This Letter aims to create a fuzzy logic-based assistive prevention tool for falls, based on accessible sensory technology, such as smartwatch, resulting in monitoring of the risk factors of falls caused by orthostatic hypotension (OH); a drop in systolic blood pressure (DSBP) >20 mmHg due to postural changes. Epidemiological studies have shown that OH is a high risk factor for falls and has a strong impact in quality of life (QoL) of the elderly's, especially for some cases such as Parkinsonians. Based on smartwatch data, it is explored here how statistical features of heart rate variability (HRV) can lead to DSBP prediction and estimation of the risk of fall. In this vein, a pilot study was conducted in collaboration with five Greek Parkinson's Foundation patients and ten healthy volunteers. Taking into consideration, the estimated DSBP and additional statistics of the user's medical/behavioural history, a fuzzy logic inference system was developed, to estimate the instantaneous risk of fall. The latter is fed back to the user with a mechanism chosen by him/her (i.e. vibration and/or sound), to prevent a possible fall, and also sent to the attentive carers and/or healthcare professionals for a home-based monitoring beyond the clinic. The proposed approach paves the way for effective exploitation of the contribution of smartwatch data, such as HRV, in the sustain of QoL in everyday living activities.
Introduction:The exploitation of internet of things (IoT) as an infrastructure for creating assistive technology solutions is a necessity to healthcare self-management systems. This would lead to improvement of the quality of life (QoL) standards, due to the proactively management of the risks that progressive diseases can cause, such as Parkinson's disease (PD). PD patients face the risk of fall, frailty and depression daily. An unobtrusive approach to reduce the risk of fall in PD patients by using non-invasive wearable technology is crucial in maintaining their QoL. The biometric data acquired by wearable technology can reveal statistical characteristics from user's interaction and mine useful information about the user's physiology. To prevent falls, a prediction model could be developed estimating the risk of falls, based on orthostatic hypotension (OH) episodes in PD, capturing unobtrusively biometric data through a smartwatch. Neurogenic OH is affecting up to 60% of the PD's patients, and the multidimensionality of the disease creates an increased risk in PD patients. On the later stages of the disease, up to 20% of the PD patients face symptomatic OH [1,2]. In addition to PD, up to 40% of the elderly adults >65 years old experience an indoor fall each year, which decreases the mobility and self-confidence. The cost of fall-related injuries has been reported $19 billion for a year [3].In this work, an innovative risk of fall estimation (RFE) system is introduced as a healthcare assistive self-management tool based on a smartwatch. A pilot study was conducted with ten controls and five PD patients applying a ...