AcuPebble wearable to diagnose sleep apnoea remotely

Traditionally, the diagnosis of OSA has required multiple hospital visits for patients, and doctors have had to manually review and analyse data from a patient’s sleep study. AcuPebble SA100 automates this process, instantly providing a clinically validated diagnosis equivalent to the current ambulatory gold standard.

This is particularly important in light of COVID-19 and the NHS move to digital first and remote consultations. AcuPebble SA100 gained CE Mark approval in September 2020 and is the product of more than ten years of research led by Professor Esther Rodriguez-Villegas at Imperial College London.

Obstructive sleep apnoea is a serious respiratory condition that affects approximately 175 million people in Europe and almost one billion people worldwide (up to 24% of the adult population and up to five percent of children are affected) . OSA causes sufferers to repeatedly stop breathing while they are asleep, and can lead to serious health implications including high blood pressure, type 2 diabetes and dementia. It is also the second most common cause of road accidents due to tiredness.

However, until now, the diagnosis of OSA has relied on complex, expensive and resource-intensive tests which require patients to wear an uncomfortable set of devices. Furthermore, the patient must come to hospital to learn how to use the device, then come back the day after using it, or alternatively spend the night at a sleep clinic. All of this combines to create major bottlenecks in hospitals, long waiting lists, and an increased risk of infection both for hospital staff and patients.

Professor Rodriguez-Villegas, inventor of the technology and founder of Acurable, commented: “Currently, only around 20% of people affected with sleep apnoea are diagnosed, and there are long waiting lists due to the scarcity of sleep clinics and the high costs of offering current sleep diagnostic tests. Furthermore, during the current coronavirus pandemic, this challenge has been further exacerbated. There is a backlog of patients who weren’t seen during the height of the crisis and a reluctance from patients to travel to hospital.

“What’s more, doctors are looking for ways to treat patients remotely to reduce the risk of infection. Acurable’s effective at-home testing enables earlier, more accurate and more cost-effective diagnosis of sleep apnoea, which will improve patient care, reduce co-morbidities and the risk of contagion, and which could save millions in hospital resources.”

With AcuPebble SA100, patients undertake their sleep test remotely. The device is small enough to be sent to patients in the post, and continuously and accurately monitors the patient’s breathing and cardiac biosignals in a non-invasive way while they sleep, and then automatically interprets the results.

The next day, doctors can instantly see the diagnosis without having to manually review the data themselves, while patients do not need to attend outpatient appointments or stay overnight at a sleep clinic, freeing up valuable time and resources for hospitals and medical staff, and providing a better experience for patients. AcuPebble is easy to use, and clinically proven to have the diagnostic equivalence of multi-channel polygraphy - the current gold standard for ambulatory sleep apnoea diagnosis - with 94% PPV and 98% NPV in a recent trial at NHS Royal Free Hospital London.

Dr Swapna Mandal, a respiratory consultant at the Royal Free London NHS Foundation Trust, commented: “It's thought that 1.5 million individuals in the UK have Obstructive Sleep Apnoea, and at the moment, 80 percent of those remain undiagnosed. That equates to one in 25 men and one in 50 women. A few years ago, we were maybe getting 500 or 600 referrals a year, we're now getting about 2,000.

“This was already a lot to deal with, especially given the long and often complex diagnostic pathway for sleep apnoea, but with the ongoing coronavirus pandemic, we now have an even bigger backlog of patients to see. What’s more, we’re moving to a digital first approach, so we’re trying to reduce the number of appointments taking place in the hospital.

“Last year, we ran a clinical trial with Acurable which demonstrated that the AcuPebble SA100 has diagnostic equivalence to the current ambulatory gold standard for obstructive sleep apnoea diagnosis. This is great news, especially now, as it means we can diagnose more patients, reduce the number of times these patients need to visit a hospital, and ultimately improve quality of life for those patients.”

Timothy St Jean, a 48 year old patient at the NHS Royal Free Hospital, said: “I noticed that I was getting tired during the day, and my children said to me that they could hear my snoring from my bedroom when their door was closed and when my door was closed. I was referred to a lung specialist who gave me this equipment to wear overnight.

“There was a belt that went across my stomach, and another one that went across my chest; there was also a device you put on your finger, and plastic tubing that went into your nose. It was quite a bit of equipment, and it wasn’t very comfortable to wear.

“In contrast, the AcuPebble was very easy, it’s got an adhesive on the back and you just stick it below your Adam’s apple. There’s an app you use on your phone which gives you a step by step guide to setting it up. It was very easy to use and very intuitive. Nothing gets in the way when you’re sleeping and you can turn over without disturbing the sensor. The AcuPebble was a lot easier to use than all the other paraphernalia.”

AcuPebble operates on the principle of acoustic sensing, whereby the body respiratory and cardiac functions generate sounds that can be recorded with a non-invasive wearable sensor. The acoustic signals are then transferred wirelessly to a mobile device and to the cloud, where patented algorithms automatically extract the physiological parameters used by doctors for the diagnosis and management of important conditions such as sleep apnoea, COPD, epilepsy and asthma.

In 2014, AcuPebble won the prestigious XPRIZE and Acurable has since been operating in stealth mode, focusing on perfecting the technology, building the team and obtaining all the regulatory approvals required to launch as a medical device. During this time, Acurable secured £2.1 in seed funding from Kindred Capital and Alma Mundi Ventures, as well as two Innovate UK grants worth £1.4m.

Acurable has also conducted a large clinical trial at the NHS Royal Free Hospital in London which demonstrated the safety and effectiveness of AcuPebble SA100 against multi-channel polygraphy. Most recently, Rodriguez-Villegas was awarded the Silver Award by the Royal Academy of Engineering for her work creating the AcuPebble technology.

In addition to improving diagnosis of sleep apnoea, Acurable is also working on product solutions to help improve the diagnosis and management of several other serious conditions such as COPD, pneumonia, epilepsy and asthma.