http://www.diva-portal.org
Postprint
This is the accepted version of a paper presented at Twentieth International Congress of Parkinson's
Disease and Movement Disorders, Berlin, Germany, June 19-23, 2016.
Citation for the original published paper:
Memedi, M., Thomas, I., Nyholm, D., Westin, J., Senek, M. et al. (2016)
Construction of levodopa-response index from wearable sensors forquantifying Parkinson's disease motor functions.
In: Twentieth International Congress of Parkinson's Disease and Movement Disorders
N.B. When citing this work, cite the original published paper.
Permanent link to this version:
Objective
Results
Conclusions
Construction of levodopa‐response index from wearable sensors for
quantifying Parkinson's disease motor functions
Mevludin Memedi 96E6 Vlias Thomas96 jag Nyholm U6 +erker Westin 96 Marina Senek U6 Somayeh 'ghanavesi 96 'lexander Medvedev f6 ‘åkan 'skmark U6 StenOMagnus 'quilonius U6 zilip ±ergquist Ö6 Radu ’onstantinescu b6 zredrik Ohlsson .6 +ack Spira P6 Sara Lycke G6 and 'nders –ricsson .
9 ’omputer –ngineering6 jalarna University6 E Vnformatics6 School of ±usiness6 Örebro University6 U Neuroscience6 Neurology6 Uppsala University6 f Vnformation Technology6 Uppsala University6 Ö jept7 of Pharmacology6 University of =othenburg6 b jept7 of ’linical Neuroscience6 University of =othenburg6 . 'creo Swedish V’T6 P Sensidose '±6 G ’envigo '±
The S±LRV was strongly correlated to mean TRS with a Pearson correlation coefficient of L7.G 5’Vw L7.fOL7PU6 p(L7LL9R7 The GÖF confidence interval for the mean squared error of S±LRV on patientsB data was ± 97bE with a mean value of L7Ö. whereas on healthy controls data was ± 9 with a mean value of L7E.7 The sensorObased spatiotemporal parameters had good internal consistency with a ’ronbach’s 'lpha coefficient of L7P. and significantly differed between patients and healthy controls7 zigure E shows four graphs of S±LRV and mean TRS for four patients7
Methods
zigure 97 Subject wearing a wrist motion sensor while performing rapid alternating movements of hands7 The subjects performed the tests first with the right hand and then with the left hand and each test lasted for EL seconds7
zigure E7 zour representative cases of patients with
superimposed mean TRS and S±LRV scores over time7 TRS – Treatment Response Scale6 S±LRV – sensorO based levodopa response index7
Data collection
Data processing and analysis
Sensor measurements during rapid alternating movements of hands 5zigure 9R were processed with time series analysis methods to calculate spatiotemporal parameters designed to measure bradykinesia and dyskinesia7 zor each hand6 Gb spatiotemporal parameters were calculated and their average scores were then used in a principal component analysis to reduce the dimensionality by retaining b principal components7 These components were then used as predictors to support vector machines and to be mapped to the mean TRS ratings of the three specialists and to calculate the S±LRV7 zor this analysis6 a 9LOfold stratified crossOvalidation was performed7
The goal of this study was to investigate the feasibility of wrist worn motion sensors to objectively measure motor functions in Parkinson’s disease 5PjR7 More specifically6 the aim was to construct a sensorObased levodopaOresponse index 5S±LRVR and evaluate its clinimetric properties 5convergent validity and internal consistencyR7
Nineteen advanced Pj patients and EE healthy controls were recruited in a single center6 open label6 single dose clinical trial in Sweden7 The subjects performed standardized motor tasks while wearing one sensor on each wrist and one on each ankle7 –ach sensor unit consisted of threeOdimensional accelerometer and gyroscope7 The patients were video recorded and the videos were blindly rated by three independent movement disorder specialists7 The clinical scores were given using the Treatment Response Scale 5TRSR on a scale from OU : ‘Very Off’ to L : ‘On’ to cU : ‘Very dyskinetic’7 The clinical assessments were based on the overall motor function of the patients7 ' mean TRS was defined as the mean of the three specialists’ assessments per time point7 The measurements were repeated over several time points following a single levodopa8carbidopa morning dose 5ÖLF over normal to induce dyskinesiasR7
The results demonstrated that the S±LRV had good clinimetric properties for measuring motor functions 5Off and dyskinesiaR in Pj patients7 The method could also distinguish hand rotation movements exhibited by patients from those exhibited by healthy controls7 The S±LRV provides effectOtime profiles6 which could be useful during therapy individualization of advanced Pj patients7
