Activity monitoring by wearable device use in chronic disease management
Given what is known about the importance of tracking physical activity in the management of patients with chronic diseases, how can the current wave of consumer-accessible wearable technologies make the transition from personal wellness tools to patient-friendly clinical tools? A recent Pew Internet and American Life survey found that 69% of US adults track weight, diet, symptoms, or health routines in some manner [
1]. Technological progress has fostered the development of a variety of ‘wearable’ devices and sensors for self-tracking health, including activity trackers, smart watches, smart clothing, patches and tattoos, ingestibles, and smart implants [
2]. Historically, validated medical devices embedded with sensors have been applied in clinical trials and targeted research studies conducted in medical settings; however, advances in technology in activity (e.g., steps), physiological (e.g., blood oxygen saturation), and biochemical (e.g., pH) measurement have supported patient care and research outside of hospitals [
3].
Currently, the most popular consumer-accessible wearable devices, e.g., Fitbit® and JawboneUP®, measure movements through accelerometers that apply algorithms to estimate activity levels (usually in the form of steps taken), sleep quality, and calories expended. Further, these wearable devices improve upon traditional pedometers as they include a number of additional behavior change techniques such as goal-setting, social support, social comparison, and rewards [
4]. An Internet survey found that about 10% of Americans 18 years and over report ownership of a modern activity tracker such as a Fitbit® or JawboneUP® [
5]. These wearable devices have been adopted by individuals seeking to enhance their personal fitness through increased personal health surveillance and social connections with others using the devices. Although the use of technology is often considered to be driven by younger age groups, the uptake of wearable devices is bimodally distributed – younger (25- to 34-year-old) groups use them for fitness enhancement, while older (55- to 64-year-old) groups use them to improve overall health [
5]. Studies have shown the utility of activity monitoring in ostensibly healthy elderly or adult populations [
6].
Can the use wearable devices lead to positive health impacts in chronic disease populations? There is some evidence to support this hypothesis. People with more serious health problems are more likely to report benefits as a result of tracking their health [
1]. Activity monitors, with their ability to capture walking behavior in the real-world environment, may enable providers and patients to gain insights into the progression and impact of illnesses [
7]. Further, as the population ages, there is increasing emphasis on reducing hospital stays, decrease readmission rates, and help patients manage their conditions in their home environments. Perhaps activity monitoring can be an effective tool in such disease self-management programs.
Available studies have primarily focused on establishing the feasibility of measuring activity and associating activity levels with beneficial outcomes. Activity-monitoring devices that record free-living walking behavior may be helpful in quantifying levels of ambulation and provide insights into important symptoms such as fatigue in multiple sclerosis patients [
7,
8]. The first study investigating the use of a modern wearable activity tracker on post-surgical mobility recovery during hospitalization was recently published by the Mayo Clinic [
9]. This study found a significant relationship between the early recovery step count, hospital length of stay, and dismissal disposition in a group of elderly cardiac surgery patients. The use of accelerometers and pedometers to measure physical activity has also enhanced treatment for individuals participating in pulmonary rehabilitation [
10]. A recent meta-analysis of activity monitor-based counseling studies with diabetes patients concluded that activity monitor-based counseling had a beneficial effect on physical activity, blood glucose, systolic blood pressure, and body mass index [
11]. However, there is a lack of evidence demonstrating the effectiveness of activity monitors in chronic disease (e.g., osteoarthritis, cardiovascular diseases, type 2 diabetes mellitus, and chronic obstructive pulmonary disease) [
12]. Studies have found modest short-term activity improvements and weight loss resulting from monitor and pedometer use [
13-
15], but it is not clear that these results are sustained over extended periods.
Self-management technology and physiological measurement have expanded beyond hospital settings to remote and direct use by patients with chronic diseases [
16], but the adoption and utility of wearable devices for activity tracking is not well understood. Patients with chronic health conditions struggle with multifaceted needs that change during the course of their disease journeys. One path to success with wearable devices may reside in patient-driven health care, which encourages greater patient-physician collaboration, expanded patient social networks, and increased patient use of personal data for tracking their health outcomes [
17]. In order to realize widespread adoption in a real-world community of chronic disease patients, key patient-centered questions need to be addressed, namely i) is the data useful in care? ii) how can users stay motivated to use devices? iii) does usage lead to behavior change and affect health outcomes? iv) is the information safe and will privacy be maintained? and v) will providers use this information in treatment planning and delivery? The promise of wearables will not be realized if they simply offer data – they must offer insights, outcomes, and engagement [
18].