New App for Assessing Myalgic Encephalomyelitis/Chronic Fatigue Symptoms

Understanding Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Myalgic encephalomyelitis, commonly referred to as chronic fatigue syndrome (ME/CFS), is a persistent illness characterized by debilitating fatigue that is not alleviated by rest. Additional symptoms often include unrefreshing sleep, difficulties with concentration and attention, slow information processing, and intermittent pain. Current estimates suggest that chronic fatigue affects between 836,000 and 2.5 million Americans, although these figures may be underreported due to the challenges associated with diagnosing the condition. The diagnostic difficulties can exacerbate patients’ symptoms and overall distress. Young adults aged 20 to 40 are most frequently impacted, with women being twice as likely to be affected. Furthermore, the number of cases is projected to double by 2030 as a potential consequence of long-haul COVID-19, with ongoing research needed to explore the connection between these two conditions.

Current Diagnostic Methods for Chronic Fatigue

Typically, doctors diagnose chronic fatigue using brain imaging techniques, such as magnetic resonance imaging (MRI), magnetoencephalogram (MEG), positron emission tomography (PET), or microRNA expression. However, these procedures can be costly. Consequently, researchers have been investigating alternative, more affordable, and non-invasive diagnostic methods. One promising approach utilizes heart rate variability (HRV), which measures the fluctuations in time intervals between heartbeats. Healthy HRV is complex and enables the body to adapt to swiftly changing circumstances.

Heart Rate Variability and Chronic Fatigue

Studies indicate that individuals with chronic fatigue exhibit distinct differences in heart rate variability when compared to healthy individuals. This information has been utilized by healthcare professionals to evaluate the severity of chronic fatigue symptoms. Moreover, HRV testing is relatively simple and can be effectively integrated into an application designed for chronic fatigue assessment.

Researching App-Based Detection of Chronic Fatigue

Due to the higher prevalence of chronic fatigue in women, there has been a lack of studies focused on men, particularly regarding differences in heart rate variability between genders. Researchers from Vall d’Hebron, Universitat Autònoma de Barcelona (UAB), and Universitat Politècnica de Catalunya BarcelonaTech (UPC) conducted a study to evaluate the effectiveness of an app in analyzing heart rate variability in men with chronic fatigue and to identify any differences in symptoms experienced by men and women. The findings were published in the journal Sensors.

The study involved 77 patients with chronic fatigue (32 men and 45 women) and 44 healthy controls. Participants completed five questionnaires assessing physical symptoms, fatigue impact, autonomic function severity, sleep quality, and levels of anxiety and depression. Following this, participants wore a cardiac chest band that recorded heart rate data, which was transmitted via Bluetooth to the chronic fatigue app for analysis. Measurements were taken across three five-minute sessions spaced one to three weeks apart.

Findings on Heart Rate Variability and Chronic Fatigue Severity

After analyzing the data statistically, researchers found that HRV data collected through the app could predict the severity of chronic fatigue symptoms. The correlation was particularly strong in women, while the results for men were less definitive, although they indicated greater cardiac variability. Although the questionnaire responses and HRV data did not consistently reveal a direct relationship suitable for diagnosing chronic fatigue, researchers observed that high fatigue or gastrointestinal dysfunction was linked to lower HRV in men.

Dr. Rosa M. Escorihuela, one of the study’s authors, noted in a press release, “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.”

References

1. What Is ME/CFS? – American ME and CFS Society. American Myalgic Encephalomyelitis and Chronic Fatigue Syndrome Society. Accessed July 5, 2021. https://ammes.org/what-is-mecfs/
2. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) | CDC. www.cdc.gov. Published December 30, 2020. Accessed July 5, 2021. https://www.cdc.gov/me-cfs/
3. Capdevila L, Castro-Marrero J, Alegre J, Ramos-Castro J, Escorihuela RM. Analysis of Gender Differences in HRV of Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Using Mobile-Health Technology. Sensors. 2021;21(11):3746. doi:10.3390/s21113746
4. Shaffer F, Ginsberg JP. An Overview of Heart Rate Variability Metrics and Norms. Frontiers in Public Health. 2017;5. doi:10.3389/fpubh.2017.00258
5. Myalgic encephalomyelitis/chronic fatigue syndrome | Genetic and Rare Diseases Information Center (GARD) – an NCATS Program. rarediseases.info.nih.gov. Accessed July 5, 2021. https://rarediseases.info.nih.gov/diseases/7121/myalgic-encephalomyelitis-chronic-fatigue-syndrome
6. An app to help assess the severity of symptoms in chronic fatigue syndrome. EurekAlert! Published July 1, 2021. Accessed July 5, 2021. https://www.eurekalert.org/pub_releases/2021-07/uadb-aat070121.php
7. Wong TL, Weitzer DJ. Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)—A Systemic Review and Comparison of Clinical Presentation and Symptomatology. Medicina. 2021;57(5):418. doi:10.3390/medicina57050418