The smart shirt has proved to be accurate when compared to traditional testing equipment, according to research presented at the European Respiratory Society International Congress.
Researchers have used the smart shirts and a mobile app to measure breathing in healthy people as they go about everyday activities. They now plan to test the garment with patients with COPD (chronic obstructive pulmonary disease) with doctors monitoring for early signs that their condition is getting worse.
The research was presented by Denise Mannée, a technical physician and PhD candidate at Radboud University Medical Centre in The Netherlands.
"COPD is a growing problem with around 64 million people suffering with the condition worldwide,” said Mannée. “When patients suffer an increase in their symptoms, such as coughing and breathlessness, they need to be monitored more closely. Symptoms first occur during daily activities like climbing stairs and housework, but respiration is hard to monitor in such conditions. This is traditionally done in the clinic with equipment such as an exercise bike, facemask and computer. The equipment is not very practical for measuring everyday activity.
"Smart shirts are already available, but they tend to be used by professional or amateur sportsmen and women. We wanted to see whether a smart shirt could provide an accurate and more practical alternative for measuring lung function."
Dubbed Hexoskin, the smart shirt senses how the fabric stretches when the wearer's chest expands and contracts and uses these measurements to gauge the volume of air inhaled and exhaled. It also records heart rate and movement. Mannée and her colleagues asked a group of 15 healthy volunteers to wear a smart shirt while doing everyday activities including lying down, sitting, standing, climbing stairs and vacuuming. The volunteers simultaneously wore equipment traditionally used to measure breathing that includes a face mask and backpack. The volunteers repeated the tasks again wearing both pieces of equipment, to generate a second set of data.
Researchers then compared the measurements recorded using the two techniques for each person doing each activity on the two occasions. In general, they found that the measurements were very similar. When lying, the difference between measurements taken by the two pieces of equipment was just 0.2 per cent on average, which only represents a few millilitres of air. In more strenuous activities such as vacuuming the difference was 3.1 per cent on average, or around 40ml.
The researchers noted that calibrations from the first use of the Hexoskin did not prove reliable for the second set of measurements, suggesting the equipment would need to be recalibrated each time the Hexoskin was used.
"These results are important because they indicate that the smart shirt can be worn by patients while they go about their daily lives to accurately measure their lung function,” said Mannée.
Participants said the smart shirts were comfortable and could be worn underneath their normal clothes. The researchers now plan to repeat tests on the smart shirts with COPD patients, but they believe the technology might also help in other respiratory conditions such as asthma, cystic fibrosis or after transplantation.
"Ultimately, we want to improve patients' quality of life. If we can accurately monitor patients' symptoms while they go about their normal activities, we might be able to spot problems and treat them sooner, and this in turn could mean less time in hospital,” said Mannée.