The University of Arizona

UA Researchers Design Wearable Device to Detect Risk of Falling

By Alexis Blue, University Communications | December 5, 2012

An interdisciplinary team of researchers is working on a wearable pendant that can detect an elderly person's risk for falling and automatically alert medical personnel when a fall has occurred.

Bijan Najafi
Bijan Najafi
Jane Mohler
Jane Mohler

Many of us remember the classic television commercial – the one in which an elderly woman, after stumbling in her home, presses her medical alarm button to utter the famous phrase, “I’ve fallen, and I can’t get up.” But what if she could have known she was going to fall before it happened?

Researchers at the University of Arizona are working on technology that may make that possible.

A team led by co-principal investigators Bijan Najafi, a biomedical engineer and associate professor of surgery in the UA College of Medicine, and Jane Mohler, professor of medicine and co-director of the Arizona Center on Aging, is working to develop a wearable device that can predict risk of falls in elderly patients and send automatic alerts to loved ones or emergency personnel when a fall has taken place.

“We are addressing one of the very important challenges in our current society – that is aging and the problems associated with aging,” said Najafi, who also directs the UA’s Interdisciplinary Consortium on Advanced Motion Performance, or iCAMP.

In the United States, it is estimated that one in three people older than 65 fall every year, and between 20 and 30 percent of those falls result in moderate to severe injury, Najafi said. The cost of treating falls in elderly patients is approximately $28 billion annually, and as the country’s baby boomers age, the problem is expected to become even more prevalent and costly.

The UA team – working in partnership with BioSensics, a company that specializes in wearable medical devices – has developed a prototype of a wearable, wireless device, engineered to detect warning signs of fall through sensors that measure key fall risk indicators, such as a person's balance, gait stability and regularity, or the amount of time it takes an individual to rise from a chair.

The initial prototype, about the size of a cell phone and worn inside a shirt, is currently undergoing clinical testing through the Arizona Center on Aging, under Mohler's direction.

The researchers are studying 120 individuals older than 65 and with varying levels of frailty to see how well the device works at predicting fall risk, as well as whether it can help clinicians identify signs of frailty. 

Two years from now, Najafi hopes the device will be simplified to a small pendant a patient can wear around his or her neck that automatically will send the information it records to patients, health-care providers, family members and even the local emergency room.

“Our goal is that this device should be very easy to use, and everything would be sent in real time,” Najafi said. “If a fall occurs, that information would be sent to a care provider to see if there was an injury. If there was indication of decline in function or increased risk of falling, another alert would go out to indicate need for intervention.”

The idea is to detect risk early enough that medical professionals can intervene, improving patients’ strength, balance and flexibility before a fall occurs. 

“We know that after a fall it’s too late; we need to do something preventative,” Najafi said.

Interventions may vary, since a number of variables can contribute to increased risk of fall, Najafi said. For example, something as simple as a change in medication might negatively affect a person’s mobility. If the sensor detects problematic changes in gait or balance following the prescription of a new medication, it could alert a patient and his or her doctor to reconsider the drug.

Other factors that can contribute to fall include failing vision, the onset of a medical disorder or muscle weakness because of lack of exercise, Najafi said. (Najafi's team is working on a separate project to address elderly patients' exercise needs through a virtual reality-based video game designed to help them master skills like avoiding obstacles.)

If a patient does fall while wearing the device, the idea is that an automatic alert would be sent without the patient needing to push a button or speak to an operator.

“Currently everything is manual – a push-button system,” Najafi said. “That’s a good step forward, but the challenge is that sometimes people fall and they lose consciousness or they don’t know what action they need to do, so we would like to automatize this process. There are many efforts in that direction, but most of them fail because they record too many false alarms.”

The two-year project, funded by a $1.2 million National Institutes of Health grant, is an interdisciplinary collaboration among the UA department of surgery, the Arizona Center on Aging and industry partner BioSensics, which Najafi hopes will be able to market the final product to individuals. 

“After the next two years, we hope to market this device and make it accessible to the target population who may benefit from it, and this is what is important for us because we don’t like our research to be stuck in paper with nobody using it,” Najafi said. “Our society can benefit from this development.”

Dr. David Armstrong, professor of surgery and a key investigator on the project, says the final product could go a long way toward helping seniors live independently longer.

“These are folks that are used to being active and productive and they want to be at home; they don’t want to be in a nursing home,” he said.

Armstrong likens the wearable device to “a security system, not for your house but for your body.”