About 1 in 5 US adults regularly wear a smart watch or fitness tracker, according to a recent survey from Pew Research Center.1 During the pandemic, global shipments of smartwatches soared by 47%.2 Rapid technology development coupled with growing evidence supporting regular physical activity for health has spurred this interest in wearable, fitness-focused technologies among the general population, people with cancer, and the clinicians who treat them.
“My thought as commercial devices became so prevalent was there could be valuable information that people are currently using for fitness purposes that could also be valuable for clinical care of cancer patients at risk for being inactive due to their comorbidities, their cancer, and their cancer treatments,” says Nitin Ohri, MD, MS, attending physician at Montefiore Medical Center and associate professor at Albert Einstein College of Medicine in the Department of Radiation Oncology, in Bronx, NY.
Armin Shahrokni, MD, MPH, associate attending in oncology and geriatrics at Memorial Sloan Kettering Cancer Center in New York City, concurs, noting that advances in digital technology and digital health tools, in general, have paved the way for new patient management strategies in cancer care. “With wearables, we now have the opportunity to go beyond what’s happening in the clinic and hospital and dig deeper into why patients do worse or better in treatment,” he says.
While wearables have not fully penetrated routine radiation oncology practice, the technology could help usher in a new era of care delivery that’s less fragmented and more data-driven.
Research on Activity and Wearables
In the context of monitoring radiation therapy treatment effects, toxicities vary significantly among patients, disease sites, and doses. Most commonly, patients experience fatigue,3 a side effect that clinicians must consider over the course of treatment due to the potential negative impact of decreased activity levels on outcomes. For several common cancers, evidence supports significant reductions for mortality with high vs low levels of physical activity.4 Studies also show an association between increased physical activity and reduced cancer risk,4 supporting the prevention of cancer through lifestyle change. The US Department of Health and Human Services 2018 Physical Activity Guidelines Advisory Committee (PAGAC) suggests that all individuals should be encouraged to engage in recommended levels of physical activity to both reduce cancer risk and improve cancer prognosis.5
In recent years, small studies across a variety of cancer populations support the feasibility and potential clinical value of mobile sensors in oncology.6 Changes in biomarkers – captured by digital sensors – may reflect meaningful variation in functional status, symptom burden, quality of life, and risk for adverse clinical outcomes.5
“Over the past 5 to 6 years, things have improved significantly in the reliability and validity of these [wearable] tools,” Dr. Shahrokni reports. “We have large using wearables such as Apple Watch and Fitbit in cancer patients, correlating objective functional assessments of patient symptoms with overall quality of life and well-being.”7,8
This suggests an opportunity to enable real-time remote monitoring of patients for more proactive, comprehensive, and personalized cancer care, adds Liao Yue, PhD, MPH, CPH, assistant professor of public health and director of the Physical Activity and Wearable Sensors Lab at the University of Texas (UT) Arlington.
“When people come into the clinic, we only know a snapshot – one moment in time. With sensor monitoring, we can have a better sense of how they are doing overall. This supplementary data is very helpful for us to consider in adjusting a treatment plan to make it more personalized,” says Dr. Liao, who’s also a fellow of the National Cancer Institute’s Transdisciplinary Research on Energetics and Cancer.
Dr. Ohri, who ran one of the first clinical trials using wearables to monitor patients receiving radiation therapy with concurrent chemotherapy, reports that pilot data about basic activity was highly informative.9 “Step counts were far more predictive of hospitalization events and, in some cases, survival outcomes, when compared to standard measures such as performance status and disease stage,” he says.
A Sense for Sensors
For his wearable device trials, Dr. Ohri has most often used a user-friendly, commercial device that does not require charging. In other studies, clinicians obtain data using research-grade devices or consumer-facing fitness wearables like Fitbit, Apple Watch, or Whoop that track activity with impressive accuracy in the form of steps per day, recorded workouts, and/or periods of elevated heart rate with movement.
“For the most part, consumer-facing devices have really good usability, and patient compliance is typically higher than for research-grade sensors,” Dr. Liao says, noting that the latter do not often display output for the wearers, which can deter user engagement.
The biggest benefit of wearables, Dr. Liao says, is the objectivity they provide regarding activity levels throughout treatment courses.
“When we ask, ‘How do you feel?’ or ‘How did you feel last week?’ we are relying on a patient’s recall or feelings. It turns out it’s hard to remember very well,” Dr. Liao says. “With sensor technology, we can see whether their activity levels are consistent, and with a better understanding of those patterns, we can ask for more information and get a more holistic picture of our patients.”
Dr. Shahrokni explains that in the radiation oncology setting, functional performance status is one of the most important parameters for deciding when and how to treat the patient. “Fortunately, it’s easy to capture who’s a frail or wheelchair-bound patient and who is a marathon runner, but there are a lot of people in that gray zone, and we don’t really know how active they are,” he says. Plus, subjective reporting is a factor. “The patient tells me ‘I’m very active,’ and the wife in the background says, ‘He’s just sleeping.’”
It is critical to measure activity functions of cancer patients objectively and continuously over time, including sleep quality and activity levels, Dr. Shahrokni says. “Without good sleep, their energy level is going to go down and they get fatigued, then they won’t be as active as they should be. That will impact the [physician’s] decisions about how to treat that patient. With sensors, we know more, and hopefully we are better able to serve our patients.”
A comprehensive, holistic patient view enables radiation oncologists to enhance care in patient evaluation before treatment, monitoring during treatment, and surveillance in the survivorship period, Dr. Ohri says. When considering treatment options, much is left to physician and patient discretion as it relates to patient fitness. “These decisions are somewhat based on objective measures like lab tests and pulmonary functions and other objective physiologic parameters, but wearables could go a long way in helping us identify which patients are more fit than others and which ones should be treated more aggressively vs with a less intense treatment.”
During tailored treatment, activity metrics could reveal whether a patient is at risk for an adverse event, potentially allowing for clinician intervention or direct encouragement to change behavior to improve health. From a population health perspective, data from wearables could also help physicians compare the impact of treatments on patient function. In the survivorship or post-treatment setting, “activity is a powerful predictor of all-cause mortality,” Dr. Ohri says, adding, “Encouraging an active, healthy lifestyle is critical.”
Challenges and Future Directions
While data from wearables offers new opportunities, there are numerous challenges to overcome for widespread clinical use in radiation therapy and health care at large. Consumer-facing wearables do not yield “ready-to-use” data for clinicians, but instead are designed to engage users and encourage app usage. While radiation oncologists gain insight from the output, what to do with the data and ownership of it is less clear, Dr. Liao says.
“How can we translate the data to more useful information and then tailor that to the patient?” she poses. Determining this will help remote patient monitoring reach its potential.
“We still need to work on privacy, security, and data confidentiality, adds Dr. Shahrokni. Things need to be ironed out on both the access side of getting data to the EMR [electronic medical record] and then the physician action based on that information.” An optimal workflow will likely involve automation with layers of human intervention. Patients want to share their data with their treating physicians to receive better care, he says, and are already initiating discussions by showing activity tracker data.
“Patients’ reception to such solutions will be very high, which it should be if we are closing the loop on not only implementing wearable solutions in research and routine care, but also in interpreting the data and providing support,” he says.
Integrating wearable data into the EMR will further help clinicians operationalize the data in clinical care. The field needs more research to motivate health systems and insurers to invest fully in wearable technologies, says Dr. Liao. “As researchers, we really need to demonstrate how using sensors will provide a return on investment. We need to produce evidence that they are really cost effective.”
Consumer-facing smartwatches and fitness trackers can be expensive, and many radiation therapy patients lack the resources to purchase them and enable their use via smartphones. “While these devices are incredibly promising for bringing new dimensions of data to our clinical workflow, if not implemented correctly, they could also exacerbate the digital divide,10 leaving some patients behind,” Dr. Ohri says.
Dr. Ohri and his team are working on a number of trials including one to determine if patients who have been given a pedometer that’s monitored and analyzed using artificial intelligence will receive more prompt and effective supportive care from their clinicians to reduce ER visits and hospitalizations during a chemoradiation treatment course for lung cancer. He’s also using wearables in therapeutic trials to objectively compare toxicities of different treatment approaches.
“The technology is becoming so ubiquitous, it would be silly not to try to use it to improve our patient outcomes,” he says.
Dr. Shahrokni agrees. “If patients are willing to wear [devices], it’s on us to collect the data and find out how important it is,” he says. Health care thought leaders, institutions, and vendors need to collaborate to improve care and incorporate the technology seamlessly into radiation therapy.
“Technology, in itself, is not a goal; technology is a tool,” Dr. Shahrokni says. “The goal is to provide better care for the patient with a technology that is useful.”
1. Vogels EA. About one-in-five Americans use a smart watch or fitness tracker. Pew Research Center. January 9, 2020. Accessed May 10, 2022. https://www.pewresearch.org/fact-tank/2020/01/09/about-one-in-five-americans-use-a-smart-watch-or-fitness-tracker/
2. Eadicicco L. Fitness trackers are getting more personal, powerful in 2022 and beyond. CNET. January 29, 2022. Accessed May 10, 2022. https://www.cnet.com/tech/mobile/fitness-trackers-are-getting-more-personal-powerful-in-2022-and-beyond/
3. Radiation Therapy Side Effects. National Cancer Institute. Reviewed: January 11, 2022. Accessed May 10, 2022. https://www.cancer.gov/about-cancer/treatment/types/radiation-therapy/side-effects
4. McTiernan A, Friedenreich C, Katzmarzyk P. Physical activity in cancer prevention and survival: a systematic review. medicine & science in sports & exercise. June 2019. Accessed May 10, 2022. https://journals.lww.com/acsm-msse/Fulltext/2019/06000/Physical_Activity_in_Cancer_Prevention_and.20.aspx
5. 2018 Physical Activity Guidelines Advisory Committee. 2018 Physical Activity Guidelines Advisory Committee Scientific Report. Washington, DC: US Department of Health and Human Services, 2018. Accessed May 10, 2022. https://health.gov/sites/default/files/2019-09/PAG_Advisory_Committee_Report.pdf
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8. De La Torre S,Spruijt-Metz D, Farias AJ. Associations among wearable activity tracker use, exercise motivation, and physical activity in a cohort of cancer survivors: secondary data analysis of the Health Information National Trends Survey. JMIR Cancer; 2021;7(2):e24828.
9. Ohri N, Kabarriti R, Bodner WR, et al. Continuous activity monitoring during concurrent chemoradiotherapy. Int J Radiat Oncol Biol Phys. 2017;97(5):1061-1065. doi:10.1016/j.ijrobp.2016.12.030. Epub December 25, 2016.
10. Jercich K. Access to wearables could become a social determinant of health, researchers warn. Healthcare IT News. April 26, 2022. Accessed May 10, 2022. https://www.healthcareitnews.com/news/access-wearables-could-become-social-determinant-health-researchers-warnBack To Top
Beyond Measure: Remote Patient Monitoring With Wearables. Appl Rad Oncol.
Kerri Reeves is a freelance writer based in Ambler, PA.