New mobile app could be useful to assess the severity of symptoms of chronic fatigue syndrome

Chronic Fatigue Syndrome / Myalgic Encephalomyelitis (CFS / ME) is a crippling disease in which people have great difficulty in carrying out daily activities. Despite its high prevalence, there are still no effective tools for its diagnosis, monitoring and treatment. To better understand and promote monitoring, as well as stratify fatigue in these patients, Vall d’Hebron, the Universitat Autònoma de Barcelona (UAB) and the Universitat Politècnica de Catalunya · BarcelonaTech (UPC) have developed a mobile application that could be useful in assessing the severity of fatigue in this syndrome, particularly in women. The results of the study in which this technology was tested were published in the journal Sensors.

The technology developed by UAB and UPC researchers consists of a chest belt with a sensor capable of measuring certain cardiac hemodynamic variables, connected via Bluetooth to a mobile application. The mobile app allows you to record and monitor heart rate variability and share the analyzed results with the medical staff who supervise the patients.

Specifically, this study analyzed the relationship between heart rate variability and symptom severity in women and men with CFS / ME. This parameter is closely related to heart rate, that is, the number of beats per minute of the heart. However, the time between two consecutive beats is not always exactly the same, but small differences that are normal can be detected: this is called heart rate variability (HRV). ).

In earlier studies published in the Journal of Translational Medicine, HRV has previously been linked to the assessment of the severity of fatigue in women with CFS / ME. “Concretely, we observed that this variability was lower in patients with CFS / ME, especially in the most disabling cases,” explains Dr. Jesús Castro, coordinator of the Chronic Fatigue Syndrome / Myalgic Encephalomyelitis laboratory in the Rheumatology group. Vall Hebron Research Institute (VHIR). A priori, it is considered positive to have a high variability, because it is an indicator of the good functioning of the autonomic nervous system. “In this work, we wanted to verify the relationship between HRV and the syndrome in women and men with CFS / ME compared to healthy controls and its utility for patient follow-up,” adds Dr. Castro.

Consistent with previous studies, it was found that measuring HRV with mobile application technology could predict the severity of disabling fatigue in patients with chronic fatigue syndrome / myalgic encephalomyelitis. This was particularly observed in the case of women, but this relationship was not as clear in the case of men. “We have shown that use of the app would be particularly useful for monitoring women with this syndrome, who clearly have lower heart rate variability compared to healthy women,” says Dr Rosa M Escorihuela, from the psychiatry service. and UAB forensic medicine. Thus, HRV would be a good predictor of the severity of fatigue during the clinical course of the disease.

The study was carried out on 77 patients with this CFS / ME (32 men and 45 women) and their results were compared with those of a control group. The HRV assessment was performed in 3 sessions of 5 minutes, spaced one to three weeks apart and under controlled conditions.

This study was carried out in part thanks to the R&D project PID2019-107473RB-C21, coordinated by researchers from UAB and UPC, and funded by the French Ministry of Science and Innovation.

Improved, non-invasive technology

Dr Juan Ramos Castro, from the Electronic and Biomedical Instrumentation Group and the Department of Electronic Engineering at UPC, comments that “the experience of the research groups at UAB and UPC has made it possible to correct the limitations of more important presented by this technology such as as errors in the measurement of heart variability produced by incorrect positioning of the chest belt and / or the movement and breathing of the patient during recording, and obtaining the recordings in controlled conditions to reduce the influence of other external factors. The results of the analysis are stored on a single and secure server and can be viewed via a specific platform. “Dr Lluís Capdevila, researcher at the Department of Basic, Evolutionary and Educational Psychology and at the Sports Research Institute of the UAB adds that “this is a non-invasive technology that is easy to use by patients or users, through your mobile device. This way they can perform self-assessments in ecological situations and could be tracked. in real time”.

As Dr Lluís Capdevila comments, “the same system has emerged and has been used successfully for real-time monitoring and tracking of the relationship between physical exertion and recovery, both in athletes and in the general population. For example, sports clubs such as Futbol Club Barcelona (women’s basketball and football sections) or New York City FC have used this system, and national teams such as the Spanish Basketball Federation, the Spanish Field Hockey Federation (male and female) or the Spanish Federation of Mountain Sports and Climbing “.

Vall d’Hebron, member of the European network on myalgic encephalomyelitis / chronic fatigue syndrome

In Catalonia, it is estimated that there are currently between 350,000 and 500,000 people affected by chronic fatigue syndrome / myalgic encephalomyelitis, and 2 out of 3 affected are women. Globally, a prevalence of between 17 and 25 million people with this affectation is estimated. In addition, these numbers are expected to double by 2030 due to the persistence of COVID-19, a disease in which patients have similar symptoms: this is called chronic postviral fatigue syndrome, which has already been described in other coronaviruses (SARS-CoV-1 and MERS) for other viruses such as Ebola, Epstein-Barr and cytomegalovirus.

Severe fatigue is the main symptom of CFS / ME, in addition to problems with immediate memory and speed of information processing and concentration, intolerance to physical / mental exercise, pain and dizziness. This syndrome can be very debilitating, but despite this, there are currently no diagnostic biomarkers or specific treatment options, so it is important that experts in the field work in a coordinated manner to improve care and support. burden of these patients.

In this sense, Drs. José Alegre and Jesús Castro, both from Vall d’Hebron, are members for Spain of the European Network on Chronic Fatigue Syndrome / Myalgic Encephalomyelitis (EUROMENE), which includes 55 professionals from 22 European countries. A consensus document on therapeutic and diagnostic approaches for this syndrome was recently published in the journal Medicina.

This document brings together the diagnostic criteria used in the participating countries as well as the experience of professionals in the care and treatment of patients, taking into account both pharmacological and non-pharmacological therapies. In addition, experts present recommendations, European and international, for the management of these patients. “It is necessary to have a health system that takes into account patients with chronic fatigue syndrome / myalgic encephalomyelitis, a pathology that has a great socio-economic impact”, explains Dr José Alegre, of the Unit of experience in central consciousness syndromes of rheumatology. Department of Vall d’Hebron University Hospital. Experts estimate that there should be between 2 and 4 specialist physicians for every million inhabitants with the support of a multidisciplinary team, such as nurses, physiotherapists, rehabilitators, occupational therapists, psychologists, nutritionists, social workers, etc.

It should be noted that not all countries have the same services for the management of patients with CFS / ME. In this sense, Catalonia is a leader in terms of the care of these patients, because in our territory, several units are formed in this field to diagnose and treat this syndrome. More specifically, Vall d’Hebron has an experience unit in central sensitization syndromes, within the rheumatology department, which works on both chronic fatigue syndrome / myalgic encephalomyelitis and fibromyalgia.