The long COVID evidence gap in England

Introduction:

The term long COVID, also known as post-COVID-19 condition, was coined in spring, 2020, by individuals with ongoing symptoms following COVID-19 in response to unsatisfactory recognition of this emerging syndrome by health-care practitioners.

In September to November, 2020, clinical codes for persistent post-COVID-19 condition and related referrals were introduced and became available for use by health-care practitioners to record details of clinical encounters in electronic health records (EHRs) in England. EHRs, which cover a large proportion of individuals living in England, are increasingly used to help understand the epidemiology of disease alongside the effectiveness and safety of interventions.
Many factors influence the completeness of information in EHRs, including help-seeking behaviour of patients and the discretion and data-recording behaviour of practitioners. Longitudinal population-based studies often include participant self-reports of illness; hence, these studies might be subject to reporting and participation biases. Comparing reported illness in studies to recorded illness in the EHRs of the same individuals might be helpful in understanding the epidemiology and clinical recognition of emerging conditions such as long COVID.
Source: Knuppel A, Boyd A, Macleod J, Chaturvedi N, Williams DM. The long COVID evidence gap in England. Lancet. 2024 May 6:S0140-6736(24)00744-X. doi: 10.1016/S0140-6736(24)00744-X. Epub ahead of print. PMID: 38729195. https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(24)00744-X/fulltext (Full text)

Prevalence and Factors Associated with Long COVID Symptoms among U.S. Adults, 2022

Abstract:

Long COVID and its symptoms have not been examined in different subpopulations of U.S. adults. Using the 2022 BRFSS (n = 445,132), we assessed long COVID and each symptom by sociodemographic characteristics and health-related variables. Multivariable logistic regression was conducted to examine factors associated with long COVID and the individual symptoms. Prevalence differences were conducted to examine differences in long COVID by vaccination status.

Overall, more than one in five adults who ever had COVID-19 reported symptoms consistent with long COVID (21.8%). The most common symptom was tiredness or fatigue (26.2%), followed by difficulty breathing or shortness of breath (18.9%), and loss of taste or smell (17.0%). Long COVID was more common among adults under 65 years, women, American Indian or Alaska Native or other/multi race group, smokers, and people with a disability, depression, overweight or obesity compared to their respective counterparts.

The prevalence of long COVID was higher among unvaccinated adults (25.6%) than vaccinated adults (21.6%) overall, and for 20 of 32 subgroups assessed. These findings underscore the benefits of vaccination, the importance of early treatment, and the need to better inform health care resource allocation and support services for those experiencing long COVID.

Source: Nguyen KH, Bao Y, Mortazavi J, Allen JD, Chocano-Bedoya PO, Corlin L. Prevalence and Factors Associated with Long COVID Symptoms among U.S. Adults, 2022. Vaccines (Basel). 2024 Jan 18;12(1):99. doi: 10.3390/vaccines12010099. PMID: 38250912; PMCID: PMC10820629. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10820629/ (Full text)

Risk factors for experiencing Long-COVID symptoms: Insights from two nationally representative surveys

Abstract:

Background Long COVID (LC) is a complex and multisystemic condition marked by a diverse range of symptoms, yet its associated risk factors remain poorly defined.

Methods Leveraging data from the 2022 Behavioral Risk Factor Surveillance System (BRFSS) and National Health Interview Survey (NHIS), both representative of the United States population, this study aimed to identify demographic characteristics associated with LC. The sample was restricted to individuals aged 18 years and older who reported a positive COVID-19 test or doctor’s diagnosis. We performed a descriptive analysis comparing characteristics between participants with and without LC. Furthermore, we developed multivariate logistic regression models on demographic covariates that would have been valid at the time of the COVID-19 infection.

Results Among the 124,313 individuals in BRFSS and 10,131 in the NHIS reporting either a positive test or doctor’s diagnosis for COVID-19 (Table), 26,783 (21.5%) in BRFSS and 1,797 (17.1%) in NHIS reported LC. In the multivariate logistic regression model, we found middle age, female gender, Hispanic ethnicity, lack of a college degree, and residence in non-metropolitan areas associated with higher risk of LC. Notably, the initial severity of acute COVID-19 was strongly associated with LC risk. In contrast, significantly lower ORs were reported for Non-Hispanic Asian and Black Americans compared to Non-Hispanic White.

Conclusions In the United States, there is marked variation in the risk of LC by demographic factors and initial infection severity. Further research is needed to understand the underlying cause of these observations.

Source: Yixuan WuMitsuaki SawanoYilun WuRishi M. ShahPamela BishopAkiko IwasakiHarlan M. Krumholz. Risk factors for experiencing Long-COVID symptoms: Insights from two nationally representative surveys.

Prevalence of covid-19 and long covid in collegiate student athletes from spring 2020 to fall 2021: a retrospective survey

Abstract:

Background: Symptomatic COVID-19 and Long COVID, also referred to as post-acute sequelae of SARS-CoV-2 (PASC) or post-COVID conditions, have been widely reported in young, healthy people, but their prevalence has not yet been determined in student athletes. We sought to estimate the prevalence of reported COVID-19, symptomatic COVID-19, and Long COVID in college athletes in the United States attending 18 schools from spring 2020 to fall 2021.

Methods: We developed an online survey to measure the prevalence of student athletes who tested positive for COVID-19, developed Long COVID, and did not return to their sport during the relevant time period. We surveyed a convenience sample of 18 collegiate school administrators, representing about 7,000 student athletes. Of those schools surveyed, 16 responded regarding the spring 2020 semester, and 18 responded regarding the full academic year of fall 2020 to spring 2021 (both semesters).

Results: According to the survey responses, there were 9.8% of student athletes who tested positive for COVID-19 in spring 2020 and 25.4% who tested positive in the academic year of fall 2020 to spring 2021. About 4% of student athletes who tested positive from spring 2020 to spring 2021 developed Long COVID, defined as new, recurring, or ongoing physical or mental health consequences occurring 4 or more weeks after SARS-CoV-2 infection.

Conclusions: This study highlights that Long COVID occurs among young, healthy athletes and is a real consequence of COVID-19. Understanding the prevalence of Long COVID in this population requires longer follow-up and further study.

Source: Massey D, Saydah S, Adamson B, Lincoln A, Aukerman DF, Berke EM, Sikka R, Krumholz HM. Prevalence of covid-19 and long covid in collegiate student athletes from spring 2020 to fall 2021: a retrospective survey. BMC Infect Dis. 2023 Dec 13;23(1):876. doi: 10.1186/s12879-023-08801-z. PMID: 38093182; PMCID: PMC10717379. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10717379/ (Full text)

A National Evaluation of Outcomes in Long COVID Services using Digital PROM Data from the ELAROS Platform

Summary:

Key findings of this service evaluation study:
• Patient characteristics: A sample of 5,318 patients from 14 participating NHS LC sites were analysed. The sample had a female:male ratio of 2.1:1. The average age was 48.4 yrs, with 87% (of those whose ethnicity was recorded) of white ethnicity and 9% of Black or Asian ethnicity.
• Comorbidities: This sample of patients had a low prevalence of co-morbidities (7%) with a clear onset of new LC symptoms after their COVID-19 infection supporting the onset of a new condition in this cohort of previously healthy individuals.
• Duration of LC: The average duration of LC in this sample was 384 days (>12 months) at first assessment in an LC site, with symptoms still ongoing at presentation, with more than 90% of the sample being non-hospitalised patients.
• Digital platform: A total of 17,471 PROMs (C19-YRS and EQ-5D-5L) were completed by this sample of patients with at least 1,532 participants completing multiple assessments on the same PROM on the digital PROM platform. The completion of PROMs around the 3-month mark was low for both measures (11.7% for C19-YRS and 14.6% for EQ-5D-5L). The ones who completed PROMs both around the 3-month mark and the 6-month mark were 4.3% for C19-YRS and 5% for EQ-5D-5L. This limits the generalisability of the findings in this evaluation to all the LC population, but the findings remain valid for this cohort of individuals.
• New-onset disability: 3,395 patients who completed at least one C19-YRS questionnaire at first assessment showed significant new-onset symptom burden, functional disability, and deterioration of overall health since the COVID-19 infection.
• Comparison between LC and other chronic conditions: The cross-sectional EQ-5D-5L Index value of 3,438 patients suggests the burden and disability in LC are worse than that reported in the literature for Diabetes Mellitus, COPD, Heart Failure, and Multiple Sclerosis.
• 3-month follow-up: Among those who completed an initial C19-YRS assessment and another at 3 months, there was a statistically significant improvement in symptom burden, functional disability and overall health. Patients at 3 months however still had significant LC symptom
burden and disability compared to their pre-COVID-19 health status, i.e., their condition had improved, but they were far off from a complete recovery. Among those who completed EQ-5D- National Evaluation of Long COVID Service Outcomes using ELAROS Data (09 Oct 23) Page 3 of 31
5L, at first assessment and at 3 months, their EQ-5D-5L Index score did not show any statistically significant improvement, but the EQ-5D-5L VAS showed a statistically significant improvement.
• 6-month follow-up: Among those who completed measures at the first assessment, 3 months, and 6 months, C19-YRS and EQ-5D-5L VAS showed statistically significant improvement whereas EQ-5D-5L Index Value showed statistically significant deterioration. Patients at 6 months still had
significant LC symptom burden and disability compared to their pre-COVID-19 health status, i.e., their condition had improved but had not fully recovered. The follow-up changes in scores support the efficacy of interventions provided by LC services and suggest that continued specialist input is needed to manage these patients with persistent symptoms.
• C19-YRS (condition-specific measure) vs EQ-5D-5L (generic measure): The 3-month month follow-up changes in scores and responsiveness of PROMs highlight that C19-YRS is a more sensitive measure than EQ-5D-5L in this cohort of individuals with LC. This is in keeping with the literature recommending the use of condition-specific measures in addition to EQ-5D-5L.
• Vocational problems: 62% of this sample had their work role affected with them having to either be on sick leave, reduce hours, change roles, or quit roles. Only 21% were able to maintain their previous roles held prior to their COVID-19 infection. This is suggestive of considerable productivity loss and financial implications to the country.
• Fluctuating condition: In patients who completed multiple assessments, it was evident that LC is a fluctuant condition with no necessary linear trend of improvement or deterioration between the domains of symptom burden, functional disability, and overall health. This highlights the need to understand the triggers for the condition and invest in self-management and ongoing support from community healthcare services.
• Long-Term Condition: In most patients in this sample, LC has evidently become a Long-Term Condition (LTC) with fluctuations in their condition causing disability and significant deterioration of their overall health status seen even after 18 months of LC with no complete resolution or full recovery. There needs to be a national investment in managing this new LTC along with other LTCs.

Source: Dr Manoj Sivan, et al.  A National Evaluation of Outcomes in Long COVID Services using Digital PROM Data from the ELAROS Platform. National Evaluation of Long COVID Service Outcomes using ELAROS Data (09 Oct 23) https://locomotion.leeds.ac.uk/wp-content/uploads/sites/74/2023/10/National-Evaluation-of-LC-Service-Outcomes-using-ELAROS-Data-09-10-23.pdf (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

Long COVID and Significant Activity Limitation Among Adults, by Age — United States, June 1–13, 2022, to June 7–19, 2023

Summary:

What is already known about this topic? Long COVID includes a wide range of ongoing symptoms that can last for weeks, months, or years following SARS-CoV-2 infection.

What is added by this report? Prevalence of long COVID among noninstitutionalized U.S. adults aged ≥18 years decreased from 7.5% (95% CI = 7.1–7.9) during June 1–13, 2022 to 6.0% (95% CI = 5.7–6.3) during June 7–19, 2023 and from 18.9% (95% CI = 17.9–19.8) to 11.0% (95% CI = 10.4–11.6) among adults reporting previous COVID-19. After an initial decline, prevalence remained unchanged beginning January 4–16, 2023. Approximately one quarter of adults with long COVID report significant activity limitations.

What are the implications for public health practice? COVID-19 prevention efforts, including staying up to date with recommended COVID-19 vaccination and planning for long COVID symptom management and health care service needs, remain important.

Abstract:

Long COVID is a condition encompassing a wide range of health problems that emerge, persist, or return following COVID-19. CDC analyzed national repeat cross-sectional Household Pulse Survey data to estimate the prevalence of long COVID and significant related activity limitation among U.S. adults aged ≥18 years by age group.

Data from surveys completed between June 1–13, 2022, and June 7–19, 2023, indicated that long COVID prevalence decreased from 7.5% (95% CI = 7.1–7.9) to 6.0% (95% CI = 5.7–6.3) among the overall U.S. adult population, irrespective of history of previous COVID-19, and from 18.9% (95% CI = 17.9–19.8) to 11.0% (95% CI = 10.4–11.6) among U.S. adults reporting previous COVID-19. Among both groups, prevalence decreased from June 1–13, 2022, through January 4–16, 2023, before stabilizing.

When stratified by age, only adults aged <60 years experienced significant rates of decline (p<0.01). Among adults reporting previous COVID-19, prevalence decreased among those aged 30–79 years through fall or winter and then stabilized.

During June 7–19, 2023, 26.4% (95% CI = 24.0–28.9) of adults with long COVID reported significant activity limitation, the prevalence of which did not change over time.

These findings help guide the ongoing COVID-19 prevention efforts and planning for long COVID symptom management and future health care service needs.

Source:  Ford ND, Slaughter D, Edwards D, et al. Long COVID and Significant Activity Limitation Among Adults, by Age — United States, June 1–13, 2022, to June 7–19, 2023. MMWR Morb Mortal Wkly Rep 2023;72:866–870. DOI: http://dx.doi.org/10.15585/mmwr.mm7232a3 (Full text)

Mast cell activation may contribute to adverse health transitions in COVID-19 patients with frailty

Abstract:

A prominent aspect of the post-coronavirus disease-2019 (post-COVID-19) era is long-COVID. Therefore, precise patient classification and exploration of the corresponding factors affecting long-COVID are crucial for tailored treatment strategies. Frailty is a common age-related clinical syndrome characterized by deteriorated physiological functions of multiple organ systems, which increases susceptibility to stressors.

Herein, we performed an inclusion and exclusion analysis (definite COVID-19 infection diagnosis, clear underlying disease information, ≥60 years old, and repeated sampling of clinical cases) of 10,613 blood samples and identified frailty cases for further investigation. RNA-Seq data were used for differential gene expression and functional and pathway analyses.

The results revealed that patients with frailty were more prone to poor health conversions and more sequelae, and the blood transcriptome had obvious disturbances in pathways associated with immune regulation, metabolism, and stress response. These adverse health transitions were significantly associated with mast cell activation. Additionally, NCAPG, MCM10, and CDC25C were identified as hub genes in the peripheral blood differential gene cluster, which could be used as diagnostic markers of poor health conversion.

Our results indicate that healthcare measures should be prioritized to mitigate adverse health outcomes in this vulnerable patient group, COVID-19 patients with frailty, in post-COVID era.

Source: Xiangqi Li, Chaobao Zhang & Zhijun Bao (2023) Mast cell activation may contribute to adverse health transitions in COVID-19 patients with frailty, Emerging Microbes & Infections, 12:2, DOI: 10.1080/22221751.2023.2251589 https://www.tandfonline.com/doi/pdf/10.1080/22221751.2023.2251589 (Full text)

Acute and post-acute sequelae of SARS-CoV-2 infection: a review of risk factors and social determinants

Abstract:

SARS-CoV-2 infection leading to Coronavirus Disease 2019 (COVID-19) has caused more than 762 million infections worldwide, with 10-30% of patients suffering from post-acute sequelae of SARS-CoV-2 infections (PASC). Initially thought to primarily affect the respiratory system, it is now known that SARS-CoV-2 infection and PASC can cause dysfunction in multiple organs, both during the acute and chronic stages of infection.

There are also multiple risk factors that may predispose patients to worse outcomes from acute SARS-CoV-2 infection and contribute to PASC, including genetics, sex differences, age, reactivation of chronic viruses such as Epstein Barr Virus (EBV), gut microbiome dysbiosis, and behavioral and lifestyle factors, including patients’ diet, alcohol use, smoking, exercise, and sleep patterns.

In addition, there are important social determinants of health, such as race and ethnicity, barriers to health equity, differential cultural perspectives and biases that influence patients’ access to health services and disease outcomes from acute COVID-19 and PASC.

Here, we review risk factors in acute SARS-CoV-2 infection and PASC and highlight social determinants of health and their impact on patients affected with acute and chronic sequelae of COVID-19.

Source: Wang C, Ramasamy A, Verduzco-Gutierrez M, Brode WM, Melamed E. Acute and post-acute sequelae of SARS-CoV-2 infection: a review of risk factors and social determinants. Virol J. 2023 Jun 16;20(1):124. doi: 10.1186/s12985-023-02061-8. PMID: 37328773; PMCID: PMC10276420. https://virologyj.biomedcentral.com/articles/10.1186/s12985-023-02061-8 (Full text)

Use of latent class analysis and patient reported outcome measures to identify distinct long COVID phenotypes: A longitudinal cohort study

Abstract:

Objectives: We sought to 1) identify long COVID phenotypes based on patient reported outcome measures (PROMs) and 2) determine whether the phenotypes were associated with quality of life (QoL) and/or lung function.

Methods: This was a longitudinal cohort study of hospitalized and non-hospitalized patients from March 2020 to January 2022 that was conducted across 4 Post-COVID Recovery Clinics in British Columbia, Canada. Latent class analysis was used to identify long COVID phenotypes using baseline PROMs (fatigue, dyspnea, cough, anxiety, depression, and post-traumatic stress disorder). We then explored the association between the phenotypes and QoL (using the EuroQoL 5 dimensions visual analogue scale [EQ5D VAS]) and lung function (using the diffusing capacity of the lung for carbon monoxide [DLCO]).

Results: There were 1,344 patients enrolled in the study (mean age 51 ±15 years; 780 [58%] were females; 769 (57%) were of a non-White race). Three distinct long COVID phenotypes were identified: Class 1) fatigue and dyspnea, Class 2) anxiety and depression, and Class 3) fatigue, dyspnea, anxiety, and depression. Class 3 had a significantly lower EQ5D VAS at 3 (50±19) and 6 months (54 ± 22) compared to Classes 1 and 2 (p<0.001). The EQ5D VAS significantly improved between 3 and 6 months for Class 1 (median difference of 6.0 [95% CI, 4.0 to 8.0]) and Class 3 (median difference of 5.0 [95% CI, 0 to 8.5]). There were no differences in DLCO between the classes.

Conclusions: There were 3 distinct long COVID phenotypes with different outcomes in QoL between 3 and 6 months after symptom onset. These phenotypes suggest that long COVID is a heterogeneous condition with distinct subpopulations who may have different outcomes and warrant tailored therapeutic approaches.

Source: Wong AW, Tran KC, Binka M, Janjua NZ, Sbihi H, Russell JA, Carlsten C, Levin A, Ryerson CJ. Use of latent class analysis and patient reported outcome measures to identify distinct long COVID phenotypes: A longitudinal cohort study. PLoS One. 2023 Jun 2;18(6):e0286588. doi: 10.1371/journal.pone.0286588. PMID: 37267379; PMCID: PMC10237387. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10237387/ (Full text)