Johanne Higgins

Disablement following stroke

PURPOSE Stroke is the most disabling chronic condition, newly affecting 35000 persons in Canada each year. Because of declining fatality, a growing number of persons will have to cope with stroke-related disability. The purpose of this paper is to describe the disabilities experienced by persons with stroke during the first year and explore the evolution of impairment, disability, handicap and health-related quality of life. SUBJECTS The data for this paper come from a series of longitudinal and cross-sectional studies, collectively known as the McGill Stroke Rehabilitation Research Program. RESULTS Within the first week post-stroke, getting out of bed and walking over a short distance, even with assistance, was a strong predictor of discharge home. Most of the improvement in measures of impairment and disability occurred during the first month and, by 3 months, there was still considerable room for improvement in all measures: 85% of persons were still impaired on gait speed, 78% had not reached age-specific norms for upper extremity function, 68% still demonstrated slow physical mobility, 37% needed some assistance with basic activities of daily living and 29% were still impaired on balance. By 1 year, 73% of persons scored the maximum for basic activities of daily living but 51 and 67% of persons reported their physical health and mental health to be lower than expected. Among a hardy group of stroke survivors, still living in the community 1 year post-stroke, the most striking area of difficulty was endurance, as measured by the 6 minute walk test. Those subjects well enough to complete this task (50% of sample) were able to walk, on average, only 250 metres, equivalent to 40% of their predicted ability. This series of snapshots taken at different points in time suggests that much of the improvement in impairment and disability occurs during the first month and then reaches a plateau. Handicap and quality of life continue to be issues later. Rehabilitation strategies need to consider the multifaceted nature of disablement, which in itself changes with time post-stroke.

Is neuroplasticity in the central nervous system the missing link to our understanding of chronic musculoskeletal disorders

BackgroundMusculoskeletal rehabilitative care and research have traditionally been guided by a structural pathology paradigm and directed their resources towards the structural, functional, and biological abnormalities located locally within the musculoskeletal system to understand and treat Musculoskeletal Disorders (MSD). However the structural pathology model does not adequately explain many of the clinical and experimental findings in subjects with chronic MSD and, more importantly, treatment guided by this paradigm fails to effectively treat many of these conditions.DiscussionIncreasing evidence reveals structural and functional changes within the Central Nervous System (CNS) of people with chronic MSD that appear to play a prominent role in the pathophysiology of these disorders. These neuroplastic changes are reflective of adaptive neurophysiological processes occurring as the result of altered afferent stimuli including nociceptive and neuropathic transmission to spinal, subcortical and cortical areas with MSD that are initially beneficial but may persist in a chronic state, may be part and parcel in the pathophysiology of the condition and the development and maintenance of chronic signs and symptoms. Neuroplastic changes within different areas of the CNS may help to explain the transition from acute to chronic conditions, sensory-motor findings, perceptual disturbances, why some individuals continue to experience pain when no structural cause can be discerned, and why some fail to respond to conservative interventions in subjects with chronic MSD. We argue that a change in paradigm is necessary that integrates CNS changes associated with chronic MSD and that these findings are highly relevant for the design and implementation of rehabilitative interventions for this population.SummaryRecent findings suggest that a change in model and approach is required in the rehabilitation of chronic MSD that integrate the findings of neuroplastic changes across the CNS and are targeted by rehabilitative interventions. Effects of current interventions may be mediated through peripheral and central changes but may not specifically address all underlying neuroplastic changes in the CNS potentially associated with chronic MSD. Novel approaches to address these neuroplastic changes show promise and require further investigation to improve efficacy of currents approaches.

Incorporating the International Classification of Functioning, Disability, and Health (ICF) into an Electronic Health Record to Create Indicators of Function: Proof of Concept Using the SF-12

OBJECTIVE The purpose of this proof-of-concept study was to assess the feasibility of using a generic health measure to create coded functional status indicators and compare the characterization of a stroke population using coded functional indicators and using health-related quality-of-life summary measures alone. DESIGN Multiple raters assigned International Classification of Functioning, Disability, and Health (ICF) codes to the items of the 12-Item Short Form Health Survey (SF-12). Data for comparing the information from the SF-12 and from ICF codes were derived from the Montreal Stroke Cohort Study that was set up to examine the long-term impact of stroke. Available for analysis were data from 604 persons with stroke, average age 69 years, and 488 controls, average age 62 years. MEASUREMENT The SF-12 provides two summary scores, one for physical health and one for mental health. Domains of the ICF are coded to three digits, before the decimal; specific categorizations of impairments, activity limitations, and participation restrictions are coded to four digits before the decimal. RESULTS Persons with stroke scored, on average, approximately 10 points lower than controls on physical and mental health. The ICF coding indicated that this was attributed, not surprisingly, to greater difficulty in doing moderate activities including housework, climbing stairs, and working and was not attributed to differences in pain. Differences in mental health were attributed most strongly to greater fatigue (impairment in energy), but all areas of mental health were affected to some degree. CONCLUSION The ICF coding provided enhanced functional status information in a format compatible with the structure of administrative health databases.

A better screening tool for HIV-associated neurocognitive disorders: is it what clinicians need?

Objective:Existing screening tools for HIV-Associated Neurocognitive Disorders (HAND) may lack the accuracy required for clinical use. We hypothesized that the diagnostic accuracy of the Montreal Cognitive Assessment (MoCA) as a screening tool for HAND might be improved with a stronger scoring methodology. Design:Two hundred HIV-positive participants aged 18–65 years completed the MoCA and a battery of neuropsychological tests. Methods:HAND diagnosis was established according to the Frascati criteria, and an NPZ-8 score was also calculated. Rasch analysis was applied to the MoCA items to create a quantitative score. Results:The optimal cut-off on the quantitative MoCA for detecting impairment as per Frascati criteria yielded a sensitivity of 0.74 and a specificity of 0.68. Overall accuracy was 0.79 (95% CI: 0.73–0.85), an improvement over standard scoring methods. However, whether cognition was quantified with the quantitative MoCA or with NPZ-8, there was substantial overlap between diagnostic categories; several individuals categorized as impaired had better overall cognitive function as assessed by NPZ-8 or quantitative MoCA than those classified as normal using standard criteria. Conclusion:Quantifying performance on MoCA items through Rasch analysis improves its accuracy as a screening tool for HAND, and demonstrates that cognition can be measured as a unidimensional construct in HIV, at least at the level of precision of bedside testing. However, the current categorical diagnostic approach to HAND is poorly aligned with summary measures of cognitive ability. Measuring cognition as a quasi-continuous construct may be more relevant than conventional HAND diagnostic categories for many clinical purposes.

Psychometric evaluation of the Disabilities of the Arm, Shoulder and Hand (DASH) with Dupuytren’s contracture: validity evidence using Rasch modeling

BackgroundDupuytren’s contracture is a progressive, fibroproliferative disorder that causes fixed finger contractures and can lead to disability. With the advances of new therapeutic interventions, the necessity to assess the functional repercussions of this condition using valid, reliable and sensitive outcome measures is of growing interest. The Disabilities of the Arm, Shoulder and Hand (DASH) is one frequently used patient-reported outcome measure but its reliability and validity have never been demonstrated specifically for a population affected with Dupuytren’s contracture. The objective of this study was to evaluate the psychometric properties of the DASH, with focus on validity evidence using the Rasch measurement model.MethodsSecondary analysis was performed on data collected as part of a randomised clinical trial. One hundred fifty-three participants diagnosed with Dupuytren’s contracture completed the DASH at four time points (pre-op, 3, 6 and 12 months post-op). Baseline data were analysed using traditional analysis and to test whether they adhered to the expectations of the Rasch model. Post-intervention data were subsequently included and analyzed to determine the effect of the intervention on the items.ResultsDASH scores demonstrated large ceiling effects at all time points. Initial fit to the Rasch model revealed that the DASH did not adhere to the expectations of the Rasch partial credit model (χ2 = 119.92; p < 0.05). Multiple items displayed inadequate response categories and two items displayed differential item functioning by gender. Items were transformed and one item deleted leading to an adequate fit. Remaining items fit the Rasch model but still do not target well the population under study.ConclusionsThe original version of the 30-item DASH did not display adequate validity evidence for use in a population with Dupuytren’s contracture. Further development is required to improve the DASH for this population.

Combining rTMS and Task-Oriented Training in the Rehabilitation of the Arm after Stroke: A Pilot Randomized Controlled Trial.

Introduction. Repetitive transcranial magnetic stimulation (rTMS) is a promising technique for promoting rehabilitation of arm function after stroke. The feasibility and impact of rTMS as an adjunct to traditional task-oriented training to improve arm function have not yet been demonstrated. Objective. Evaluate the feasibility of a randomized controlled trial aimed at determining the efficacy of rTMS as an adjunct to task-oriented therapy in facilitating restoration of arm function after stroke. Methods. Stratified block-randomized controlled trial set in the general community. Eleven stroke persons with mild to severe arm deficits were recruited and randomized to receive 8 sessions of real-rTMS or sham-rTMS followed by ninety minutes of arm tasks designed to improve function. Results. Medium to large, statistically significant effect sizes (0.49 to 1.63) were observed in both groups on several measures of arm function at the postintervention evaluation. Three out of four subjects in the real-TMS condition showed increased levels of corticomotor excitability after the first stimulation session. Conclusions. Preliminary evidence suggests that an rTMS protocol potent enough to induce transient increases in cortical excitability of the lesioned hemisphere is feasible but did not show promising results as an adjunct to task-specific training. This trial is registration with Clinical Trials.gov NCT00850408.

Maximizing post-stroke upper limb rehabilitation using a novel telerehabilitation interactive virtual reality system in the patient's home: study protocol of a randomized clinical trial

BACKGROUND Telerehabilitation (TR), or the provision of rehabilitation services from a distance using telecommunication tools such as the Internet, can contribute to ensure that patients receive the best care at the right time. This study aims to assess the effect of an interactive virtual reality (VR) system that allows ongoing rehabilitation of the upper extremity (UE) following a stroke, while the person is in their own home, with offline monitoring and feedback from a therapist at a distance. METHODS/DESIGN A single-blind (evaluator is blind to group assignment) two-arm randomized controlled trial is proposed, with participants who have had a stroke and are no longer receiving rehabilitation services randomly allocated to: (1) 4-week written home exercise program, i.e. usual care discharge home program or (2) a 4-week home-based TR exercise program using VR in addition to usual care i.e. treatment group. Motor recovery of the UE will be assessed using the Fugl-Meyer Assessment-UE and the Box and Block tests. To determine the efficacy of the system in terms of functional recovery, the Motor Activity Log, a self-reported measure of UE use will be used. Impact on quality of life will be determined using the Stroke Impact Scale-16. Lastly, a preliminary cost-effectiveness analysis will be conducted using costs and outcomes for all groups. DISCUSSION Findings will contribute to evidence regarding the use of TR and VR to provide stroke rehabilitation services from a distance. This approach can enhance continuity of care once patients are discharged from rehabilitation, in order to maximize their recovery beyond the current available services.

Addressing Neuroplastic Changes in Distributed Areas of the Nervous System Associated With Chronic Musculoskeletal Disorders

Present interventions utilized in musculoskeletal rehabilitation are guided, in large part, by a biomedical model where peripheral structural injury is believed to be the sole driver of the disorder. There are, however, neurophysiological changes across different areas of the peripheral and central nervous systems, including peripheral receptors, dorsal horn of the spinal cord, brain stem, sensorimotor cortical areas, and the mesolimbic and prefrontal areas associated with chronic musculoskeletal disorders, including chronic low back pain, osteoarthritis, and tendon injuries. These neurophysiological changes appear not only to be a consequence of peripheral structural injury but also to play a part in the pathophysiology of chronic musculoskeletal disorders. Neurophysiological changes are consistent with a biopsychosocial formulation reflecting the underlying mechanisms associated with sensory and motor findings, psychological traits, and perceptual changes associated with chronic musculoskeletal conditions. These changes, therefore, have important implications in the clinical manifestation, pathophysiology, and treatment of chronic musculoskeletal disorders. Musculoskeletal rehabilitation professionals have at their disposal tools to address these neuroplastic changes, including top-down cognitive-based interventions (eg, education, cognitive-behavioral therapy, mindfulness meditation, motor imagery) and bottom-up physical interventions (eg, motor learning, peripheral sensory stimulation, manual therapy) that induce neuroplastic changes across distributed areas of the nervous system and affect outcomes in patients with chronic musculoskeletal disorders. Furthermore, novel approaches such as the use of transcranial direct current stimulation and repetitive transcranial magnetic stimulation may be utilized to help renormalize neurological function. Comprehensive treatment addressing peripheral structural injury as well as neurophysiological changes occurring across distributed areas of the nervous system may help to improve outcomes in patients with chronic musculoskeletal disorders.

Development of a method for quantifying cognitive ability in the elderly through adaptive test administration

BACKGROUND The field of geriatric medicine has identified a need for an evaluative tool that can rapidly quantify global cognitive ability and accurately monitor change over time in patients with a wide range of impairments. We hypothesized that the development of an adaptive test approach to cognitive measurement would help to meet that need. This study aimed to provide evidence for the interpretability of scores obtained from a novel, adaptive approach to cognitive assessment, called the Geriatric Rapid Adaptive Cognitive Estimate (GRACE) method. METHODS An adaptive method for cognitive assessment was developed using data from 185 patients referred for geriatric cognitive assessment, and pilot tested in an additional 137 patients. Correlations between test scores and between rank orders of patients were computed to examine the reliability and validity of cognitive ability scores obtained by (1) administering test questions out of their usual order, (2) administering only a subset of questions, and (3) administering questions adaptively using simplified selection rules based on the most difficult question passed. RESULTS Cognitive ability scores obtained with the GRACE method correlated highly with the Montreal Cognitive Assessment (MoCA) scores (r = 0.93) and ranked patients similarly in order of ability (r > 0.87). A simplified adaptive testing algorithm for pencil-and-paper assessment demonstrated moderately high correlations with scores obtained from administering the full set of MMSE and MoCA items as well as the MoCA items alone. CONCLUSIONS Scores from the GRACE method can be obtained easily in 5-10 minutes, reducing test burden. The resulting numeric score quantifies cognitive ability, allowing clinicians to compare patients and monitor change in global cognition over time. The adaptive nature of this method allows for evaluation of persons across a broader range of cognitive ability levels than currently available tests.

A measure of early physical functioning (EPF) post-stroke.

OBJECTIVE To develop a comprehensive measure of Early Physical Functioning (EPF) post-stroke quantified through Rasch analysis and conceptualized using the International Classification of Functioning Disability and Health (ICF). DESIGN An observational cohort study. SUBJECTS A cohort of 262 subjects (mean age 71.6 (standard deviation 12.5) years) hospitalized post-acute stroke. METHODS Functional assessments were made within 3 days of stroke with items from valid and reliable indices commonly utilized to evaluate stroke survivors. Information on important variables was also collected. Principal component and Rasch analysis confirmed the factor structure, and dimensionality of the measure. Rasch analysis combined items across ICF components to develop the measure. Items were deleted iteratively, those retained fit the model and were related to the construct; reliability and validity were assessed. RESULTS A 38-item unidimensional measure of the EPF met all Rasch model requirements. The item difficulty matched the person ability (mean person measure: -0.31; standard error 0.37 logits), reliability of the person-item-hierarchy was excellent at 0.97. Initial validity was adequate. CONCLUSION The 38-item EPF measure was developed. It expands the range of assessment post acute stroke; it covers a broad spectrum of difficulty with good initial psychometric properties that, once revalidated, can assist in planning and evaluating early interventions.