Non-motor correlates of wrist-worn wearable sensor use in Parkinson's disease: an exploratory analysis.

Wearable sensors are becoming increasingly more available in Parkinson's disease and are used to measure motor function. Whether non-motor symptoms (NMS) can also be measured with these wearable sensors remains unclear. We therefore performed a retrospective, exploratory, analysis of 108 patients with a diagnosis of idiopathic Parkinson's disease enroled in the Non-motor Longitudinal International Study (UKCRN No. 10084) at King's College Hospital, London, to determine the association between the range and nature of NMS and an accelerometer-based outcome measure of bradykinesia (BKS) and dyskinesia (DKS). NMS were assessed by the validated NMS Scale, and included, e.g., cognition, mood and sleep, and gastrointestinal, urinary and sexual problems. Multiple linear regression modelling was used to identify NMS associated with BKS and DKS. We found that BKS was associated with domains 6 (gastrointestinal tract;  = 0.006) and 8 (sexual function;  = 0.003) of the NMS scale. DKS was associated with domains 3 (mood/cognition;  = 0.016), 4 (perceptual problems;  = 0.025), 6 (gastrointestinal tract;  = 0.029) and 9 (miscellaneous,  = 0.003). In the separate domains, constipation was significantly associated with BKS. Delusions, dysphagia, hyposmia, weight change and hyperhidrosis were identified as significantly associated with DKS. None of the NMSS domains were associated with disease duration ( ≥ 0.08). In conclusion, measures of BKS and DKS were mainly associated with gastrointestinal problems, independent of disease duration, showing the potential for wearable devices to pick up on these symptoms. These exploratory results deserve further exploration, and more research on this topic in the form of comprehensive large-scale studies is needed.