Laura Jones1, Laura Tan1, Suzanne Carey-Jones2, Nathan Riddell1, Richard Davies2, Ashleigh Brownsdon3, Mark Kelson3, Rhys Williams-Thomas4, Monica Busse4, Michael M Davies5, Matt P G Morgan6,7. 1. Adult Critical Care Unit, University Hospital of Wales, Cardiff, CF14 4RQ, UK. 2. Department of Anaesthetics, University Hospital of Wales, Cardiff, UK. 3. Department of Mathematics, University of Exeter, Exeter, UK. 4. Centre for Trials Research, Cardiff University, Cardiff, UK. 5. Department of Colorectal Surgery, University Hospital of Wales, Cardiff, UK. 6. Adult Critical Care Unit, University Hospital of Wales, Cardiff, CF14 4RQ, UK. morganMP@cardiff.ac.uk. 7. Centre for Trials Research, Cardiff University, Cardiff, UK. morganMP@cardiff.ac.uk.
Abstract
BACKGROUND: Consumer wrist-worn wearable activity monitors are widely available, low cost and are able to provide a direct measurement of several markers of physical activity. Despite this, there is limited data on their use in perioperative risk prediction. We explored whether these wearables could accurately approximate metrics (anaerobic threshold, peak oxygen uptake and peak work) derived using formalised cardiopulmonary exercise testing (CPET) in patients undergoing high-risk surgery. METHODS: Patients scheduled for major elective intra-abdominal surgery and undergoing CPET were included. Physical activity levels were estimated through direct measures (step count, floors climbed and total distance travelled) obtained through continuous wear of a wrist worn activity monitor (Garmin Vivosmart HR+) for 7 days prior to surgery and self-report through completion of the short International Physical Activity Questionnaire (IPAQ). Correlations and receiver operating characteristic (ROC) curve analysis explored the relationships between parameters provided by CPET and physical activity. DEVICE SELECTION: Our choice of consumer wearable device was made to maximise feasibility outcomes for this study. The Garmin Vivosmart HR+ had the longest battery life and best waterproof characteristics of the available low-cost devices. RESULTS: Of 55 patients invited to participate, 49 (mean age 65.3 ± 13.6 years; 32 males) were enrolled; 37 provided complete wearable data for analyses and 36 patients provided full IPAQ data. Floors climbed, total steps and total travelled as measured by the wearable device all showed moderate correlation with CPET parameters of peak oxygen uptake (peak VO2) (R = 0.57 (CI 0.29-0.76), R = 0.59 (CI 0.31-0.77) and R = 0.62 (CI 0.35-0.79) respectively), anaerobic threshold (R = 0.37 (CI 0.01-0.64), R = 0.39 (CI 0.04-0.66) and R = 0.42 (CI 0.07-0.68) respectively) and peak work (R = 0.56 (CI 0.27-0.75), R = 0.48 (CI 0.17-0.70) and R = 0.50 (CI 0.2-0.72) respectively). Receiver operator curve (ROC) analysis for direct and self-reported measures of 7-day physical activity could accurately approximate the ventilatory equivalent for carbon dioxide (VE/VCO2) and the anaerobic threshold. The area under these curves was 0.89 for VE/VCO2 and 0.91 for the anaerobic threshold. For peak VO2 and peak work, models fitted using just the wearable data were 0.93 for peak VO2 and 1.00 for peak work. CONCLUSIONS: Data recorded by the wearable device was able to consistently approximate CPET results, both with and without the addition of patient reported activity measures via IPAQ scores. This highlights the potential utility of wearable devices in formal assessment of physical functioning and suggests they could play a larger role in pre-operative risk assessment. ETHICS: This study entitled "uSing wearable TEchnology to Predict perioperative high-riSk patient outcomes (STEPS)" gained favourable ethical opinion on 24 January 2017 from the Welsh Research Ethics Committee 3 reference number 17/WA/0006. It was registered on ClinicalTrials.gov with identifier NCT03328039.
BACKGROUND: Consumer wrist-worn wearable activity monitors are widely available, low cost and are able to provide a direct measurement of several markers of physical activity. Despite this, there is limited data on their use in perioperative risk prediction. We explored whether these wearables could accurately approximate metrics (anaerobic threshold, peak oxygen uptake and peak work) derived using formalised cardiopulmonary exercise testing (CPET) in patients undergoing high-risk surgery. METHODS: Patients scheduled for major elective intra-abdominal surgery and undergoing CPET were included. Physical activity levels were estimated through direct measures (step count, floors climbed and total distance travelled) obtained through continuous wear of a wrist worn activity monitor (Garmin Vivosmart HR+) for 7 days prior to surgery and self-report through completion of the short International Physical Activity Questionnaire (IPAQ). Correlations and receiver operating characteristic (ROC) curve analysis explored the relationships between parameters provided by CPET and physical activity. DEVICE SELECTION: Our choice of consumer wearable device was made to maximise feasibility outcomes for this study. The Garmin Vivosmart HR+ had the longest battery life and best waterproof characteristics of the available low-cost devices. RESULTS: Of 55 patients invited to participate, 49 (mean age 65.3 ± 13.6 years; 32 males) were enrolled; 37 provided complete wearable data for analyses and 36 patients provided full IPAQ data. Floors climbed, total steps and total travelled as measured by the wearable device all showed moderate correlation with CPET parameters of peak oxygen uptake (peak VO2) (R = 0.57 (CI 0.29-0.76), R = 0.59 (CI 0.31-0.77) and R = 0.62 (CI 0.35-0.79) respectively), anaerobic threshold (R = 0.37 (CI 0.01-0.64), R = 0.39 (CI 0.04-0.66) and R = 0.42 (CI 0.07-0.68) respectively) and peak work (R = 0.56 (CI 0.27-0.75), R = 0.48 (CI 0.17-0.70) and R = 0.50 (CI 0.2-0.72) respectively). Receiver operator curve (ROC) analysis for direct and self-reported measures of 7-day physical activity could accurately approximate the ventilatory equivalent for carbon dioxide (VE/VCO2) and the anaerobic threshold. The area under these curves was 0.89 for VE/VCO2 and 0.91 for the anaerobic threshold. For peak VO2 and peak work, models fitted using just the wearable data were 0.93 for peak VO2 and 1.00 for peak work. CONCLUSIONS: Data recorded by the wearable device was able to consistently approximate CPET results, both with and without the addition of patient reported activity measures via IPAQ scores. This highlights the potential utility of wearable devices in formal assessment of physical functioning and suggests they could play a larger role in pre-operative risk assessment. ETHICS: This study entitled "uSing wearable TEchnology to Predict perioperative high-riSk patient outcomes (STEPS)" gained favourable ethical opinion on 24 January 2017 from the Welsh Research Ethics Committee 3 reference number 17/WA/0006. It was registered on ClinicalTrials.gov with identifier NCT03328039.
Authors: D Z H Levett; S Jack; M Swart; J Carlisle; J Wilson; C Snowden; M Riley; G Danjoux; S A Ward; P Older; M P W Grocott Journal: Br J Anaesth Date: 2017-11-24 Impact factor: 9.166
Authors: Anna Shcherbina; C Mikael Mattsson; Daryl Waggott; Heidi Salisbury; Jeffrey W Christle; Trevor Hastie; Matthew T Wheeler; Euan A Ashley Journal: J Pers Med Date: 2017-05-24