Researchers at the Universitat Autònoma de Barcelona in Catalonia, Spain, have developed a system to monitor the severity of myalgic encephalomyelitis (ME), also known as chronic fatigue syndrome. The system includes a commercial chest strap sensor that measures heart rate variability and a paired app that collects, collates, and presents these data, allowing patients to monitor their condition and share information with their clinician.
ME is a debilitating condition, characterized by severe fatigue that interferes with daily activities. The prevalence of ME is expected to drastically increase in the coming years as it appears to be a common component of persistent COVID-19, also known as ‘long COVID’. ME may be triggered by persistent COVID-19, along with infection with other viruses, and some expect it to be a significant part of the wave of long COVID cases currently developing around the world. The condition does not currently have diagnostic biomarkers or eﬀective treatments, and historically has been largely overlooked and dismissed by medical science, so techniques to measure disease severity and track patient progress are surely welcome.
These researchers had previously discovered that heart rate variability, which encompasses small diﬀerences between consecutive heart beats and provides an indicator of autonomic nervous function, may be correlated with ME disease severity. “Specifically, we had observed that this variability was lower in patients with ME, especially in the most disabling cases,” said Dr. Jesús Castro, a researcher involved in developing the new system. “In this work we wanted to verify the relationship between heart rate variability and the syndrome in both women and men with ME compared to healthy controls and its usefulness for monitoring patients.”
In this latest study, the researchers used technology to measure heart rate variability, consisting of a chest strap sensor, and a paired app that could communicate with the sensor through Bluetooth. They measured hemodynamic properties in a group of male and female volunteers with ME, as well as in healthy controls. The results suggest that the technology could be particularly useful in women with ME, which is convenient, as the condition appears to predominantly aﬀect women.
“We demonstrated that the use of the app would be especially useful for the monitoring of women suﬀering from this syndrome, which clearly have a lower variability of heart rate compared to healthy women”, said Dr. Rosa M Escorihuela, another researcher involved in the study.
In the future, it should be possible to incorporate the same underlying technology into wearable devices, such as a smart watches, to improve patient convenience and make it easier for clinicians to obtain patient data.