Longitudinal assessment of falls in patients with Parkinson’s disease using inertial sensors and the Timed Up and Go test

Objective: To examine the predictive validity of a TUG test for falls risk, quantified using body-worn sensors (QTUG) in people with Parkinsons Disease (PD). We also sought to examine the inter-session reliability of QTUG sensor measures and their association with the Unified Parkinsons Disease Rating Scale (UPDRS) motor score. Approach: A six-month longitudinal study of 15 patients with Parkinsons disease. Participants were asked to complete a weekly diary recording any falls activity for six months following baseline assessment. Participants were assessed monthly, using a Timed Up and Go test, quantified using body-worn sensors, placed on each leg below the knee. Main results: The results suggest that the QTUG falls risk estimate recorded at baseline is 73.33% (44.90, 92.21)accurate in predicting falls within 90 days, while the Timed Up and Go time at baseline was 46.67% (21.27, 73.41)accurate. The Timed Up and Go time and QTUG falls risk estimate were strongly correlated with UPDRS motor score. Fifty-two of 59 inertial sensor parameters exhibited excellent inter-session reliability, five exhibited moderate reliability, while two parameters exhibited poor reliability. Significance: The results suggest that QTUG is a reliable tool for the assessment of gait and mobility in Parkinsons disease and, furthermore, that it may have utility in predicting falls in patients with Parkinsons disease.Insight Research CentreCare Innovations LL