in the United States alone, Seventy million adults You have a sleep disorder. In all, 35% of the US population gets less than seven hours of sleep, the recommended amount, each night.
Michael Kue, dean professor of biomedical engineering and pediatrics, and colleagues research at the University of Southern California Cooperative known as Bioengineering Sleep Health Center (or “SleepHuB”) You know this, and they are on the case. They acknowledge these sleep problems, as well as how technology can help. Professor Koo and his team are developing “smart systems” using wearable wristbands and mobile phones to get to the root of people’s sleep problems.
“These wearable bracelets are relatively cheap, and they can be made daily by people in their homes,” Khoo said. “They don’t need to go to the hospital or any kind of lab. That’s the main idea, if we have this thing that works well with a cell phone, we can give it to thousands of people, and they can wear it for days and days, and then we can collect a lot of data.”
In a project recently funded by Ming Hsieh InstituteKhoo’s team uses optical sensors in wearable wristbands to measure patients’ pulse waves, which reflect dynamic changes in blood volume in the subject’s small vessels. These vessels contract and dilate, causing fluctuations in the signals within the blood. In scientific terms, these are called “vascular oscillations”.
Incorporating the bracelets into this research makes studying these oscillations in patients in their home environment much easier and more effective in identifying problems a patient may be experiencing, compared to studying them in a laboratory.
“Sleep studies are intrusive and expensive, and they need many tools, so the idea is to try to commercially use the low-cost technology that is available on the market,” Kuo said, citing a big factor in why they chose to create the wristbands to conduct the studies.
The bracelets are commercially available, and with permission from the manufacturer, Khoo and his team have access to the raw data. Similar to other research being conducted at USC Viterbi using wearable technology, Custom programming and algorithms created for the project allow researchers to interpret information from the wristbands to help a patient with a specific medical problem.
Ku’s research was conducted in collaboration with Dr. CHLA’s Thomas Coates and Saranya Veluswamy focus specifically on people with sickle cell anemia, whose characteristic symptom is bouts of severe acute pain. Patients with sickle cell anemia, an inherent blood disorder, also have a higher prevalence of sleep-disordered breathing, such as sleep apnea. The USC-CHLA team hypothesizes that spontaneous vessel contractions during sleep are amplified by disrupted breathing during sleep, making sickle cell patients more likely to experience severe and potentially fatal pain crises.
“What we’re trying to track is when these vasoconstrictions occur, and that’s what we refer to in terms of these oscillations,” Kuo said.
The wearable bracelets allow the researchers to examine how the oscillations change, and how these changes can predict the onset of pain for a patient. Khoo says that their approach to determining the likelihood of these types of painful crises is not just measuring a patient’s pulse rate but also pulse size.
“These vasospasm oscillations can be triggered by stress, which makes your level of empathy go up,” Khoo said. Sympathetic levels, or nerves within the autonomic nervous system, directly affect things like heart rate, blood pressure, and breathing ability, which negatively affects sleep quality.
The collaboration between Khoo and various members of SleepHuB addresses other important problems related to sleep disorders. In a new multicenter project funded by the National Institutes of Health Khoo is collaborating with SleepHuB colleague Dr. Sally Ward of CHLA/USC, and other researchers on site to study children with sleep apnea and Down syndrome. One solution to sleep apnea, Khoo says, is to wear a mask that provides continuous positive pressure (“CPAP”). However, this particular solution is not well tolerated by individuals with Down syndrome.
“What we’re trying to do is see if we’re just giving oxygen, using a nasal tooth, to see if oxygen therapy will help. This hasn’t been proven before, which is why we’re trying to see if it might lead to Improve sleep apnea or not.
In another grant stemming from a collaboration developed through SleepHuB, Khoo is partnering with Dr. Eric Kezirian, professor of clinical otolaryngology and head and neck surgery at USC’s Keck School of Medicine and vice chair of the Caruso Department of Otolaryngology. Kezirian is one of the few surgeons in the country who specializes in the evaluation and surgical treatment of adults with snoring and sleep disorders, and the removal of tissue around the upper airways in patients with obstructive sleep apnea.
“This type of surgery is only 50 percent successful in the long run,” Kho said. “We’re trying to figure out how we can test patients to see if they’re likely to be successful with surgery.”
With deeper knowledge about the cause of patients’ sleep problems gained from applying computational algorithms developed by Dr. Khoo and other biological engineers, medical professionals like Dr. Kizirian can perform surgery more effectively. Other collaborations that have stemmed from SleepHuB include USC Suzanne Dworak-Peck Assistant Professor of Social Work, Karen Lincoln, Stress and Aging Expert.
“Dr. Lincoln’s team is trying to test for early-onset Alzheimer’s disease and dementia in elderly African Americans with a brain magnetic resonance imaging (MRI) application. They are incorporating wristbands to measure sleep quality in order to determine if lack of sleep accelerates the development of cognitive impairment,” Kho explained. .
Another SleepHuB collaborator, Professor Vitterbi Krishna Nayak, aims to use a low-field MRI scanner to study the dynamic patterns of the upper and lower airways of the lungs during sleep.
While sleep problems are caused by a variety of illnesses and disorders, it’s clear that Khoo and his collaborators at SleepHuB passionately deploy all technology resources to help their patients get a better night’s sleep.
Posted on January 19, 2023
Last updated on January 19, 2023