Evidence browser

Long COVID diagnostic with differentiation from chronic lyme disease using machine learning and cytokine hubs.

Patterson, Bruce K, Guevara-Coto, Jose, Mora, Javier et al.·Scientific reports·2024

Researchers developed a computer-based test using blood measurements called cytokines to accurately identify long COVID (also called PASC) in patients. The test was able to correctly identify long COVID in 97% of cases and correctly rule it out in 90% of cases when tested on a new group of people. Importantly, the test could also distinguish long COVID from chronic Lyme disease, which can cause similar symptoms, helping doctors diagnose the right condition.

In major dysmood disorder, physiosomatic, chronic fatigue and fibromyalgia symptoms are driven by immune activation and increased immune-associated neurotoxicity.

Maes, Michael, Almulla, Abbas F, Zhou, Bo et al.·Scientific reports·2024

This study found that people with severe depression often experience fatigue and pain symptoms similar to ME/CFS, and these symptoms are linked to overactive immune responses in the body. Researchers measured immune molecules in the blood of severely depressed patients and healthy controls, and discovered that specific immune markers—particularly IL-16 and IL-8—were associated with how severe the fatigue and physical symptoms were. The study suggests that difficult life experiences and traumatic childhood events may trigger these immune changes, leading to the physical symptoms that patients experience.

Service users' and parents/carers' experiences of a paediatric chronic fatigue service: A service evaluation.

Hartley, Gemma, Purrington, Jack·Chronic illness·2024

This study asked children with chronic fatigue syndrome (ME/CFS) and their parents about their experiences at a specialist clinic that treats young people with the condition. Most families felt the service helped them understand their illness better, learn useful strategies to manage their symptoms, and gradually increase their activity levels safely. However, some families had trouble accessing the service due to its location, appointment scheduling, and difficulty contacting staff.

Gut MicrobiomeImmune System

Systemic antibody responses against gut microbiota flagellins implicate shared and divergent immune reactivity in Crohn's disease and chronic fatigue syndrome.

Bourgonje, Arno R, Hörstke, Nicolai V, Fehringer, Michaela et al.·Microbiome·2024

This study looked at immune responses in ME/CFS and Crohn's disease patients by measuring antibodies against proteins from gut bacteria called flagellins. Researchers found that both patient groups had elevated antibodies against these bacterial proteins, but the pattern of where these antibodies attached differed between the two diseases. These antibody patterns could potentially help doctors diagnose ME/CFS and understand how the immune system may be responding abnormally to gut bacteria.

E2 ModerateCohortPEM requiredObservational

Mismatch between subjective and objective dysautonomia.

Novak, Peter, Systrom, David M, Marciano, Sadie P et al.·Scientific reports·2024

This study examined whether questionnaires that ask patients about autonomic symptoms (like dizziness, heart racing, or sweating problems) match what doctors find when they perform actual autonomic tests. Researchers studied over 2,600 patients and found a surprising disconnect: questionnaires and actual tests did not correlate with each other, meaning some patients reported severe symptoms but tested normally, while others had significant test abnormalities but reported few symptoms. This finding held true across many conditions, including ME/CFS, suggesting that questionnaires alone cannot reliably detect autonomic problems.

Autonomic Nervous System

Cardiopulmonary and metabolic responses during a 2-day CPET in myalgic encephalomyelitis/chronic fatigue syndrome: translating reduced oxygen consumption to impairment status to treatment considerations.

Keller, Betsy, Receno, Candace N, Franconi, Carl J et al.·Journal of translational medicine·2024

This study tested 84 people with ME/CFS and 71 healthy controls on an exercise bike on two days, 24 hours apart. People with ME/CFS performed worse on the second day of testing—their oxygen use, heart rate, and exercise capacity all declined—while healthy people stayed about the same. This objective decline mirrors the real-world experience of post-exertional malaise, where ME/CFS patients feel worse after physical activity.

E2 ModerateCohortPEM unclearLongitudinal

Association Between Chronic Pain and Fatigue Severity with Weather and Air Pollution Among Females with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).

Jones, Chloe Lisette, Haskin, Olivia, Younger, Jarred Wayne·International journal of environmental research and public health·2024

This study looked at whether weather and air quality affect pain and fatigue in women with ME/CFS. Fifty-eight women tracked their daily pain and fatigue levels for about 2 months while researchers compared their symptoms to local weather and air pollution data. The results showed that worse air quality, lower wind speeds, and higher levels of certain pollutants were linked to days when patients experienced more pain and fatigue.

E2 ModerateCohortPEM requiredCross-Sectional

Impaired Hand Grip Strength Correlates with Greater Disability and Symptom Severity in Post-COVID Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Paffrath, Anna, Kim, Laura, Kedor, Claudia et al.·Journal of clinical medicine·2024

Researchers tested hand grip strength in 144 women with long-COVID symptoms, comparing those who met strict ME/CFS criteria (78 patients) with those who had other long-COVID symptoms. People with ME/CFS showed weaker grip strength and more severe disability, fatigue, and symptom worsening after activity compared to other long-COVID patients. Weak grip strength appeared to be connected to the core symptoms that define ME/CFS, suggesting muscle weakness in ME/CFS may share a common cause with other hallmark symptoms.

Exploring the role of galectin-9 and artemin as biomarkers in long COVID with chronic fatigue syndrome: links to inflammation and cognitive function.

Elahi, Shokrollah, Rezaeifar, Maryam, Osman, Mohammed et al.·Frontiers in immunology·2024

Researchers studied two proteins in the blood—galectin-9 and artemin—to see if they could help identify people with Long COVID who also have ME/CFS. They found that galectin-9 levels were higher in Long COVID patients and were linked to inflammation and thinking problems. These proteins may help doctors distinguish Long COVID with ME/CFS from people who recovered normally from COVID-19.

E2 ModerateCohortPEM requiredCross-Sectional

Comparison of T-cell receptor diversity of people with myalgic encephalomyelitis versus controls.

Dibble, Joshua J, Ferneyhough, Ben, Roddis, Matthew et al.·BMC research notes·2024

Researchers studied immune cells called T-cells in people with ME/CFS to see if they were different from those in healthy people. They looked at genetic patterns in blood samples from 40 people in each group: those severely affected by ME/CFS, those mildly or moderately affected, people with multiple sclerosis, and healthy controls. Although they used advanced technology and computer programs to analyze the data, they found that the T-cell patterns were not notably different between the groups.

E2 ModerateCohortPEM unclearCase-Control

A case-control study of reaction time deficits in a 3D virtual reality in patients with Post-COVID syndrome.

Güttes, Moritz, Lucio, Marianna, Skornia, Adam et al.·Scientific reports·2024

Researchers tested whether people with Post-COVID syndrome have slower reaction times when responding to visual stimuli shown in virtual reality glasses. They found that Post-COVID patients were indeed slower and less accurate at this task compared to healthy controls, suggesting this test might be a useful tool for identifying Post-COVID cognitive problems in the future.

Cognitive Impairment

E2 ModerateBehavioralPEM not requiredCase-Control

Psychological flexibility in somatic symptom and related disorders: A case control study.

Selker, René J D M, Koppert, Tim Y, Houtveen, Jan H et al.·Journal of psychiatric research·2024

This study looked at how well people can handle difficult thoughts and feelings without being overwhelmed by them—a skill called psychological flexibility. Researchers compared 154 people with somatic symptom disorder (SSD, where people are very distressed by physical symptoms) to nearly 2,000 people with other conditions like ME/CFS or no illness. People with SSD had much lower psychological flexibility than both other groups, and this lower flexibility was linked to worse mental health.

Stroop task and practice effects demonstrate cognitive dysfunction in long COVID and myalgic encephalomyelitis / chronic fatigue syndrome.

Baraniuk, James N, Thapaliya, Kiran, Inderyas, Maira et al.·Scientific reports·2024

This study tested how quickly people with Long COVID and ME/CFS could complete a simple task involving reading color words displayed in different colored inks. Both patient groups were noticeably slower at this task than healthy people, and unlike healthy people, they didn't get faster with practice. This suggests that ME/CFS and Long COVID may involve a problem with how different parts of the brain communicate during problem-solving.

Cognitive Impairment

Cognitive reserve as a protective factor against cognitive impairment in chronic fatigue syndrome.

Surendran, Gopika, Jose, Tony P·Applied neuropsychology. Adult·2024

This study examined whether people's life experiences and education—called 'cognitive reserve'—help protect them from the thinking and memory problems common in ME/CFS. Researchers tested 91 people with ME/CFS and found that those with more cognitive reserve had fewer cognitive problems. The severity of someone's ME/CFS was the main factor affecting both cognitive reserve and cognitive problems, rather than age or gender.

Cognitive Impairment

Overlapping conditions in Long COVID at a multisite academic center.

Grach, Stephanie L, Dudenkov, Daniel V, Pollack, Beth et al.·Frontiers in neurology·2024

This study looked at 247 patients with Long COVID who visited Mayo Clinic to see what new health problems developed after their COVID-19 infection. Researchers compared them to 40 people who had COVID-19 but recovered normally. The results showed that Long COVID patients experienced much higher rates of pain, neurological symptoms, sleep problems, and other issues. Importantly, 58% of Long COVID patients screened positive for ME/CFS—a serious fatigue and post-exertional symptom condition—compared to none of the control group.

Sleep

E2 ModerateCohortPEM unclearObservational

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: Impact on Quality of Life (QoL) of Persons with ME/CFS.

Muirhead, Nina L, Vyas, Jui, Ephgrave, Rachel et al.·Medicina (Kaunas, Lithuania)·2024

This study surveyed 876 people with ME/CFS from 26 countries to understand how the condition affects their daily lives. People with ME/CFS reported very poor quality of life, with an average health rating of 36 out of 100. The most common problems were difficulty doing everyday activities (97%), pain (92%), and trouble with movement (83%).

Pain and Sensitization

Resonant breathing improves self-reported symptoms and wellbeing in people with Long COVID.

Polizzi, Jessica, Tosto-Mancuso, Jenna, Tabacof, Laura et al.·Frontiers in rehabilitation sciences·2024

This study looked at whether slow, controlled breathing (called resonant breathing) could help people with Long COVID feel better. Ninety-nine people with Long COVID tried a resonant breathing program and reported their symptoms before and after. Most people said they felt better overall, especially in areas like stress control, focus, breathing ability, and sleep quality.

Chronic Overlapping Pain Conditions in people with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): a sample from the Multi-site Clinical Assessment of ME/CFS (MCAM) study.

Fall, Elizabeth A, Chen, Yang, Lin, Jin-Mann S et al.·BMC neurology·2024

This study found that most people with ME/CFS (76%) also experience other chronic pain conditions, such as migraines, fibromyalgia, lower back pain, and irritable bowel syndrome. These overlapping conditions were much more common in ME/CFS patients compared to healthy people (only 17% had them). When patients had multiple pain conditions alongside their ME/CFS, their overall symptoms and quality of life were significantly worse, especially for women.

["The idea of rehabilitation will have to be completely rethought for this illness" - Qualitative results of an online survey on patients' experiences with inpatient rehabilitation for post COVID-19 condition (long COVID)].

Hammer, Sabine, Schmidt, Julia, Conrad, Annett et al.·Zeitschrift fur Evidenz, Fortbildung und Qualitat im Gesundheitswesen·2024

German researchers asked 1,191 long COVID patients about their experiences with inpatient rehabilitation programs. About half reported their health got worse during rehabilitation, mainly from exercise programs that were too intense. The study found that standard rehabilitation designed for other illnesses often doesn't work for long COVID patients with post-exertional malaise, and programs should instead focus on teaching patients how to pace their activities safely.