Abstract TP166: The Six Minute Walk Test as a Predictor for Fall Risk in Persons With Stroke

Abstract

Introduction: Persons with stroke have increased risk for recurrent stroke, other chronic health conditions and falls. One option to reduce the risk of worsening health conditions is to increase physical activity by engaging in group medical fitness programs like cardiac rehabilitation (CR). CR programs utilize clinical measures for functional capacity, commonly exercise stress testing or the six-minute-walk test (6MWT). Absent is measurement and focus on balance or balance confidence. Supervising staff may be unaware of fall risk which is an important safety factor for persons with stroke. The purpose of this study was to determine the degree to which the 6MWT is associated with fall risk in community-dwelling persons with stroke. Methods: A cross-sectional analysis measured association between the 6MWT and fall risk in 66 persons with stroke. Fall risk is defined as a score on the Activities Balance Confidence Scale (ABC) of < 81.1 based on a study by Beninato et al. (2009) which found significant accuracy of fall prediction with this cutoff (Sensitivity = 1.00, Specificity = 0.72(0.51-0.93)). The 6MWT and the 6MWT combined with other data differing between fall risk groups (e.g. walking speed, Berg Balance Scale and time since stroke) were evaluated using univariate logistic regression to determine influence on fall risk. The best fit model was used in Receiver Operating Characteristic (ROC) analysis to determine the area under the curve (AUC) to detect an increased risk of falls. Likelihood ratios and post-test probabilities were calculated. Results: The 6MWT was associated with fall risk in logistic regression (p=0.002) with an odds ratio (OR) of 0.995 (0.991,0.999), p=0.007). The AUC for the univariate 6MWT ROC model (best fit) was 0.701 (p=0.006). The cutoff for increased fall risk was 6MWT < 331.65 meters. The post-test probability of fall risk was 74.3%, increased from a pre-test probability of 59.1%. Conclusion: The association between fall risk and 6MWT suggests that in addition to aerobic capacity and motor components, the 6MWT includes a fall risk/balance confidence component. In conclusion, utilizing the 6MWT to screen fall risk in CR and other community exercise programs can enhance safety for persons with stroke without additional testing burden.