The emergence of wearable biosensors might be fantastic for tracking the cardiovascular health of individual patients, but it raises questions of reliability of the data as well as ethical issues.
Tracking the movements of patients’ hearts has become commonplace with the advent of small, wearable cardiovascular biosensors. Improvements in flexible sensors, better algorithms and improved mobile cellular technology have all meant that pocket sized or smaller machines can provide a reliable measurement of both rate and rhythm of the heartbeat.
While this is not quite as comprehensive as a 10-electrode view of the heart that hospital echocardiographs provide, portable sensors can monitor patients 24/7 at home or as they go about their daily lives, which has enormous potential advantages in terms of lowered hospital costs and reduced inconvenience to the patient.
A number of devices are now available that have been designed specifically to allow doctors immediate and remote access patients’ heart rates and rhythms.
- Intelesen’s zensor, recently cleared by the U.S. Food and Drug Administration (FDA) provides seven-day ECG and cardiac event monitoring. It can detect a variety of arrhythmias, immediately notifying the monitoring physician. Data from the zensor is transmitted to a secure server, where it can be accessed by the appropriate healthcare professionals with the goal of preventing stroke and managing atrial fibrillation and syncope.
- Medtronic have developed Seeq, a Mobile Cardiac Telemetry (MCT) system that includes a sticking sensor and a wireless transmitter. Seeq is designed for cardiac patients with frequent symptoms and provides monitoring for up to 30 days. In this case, the data is transmitted to a diagnostic testing facility where trained technicians review the data and notify the monitoring physicians in case of cardiovascular events.
- Zephyr Technology Corporation, now also owned by Medtronic, have a similar BioPatch. This is wireless sensor connected to disposable ECG electrodes. BioPatch continuously monitors heart rate, respiration rate, ECG and activity levels, as well as position and posture. BioPatch data can be accessed via a dedicated web portal.
Fitness Trackers Provide Heart Data
As sensors have developed, even consumer fitness trackers can provide some insight into cardiovascular health. For example, in addition to measuring physical activity, the wrist-worn fitbit blaze measures heart rate, as does the Angel Sensor, in addition to recording skin temperature.
If treating doctors can reliably and ethically access their data, such devices may have an expanding role in cardiovascular medicine. There has already been an anecdotal report of a patient presenting with a seizure and by accessing his fitbit data, the doctors could determine whether he had a pre-existing heart condition or whether the arrhythmia was acute, which is crucial for determining appropriate treatment.
All these cardiovascular data points, coming from not only patients but also consumers represent a potential bonanza for medical researchers, but making sense of that data is not without considerable challenges for the very reason wearable sensors are popular with consumers: because they can decide how, when, where and under what conditions to wear them, which obviously has implications for the reliability of the data.
Dr. Kuniharu Takei, from the Department of Physics and Electronics at Osaka Prefecture University, cautioned: “As the first step to utilize the wearable sensors, I would like to recommend that users or practitioners only monitor trends in health changes and not diagnostic results. The reliability of diagnostic results is still under consideration because they strongly depend on how the device was attached to the person, as well as other factors, such as the activity, weather, etc.”
Questions of Data Privacy and Data Protection
The ethical issues with wearable sensors are essentially questions of informed consent, where patients know what their data will be used for, and questions of data privacy and data protection. As Yasser Khan, researcher in wearable medical devices at UC Berkeley said, “Anonymizing the raw data and adding a layer of encryption should be standard practice. Most research labs do that already. But patients should make sure that these privacy and security checks are in place.”
Anonymizing the raw data and adding a layer of encryption should be standard practice. Most research labs do that already.
This is not to say that researchers aren’t enthusiastic about the prospects, quite the contrary. For Dr. Takei, the next generation of wearable devices has considerable potential for diagnosis and disease prediction, providing the data can be readily accessed from the cloud, is anonymous, and is sourced from a very large, very diverse population. In his opinion, the way to achieve this is by developing flexible, low-cost, disposable sensors that can be worn comfortably, like bandages, even during sleep.
While for Yasser Khan, “Wearable devices will play a pivotal role in shifting healthcare from hospitals to homes. In-home healthcare will free up resources for providing proper care to the aging world population. The research community have already identified the types of devices needed for in-home health monitoring. Clinical studies are a good starting point for determining the promise and capability of the wearable medical devices.”