What recent advancements mean for the perception of home sleep testing for diagnosis, titration, and chronic disease management.
By Chaunie Brusie, RN, BSN
In March, the US Food and Drug Administration (FDA) cleared the next generation of Wesper’s patch-based home sleep testing system for assisting in the identification of sleep apnea in adult patients. Unlike the company’s first-generation device, the new design has longitudinal sleep monitoring at the forefront. The flexible abdominal and thoracic patches have a replaceable adhesive layer, and their electronics are rechargeable—in order words, a single wearable Wesper device can facilitate the diagnosis, titration, and long-term management of a patient’s sleep therapy, all while the patient remains comfortable sleeping in their home environment.
Wesper has identified disposable home sleep testing and longitudinal sleep testing as two trends in sleep medicine, says the company’s chief medical officer Jeffrey Durmer, MD, PhD. While the former allows for an easy operation to conduct a single diagnostic study, it also comes with environmental costs and only provides a glimpse into the patient’s sleep. Longitudinal testing, on the other hand, enables a more comprehensive view of the patient’s sleep patterns over time that can help optimize and personalize the therapy.
“Only a validated and FDA-cleared sleep testing device can demonstrate sleep physiology to this extent, which allows medical and dental professionals to make therapy management decisions in real-time,” Durmer says.
Clinical-grade longitudinal data collection has the potential to improve the accuracy and reliability of home sleep testing, he says—and may also usher in a new era in physician perceptions of home sleep testing’s usefulness as a tool for diagnosing and managing sleep disorders. In fact, changes in the perception of the utility of such testing beyond screening and diagnosis are already afoot.
“We are not getting actual requests for ‘longitudinal home sleep testing’ per se, but we have moved the majority of our home sleep apnea testing to a multi-use disposable option with the NightOwl,” says Kyle Miko, CRT/CSE, founder and chief marketing officer of VirtuOx. “This device allows up to 100 hours of usage over a few years, so prescribers can easily order additional testing when clinical correlation is needed. Because the device is already in the house, it’s a simple process. We only need to send a new activation code to the device so the patient can resume testing if their physician prescribed the test.”
Limitations of CPAP Data
While at-home therapy efficacy monitoring may be the standard of care for many other conditions, the world of sleep monitoring data is limited to a snapshot of a single night or, in some cases, over a few nights, explains Nox Medical product specialist Byron Jamerson, RPSGT, RST, CCSH, FAAST.
Since sleep and other physiologic parameters change, that means sleep professionals are working with limited information—which is exactly where longitudinal data can change the game. “Positive airway pressure devices provide some nightly data with downloads. But these do not provide any respiratory waveform data for the most part, and we are counting on ‘black box’ data that cannot be reviewed in detail,” he says.
“Data from CPAP devices can be helpful but is lacking data on effort (central versus obstructive),” says James Blevins, a product manager at Cadwell, which built the newest version of ApneaTrak to record for one, two, or three nights based on user feedback. “If the issue was allowing patients to see their own trends, then the data from the CPAP machine might very well be sufficient. But if the clinical user wants to assess efficacy, then I think they frequently want to look deeper than the CPAP flow and open/closed airway algorithms in most CPAP machines.”
CPAP devices also do not typically provide any data on SPO2, heart rate, or sleep time, though estimates can sometimes be obtained through non-FDA-cleared sleep wearables, Miko says. “These additional parameters can be helpful to ascertain if the patient’s machine is meeting their needs,” he says. “For example, if they are compliant on their APAP but have large amounts of time below 90% SPO2, they may need to be evaluated by their sleep physician.”
Nonetheless, if patients are not adherent to their CPAP therapy, sleep professionals typically have no longitudinal sleep data whatsoever.
Benefits of Longitudinal Data
Sonia Ancoli-Israel, PhD, a professor emeritus of psychiatry at the University of California San Diego and a Wesper consultant, says the ability to collect longitudinal data is important for obstructive sleep apnea (OSA) because the condition can vary widely from night to night. Easily recording many nights of sleep can lead “to more personalized treatment and a greater probability of long-term treatment success,” she says.
She also sees a benefit of longitudinal data collection in allowing for continual reevaluation of treatment efficacy and assessment of patient changes, such as weight gain or loss, that could necessitate adjustments.
Carlos Teixeira, RPSGT, EST, BSc, clinical affairs manager at Nox Medical, shares that perspective. “Taking patients to the sleep lab, one night, and setting or defining the therapeutical/treatment based on that sole night—especially if that’s the first time the patient is in contact with the therapy—is not the best we can do for our patients,” he says.
Teixeira, who is also president of the European Society of Sleep Technologists, adds that data collection and titration over multiple nights could help turn around patient nonadherence. Not only can it help overcome that “first night effect”—when patients tend to sleep worse on the first night of testing—but it can also help familiarize a patient with the therapy and device and encourage an increased comfort level in using the device over time.
“This will help patients’ comfort with more personalized treatment but also move towards a more adherent patient,” he says.
Phillip Dukes, vice president of clinical research for Sunrise, says longitudinal data collection can be helpful for those patients who remain symptomatic despite adequate adherence. “These patients are difficult to predict and often require additional longer-term monitoring while on therapy,” he says.
The reusable nature of the wearable Wesper device allows for night-to-night sleep physiology measurements that demonstrate the impact of CPAP and/or oral appliance therapy each night. Clinicians can use that data to adjust the airway pressure or other device settings. Over time, the longitudinal data can also enable clinicians to identify changes and trends in a patient’s sleep patterns not apparent through single-night testing. “This capability has the potential to provide a more affordable and optimal therapy in shorter timeframes,” says Wesper CEO Amir Reuveny, PhD.
Bogi Palsson, CEO of SleepImage, a marketer of software as a service that aids in the evaluation of sleep disorders, says, “When the physician will see objective improvement of the treatment based on the test results, coupled with the patient’s subjective feeling of improvements in quality of life and potentially reduced need for medications, the perception towards home sleep testing will become as obvious as it is currently in the treatment of hypertension or diabetes.”
Chronic Disease Management
Speaking of diabetes and hypertension, clinical-grade longitudinal data collection also helps move sleep disorders like OSA into the category of chronic diseases. “OSA is a chronic disease, and management should be approached the same way management of other chronic diseases is approached,” Ancoli-Israel says.
Hani Kayyali, CEO and president of CleveMed, says, “For many years now, we have been touting the fact that sleep apnea therapy needs to be monitored over time, just like any other chronic condition. Therapy efficacy is standard of care in other conditions.”
What’s more, Durmer points out that many other sleep disorders also require treatments that are used every day—like medications for restless legs syndrome or narcolepsy—or require behavioral changes that may take adjusting over time, such as relaxation techniques or cognitive behavioral therapies.
It’s those day-to-day therapies, Durmer says, that necessitate managing sleep disorders and sleep therapies similar to the management that patients with other chronic conditions experience, like medication therapies for diabetes, seizures, or migraines. And just like new physiological monitoring technology is emerging for conditions like diabetes with continuous blood glucose monitoring, so is that for sleep disorders.
“Having actual physiological sleep data on a day-to-day or month-to-month basis provides objective therapeutic evidence of the impact of a treatment or treatments, providing clinicians with an entirely new objective information stream that can be used to adjust therapies in real-time,” Durmer explains.
And Palsson says that, historically, sleep disorders have been mostly objectively evaluated at one point in time, while insomnia usually has not even been objectively measured. Longitudinal data could help a broader range of sleep disorders get the recognition and management they deserve as chronic conditions.
For now, limitations of third-party payor reimbursement for longitudinal monitoring will continue to be a barrier to adoption.
A shifting landscape from a procedure-based medical system to a value-based one may help, Dukes says. Sunrise leadership believes that long-term monitoring of patients will provide significantly important data points that will allow for earlier interventions for patients who may need a different therapy, adjunct therapy, or further intervention. He adds, “By focusing the sleep physician on the more complex patients, you get some cost savings and improved timeliness of patient care.”
Kayyali notes that while the reimbursement environment for remote patient monitoring (RPM) for sleep is still unclear, there are “favorable signs” that point to its adoption by payors. “If RPM reimbursement becomes mainstream—and as long as RPM technologies are easy to use in the home—then a new phase of sleep care will take hold, which is great,” he says.
At Wesper, the longitudinal monitoring is set up so physicians pay a monthly access fee per patient to use the device’s software platform and sleep testing. “The longitudinal information can be used to guide therapy and monitor patients over time with existing reimbursement codes,” Durmer says.
Nox’s Jamerson posits the advance of clinical-grade longitudinal data technology will actually help pave the way for more payors to see its importance and recognize the need for reimbursement. And while there are admittedly still challenges, such as staffing, reimbursement, and patient acceptance, it may be a step forward.
“This is a small price to pay for significantly better patient care,” Jamerson says.