Measurement of vital signs such as temperature, heart rate and the electrical properties of skin with a wearable device can be used to predict clinical laboratory results.
The routine measurement of parameters such as body temperature, heart and respiration rate, although non-specific, are of value in the overall assessment of a patient’s general wellbeing. In addition to the assessment of physical signs, further information can be gathered from laboratory analysis of blood or urine. However, all of these evaluations require that the person attends a clinic appointment. In recent years, the development of wearable technology has enabled the measurement of some vital signs such as heart rate and temperature but there has been limited research into the value of this longitudinally collected data. Nevertheless, it is possible that wearable technology has the potential to provide useful data for managing health conditions. But in order to fully utilise the data captured by wearable devices, it is necessary to determine whether these data are able to accurately mirror the results obtained in a clinic. This was the idea behind a study by a team from the Department of Genetics, Stanford University, US, which set out to determine if the vital signs collected from a wearable device (wVS) could be used as a non-invasive proxy measurement of clinical laboratory data using models of the relationship between wVS and clinical labs.
A total of 54 participants with a mean age of 56 years (44% male) were monitored for an average of 3.3 years. The wearable device measured heart rate, skin temperature, accelerometery and electrodermal activity (EDA). This latter measurement of the electrical properties of the skin, can assess skin hydration. Using heart rate, the researchers found that the wVS recordings was identical to the clinic-based measurements (both 71 beats per minute). Using machine learning models, the researchers extended their work and observed a high correlation between changes in wVS data and haematocrit, red blood cell count, haemoglobin and platelet count. For example, a higher body temperature and lower levels of movement (as assessed by accelerometery) tended to indicate illness, which matched up with a higher white blood cell count.
Commenting on their findings, the authors suggested that the continuous data collected by a wVS could be used to detect deviations from normal and thus serve as a means of identifying the need for further clinical laboratory evaluation. Although more work needs to be done, these initial results suggest that wearable devices have the potential to assess clinical parameters that, at present, can only be measured in laboratories.
Dunn J et al. Wearable sensors enable personalised predictions of clinical laboratory measurements. Nat Med 2021