Martin W G Brinkhof

Mortality and Longevity after a Spinal Cord Injury: Systematic Review and Meta-Analysis

Background/Aims: Mortality and longevity studies of spinal cord injury (SCI) are essential for informing healthcare systems and policies. This review evaluates the current evidence among people with SCIs worldwide in relation to the WHO region and country income level; demographic and lesion characteristics; and in comparison with the general population. Methods: A systematic review of relevant databases for original studies. Pooled estimates were derived using random effects meta-analysis, restricted to traumatic SCI. Results: Seventy-four studies were included. In-hospital mortality varied, with pooled estimates of 24.1% (95% confidence interval (CI) 14.1-38.0), 7.6% (95% CI 6.3-9.0), 7.0% (95% CI 1.5-27.4), and 2.1% (95% CI 0.9-5.0) in the WHO regions of Africa, the Americas, Europe and Western Pacific. The combined estimate for low- and middle-income countries was nearly three times higher than for high-income countries. Pooled estimates of first-year survival were 86.5% (95% CI 75.3-93.1), 95.6% (95% CI 81.0-99.1), and 94.0% (95% CI 93.3-94.6) in the Americas, Europe and Western Pacific. Pooled estimates of standardized mortality ratios in tetraplegics were 2.53 (2.00-3.21) and 2.07 (1.47-2.92) in paraplegics. Conclusion: This study found substantial variation in mortality and longevity within the SCI population, compared to the general population, and between WHO regions and country income level. Improved standardization and quality of reporting is needed to improve inferences regarding the extent to which mortality outcomes following an SCI are related to healthcare systems, services and policies.

TOWARD STANDARDIZED REPORTING FOR A COHORT STUDY ON FUNCTIONING: THE SWISS SPINAL CORD INJURY COHORT STUDY

OBJECTIVE Functioning is an important outcome to measure in cohort studies. Clear and operational outcomes are needed to judge the quality of a cohort study. This paper outlines guiding principles for reporting functioning in cohort studies and addresses some outstanding issues. DESIGN Principles of how to standardize reporting of data from a cohort study on functioning, by deriving scores that are most useful for further statistical analysis and reporting, are outlined. The Swiss Spinal Cord Injury Cohort Study Community Survey serves as a case in point to provide a practical application of these principles. METHODS AND RESULTS Development of reporting scores must be conceptually coherent and metrically sound. The International Classification of Functioning, Disability and Health (ICF) can serve as the frame of reference for this, with its categories serving as reference units for reporting. To derive a score for further statistical analysis and reporting, items measuring a single latent trait must be invariant across groups. The Rasch measurement model is well suited to test these assumptions. CONCLUSION Our approach is a valuable guide for researchers and clinicians, as it fosters comparability of data, strengthens the comprehensiveness of scope, and provides invariant, interval-scaled data for further statistical analyses of functioning.

Metric properties of the Spinal Cord Independence Measure -: Self report in a community survey

OBJECTIVE The Spinal Cord Independence Measure - Self Report (SCIM-SR) is a self-report instrument for assessing functional independence of persons with spinal cord injury. This study examined the internal construct validity and reliability of the SCIM-SR, when administered in a community survey, using the Rasch measurement model. METHODS Rasch analysis of data from 1,549 individuals with spinal cord injury who completed the SCIM-SR. RESULTS In the initial analysis no fit to the Rasch model was achieved. Items were grouped into testlets to accommodate the substantial local dependency. Due to the differential item functioning for lesion level and degree, spinal cord injury-specific sub-group analyses were conducted. Fit to the Rasch model was then achieved for individuals with tetraplegia and complete paraplegia, but not for those with incomplete paraplegia. Comparability of ability estimates across sub-groups was attained by anchoring all sub-groups on a testlet. CONCLUSION The SCIM-SR violates certain assumptions of the Rasch measurement model, as shown by the local dependency and differential item functioning. However, an intermediate solution to achieve fit in 3 out of 4 spinal cord injury sub-groups was found. For the time being, therefore, it advisable to use this approach to compute Rasch-transformed SCIM-SR scores.

Subjective Caregiver Burden and Caregiver Satisfaction: The Role of Partner Relationship Quality and Reciprocity

OBJECTIVE To explore the effect of relationship quality and reciprocity in partnerships on subjective caregiver burden and caregiver satisfaction in partners of persons with a severe physical disability (spinal cord injury). DESIGN Cross-sectional, observational. SETTING Community setting. PARTICIPANTS Caregiving partners of persons with spinal cord injury (N=118). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURES Subjective caregiver burden measured by the Zarit Burden Interview (short form) and caregiver satisfaction measured by a single item on feelings of satisfaction resulting from the caregiver role. RESULTS Caregiving partners who rated their relationship quality as high encountered less subjective caregiver burden (β=-1.10; 95% confidence interval [CI], -1.47 to -0.72; P<.001) and more caregiver satisfaction (odds ratio [OR], 1.18; 95% CI, 1.01-1.45; P=.049). These associations persisted even after controlling for sociodemographic characteristics, lesion severity of the care receiver, and objective caregiver burden. Partners who indicated high reciprocity in their relationship to the care receiver indicated less subjective caregiver burden and more caregiver satisfaction when relationship quality was excluded from the final models; however, the effect of reciprocity on subjective burden (β=-.38; 95% CI, -3.71 to 2.95; P=.82) and caregiver satisfaction (OR, 1.21; 95% CI, 0.28-5.22; P=.80) disappeared when including relationship quality. CONCLUSIONS Results highlight the importance of relationship quality as a target for couple interventions aimed at reducing subjective caregiver burden and increasing satisfaction in the caregiving role.

Metric properties of the Utrecht Scale for Evaluation of Rehabilitation-Participation (USER-Participation) in persons with spinal cord injury living in Switzerland

OBJECTIVE To examine the metric properties of the Utrecht Scale for Evaluation of Rehabilitation-Participation (USER-Participation) in persons with spinal cord injury in Switzerland from a classical and item response theory perspective. DESIGN Cross-sectional survey. SUBJECTS Persons with spinal cord injury living in the Swiss community (n = 1,549). METHODS Score distributions and internal consistency were evaluated using Classical Test Theory. The Restrictions and Satisfaction scales were subjected to Rasch analysis. Anchored analyses were performed to account appropriately for items with structural missing. RESULTS Internal consistency was good for the Restrictions (α = 0.90) and Satisfaction scales (α = 0.90), but not for the Frequency scale (α = 0.65). Rasch analyses showed acceptable model fit for the Restrictions and Satisfaction scales after collapsing response categories of some items and merging some items into testlets. Differential item functioning was small. Anchoring allowed inclusion of the item work/education in the Restrictions scale and work/education and/or partner relationship in the Satisfaction scale. CONCLUSION The Restrictions and Satisfaction scales of the USER-Participation showed satisfactory metric properties. The Frequency scale showed fewer optimal properties, but nonetheless provides important additional information regarding participation. Conversion tables were performed to transform USER-Participation raw scores into a 0-100 interval scale using Rasch-based ability estimates for use in epidemiological studies.

Psychometric properties of the Nottwil Environmental Factors Inventory Short Form

OBJECTIVES To examine the psychometric properties of the Nottwil Environmental Factors Inventory Short Form using Rasch analysis; to determine its construct validity and internal consistency; and to develop a metric for scoring. DESIGN Cross-sectional psychometric study. Construct validity of the Nottwil Environmental Factors Inventory Short Form, including model fit, person and item fit, local item dependence, dimensionality, and differential item functioning (DIF), was investigated with Rasch analysis. Internal consistency was assessed with Cronbach alpha and item-total correlations. SETTING Community. PARTICIPANTS Swiss residents aged >16 years and living with traumatic or nontraumatic spinal cord injury (SCI) (N=1549). INTERVENTIONS Not applicable. MAIN OUTCOME MEASURE The Nottwil Environmental Factors Inventory Short Form, a 14-item questionnaire developed to assess perceived impact of environmental barriers on participation. RESULTS Local dependencies between items addressing a similar content could be solved by creating a testlet. With 1 testlet there was strong evidence for unidimensionality of the Nottwil Environmental Factors Inventory Short Form. Although person-item targeting revealed a floor effect, indicating few perceived environmental barriers to participation in the Swiss SCI population, the item fit was good. Only a few items presented DIF. The Nottwil Environmental Factors Inventory Short Form showed good internal consistency (α=.82). CONCLUSIONS This psychometric analysis supports the use of the Nottwil Environmental Factors Inventory Short Form to evaluate perceived environmental barriers to participation in persons with SCI living in the community.

Longitudinal study of social participation and well-being among persons with spinal cord injury and their partners (pro-WELL)

Purpose Social participation is an important determinant of well-being. Among persons with disabilities, and with spinal cord injury (SCI) in particular, opportunities for social participation are restricted and may impact well-being. The longitudinal pro-WELL study aims to investigate associations of 2 major domains of social participation with well-being: (1) availability and quality of close social relationships and (2) acting in core social roles (eg, paid work). The joint inclusion of persons with SCI and their partners is a major innovative aspect of this study enabling an in-depth analysis of interpersonal dynamics in coping with disability. Participants Pro-WELL is a nested project of the Swiss Spinal Cord Injury Cohort Study (SwiSCI) and involves community-dwelling persons aged 30–65 with SCI and their partners living in Switzerland. Baseline data were collected from mid-2015 to early 2016 by telephone interviews and questionnaires. The first and second follow-up assessments are scheduled with a 6 months interval. Findings to date The baseline sample consists of 133 persons with SCI and their partners. We provide an overview of baseline characteristics and well-being and describe recruitment outcomes and participation rates. A comprehensive non-response analysis demonstrates adequate representation of the source population with negligible selection bias regarding sociodemographic and lesion characteristics. Future plans The prospective data collection and analysis of month 6 and 12 assessments are ongoing and tests of the main research hypotheses will be performed. Findings will be disseminated through peer-reviewed journals and scientific conferences. A workshop and a newsletter on study findings are proposed to feed back findings to participants and other stakeholders.

Determinants of handbike use in persons with spinal cord injury: results of a community survey in Switzerland

Abstract Purpose: To examine the prevalence and determinants of handbike use in persons living with spinal cord injury in Switzerland. Method: A population-based cross-sectional survey in Switzerland. Results: The crude prevalence of handbike use among the 1549 participants was 22.6%, varying between 25.3% in men and 17.7% in women. Prevalence was higher in complete than in incomplete spinal cord injury (SCI) (41.5% versus 11.9% in paraplegia, 25.6% versus 11.1% in tetraplegia). Multivariable analysis of handbike use confirmed differences with lesion characteristics and gender and showed a decline with age, lowest rates in the low-income group, variation with language, but no association with level of education or cause of spinal cord injury. In total, 45.8% of users reported to engage in handcycling at least once a week. Frequent contextual reasons for refraining from handcycling were: no interest (26%); inability due to disability (20%); unfamiliarity with the handbike (19%) and financial constraints (14%). Conclusions: Conditional on the major determinants that include demographic factors and lesion characteristics, main barriers involve contextual factors that can principally be overcome. Our findings thus suggest scope for promoting handcycling as a means towards a healthy and more physically active lifestyle in persons living with SCI. Implications for Rehabilitation Handcycling is an effective means of improving health and quality of life of persons with a spinal cord injury. Persons with the following traits are most likely to use the handbike: persons younger than 62 years, with a complete paraplegia, who are German-speaking (vs. French/Italian) and having a middle or high net income. Indicated reasons for not using a handbike varied by SCI characteristics and included disinterest, inability related to the level of impairment, unfamiliarity and financial costs. Barriers that involve the above mentioned contextual factors can principally be overcome by targeted policy or information campaigns.

Age-related variation in mobility independence among wheelchair users with spinal cord injury: A cross-sectional study

Objective: To evaluate age-related variation in mobility independence among community-living wheelchair users with spinal cord injury (SCI). Design: Community Survey (2011–2013) as part of the Swiss Spinal Cord Injury Cohort Study. Setting: Community. Participants: Individuals aged 16 years or older with traumatic or non-traumatic SCI permanently residing in Switzerland and using a wheelchair for moving around moderate distances (10–100 m). Interventions: Not applicable. Outcome Measures: Mobility-related items of the Spinal Cord Independence Measure-Self Report were matched to the three principal domains “changing basic body position,” “transferring oneself” and “moving around.” Binary outcomes (“independence” vs. “no independence”) were created for every domain and analyzed using multivariable logistic regression (adjusted for sex, socioeconomic factors, SCI characteristics, and health conditions). Results: Regression analyses (N = 949; 27% women; median age 51, interquartile range 41–61) showed a decline in the odds of independence (odds ratio; 95% confidence interval) with increasing age for “changing basic body position” (age 16–30 (reference), 31–45 (0.99; 0.53–1.83), 46–60 (0.64; 0.33–1.21), 61–75 (0.45; 0.22–0.92), 76+ (0.18; 0.07–0.44); P < 0.001), “transferring oneself” (age 16–30 (reference), 31–45 (0.77; 0.37–1.61), 46–60 (0.39; 0.18–0.84), 61+ (0.05; 0.02–0.14); P < 0.001), and “moving around” (age 16–30 (reference), 31–45 (0.79; 0.42–1.48), 46–60 (0.49; 0.26–0.94), 61–75 (0.49; 0.24–1.01), 75+ (0.11; 0.04–0.30); P < 0.001). Conclusions: Mobility independence was negatively associated with age in wheelchair users with SCI. Future longitudinal analyses are required to gain further insights into the causal factors for the age-related decline.

Vitality and mental health in disability: Associations with social relationships in persons with spinal cord injury and their partners

BACKGROUND Various social relationship constructs have been proposed to affect mental health. However, these constructs have rarely been studied in a comprehensive way in persons with chronic disabilities and their partners, inhibiting researchers from evaluating their relative importance. OBJECTIVE To investigate 1) the variation in the quantity and quality of social relationships in persons with spinal cord injury (SCI) and their partners; 2) dyadic coherence within social relationship constructs; 3) the interrelationships between social relationship constructs; and 4) the associations of social relationship constructs with vitality and mental health. METHODS Cross-sectional survey data from 133 couples of persons with SCI and their partners was used. Quantitative (social networks) and qualitative aspects (social support, relationship quality, loneliness, and reciprocity in partnerships) of social relationships were assessed. Correlations were performed to analyse dyadic coherence and interrelationships of social relationship constructs and multivariable regressions were applied to examine associations with vitality and mental health. RESULTS Loneliness, larger social networks and higher relationship quality were more prevalent in SCI. All social relationship constructs, apart from loneliness, were more similar within couples than between couples and the interrelationships between different constructs were small. Qualitative aspects of relationships were more important than the quantitative aspects in their associations to vitality and mental health. These associations were most consistent for loneliness, reciprocity and relationship quality in both groups. CONCLUSIONS In the long-term management of community functioning in persons with SCI and their partners, the fostering of high quality intimate relationships should take priority.