Analyzing the Interplay between COVID-19 Viral Load, Inflammatory Markers, and Lymphocyte Subpopulations on the Development of Long COVID

Abstract:

The global impact of the SARS-CoV-2 infection has been substantial, affecting millions of people. Long COVID, characterized by persistent or recurrent symptoms after acute infection, has been reported in over 40% of patients. Risk factors include age and female gender, and various mechanisms, including chronic inflammation and viral persistence, have been implicated in long COVID’s pathogenesis. However, there are scarce studies in which multiple inflammatory markers and viral load are analyzed simultaneously in acute infection to determine how they predict for long COVID at long-term follow-up. This study explores the association between long COVID and inflammatory markers, viral load, and lymphocyte subpopulation during acute infection in hospitalized patients to better understand the risk factors of this disease.
This longitudinal retrospective study was conducted in patients hospitalized with COVID-19 in northern Mexico. Inflammatory parameters, viral load, and lymphocyte subpopulation during the acute infection phase were analyzed, and long COVID symptoms were followed up depending on severity and persistence (weekly or monthly) and assessed 1.5 years after the acute infection.
This study analyzed 79 patients, among them, 41.8% presented long COVID symptoms, with fatigue being the most common (45.5%). Patients with long COVID had higher lymphocyte levels during hospitalization, and NK cell subpopulation levels were also associated with long COVID. ICU admission during acute COVID-19 was also linked to the development of long COVID symptoms.
Source: Rivera-Cavazos A, Luviano-García JA, Garza-Silva A, Morales-Rodríguez DP, Kuri-Ayache M, Sanz-Sánchez MÁ, Santos-Macías JE, Romero-Ibarguengoitia ME, González-Cantú A. Analyzing the Interplay between COVID-19 Viral Load, Inflammatory Markers, and Lymphocyte Subpopulations on the Development of Long COVID. Microorganisms. 2023; 11(9):2241. https://doi.org/10.3390/microorganisms11092241 https://www.mdpi.com/2076-2607/11/9/2241 (Full text)

Genetic Risk Factors for Severe and Fatigue Dominant Long COVID and Commonalities with ME/CFS Identified by Combinatorial Analysis

Abstract:

Background Long COVID is a debilitating chronic condition that has affected over 100 million people globally. It is characterized by a diverse array of symptoms, including fatigue, cognitive dysfunction and respiratory problems. Studies have so far largely failed to identify genetic associations, the mechanisms behind the disease, or any common pathophysiology with other conditions such as ME/CFS that present with similar symptoms.

Methods We used a combinatorial analysis approach to identify combinations of genetic variants significantly associated with the development of long COVID and to examine the biological mechanisms underpinning its various symptoms. We compared two subpopulations of long COVID patients from Sano Genetics’ Long COVID GOLD study cohort, focusing on patients with severe or fatigue dominant phenotypes. We evaluated the genetic signatures previously identified in an ME/CFS population against this long COVID population to understand similarities with other fatigue disorders that may be triggered by a prior viral infection. Finally, we also compared the output of this long COVID analysis against known genetic associations in other chronic diseases, including a range of metabolic and neurological disorders, to understand the overlap of pathophysiological mechanisms.

Results Combinatorial analysis identified 73 genes that were highly associated with at least one of the long COVID populations included in this analysis. Of these, 9 genes have prior associations with acute COVID-19, and 14 were differentially expressed in a transcriptomic analysis of long COVID patients. A pathway enrichment analysis revealed that the biological pathways most significantly associated with the 73 long COVID genes were mainly aligned with neurological and cardiometabolic diseases.

Expanded genotype analysis suggests that specific SNX9 genotypes are a significant contributor to the risk of or protection against severe long COVID infection, but that the gene-disease relationship is context dependent and mediated by interactions with KLF15 and RYR3.

Comparison of the genes uniquely associated with the Severe and Fatigue Dominant long COVID patients revealed significant differences between the pathways enriched in each subgroup. The genes unique to Severe long COVID patients were associated with immune pathways such as myeloid differentiation and macrophage foam cells. Genes unique to the Fatigue Dominant subgroup were enriched in metabolic pathways such as MAPK/JNK signaling. We also identified overlap in the genes associated with Fatigue Dominant long COVID and ME/CFS, including several involved in circadian rhythm regulation and insulin regulation. Overall, 39 SNPs associated in this study with long COVID can be linked to 9 genes identified in a recent combinatorial analysis of ME/CFS patient from UK Biobank.

Among the 73 genes associated with long COVID, 42 are potentially tractable for novel drug discovery approaches, with 13 of these already targeted by drugs in clinical development pipelines. From this analysis for example, we identified TLR4 antagonists as repurposing candidates with potential to protect against long term cognitive impairment pathology caused by SARS-CoV-2. We are currently evaluating the repurposing potential of these drug targets for use in treating long COVID and/or ME/CFS.

Conclusion This study demonstrates the power of combinatorial analytics for stratifying heterogeneous populations in complex diseases that do not have simple monogenic etiologies. These results build upon the genetic findings from combinatorial analyses of severe acute COVID-19 patients and an ME/CFS population and we expect that access to additional independent, larger patient datasets will further improve the disease insights and validate potential treatment options in long COVID.

Source: Krystyna TaylorMatthew PearsonSayoni DasJason SardellKarolina ChocianSteve Gardners. Genetic Risk Factors for Severe and Fatigue Dominant Long COVID and Commonalities with ME/CFS Identified by Combinatorial Analysis.

Utility of Serum Ferritin for Predicting Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in Patients with Long COVID

Abstract:

Objective: The most common symptom of post-acute coronavirus disease 2019 (COVID-19) is fatigue, and it potentially leads to myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS); however, a specific prognosticator is lacking. We aimed to elucidate the clinical characteristics of patients who developed ME/CFS after COVID-19.
Methods: In this retrospective observational study, patients who visited Okayama University Hospital for long COVID between February 2021 and March 2022 were investigated.
Results: Of the 234 patients, 139 (59.4%) had fatigue symptoms. Fifty patients with fatigue symptoms (21.4%) met the criteria for ME/CFS (ME/CFS group), while the other 89 patients did not (non-ME/CFS group); 95 patients had no fatigue complaints (no-fatigue group). Although the patients’ backgrounds were not significantly different between the three groups, the ME/CFS group presented the highest scores on the self-rating symptom scales, including the Fatigue Assessment Scale (FAS), EuroQol, and the Self-Rating Depression Scale (SDS). Furthermore, serum ferritin levels, which were correlated with FAS and SDS scores, were significantly higher in the ME/CFS group (193.0 μg/mL, interquartile range (IQR): 58.8–353.8) than in the non-ME/CFS group (98.2 μg/mL, 40.4–251.5) and no-fatigue group (86.7 μg/mL, 37.5–209.0), and a high serum ferritin level was prominent in female patients. Endocrine workup further showed that the ME/CFS group had higher thyrotropin levels but lower growth hormone levels in serum and that insulin-like growth factor-I levels were inversely correlated with ferritin levels (R = −0.328, p < 0.05).
Conclusions: Serum ferritin level is a possible predictor of the development of ME/CFS related to long COVID, especially in female patients.
Source: Yamamoto Y, Otsuka Y, Tokumasu K, Sunada N, Nakano Y, Honda H, Sakurada Y, Hasegawa T, Hagiya H, Otsuka F. Utility of Serum Ferritin for Predicting Myalgic Encephalomyelitis/Chronic Fatigue Syndrome in Patients with Long COVID. Journal of Clinical Medicine. 2023; 12(14):4737. https://doi.org/10.3390/jcm12144737 https://www.mdpi.com/2077-0383/12/14/4737 (Full text)

Fatigue presentation, severity, and related outcomes in a prospective cohort following post-COVID-19 hospitalization in British Columbia, Canada

Abstract:

Introduction: Increasing evidence on long-term health outcomes following SARS CoV-2 infection shows post-viral symptoms can persist for months. These symptoms are often consistent with those of Myalgic Encephalomyelitis or Chronic Fatigue Syndrome (ME/CFS). The aim of the present study was to examine the prevalence and outcome predictors of post-viral fatigue and related symptoms 3- and 6-months following symptom onset.

Methods: A prospective cohort of patients hospitalized with Coronavirus disease (COVID-19) (n = 88) were recruited from a Post-COVID-19 Respiratory Clinic (PCRC) in Vancouver, Canada to examine predictors of long-term fatigue and substantial fatigue. Multivariable mixed effects analyses examined the relationship between patient predictors, including pre-existing comorbidities, patient reported outcome measures, and fatigue and substantial fatigue at follow-up.

Results: The number of patients experiencing fatigue or substantial fatigue at 3 months post-infection were 58 (67%) and 14 (16%) respectively. At 6 months these numbers declined to 47 (60%) patients experiencing fatigue and 6 (6%) experiencing substantial fatigue. Adjusted analysis, for sex, age, and time, revealed the number of pre-existing comorbidities to be associated with fatigue (OR 2.21; 95% CI 1.09-4.49; 0.028) and substantial fatigue (OR 1.73; 95% CI 1.06-2.95; 0.033) at 3 months follow-up. Except for shortness of breath, self-care, and follow-up time, all follow-up variables were found to be associated with fatigue and substantial fatigue at 3 months.

Conclusion: Fatigue and substantial fatigue are common after COVID-19 infection but often diminish over time. A significant number of patients continue to exhibit long-term fatigue at 6 months follow-up. Further research is needed to clarify the causality of viral infections in the development and severity of fatigue as a symptom and in meeting post-viral fatigue syndrome or ME/CFS diagnostic criteria.

Source: Magel T, Meagher E, Boulter T, Albert A, Tsai M, Muñoz C, Carlsten C, Johnston J, Wong AW, Shah A, Ryerson C, Mckay RJ, Nacul L. Fatigue presentation, severity, and related outcomes in a prospective cohort following post-COVID-19 hospitalization in British Columbia, Canada. Front Med (Lausanne). 2023 Jun 29;10:1179783. doi: 10.3389/fmed.2023.1179783. PMID: 37457578; PMCID: PMC10344448. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10344448/ (Full text)

Fatigue in Post-Acute Sequelae of Coronavirus Disease 2019

Abstract:

Fatigue from post-acute sequelae of coronavirus disease 2019 is a complex constellation of symptoms that could be driven by a wide spectrum of underlying etiologies. Despite this, there seems to be hope for treatment plans that focus on addressing possible etiologies and creating a path to improving quality of life and a paced return to activity.

Source: Abbott Z, Summers W, Niehaus W. Fatigue in Post-Acute Sequelae of Coronavirus Disease 2019. Phys Med Rehabil Clin N Am. 2023 Aug;34(3):607-621. doi: 10.1016/j.pmr.2023.04.006. Epub 2023 Apr 24. PMID: 37419535; PMCID: PMC10123359. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10123359/ (Full text)

Determinants of the Onset and Prognosis of the Post-COVID-19 Condition: A 2-Year Prospective Cohort Study

Abstract:

Background: At least 5-10% of subjects surviving COVID-19 develop the post-COVID-19 condition (PCC) or “Long COVID”. The clinical presentation of PCC is heterogeneous, its pathogenesis is being deciphered, and objective, validated biomarkers are lacking. It is unknown if PCC is a single entity or a heterogeneous syndrome with overlapping pathophysiological basis. In a large crossectional evaluation, the RECOVER study in the US identified four clusters of subjects with PCC according to their presenting symptoms. The long-term clinical implications of PCC remain unknown.

Methods: We conducted a 2-year prospective cohort study of subjects surviving COVID-19, including individuals fulfilling the WHO PCC definition and subjects with full clinical recovery. We systematically collected post-COVID-19 symptoms using prespecified questionnaires and performed additional diagnostic imaging tests when needed. Factors associated with PCC were identified and modeled using logistic regression. Unsupervised clustering analysis was used to group subjects with PCC according to their presenting symptoms. Factors associated with PCC recovery were modelled using a direct acyclic graph approach.

Findings: The study included 548 individuals, 341 with PCC, followed for a median of 23 months (IQR 16·5 – 23·5), and 207 subjects fully recovered. In the model with the best fit, subjects who were male and had tertiary studies were less likely to develop PCC, whereas a history of headache, or presence of tachycardia, fatigue, neurocognitive and neurosensitive complaints and dyspnea at COVID-19 diagnosis predicted the development of PCC. The cluster analysis revealed the presence of three symptom clusters with an additive number of symptoms. Only 26 subjects (7·6%) recovered from PCC during follow-up; almost all of them (n=24) belonged to the less symptomatic cluster A, dominated mainly by fatigue. Recovery from PCC was more likely in subjects who were male, required ICU admission, or had cardiovascular comorbidities, hyporexia and/or smell/taste alterations during acute COVID-19. Subjects presenting with muscle pain, impaired attention, dyspnea, or tachycardia, conversely, were less likely to recover from PCC.

Interpretation: Preexisting medical and socioeconomic factors, as well as acute COVID-19 symptoms, predict the development of and recovery from the PCC. Recovery is extremely rare during the first 2 years, posing a major challenge to healthcare systems.

Source: Mateu, Lourdes and Tebe, Cristian and Loste, Cora and Santos, José Ramón and Lladós, Gemma and López, Cristina and España-Cueto, Sergio and Toledo, Ruth and Font, Marta and Chamorro, Anna and Muñoz-López, Francisco and Nevot, Maria and Vallejo, Nuria and Teis, Albert and Puig, Jordi and Fumaz, Carmina Rodríguez and Muñoz-Moreno, José Antonio and Prats, Anna and Estany-Quera, Carla and Coll-Fernández, Roser and Herrero, Cristina and Casares, Patricia and Garcia, Anna and Paredes, Roger and Clotet, Bonaventura and Massanella, Marta, Determinants of the Onset and Prognosis of the Post-COVID-19 Condition: A 2-Year Prospective Cohort Study. Available at SSRN: https://ssrn.com/abstract=4505315 or http://dx.doi.org/10.2139/ssrn.4505315 (Full text available as PDF file)

Trajectory of Post-COVID Self-Reported Fatigue and Dyspnoea in Individuals Who Had Been Hospitalized by COVID-19: The LONG-COVID-EXP Multicenter Study

Abstract:

Fatigue and dyspnoea are common post-COVID symptoms. The aim of this study was to apply Sankey plots and exponential bar plots for visualizing the evolution and trajectory of post-COVID fatigue and dyspnoea symptoms in a cohort of previously hospitalized COVID-19 survivors. A total of 1266 previously hospitalized patients due to COVID-19 participated in this multicentre study. They were assessed at hospital admission (T0), 8.4 months (T1), 13.2 months (T2) and 18.3 months (T3) after hospital discharge and were asked about the presence of self-reported fatigue or dyspnoea symptoms.
Fatigue was defined as a self-perceived feeling of constant tiredness and/or weakness whereas dyspnoea was defined as a self-perceived feeling of shortness of breath at rest. We specifically asked for fatigue and dyspnoea that participants attributed to the infection. Clinical/hospitalization data were collected from hospital medical records.
The prevalence of post-COVID fatigue was 56.94% (n = 721) at T1, 52.31% (n = 662) at T2 and 42.66% (n = 540) at T3. The prevalence of dyspnoea at rest decreased from 28.71% (n = 363) at hospital admission (T0), to 21.29% (n = 270) at T1, to 13.96% (n = 177) at T2 and 12.04% (n = 153) at T3. The Sankey plots revealed that 469 (37.08%) and 153 (12.04%) patients exhibited fatigue and dyspnoea at all follow-up periods.
The recovery exponential curves show a decreased prevalence trend, showing that fatigue and dyspnoea recover the following three years after hospitalization. The regression models revealed that the female sex and experiencing the symptoms (e.g., fatigue, dyspnoea) at T1 were factors associated with the presence of post-COVID fatigue or dyspnoea at T2 and T3.
The use of Sankey plots shows a fluctuating evolution of post-COVID fatigue and dyspnoea during the first two years after infection. In addition, exponential bar plots revealed a decreased prevalence of these symptoms during the first years after. The female sex is a risk factor for the development of post-COVID fatigue and dyspnoea.
Source:Fernández-de-las-Peñas C, Cancela-Cilleruelo I, Rodríguez-Jiménez J, Fuensalida-Novo S, Martín-Guerrero JD, Pellicer-Valero OJ, de-la-Llave-Rincón AI. Trajectory of Post-COVID Self-Reported Fatigue and Dyspnoea in Individuals Who Had Been Hospitalized by COVID-19: The LONG-COVID-EXP Multicenter Study. Biomedicines. 2023; 11(7):1863. https://doi.org/10.3390/biomedicines11071863 https://www.mdpi.com/2227-9059/11/7/1863 (Full text)

The potential role of Rhodiola rosea L. extract WS® 1375 for patients with post-COVID-19 fatigue

Abstract:

Fatigue and physical exhaustion are the dominant symptoms of post-coronavirus (COVID-19) conditions that might even develop after only mild acute disease. Post-acute infection syndromes have been observed after various infections, e.g., Coxiella burnetii, Ebola, Dengue, Polio, severe acute respiratory syndrome (SARS), Chikungunya, West Nile Virus, Borrelia, or Giardina lamblia. The similarities in symptoms and courses suggest a high likelihood of common pathogenetic pathways, including persistent infection, autoimmune reactions, dysregulation of the microbiome, inability to repair tissue damage, or endothelial dysfunction.

Some herbal drugs, so-called adaptogens, exert effects resulting in an increase in the resistance or regulatory potential of organisms against biological, chemical and physical burden or stress. Therefore, it seems possible that adaptogens can be helpful in cases of post-COVID-19 symptoms. One of these adaptogens is Rhodiola rosea L. The proprietary ethanolic extract made from roots and rhizomes of Rhodiola rosea WS® 1375 has been reported to modulate neuroinflammation in response to stress stimuli in preclinical models. Moreover, it activated the synthesis or resynthesis of adenosine triphosphate (ATP) in skeletal muscle mitochondria and counteracted muscle fatigue.

In three clinical trials with subjects suffering from burnout symptoms, prolonged or chronic fatigue symptoms or life-stress symptoms, clinically relevant improvements of fatigue and exhaustion were reported over 4 to 12 weeks of treatment at a very favorable tolerability and safety profile in heterogeneous patient populations. In conclusion, Rhodiola rosea extract WS® 1375 has a promising pharmacological and therapeutic profile for the treatment of fatigue and physical exhaustion associated with post-COVID-19 conditions.

Source: Wegener T, Edwards D, Kasper S. The potential role of Rhodiola rosea L. extract WS® 1375 for patients with post-COVID-19 fatigue. hb TIMES Schw Aerztej. 2023;8(1):56-61. doi:10.36000/hbT.2023.09.001 https://schw-aerztej.healthbooktimes.org/article/74319-the-potential-role-of-rhodiola-rosea-l-extract-ws-1375-for-patients-with-post-covid-19-fatigue (Full text)

Long COVID Clinical Phenotypes Up to Six Months After Infection Identified by Latent Class Analysis of Self-Reported Symptoms

Abstract:

Background: The prevalence, incidence, and interrelationships of persistent symptoms after SARS-CoV-2 infection (Long COVID) vary. There are limited data on specific phenotypes of persistent symptoms. Using latent class analysis (LCA) modeling, we sought to identify whether specific phenotypes of COVID-19 were present three months and six months after acute infection.

Methods: This was a multicenter, prospective study of symptomatic adults tested for SARS-CoV-2 with prospectively collected data on general symptoms and fatigue-related symptoms up to six-months post-diagnosis. Using LCA, we identified symptomatically homogenous groups among participants with COVID-19 (COVID-positive) and among others without COVID-19 (COVID-negative) at each time period for both general and fatigue-related symptoms.

Results: Among 5,963 baseline participants (4,504 COVID-positive and 1,459 COVID-negative), 4,056 had three-month and 2,856 had six-month data at the time of analysis. We identified four distinct phenotypes of post-COVID conditions at three- and six-months for both general and fatigue-related symptoms; minimal symptom groups represented 70% of participants at three and six months. When compared with the COVID-negative cohort, COVID-positive participants had higher occurrence of loss of taste and smell, as well cognition problems. There was substantial class-switching over time; those in one symptom class at three months were equally likely to remain or enter a new phenotype at six months.

Conclusions: We identified distinct classes of post-COVID phenotypes for general and fatigue-related symptoms. Most participants had minimal or no symptoms at three and six months follow-up. Significant proportions of participants changed symptom groups over time, suggesting that symptoms present during the acute illness may differ from prolonged symptoms and that post-COVID conditions may have a more dynamic nature than previously recognized.

Source: Michael Gottlieb, MD and others, Long COVID Clinical Phenotypes Up to Six Months After Infection Identified by Latent Class Analysis of Self-Reported Symptoms, Open Forum Infectious Diseases, 2023;, ofad277, https://doi.org/10.1093/ofid/ofad277 (Full text available as PDF file)

Long-COVID: A Chronic Fatigue Condition: Case Report

Abstract:

For the growing number of patients suffering from post-COVID-19 syndrome, there is little definitive guidance for treatment protocols or prognosis. Neurologic manifestations following acute COVID-19 infection are continually surfacing in the literature, with fatigue being the most common persistent symptom.

This case study follows a 44-year-old female experiencing debilitating fatigue and neurologic symptoms persisting after the resolution of an acute SARS-COV-2 infection. The complex medical history of this patient, including past Epstein-Barr Virus (EBV) infection and Myalgic Encephalomyelitis, commonly known as Chronic Fatigue Syndrome, suggests a potential predisposition for the development of neurologic long-COVID.

Through investigation of current research and treatment responses, this case report aims to gain an understanding of the complicated nature of this illness, and to propose treatments that address this specific subset of post-acute SARS-COV-2 sequelae.

Source: Lavelle , M., & Brusewitz , N. D. J. (2023). Long-COVID: A Chronic Fatigue Condition: Case Report. Journal of Complementary and Alternative Medical Research22(3), 1–7. https://doi.org/10.9734/jocamr/2023/v22i3457 http://stmlibrary.uk/id/eprint/2217/1/Lavelle2232023JOCAMR100443.pdf (Full text)