Supermarket trolleys could help prevent strokes on a mass scale — here's how
Shopping at a supermarket could save you from a stroke, but only if you shop using pulse-reading trolleys provided by a team of researchers at Liverpool John Moores University (LJMU).
The LJMU team modified regular supermarket trolleys by adding ECG (electrocardiogram) sensors to their handles. They then introduced the trollies to four Sainsbury's stores in Liverpool as a part of its 'SHOPS-AF' study.
The goal of this experiment was to see if the modified trolleys could screen shoppers for atrial fibrillation (AF)— the irregular beating of the heart that causes blood clots and increases the risk of a stroke by five times in a person.
In the last two months, about 2,155 adult shoppers who visited these stores agreed to use the modified trolleys instead of regular ones. Surprisingly, many of the participants were diagnosed with AF. All of them were referred to cardiologists, and this early diagnosis has probably saved them from the risk of stroke.
Most people don’t have the time for regular health and heat checkups, and they come to know about AF when they experience a stroke. With ECG-equipped trolleys, people can have their hearts regularly diagnosed without changing their daily routine.
Plus, if implemented on a large scale, this innovation may also significantly decrease the number of severe AF cases and stroke deaths.
How does a 'stroke-detecting' trolley work?
A person needs to hold the trolley handle for just 60 minutes, and within this time, the ECG sensors screen them for AF. A red light in the form of a cross flashes on the trolley handle in case the sensors detect irregular heartbeat.
However, if no AF signs are detected, a green tick sign becomes visible, suggesting the shopper has a normal heartbeat. During the study, the researchers screened over 2,000 shoppers using the trolleys and recorded red lights for 220.
The people diagnosed with AF were then checked by a cardiologist to confirm the AF signs. This manual test confirmed AF in only 59 individuals out of the 220. While 20 were already aware of their condition, 39 shoppers came to know for the first time that they had AF.
The disease currently affects over five million people in the U.S., and the Centers for Disease Control and Prevention (CDC) estimates that by 2030 the number of AF patients may rise to 12 million.
It’s one of the leading causes of stroke, but a diagnostic tool like the modified trolley can play a key role in preventing the disease at an early stage and on a mass scale. However, there's one catch.
The trolleys correctly detected signs of AF in 70 to 93 percent of patients. However, manual tests revealed that only 25 to 50 percent of the red-flagged patients actually had AF.
These findings suggest that although they offer an accessible way to diagnose AF, their screening results are not very accurate. Therefore, it is first crucial to increase the accuracy of the ECG sensors on trolleys before adopting this approach on a large scale.
Ian Jones, one of the researchers and a professor at LJMU said, “Nearly two-thirds of the shoppers we approached were happy to use a trolley, and the vast majority of those who declined were in a rush rather than wary of being monitored.”
He added, “This shows that the concept is acceptable to most people and worth testing in a larger study.” However, “before we conduct SHOPS-AF II, some adjustments are needed to make the system more accurate.”
The study was presented at the ACNAP (Association of Cardiovascular Nursing & Allied Professions) Congress 2023 on June 23.