COPD is an incurable medical condition that causes breathing problems because of lung damage and affects over 1.2 million people in the UK. Although common, many people do not know they have it and in the UK, almost half of people affected have not been diagnosed. COPD costs the NHS £1.9 billion a year with the majority of cost linked with hospitalisations in the later stages of disease.
Along with a team of researchers, including academics from Portsmouth Hospitals University NHS Trust and the Nuffield Department of Primary Care Health Sciences at the University of Oxford, TidalSense examined data from four clinical studies between 2015 and 2022. These studies involved the collection of over 88,000 breath records in 295 patients who used the new N-Tidal fast response capnometer and had a variety of medical conditions which can affect breathing.
This capnometer contains a ground-breaking sensor that measures carbon dioxide in the breath more sensitively than previously possible and transmits the ‘waveform’ to a secure cloud platform using mobile data. TidalSense designed the device to use normal, relaxed breathing for a single minute, in a way that was comfortable for patients.
This high-resolution carbon dioxide data was then used to build and validate a diagnostic algorithm using machine learning. When the carbon dioxide data from a new patient is shared, the algorithm can tell whether that patient has COPD with a high degree of accuracy.
An updated version of the algorithm has subsequently been integrated with the device, so that it takes under five minutes from a patient breathing into the device to a diagnosis being available to a healthcare professional. In the future, it could be used to diagnose patients with COPD during their first appointment and because it is simple to use, can be administered by any healthcare professional.
Chris Carlin, consultant respiratory physician at NHS Greater Glasgow and Clyde, said: “The outcomes from this study are very promising. This AI-driven health technology looks to have the ability to diagnose patients with COPD far quicker and more reliably than with standard spirometry testing. Reducing exacerbations and hospitalisations are patients with COPD and healthcare providers’ top priorities. If N-Tidal’s diagnostic test could be introduced across the NHS, there’s a very real prospect of diagnosing patients with COPD sooner and starting optimised treatment earlier. This will reduce exacerbations, prevent deterioration in health and assist with the ambition to reorientate to preventative, rather than reactive care.”
The researchers have avoided using ‘black box’ artificial intelligence, allowing them to clearly see why the algorithm is determining that some patients have COPD and others do not. The algorithm has highlighted that certain parts of the carbon dioxide waveform are more important than others in making this determination, giving the team ground-breaking insight into the link between lung disease and carbon dioxide. This is a novel scientific discovery, only possible because of TidalSense’s first-of-its-kind combination of the sensor and artificial intelligence technology.
Current testing for COPD is done using spirometry, a technology which takes between 20 and 40 minutes per test and which has several known shortfalls. Furthermore, testing stopped during the pandemic, impacting already stretched patient wait times further; it’s estimated that in England alone, between 20 and 30,000 patients are awaiting a diagnostic test, with waiting times stretching from many months to years.
The team now plans to start piloting the device in clinical settings such as GP practices – bringing the benefits of the rapid, accurate AI-driven diagnostic test to NHS patients. They also anticipate further insights into the links between the carbon dioxide waveforms produced by N-Tidal and a range of other respiratory diseases in subsequent clinical studies.
Dr Ameera Patel, CEO of TidalSense said: “We know that COPD is now the third leading cause of death in the world. The current lack of accessible, accurate, and rapid diagnostic testing for COPD is contributing to a worsening of the current state of respiratory health. Waiting lists for a diagnostic test are quoted as being in excess of many months to years in some areas. Quick, reliable and accurate diagnostics have the potential to slash waiting lists and slow the trajectory of respiratory diseases.
“Our research shows that the N-Tidal device, coupled with our AI technology, can accurately diagnose patients with COPD within minutes (compared to spirometry which takes 30 minutes an appointment), at the point of care, meaning that patients can access treatments quicker. This will inevitably result in better patient outcomes and reduced healthcare costs.”