Return to Employment After Stroke in Young Adults: How Important Is the Speed and Energy Cost of Walking?

Background and Purpose- A quarter of individuals who experience a stroke are under the age of 65 years (defined as young adults), and up to 44% will be unable to return to work poststroke, predominantly because of walking difficulties. No research study has comprehensively analyzed walking performance in young adult's poststroke. The primary aim of this study is to investigate how a stroke in young adults affects walking performance (eg, walking speed and metabolic cost) compared with healthy age-matched controls. The secondary aim is to determine the predictive ability of walking performance parameters for return to employment poststroke. Methods- Forty-six individuals (18-40 years: n=6, 41-54 years: n=21, 55-65 years: n=19) who have had a stroke and 15 healthy age-matched able-bodied controls were recruited from 6 hospital sites in Wales, United Kingdom. Type, location, cause of stroke, and demographic factors (eg, employment status) were recorded. Temporal and spatial walking parameters were measured using 3-dimensional gait analysis. Metabolic energy expenditure and metabolic cost of walking were captured during 3 minutes of walking at self-selected speed from measurements of oxygen consumption. Results- Stroke participants walked slower (P<0.004) and less efficiently (P<0.002) than the controls. Only 23% of stroke participants returned to employment poststroke. Walking speed was the strongest predictor (sensitivity, 0.90; specificity, 0.82) for return to work (P=0.004) with a threshold of 0.93 m/s identified: individuals able to walk faster than 0.93 m/s were significantly more likely to return to work poststroke than those who walked slower than this threshold. Conclusions- This study is the first to capture walking performance parameters of young adults who have had a stroke and identifies slower and less efficient walking. Walking speed emerged as the strongest predictor for return to employment. It is recommended that walking speed be used as a simple but sensitive clinical indicator of functional performance to guide rehabilitation and inform readiness for return to work poststroke.

The gait profile score characterises walking performance impairments in young stroke survivors.

BACKGROUND: The Gait Profile Score (GPS) provides a composite measure of the quality of joint movement during walking, but the relationship between this measure and metabolic cost, temporal (e.g. walking speed) and spatial (e.g. stride length) parameters in stroke survivors has not been reported. RESEARCH QUESTION: The aims of this study were to compare the GPS (paretic, non-paretic, and overall score) of young stroke survivors to the healthy able-bodied control and determine the relationship between the GPS and metabolic cost, temporal (walking speed, stance time asymmetry) and spatial (stride length, stride width, step length asymmetry) parameters in young stroke survivors to understand whether the quality of walking affects walking performance in stroke survivors. METHODS: Thirty-nine young stroke survivors aged between 18 and 65years and 15 healthy age-matched able-bodied controls were recruited from six hospital sites in Wales, UK. Joint range of motion at the pelvis, hip, knee and ankle, and temporal and spatial parameters were measured during walking on level ground at self-selected speed with calculation of the Gait Variable Score and then the GPS. RESULTS: GPS for the paretic leg (9.40° (8.60-10.21) p < 0.001), non-paretic leg (11.42° (10.20-12.63) p < 0.001) and overall score (11.18° (10.26-12.09) p < 0.001)) for stroke survivors were significantly higher than the control (4.25° (3.40-5.10), 5.92° (5.11 (6.73)). All parameters with the exception of step length symmetry ratio correlated moderate to highly with the GPS for the paretic, non-paretic, and/or overall score (ρ = <-0.732 (p < 0.001)). SIGNIFICANCE: The quality of joint movement during walking measured via the GPS is directly related to the speed and efficiency of walking, temporal (stance time symmetry) and spatial (stride length, stride width) parameters in young stroke survivors.

Dendritic cell uptake of human apoptotic and necrotic neutrophils inhibits CD40, CD80, and CD86 expression and reduces allogeneic T cell responses: relevance to systemic vasculitis.

OBJECTIVE: There is a breakdown of tolerance to neutrophil components during systemic vasculitis, which is marked by autoantibodies and T cells with specificity for proteinase 3 or myeloperoxidase, expressed on the surface of apoptotic neutrophils. This study was undertaken to investigate the effects of human apoptotic and necrotic neutrophils on human dendritic cell (DC) phenotype and ability to stimulate allogeneic T cell proliferation. METHODS: DCs were generated from human peripheral blood mononuclear cells and allowed to interact with human apoptotic and necrotic neutrophils in the presence or absence of tumor necrosis factor alpha (TNFalpha). Effects on DC phenotype and ability to stimulate T cell proliferation were observed. RESULTS: Immature DCs engulfed apoptotic and necrotic neutrophils, resulting in up-regulation of CD83 and class II major histocompatibility complex molecules, but down-regulation of CD40, CD80, and CD86, and a decreased ability to stimulate T cell proliferation. When TNFalpha was added in combination with apoptotic neutrophils, the inhibitory effects were overcome to some extent. CONCLUSION: Our results suggest that DC uptake of apoptotic or necrotic neutrophils alone does not shift the immune response from tolerance to autoimmunity in systemic vasculitis. However, cytokines found at sites of inflammation in vasculitis patients may act as maturation factors for DCs, and in combination with apoptotic neutrophils, may lead to an autoimmune phenotype.