JMIR Publications

ABSTRACT

Background:

Measurement of free-living gait using wearable devices may offer higher granularity and temporal resolution than current clinical assessments for patients with Parkinson’s disease (PD). However, increasing the number of devices worn on the body adds patient burden and impacts compliance.

Objective:

We investigated the impact of reducing the number of wearable devices on the ability to assess of gait impairments in patients with PD.

Methods:

35 PD and 60 healthy volunteers (HV) performed a gait task during two clinic visits. PD participants were assessed in the ON and OFF medication state using the Movement Disorder Society-sponsored revision of the Unified Parkinson’s Disease Rating Scale (MDS-UPDRS). Gait features derived from a single lumbar-mounted accelerometer were compared with those derived using 3 and 6 wearable devices for both PD and HV participants.

Results:

Comparable performance was observed for predicting the MDS-UPDRS gait score using longitudinal mixed-effects models fit with gait features derived from one, 3, and 6 devices (single device: RMSE = 0.64, R2 = 0.53; 3 devices: RMSE = 0.64, R2 = 0.54; 6 devices: RMSE = 0.54, R2 = 0.65). In addition, MDS-UPDRS gait scores predicted using all 3 models were significantly different between ON and OFF motor states.

Conclusions:

We observed marginal benefit of using multiple devices for assessing gait impairments in patients with PD when compared with gait features derived using a single lumbar-mounted accelerometer. The wearability burden associated with the use of multiple devices should offset gains in accuracy for monitoring gait under free-living conditions.