variables and housing variables set yielded two significant pairs of variates with the canonical correlations 0.68 (p < 0.0001) and 0.33 (p = 0.0112), respectively. For the first pair of variates the canonical R(2) was 0.46. The results showed that external control beliefs and behavioral aspects of meaning of home contributed the most to the housing variate, whereas difficulties/dependence in activities of daily living (ADL) and functional limitations contributed the most to the health variate. Although a significant relationship was found for the second canonical correlation, the shared variance between the two variates was considerably lower; R(2) = 0.11. CONCLUSIONS: This study suggests that people with PD who have more functional limitations, difficulties in ADL and are more dependent perceive their homes as less meaningful from a behavioral perspective. Moreover, they tend to rely on external influences managing their housing situation. With this kind of knowledge at hand, health care and social services professionals are in a better position to observe and efficiently address problems related to health and housing among people with PD.

Factors associated with fear of falling in people with Parkinson's disease.

BACKGROUND: This study aimed to comprehensibly investigate potential contributing factors to fear of falling (FOF) among people with idiopathic Parkinson's disease (PD). METHODS: The study included 104 people with PD. Mean (SD) age and PD-duration were 68 (9.4) and 5 (4.2) years, respectively, and the participants' PD-symptoms were relatively mild. FOF (the dependent variable) was investigated with the Swedish version of the Falls Efficacy Scale, i.e. FES(S). The first multiple linear regression model replicated a previous study and independent variables targeted: walking difficulties in daily life; freezing of gait; dyskinesia; fatigue; need of help in daily activities; age; PD-duration; history of falls/near falls and pain. Model II included also the following clinically assessed variables: motor symptoms, cognitive functions, gait speed, dual-task difficulties and functional balance performance as well as reactive postural responses. RESULTS: Both regression models showed that the strongest contributing factor to FOF was walking difficulties, i.e. explaining 60% and 64% of the variance in FOF-scores, respectively. Other significant independent variables in both models were needing help from others in daily activities and fatigue. Functional balance was the only clinical variable contributing additional significant information to model I, increasing the explained variance from 66% to 73%. CONCLUSIONS: The results imply that one should primarily target walking difficulties in daily life in order to reduce FOF in people mildly affected by PD. This finding applies even when considering a broad variety of aspects not previously considered in PD-studies targeting FOF. Functional balance performance, dependence in daily activities, and fatigue were also independently associated with FOF, but to a lesser extent. Longitudinal studies are warranted to gain an increased understanding of predictors of FOF in PD and who is at risk of developing a FOF.

Conceptualizing and prioritizing clinical trial outcomes from the perspectives of people with Parkinson's disease versus health care professionals: a concept mapping study.

BACKGROUND: Focusing clinical investigations on outcomes that are meaningful from an end-user perspective is central in clinical research, particularly in chronic disorders such as Parkinson's disease (PD). However, little is known about how end-users such as people with PD (PwPD) and health care professionals (HCPs) view and prioritize therapeutic outcomes. PURPOSE: To compare the perspectives of PwPD and HCPs regarding prioritized areas for outcome measurement in clinical PD trials. METHODS: Concept mapping was used to identify prioritized outcomes (statements) through focus groups (n = 27; 12 PwPD, 12 HCPs, three researchers), statement sorting and importance rating (n = 38; 19 PwPD, 19 HCPs), followed by quantitative (multidimensional scaling, cluster analysis, procrustes analysis) and qualitative analysis. RESULTS: Sorting of 99 statements by PwPD and HCPs yielded 2D maps (PwPD/HCPs stress values, 0.31/0.21) with eight clusters per group. The correlation between raw sorting data of PwPD and HCPs was 0.80, and there was a significant concordance (m 12 = 0.53; P < 0.001; i.e., r = 0.68) between the spatial arrangements in their respective maps. Qualitatively, the maps from the two groups represented partially different perspectives. There were no significant differences between PwPD and HCP item importance ratings. CONCLUSION: Although similarities dominated, there were differences in how the relationships between items were perceived by the two groups, emanating from different perspectives, i.e., the clinical biomedical ("disease") versus the lived experience ("illness"). This study illustrates the clinical importance of attention to the perspective of PwPD; taking this into account is likely to provide evidence from clinical investigations that are meaningful and interpretable for end-users.

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.

A research-based strategy for managing housing adaptations: study protocol for a quasi-experimental trial.

BACKGROUND: The primary aim of this paper is to describe the design of a project evaluating the effects of using a research-based strategy for managing housing adaptations (HAs). The evaluation targets clients' perspectives in terms of activity, participation, usability, fear of falling, fall incidence, use of mobility devices, and health-related quality of life, and determines the societal effects of HAs in terms of costs. Additional aims of the project are to explore and describe this strategy in relation to experiences and expectations (a) among clients and cohabitants and (b) occupational therapists in ordinary practice. METHODS/DESIGN: This study is a quasi-experimental trial applying a multiphase design, combining quantitative and qualitative data. At the experimental sites, the occupational therapists (OTs) apply the intervention, i.e. a standardized research-based strategy for HA case management. At the control site, the occupational therapists are following their regular routine in relation to HA. Three municipalities in south Sweden will be included based on their population, their geographical dispersion, and their similar organizational structures for HA administration. Identical data on outcomes is being collected at all the sites at the same four time points: before the HA and then 3, 6, and 12 months after the HA. The data-collection methods are semi-structured qualitative interviews, observations, clinical assessments, and certificates related to each client's HA. DISCUSSION: The intervention in this study has been developed and tested through many years of research and in collaboration with practitioners. This process includes methodological development and testing research aimed at identifying the most important outcomes and research targeting current HA case-management procedures in Swedish municipalities. When the study is completed, the results will be used for further optimization of the practice strategy for HA, in close collaboration with the data-collecting OTs. TRIAL REGISTRATION: No: NCT01960582.

The Relationship Between Physical Housing Characteristics, Housing Accessibility and Different Aspects of Health Among Community-Dwelling Older People: A Systematic Review.

Objectives: To synthesize the evidence on the relationships between physical housing characteristics or housing accessibility and different aspects of health among community-dwelling people 60 years and older. Methods: A systematic review of recent evidence with a narrative synthesis was conducted. Results: We included 15 studies and found three themes covering physical housing characteristics or housing accessibility that are associated with aspects of health among community-dwelling older adults: (1) interventions by home modifications targeting housing features both at entrances and indoors; (2) non-interventions targeting indoor features; (3) non-interventions targeting entrance features, that is, the presence of an elevator or stairs at the entrance. The overall quality of evidence across studies was assessed as very low. Discussion: The findings highlight the need for studies with a stronger research design and higher methodological quality that address the physical housing environment in relation to health among older adults to strengthen the body of evidence.

Home and health in people ageing with Parkinson's disease: study protocol for a prospective longitudinal cohort survey study.

BACKGROUND: With an increased life expectancy for the general population as well as for those ageing with chronic diseases, there are major challenges to the affected individuals and their families, but also to health care and societal planning. Most important, an increasing proportion of older people remain living in their ordinary homes despite health decline and disability. However, little is known about the home and health situation of people ageing with Parkinson's disease (PD), and older people are often excluded from PD-research. METHODS/DESIGN: The overall aim of the present project is to generate knowledge on home and health dynamics in people with PD, with an explicit attention to PD-specific symptomatology. We will concentrate on aspects of home and health captured by state-of-the-art methodology from gerontology as well as PD-research, health science and rehabilitation. This study protocol describes a longitudinal cohort survey study that includes a baseline data collection and a 3-year follow-up. Both data collection waves include self-administered questionnaires, structured interviews, clinical assessments and observations during home visits effectuated by research staff with project-specific training. In order to arrive at a follow-up sample of N=160, 250 participants identified by PD specialist nurses are being recruited from three hospitals in southern Sweden. With no lower or upper age limit, only those diagnosed with PD since at least one year were included. The exclusion criteria were: difficulties in understanding or speaking Swedish and/or cognitive difficulties/other reasons making the individual unable to give informed consent or to take part in the majority of the data collection. The data collection targets environmental factors such as assistive devices, social support, physical environmental barriers, accessibility problems and perceived aspects of home. A broad variety of instruments tap PD-specific problems (e.g. freezing of gait, fear of falling) and health-related issues such as general self-efficacy, body functions, activities and participation. DISCUSSION: This project will produce knowledge to the benefit of the development of health care and societal planning that targets people ageing with PD, ultimately promoting activity and participation and an increase of the number of healthy life years for this sub-group of the population.

Characteristics of the personal and environmental components of person-environment fit in very old age: a comparison between people with self-reported Parkinson's disease and matched controls.

BACKGROUND AND AIMS: To investigate differences and similarities in person-environment (P-E) fit problems between very old people with self-reported Parkinson's disease (PD) and matched controls. METHODS: Data collected for the cross-national ENABLE-AGE Survey Study were used to identify people with self-reported PD (n = 20), and to select three matched controls per individual (n = 60). The matching criteria were age (mean = 82 years), sex, country, and type of housing. The data analysis targeted P-E fit (i.e. accessibility) problems, including studying the personal and environmental components separately. The personal component was analyzed in terms of functional limitations, and the environmental component in terms of physical environmental barriers. RESULTS: In comparison to the matched controls, the participants with PD had more functional limitations, used more mobility devices and were subjected to more P-E fit problems, though the number of environmental barriers did not differ from the controls. In the PD sample, P-E fit problems were significantly stronger associated with poor balance and incoordination, and the environmental barriers that generated the most severe P-E fit problems were more often located to the exterior surroundings of the housing compared to the controls. CONCLUSIONS: The novel contribution of this explorative study is the demonstration of the type of knowledge that can be generated by unfolding and comparing the composition of P-E fit (accessibility) problems among people with self-reported PD as compared with matched controls. The knowledge thereby generated can be used to develop more targeted rehabilitation approaches, efficient housing adaptation services and societal planning for people with neurodegenerative disorders.

Subthalamic deep brain stimulation improves smooth pursuit and saccade performance in patients with Parkinson's disease.

BACKGROUND: Deep brain stimulation (DBS) in the subthalamic nucleus (STN) significantly reduces symptoms of Parkinson's disease (PD) such as bradykinesia, tremor and rigidity. It also reduces the need for anti-PD medication, and thereby potential side-effects of L-Dopa. Although DBS in the STN is a highly effective therapeutic intervention in PD, its mechanism and effects on oculomotor eye movement control and particularly smooth pursuit eye movements have to date rarely been investigated. Furthermore, previous reports provide conflicting information. The aim was to investigate how DBS in STN affected oculomotor performance in persons with PD using novel analysis techniques. METHODS: Twenty-five patients were eligible (22 males, 3 females) according to the clinical inclusion criteria: idiopathic PD responsive to L-Dopa and having had bilateral STN stimulation for at least one year to ensure stable DBS treatment. Fifteen patients were excluded due to the strict inclusion criteria applied to avoid interacting and confounding factors when determining the effects of DBS applied alone without PD medication. One patient declined participation. Nine PD patients (median age 63, range 59-69 years) were assessed after having their PD medications withdrawn overnight. They were examined with DBS ON and OFF, with the ON/OFF order individually randomized. RESULTS: DBS ON increased smooth pursuit velocity accuracy (p < 0.001) and smooth pursuit gain (p = 0.005), especially for faster smooth pursuits (p = 0.034). DBS ON generally increased saccade amplitude accuracy (p = 0.007) and tended to increase peak saccade velocity also (p = 0.087), specifically both saccade velocity and amplitude accuracy for the 20 and 40 degree saccades (p < 0.05). Smooth pursuit latency tended to be longer (p = 0.090) approaching normal with DBS ON. Saccade latency was unaffected. CONCLUSIONS: STN stimulation from DBS alone significantly improved both smooth pursuit and saccade performance in patients with PD. The STN stimulation enhancement found for oculomotor performance suggests clear positive implications for patients' ability to perform tasks that rely on visual motor control and visual feedback. The new oculomotor analysis methods provide a sensitive vehicle to detect subtle pathological modifications from PD and the functional enhancements produced by STN stimulation from DBS alone.

A theoretical framework for addressing fear of falling avoidance behavior in Parkinson's disease.

Postural instability in Parkinson's disease (PD) is associated with several downstream consequences that ultimately lead to a greater risk of falling. Among the prominent downstream consequences is fear of falling (FOF), which is both common and problematic in PD. It can lead to a vicious cycle of FOF avoidance behavior that results in more sedentary behavior, physical deconditioning, and weakening of already impaired balance systems. This, in turn, may make the person with PD more susceptible to a future fall even with benign daily tasks. While FOF activity avoidance can be adaptive (appropriate), it can also be maladaptive (inappropriate or exaggerated). When this adaptive and maladaptive FOF avoidance behavior is contextualized to gait/balance performance, it provides a theoretical framework that can be used by clinicians to match patterns of behavior to a concordant treatment approach. In the theoretical framework proposed in this perspective, four different patterns related to FOF avoidance behavior and gait/balance performance are suggested: appropriate avoiders, appropriate non-avoiders, inappropriate avoiders, and inappropriate non-avoiders. For each of the four FOF avoidance behavior patterns, this paper also provides suggested treatment focuses, approaches and recommendations.

Environmental barriers and housing accessibility problems for people with Parkinson's disease: A three-year perspective.

BACKGROUND: Although housing accessibility is associated with important health outcomes in other populations, few studies have addressed this in a Parkinson's disease population. AIM: To determine the most severe environmental barriers in terms of housing accessibility problems and how these evolved over 3 years among people with Parkinson's disease. MATERIAL AND METHODS: 138 participants were included (men = 67%; mean age = 68 years). The most severe environmental barrier were identified by the Housing Enabler instrument and ranked in descending order. The paired t-test was used to analyse changes in accessibility problems over time. RESULTS: The top 10 barriers remained largely unchanged over 3 years, but with notable changes in order and magnitude. 'No grab bar in hygiene area' and 'Stairs only route' were top-ranked in generating accessibility problems at baseline but decreased significantly (p = 0.041; p = 0.002) at follow-up. 'Difficulties to reach refuse bin' was top-ranked at follow-up, with a significant increase (p < 0.001) of related accessibility problems. CONCLUSIONS AND SIGNIFICANCE: The new knowledge about how accessibility problems evolve over time could be used by occupational therapists to recommend more effective housing adaptations taking the progressive nature of Parkinson's disease into account. On societal level, the results could be used to address accessibility problems systematically.