Inflammation-type dysbiosis of the oral microbiome associates with the duration of COVID-19 symptoms and long COVID

Abstract:

In the COVID-19 pandemic, caused by SARS-CoV-2, many individuals experience prolonged symptoms, termed long-lasting COVID-19 symptoms (long COVID). Long COVID is thought to be linked to immune dysregulation due to harmful inflammation, with the exact causes being unknown. Given the role of the microbiome in mediating inflammation, we aimed to examine the relationship between the oral microbiome and the duration of long COVID symptoms.

Tongue swabs were collected from patients presenting with COVID-19 symptoms. Confirmed infections were followed until resolution of all symptoms. Bacterial composition was determined by metagenomic sequencing. We used random forest modeling to identify microbiota and clinical covariates that are associated with long COVID symptoms. Of the patients followed, 63% developed ongoing symptomatic COVID-19 and 37% went on to long COVID.

Patients with prolonged symptoms had significantly higher abundances of microbiota that induced inflammation, such as members of the genera Prevotella and Veillonella, which, of note, are species that produce LPS. The oral microbiome of patients with long COVID was similar to that of patients with chronic fatigue syndrome.

Altogether, our findings suggest an association with the oral microbiome and long COVID, revealing the possibility that dysfunction of the oral microbiome may have contributed to this draining disease.

Source: Haran JP, Bradley E, Zeamer AL, Cincotta L, Salive MC, Dutta P, Mutaawe S, Anya O, Meza-Segura M, Moormann AM, Ward DV, McCormick BA, Bucci V. Inflammation-type dysbiosis of the oral microbiome associates with the duration of COVID-19 symptoms and long COVID. JCI Insight. 2021 Oct 22;6(20):e152346. doi: 10.1172/jci.insight.152346. PMID: 34403368; PMCID: PMC8564890. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8564890/ (Full text)

Risk Factors for Long COVID in Older Adults

Abstract:

As time has passed following the COVID-19 pandemic, individuals infected with SARS-CoV-2 have gradually exhibited a variety of symptoms associated with long COVID in the postacute phase of infection. Simultaneously, in many countries worldwide, the process of population aging has been accelerating. Within this context, the elderly population has not only become susceptible and high-risk during the acute phase of COVID-19 but also has considerable risks when confronting long COVID.
Elderly individuals possess specific immunological backgrounds, and during the process of aging, their immune systems can enter a state known as “immunosenescence”. This further exacerbates “inflammaging” and the development of various comorbidities in elderly individuals, rendering them more susceptible to long COVID. Additionally, long COVID can inflict both physical and mental harm upon elderly people, thereby reducing their overall quality of life. Consequently, the impact of long COVID on elderly people should not be underestimated.
This review seeks to summarize the infection characteristics and intrinsic factors of older adults during the COVID-19 pandemic, with a focus on the physical and mental impact of long COVID. Additionally, it aims to explore potential strategies to mitigate the risk of long COVID or other emerging infectious diseases among older adults in the future.
Source: Hu Y, Liu Y, Zheng H, Liu L. Risk Factors for Long COVID in Older Adults. Biomedicines. 2023; 11(11):3002. https://doi.org/10.3390/biomedicines11113002 https://www.mdpi.com/2227-9059/11/11/3002 (Full text)

Determinants of the onset and prognosis of the post-COVID-19 condition: a 2-year prospective observational 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. The large US RECOVER study identified four clusters of subjects with PCC according to their presenting symptoms. However, 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 modelled 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, are associated with 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 L, Tebe C, Loste C, Santos JR, Lladós G, López C, España-Cueto S, Toledo R, Font M, Chamorro A, Muñoz-López F, Nevot M, Vallejo N, Teis A, Puig J, Fumaz CR, Muñoz-Moreno JA, Prats A, Estany-Quera C, Coll-Fernández R, Herrero C, Casares P, Garcia A, Clotet B, Paredes R, Massanella M. Determinants of the onset and prognosis of the post-COVID-19 condition: a 2-year prospective observational cohort study. Lancet Reg Health Eur. 2023 Sep 5;33:100724. doi: 10.1016/j.lanepe.2023.100724. PMID: 37954002; PMCID: PMC10636281. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10636281/ (Full text)

Predictive models of long COVID

Abstract:

Background: The cause and symptoms of long COVID are poorly understood. It is challenging to predict whether a given COVID-19 patient will develop long COVID in the future.

Methods: We used electronic health record (EHR) data from the National COVID Cohort Collaborative to predict the incidence of long COVID. We trained two machine learning (ML) models – logistic regression (LR) and random forest (RF). Features used to train predictors included symptoms and drugs ordered during acute infection, measures of COVID-19 treatment, pre-COVID comorbidities, and demographic information. We assigned the ‘long COVID’ label to patients diagnosed with the U09.9 ICD10-CM code. The cohorts included patients with (a) EHRs reported from data partners using U09.9 ICD10-CM code and (b) at least one EHR in each feature category. We analysed three cohorts: all patients (n = 2,190,579; diagnosed with long COVID = 17,036), inpatients (149,319; 3,295), and outpatients (2,041,260; 13,741).

Findings: LR and RF models yielded median AUROC of 0.76 and 0.75, respectively. Ablation study revealed that drugs had the highest influence on the prediction task. The SHAP method identified age, gender, cough, fatigue, albuterol, obesity, diabetes, and chronic lung disease as explanatory features. Models trained on data from one N3C partner and tested on data from the other partners had average AUROC of 0.75.

Interpretation: ML-based classification using EHR information from the acute infection period is effective in predicting long COVID. SHAP methods identified important features for prediction. Cross-site analysis demonstrated the generalizability of the proposed methodology.

Source: Antony B, Blau H, Casiraghi E, Loomba JJ, Callahan TJ, Laraway BJ, Wilkins KJ, Antonescu CC, Valentini G, Williams AE, Robinson PN, Reese JT, Murali TM; N3C consortium. Predictive models of long COVID. EBioMedicine. 2023 Oct;96:104777. doi: 10.1016/j.ebiom.2023.104777. Epub 2023 Sep 4. PMID: 37672869; PMCID: PMC10494314. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10494314/ (Full text)

Habitual short sleepers with pre-existing medical conditions are at higher risk of Long COVID

Abstract:

STUDY OBJECTIVES: Preliminary evidence suggests that the risk of Long COVID is higher among people with pre-existing medical conditions. Based on its proven adjuvant role in immunity, habitual sleep duration may alter the risk for developing Long COVID. The objective of this study was to determine whether the odds of Long COVID are higher amongst those with pre-existing medical conditions, and whether the strength of this association varies by habitual sleep duration.

METHODS: Using data from 13,461 respondents from 16 countries who participated in the 2021 survey based International COVID Sleep Study II (ICOSS II), we studied the associations between habitual sleep duration, pre-existing medical conditions, and Long COVID.

RESULTS: Of 2,508 individuals who had COVID-19, 61% reported at least one Long COVID symptom. Multivariable logistic regression analysis showed that the risk of having Long COVID was 1.8-fold higher for average-length sleepers (6-9h/night) with pre-existing medical conditions compared to those without pre-existing medical conditions [aOR 1.84 (1.18-2.90), P=0.008]. The risk of Long COVID was 3-fold higher for short sleepers with pre-existing medical conditions [aOR 2.95 (1.04-8.4), P=0.043] and not significantly higher for long sleepers with pre-existing conditions [aOR 2.11 (0.93-4.77), P=0.073] compared to average-length sleepers without pre-existing conditions.

CONCLUSIONS: Habitual short nighttime sleep duration exacerbated the risk of Long COVID in individuals with pre-existing conditions. Restoring nighttime sleep to average duration represents a potentially modifiable behavioral factor to lower the odds of Long COVID for at-risk patients.

Source: Linor Berezin, MD, et al. Habitual short sleepers with pre-existing medical conditions are at higher risk of Long COVID. Journal of Clinical Sleep Medicine, Articles in Advance. https://jcsm.aasm.org/doi/pdf/10.5664/jcsm.10818 (Full text)

THU581 Possible Markers For Myalgic Encephalomyelitis / Chronic Fatigue Syndrome Developed In Long Covid: Utility Of Serum Ferritin And Insulin-like Growth Factor-I

Abstract:

Almost three years have passed since coronavirus disease 2019 (COVID-19) pandemic broke out, and along with the number of acute COVID-19 patients, the number of patients suffering from chronic prolonged symptoms after COVID-19, long COVID, or post COVID-19 condition, has also increased.

We established an outpatient clinic specialized for COVID-19 after care (CAC) in Okayama University Hospital in Japan in February 2021. Our recent study has revealed that the most common symptom is “fatigue”, a part of which potentially may develop into myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). However, the pathogenesis and specific prognosticator have yet to be elucidated. The aim of this study was to elucidate the clinical characteristics of patients who developed ME/CFS after COVID-19.

This retrospective observational study investigated the patients who visited our CAC outpatient clinic between February 2021 and March 2022. Of the 234 patients, 139 (59.4%) had fatigue symptoms, of whom 50 (21.4%) met the criteria for ME/CFS (ME/CFS group), while other 89 did not (non-ME/CFS group); 95 patients had no fatigue complaints (no-fatigue group). Although the patients’ backgrounds were not significantly different among 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 Self-Rating Depression Scale (SDS).

Of note, serum ferritin levels, which were correlated to FAS and SDS scores, were significantly higher in the ME/CFS group (193.0 μg/mL; interquartile range (IQR), 58.8-353.8) than those of non-ME/CFS (98.2 μg/mL; 40.4-251.5) and no-fatigue (86.7 μg/mL; 37.5-209.0) groups, and this trend was prominent in the female patients. Endocrine workup further showed that the ME/CFS group had higher thyrotropin levels but lower growth hormone levels in the serum, and that insulin-like growth factor (IGF)-I levels were inversely correlated with ferritin levels (R = -0.328, p < 0.05).

Collectively, we revealed that serum ferritin levels could be a possible predictor for developing ME/CFS related to long COVID, especially in female patients. Earlier studies have suggested that hyperferritinemia is a clinical feature in the patients of long COVID, in which hepcidin-like effects could also be involved. Our present study also uncovered a relationship between hyperferrinemia and endocrine disorders among patients developing ME/CFS after COVID-19, although further investigations are necessary to understand the characteristics of ferritin metabolism.

Presentation: Thursday, June 15, 2023

Source: Yukichika Yamamoto, Yuki Otsuka, Kazuki Tokumasu, Naruhiko Sunada, Yasuhiro Nakano, Hiroyuki Honda, Yasue Sakurada, Toru Hasegawa, Hideharu Hagiya, Fumio Otsuka, THU581 Possible Markers For Myalgic Encephalomyelitis / Chronic Fatigue Syndrome Developed In Long Covid: Utility Of Serum Ferritin And Insulin-like Growth Factor-I, Journal of the Endocrine Society, Volume 7, Issue Supplement_1, October-November 2023, bvad114.1370, https://doi.org/10.1210/jendso/bvad114.1370 (Full text available as PDF file)

Is Pulmonary Involvement a Distinct Phenotype of Post-COVID-19?

Abstract:

Background: COVID-19 infection often provokes symptoms lasting many months: most commonly fatigue, dyspnea, myalgia and mental distress symptoms. In this study, we searched for clinical features of post-COVID-19 condition (PCC) and differences between patients with and without pulmonary involvement.
Methods: A total of 282 patients with a mean age of 57 years (SD +/− 12 years) underwent assessment up to 12 weeks after COVID-19 recovery. The course of acute disease, past medical history and clinical symptoms were gathered; pulmonary function tests were performed; radiographic studies were assessed and follow-up examinations were conducted. Patients with and without detectable pulmonary lesions were divided into separate groups.
Results: Patients within the pulmonary group were more often older (59 vs. 51 y.o.; p < 0.001) males (p = 0.002) that underwent COVID-19-related hospitalization (p < 0.001) and were either ex- or active smokers with the median of 20 pack-years. We also managed to find correlations with hypertension (p = 0.01), liver failure (p = 0.03), clinical symptoms such as dyspnea (p < 0.001), myalgia (p = 0.04), headache (p = 0.009), sleeplessness (p = 0.046), pulmonary function tests (such as FVC, TLCO, RV and TLC; p < 0.001) and several basic laboratory tests (D-dimer, cardiac troponin, WBC, creatinine and others).
Conclusions: Our results indicate that initial pulmonary involvement alters the PCC, and it can be used to individualize clinical approaches.
Source: Bartczak KT, Miłkowska-Dymanowska J, Pietrusińska M, Kumor-Kisielewska A, Stańczyk A, Majewski S, Piotrowski WJ, Lipiński C, Wawrocki S, Białas AJ. Is Pulmonary Involvement a Distinct Phenotype of Post-COVID-19? Biomedicines. 2023; 11(10):2694. https://doi.org/10.3390/biomedicines11102694 https://www.mdpi.com/2227-9059/11/10/2694 (Full text)

15-month post-COVID syndrome in outpatients: Attributes, risk factors, outcomes, and vaccination status – longitudinal, observational, case-control study

Abstract:

Background: While the short-term symptoms of post-COVID syndromes (PCS) are well-known, the long-term clinical characteristics, risk factors and outcomes of PCS remain unclear. Moreover, there is ongoing discussion about the effectiveness of post-infection vaccination against severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) to aid in PCS recovery.

Methods: In this longitudinal and observational case-control study we aimed at identifying long-term PCS courses and evaluating the effects of post-infection vaccinations on PCS recovery. Individuals with initial mild COVID-19 were followed for a period of 15 months after primary infection. We assessed PCS outcomes, distinct symptom clusters (SC), and SARS-CoV-2 immunoglobulin G (IgG) levels in patients who received SARS-CoV-2 vaccination, as well as those who did not. To identify potential associating factors with PCS, we used binomial regression models and reported the results as odds ratios (OR) with 95% confidence intervals (95%CI).

Results: Out of 958 patients, follow-up data at 15 month after infection was obtained for 222 (23.2%) outpatients. Of those individuals, 36.5% (81/222) and 31.1% (69/222) were identified to have PCS at month 10 and 15, respectively. Fatigue and dyspnea (SC2) rather than anosmia and ageusia (SC1) constituted PCS at month 15. SARS-CoV-2 IgG levels were equally distributed over time among age groups, sex, and absence/presence of PCS. Of the 222 patients, 77.0% (171/222) were vaccinated between 10- and 15-months post-infection, but vaccination did not affect PCS recovery at month 15. 26.3% of unvaccinated and 25.8% of vaccinated outpatients improved from PCS (p= .9646). Baseline headache (SC4) and diarrhoea (SC5) were risk factors for PCS at months 10 and 15 (SC4: OR 1.85 (95%CI 1.04-3.26), p=.0390; SC5: OR 3.27(95%CI 1.54-6.64), p=.0009).

Conclusion: Based on the specific symptoms of PCS our findings show a shift in the pattern of recovery. We found no effect of SARS-CoV-2 vaccination on PCS recovery and recommend further studies to identify predicting biomarkers and targeted PCS therapeutics.

Source: Augustin M, Stecher M, Wüstenberg H, Di Cristanziano V, Sandaradura de Silva U, Picard LK, Pracht E, Rauschning D, Gruell H, Klein F, Wenisch C, Hallek M, Schommers P, Lehmann C. 15-month post-COVID syndrome in outpatients: Attributes, risk factors, outcomes, and vaccination status – longitudinal, observational, case-control study. Front Immunol. 2023 Sep 12;14:1226622. doi: 10.3389/fimmu.2023.1226622. PMID: 37781408; PMCID: PMC10540070. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10540070/ (Full text)

The Long Road of Long COVID: Specific Considerations for the Allergist and Immunologist

Abstract:

Long COVID (coronavirus disease 2019) syndrome, also known as post-acute sequelae of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, is a new disorder that can develop after an acute infection with the SARS-CoV-2 virus. The condition is characterized by multiorgan system involvement with a wide range of symptoms that can vary in severity from mild to debilitating.

Some of the common symptoms associated with long COVID syndrome include cardiovascular issues such as heart palpitations and chest pain; thrombotic events (eg, blood clotting disorders); metabolic problems (eg, type 2 diabetes); dysautonomia; paroxysmal orthostatic tachycardia syndrome; myalgic encephalomyelitis/chronic fatigue syndrome; reactivation of the Epstein-Barr virus; the presence of autoantibodies; chronic spontaneous urticaria (hives); and connective tissue diseases.

Whereas long COVID syndrome can affect individuals from various backgrounds, certain populations may be at higher risk such as individuals of Hispanic and Latino heritage, as well as those with low socioeconomic status, although approximately one-third of affected patients have no known risk factors or preexisting conditions.

Many survivors of COVID-19 struggle with multiple symptoms, increased disability, reduced function, and poor quality of life. Whereas vaccination has been the most significant intervention able to decrease the severity of acute SARS-Cov2 infection and curtail deaths, limited data are available related to its modulating effect on long COVID necessitating the need for further investigation. Furthermore, several inflammatory pathways have been proposed for the pathogenesis of long COVID that are the targets for ongoing clinical studies evaluating novel pharmacological agents.

The purpose of the present report is to review the many factors associated with long COVID with a focus on those aspects that have relevance to the allergist-immunologist.

Source: Bellanti JA, Novak P, Faitelson Y, Bernstein JA, Castells MC. The Long Road of Long COVID: Specific Considerations for the Allergist and Immunologist. J Allergy Clin Immunol Pract. 2023 Sep 27:S2213-2198(23)01045-0. doi: 10.1016/j.jaip.2023.09.014. Epub ahead of print. PMID: 37774781. https://www.sciencedirect.com/science/article/abs/pii/S2213219823010450

Potential long-term neurological and gastrointestinal effects of COVID-19: A review of adult cohorts

Abstract:

Background: The respiratory infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved into a multi-organ disorder, with long-term effects known as post-acute sequelae of SARS-CoV-2 infection or long coronavirus disease (COVID).

Aim: To examine the current knowledge and outcomes of long-term neurological and gastrointestinal (GI) symptoms in adult cohorts, including United States minority populations.

Methods: PubMed and Google Scholar were searched using relevant terms, and data from five studies were analyzed, comprising 27383 patients with persistent neurological and GI sequelae.

Results: The main symptoms included anxiety, depression, dysphagia, headache, vomiting, nausea, gastroesophageal reflux, fatigue, and abdominal pain. Patients with comorbidities and metabolic syndromes were at higher risk for long COVID. While most patients were European Americans, there was a need for further study on African Americans.

Conclusion: The underlying causes of these symptoms remain unclear, warranting more investigation into the long-term impact of the SARS-CoV-2 on different populations.

Source: Sherif ZA, Deverapalli M, Challa SR, Martirosyan Z, Whitesell P, Pizuorno AM, Naqvi Z, Tulloch IK, Oskrochi G, Brim H, Ashktorab H. Potential long-term neurological and gastrointestinal effects of COVID-19: A review of adult cohorts. World J Methodol. 2023 Sep 20;13(4):323-336. doi: 10.5662/wjm.v13.i4.323. PMID: 37771866; PMCID: PMC10523249. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10523249/ (Full text)