ArticleEuropean journal of neurology2022
Myopathy as a cause of fatigue in long-term post-COVID-19 symptoms: Evidence of skeletal muscle histopathology.
Article in European journal of neurology, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 70 papers, 1 of them a synthesis that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
70 citing papers in PubMed, 1 synthesis or guideline pooled it, 110 citations in OpenAlex.
- Pathophysiological mechanisms of post-exertional malaise: an integrative analysis based on the metabolism-immune-neuro interaction model.Frontiers in immunology · 2026Pooled it
- Altered muscle transcriptome as molecular basis of long-term muscle weakness in survivors from critical illness.Intensive care medicine · 2025Trial
- Effects of a symptom-titrated exercise program on fatigue and quality of life in people with post-COVID condition - a randomized controlled trial.Scientific reports · 2024Trial
- Functional Limitations and Exercise Intolerance in Patients With Post-COVID Condition: A Randomized Crossover Clinical Trial.JAMA network open · 2024Trial
- Skeletal muscle properties in long COVID and ME/CFS differ from those induced by bed rest.Nature communications · 2026Article
- A systematic scoping review and conceptual analysis of new-onset fibromyalgia manifestations after non-hospitalized COVID-19: empirics, definitions, methodologies, pathophysiology, mapping of literature, and knowledge gaps.Journal of translational medicine · 2026Article
- Current status and future perspectives on the mechanistic and pathophysiological understanding of long COVID.Communications medicine · 2026Article
- Associations between heart rate and physical activity in people with post-COVID-19 condition accounting for myalgic encephalomyelitis/chronic fatigue syndrome symptoms.Journal of rehabilitation medicine · 2026Observational
- Virus-induced endothelial senescence as a cause and driving factor for ME/CFS and long COVID: mediated by a dysfunctional immune system.Cell death & disease · 2026Review
- The Post-COVID syndrome caused by excessive inflammation: pathogenesis, potential targets and therapeutic agents.Frontiers in pharmacology · 2026Review
- Mechanisms and impact of long COVID: pathophysiology, neuropsychiatric effects and vaccination.Frontiers in immunology · 2026Review
- Assessment of Bone Mineral Density, Total Body Composition and Joint Integrity in Long COVID: A 12-Month Longitudinal Feasibility Study.Journal of clinical medicine · 2025Article
- Soluble IL-2R: A potential therapeutic target for mitochondrial dysfunction in post-COVID fatigue syndrome.Clinical and translational medicine · 2025Article
- Post-COVID-19 condition: clinical phenotypes, pathophysiological mechanisms, pathology, and management strategies.The Journal of pathology · 2025Review
- Histopathological analysis of respiratory muscles in patients with acute COVID-19 infection.Cell and tissue research · 2025Article
- Reply to: Should we be careful with exercise in post-exertional malaise after Long COVID?Nature communications · 2025Article
- Reply: Muscle abnormalities in Long COVID.Nature communications · 2025Article
- Differential Fatigue Profile in Patients with Post-COVID Condition, Fibromyalgia, and Multiple Sclerosis.Journal of clinical medicine · 2025Article
- Key Pathophysiological Role of Skeletal Muscle Disturbance in Post COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS): Accumulated Evidence.Journal of cachexia, sarcopenia and muscle · 2025Review
- Article
10 more citing papers are in PubMed but not listed here.
Corrections and comments
- Commented on by
- Commented on by
Authors and funding
9 authors at 4 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
background and purposeAmong post-COVID-19 symptoms, fatigue is reported as one of the most common, even after mild acute infection, and as the cause of fatigue, myopathy diagnosed by electromyography has been proposed in previous reports. This study aimed to explore the histopathological changes in patients with post-COVID-19 fatigue.
methodsSixteen patients (mean age = 46 years) with post-COVID-19 complaints of fatigue, myalgia, or weakness persisting for up to 14 months were included. In all patients, quantitative electromyography and muscle biopsies analyzed with light and electron microscopy were taken.
resultsMuscle weakness was present in 50% and myopathic electromyography in 75%, and in all patients there were histological changes. Muscle fiber atrophy was found in 38%, and 56% showed indications of fiber regeneration. Mitochondrial changes, comprising loss of cytochrome c oxidase activity, subsarcollemmal accumulation, and/or abnormal cristae, were present in 62%. Inflammation was found in 62%, seen as T lymphocytes and/or muscle fiber human leukocyte antigen ABC expression. In 75%, capillaries were affected, involving basal lamina and cells. In two patients, uncommon amounts of basal lamina were found, not only surrounding muscle fibers but also around nerves and capillaries.
conclusionsThe wide variety of histological changes in this study suggests that skeletal muscles may be a major target of SARS-CoV-2, causing muscular post-COVID-19 symptoms. The mitochondrial changes, inflammation, and capillary injury in muscle biopsies can cause fatigue in part due to reduced energy supply. Because most patients had mild-moderate acute affection, the new variants that might cause less severe acute disease could still have the ability to cause long-term myopathy.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.