Long-term neuromuscular consequences of SARS-Cov-2 and their similarities with myalgic encephalomyelitis/chronic fatigue syndrome: results of the retrospective CoLGEM study

Abstract

Background Patients with long-COVID often complain of continuous fatigue, myalgia, sleep problems, cognitive dysfunction, and post-exertional malaise. No data are available on EMG recording of evoked myopotentials (M-waves) or exercise-induced alterations in long-COVID patients, providing evidence of muscle membrane fatigue. Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) develops in more than half of patients after an infectious disease, particularly viral diseases. A large proportion (around 70%) of these patients have neuromuscular disorders with M-wave alterations during and after exercise. Our hypothesis was that M-wave alterations would be also found in long-COVID patients, in association with neuromuscular symptoms, similar to ME/CFS. Methods This retrospective observational ColGEM (Covid LonG Encéphalomyelite Myalgique) study compared 59 patients with long-COVID and 55 ME/CFS patients with a history of severe infection who presented before the COVID pandemic. All of these patients underwent the same protocol consisting of a questionnaire focusing on neural and neuromuscular disorders and M-wave recording in the rectus femoris muscle before, during, and 10 min after a progressive cycling exercise. Maximal handgrip strength (MHGS) and maximal exercise power were also measured. The frequency of symptoms and magnitude of M-wave changes in the two groups were compared using non-parametric and parametric tests. Results The frequency of fatigue, myalgia, sleep problems, cognitive dysfunction, and post-exertional malaise as well as the magnitude of exercise-induced M-wave alterations were the same in the two groups. By contrast, digestive problems were less present in long-COVID. M-wave alterations were greater in ME/CFS patients as in those with long-COVID when the highest muscle strength and highest exercise performance were measured. Conclusions These high clinical and biological similarities between long-COVID and ME/CFS support the hypothesis that SARS-Cov-2 infection can cause ME/CFS symptoms. Trial registration Registered retrospectively.

Orthostatic tachycardia after covid-19

“…If tolerated (but not otherwise), the patient should gradually increase the length and intensity of activity. However, as covered in a previous article in this series,1 worsening of symptoms following physical or mental activity is a common feature of long covid313940 and necessitates caution along with careful pacing, starting with low level gentle exercise. Some patients may require pharmacological measures in combination with conservative measures to engage in any physical activity 27…”

Post-COVID syndrome is associated with capillary alterations, macrophage infiltration and distinct transcriptomic signatures in skeletal muscles

“…The pathomechanisms behind post-COVID Syndrome (PCS), Post-acute sequelae of SARS-CoV-2 infection or long COVID, are not well understood, plausibly because the manifestations and causes are diverse and semantically diffuse, thus hampering comparative descriptive and mechanistic studies. Similar to post-SARS-syndrome reported after the SARS epidemic in [2003][2004] (12,13), many clinicians noticed that some prevailing symptoms of PCS were reminiscent of chronic fatigue syndrome (ME/CFS) (14)(15)(16)(17). This syndrome is entirely based on clinical criteria and exclusion of other diagnoses, plausibly consisting of different causal entities resulting in a similar phenotype, which is centered around a chronic fatigue aggravated by physical and/or mental activity and accompanied by other symptoms (e.g.…”

No Causal Effects Detected in COVID-19 and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Two Sample Mendelian Randomization Study

“…This is still a controversial question and needs further research to provide an exact answer. The clinical features between Long COVID and ME/CFS are highly similar, and both include persistent fatigue, sleep problems, muscle aches, cognitive dysfunction and post-exercise discomfort, and in an observational trial prior to the COVID-19 pandemic, Long COVID and ME/CFS patients showed the same biological characteristics of these symptoms [42]. It is because of the high degree of symptom similarity between post-COVID and ME/CFS that a causal relationship between them has been sought by scholars.…”