Efficacy of first dose of covid-19 vaccine versus no vaccination on symptoms of <b>patients</b> with long covid: target trial emulation based on ComPaRe e-cohort

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Objective

To evaluate the effect of covid-19 vaccination on the severity of symptoms in patients with long covid.

Design

Target trial emulation based on ComPaRe e-cohort.

Data source

ComPaRe long covid cohort, a nationwide e-cohort (ie, a cohort where recruitment and follow-up are performed online) of patients with long covid, in France.

Methods

Adult patients (aged ≥18 years) enrolled in the ComPaRe cohort before 1 May 2021 were included in the study if they reported a confirmed or suspected SARS-CoV-2 infection, symptoms persistent for >3 weeks after onset, and at least one symptom attributable to long covid at baseline. Patients who received a first covid-19 vaccine injection were matched with an unvaccinated control group in a 1:1 ratio according to their propensity scores. Number of long covid symptoms, rate of complete remission of long covid, and proportion of patients reporting an unacceptable symptom state at 120 days were recorded.

Results

910 patients were included in the analyses (455 in the vaccinated group and 455 in the control group). By 120 days, vaccination had reduced the number of long covid symptoms (mean 13.0 (standard deviation 9.4) in the vaccinated group v 14.8 (9.8) in the control group; mean difference −1.8, 95% confidence interval −3.0 to −0.5) and doubled the rate of patients in remission (16.6% v 7.5%, hazard ratio 1.93, 95% confidence interval 1.18 to 3.14). Vaccination reduced the effect of long covid on patients' lives (mean score on the impact tool 24.3 (standard deviation 16.7) v 27.6 (16.7); mean difference −3.3, 95% confidence interval −5.7 to −1.0) and the proportion of patients with an unacceptable symptom state (38.9% v 46.4%, risk difference −7.4%, 95% confidence interval −14.5% to −0.3%). In the vaccinated group, two (0.4%) patients reported serious adverse events requiring admission to hospital.

Conclusion

In this study, covid-19 vaccination reduced the severity of symptoms and the effect of long covid on patients' social, professional, and family lives at 120 days in those with persistent symptoms of infection.

Related collections

Most cited references 28

Record: found
Abstract: found
Article: not found

Sensitivity Analysis in Observational Research: Introducing the E-Value.

Peng Ding, Tyler J. VanderWeele (2017)

Sensitivity analysis is useful in assessing how robust an association is to potential unmeasured or uncontrolled confounding. This article introduces a new measure called the "E-value," which is related to the evidence for causality in observational studies that are potentially subject to confounding. The E-value is defined as the minimum strength of association, on the risk ratio scale, that an unmeasured confounder would need to have with both the treatment and the outcome to fully explain away a specific treatment-outcome association, conditional on the measured covariates. A large E-value implies that considerable unmeasured confounding would be needed to explain away an effect estimate. A small E-value implies little unmeasured confounding would be needed to explain away an effect estimate. The authors propose that in all observational studies intended to produce evidence for causality, the E-value be reported or some other sensitivity analysis be used. They suggest calculating the E-value for both the observed association estimate (after adjustments for measured confounders) and the limit of the confidence interval closest to the null. If this were to become standard practice, the ability of the scientific community to assess evidence from observational studies would improve considerably, and ultimately, science would be strengthened.

0 comments Cited 1290 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: found

Is Open Access

Balance diagnostics for comparing the distribution of baseline covariates between treatment groups in propensity-score matched samples

Peter C Austin (2009)

The propensity score is a subject's probability of treatment, conditional on observed baseline covariates. Conditional on the true propensity score, treated and untreated subjects have similar distributions of observed baseline covariates. Propensity-score matching is a popular method of using the propensity score in the medical literature. Using this approach, matched sets of treated and untreated subjects with similar values of the propensity score are formed. Inferences about treatment effect made using propensity-score matching are valid only if, in the matched sample, treated and untreated subjects have similar distributions of measured baseline covariates. In this paper we discuss the following methods for assessing whether the propensity score model has been correctly specified: comparing means and prevalences of baseline characteristics using standardized differences; ratios comparing the variance of continuous covariates between treated and untreated subjects; comparison of higher order moments and interactions; five-number summaries; and graphical methods such as quantile–quantile plots, side-by-side boxplots, and non-parametric density plots for comparing the distribution of baseline covariates between treatment groups. We describe methods to determine the sampling distribution of the standardized difference when the true standardized difference is equal to zero, thereby allowing one to determine the range of standardized differences that are plausible with the propensity score model having been correctly specified. We highlight the limitations of some previously used methods for assessing the adequacy of the specification of the propensity-score model. In particular, methods based on comparing the distribution of the estimated propensity score between treated and untreated subjects are uninformative. Copyright © 2009 John Wiley & Sons, Ltd.

0 comments Cited 1229 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Characterizing long COVID in an international cohort: 7 months of symptoms and their impact

Hannah Davis, Gina Assaf, Lisa McCorkell … (2021)

Background A significant number of patients with COVID-19 experience prolonged symptoms, known as Long COVID. Few systematic studies have investigated this population, particularly in outpatient settings. Hence, relatively little is known about symptom makeup and severity, expected clinical course, impact on daily functioning, and return to baseline health. Methods We conducted an online survey of people with suspected and confirmed COVID-19, distributed via COVID-19 support groups (e.g. Body Politic, Long COVID Support Group, Long Haul COVID Fighters) and social media (e.g. Twitter, Facebook). Data were collected from September 6, 2020 to November 25, 2020. We analyzed responses from 3762 participants with confirmed (diagnostic/antibody positive; 1020) or suspected (diagnostic/antibody negative or untested; 2742) COVID-19, from 56 countries, with illness lasting over 28 days and onset prior to June 2020. We estimated the prevalence of 203 symptoms in 10 organ systems and traced 66 symptoms over seven months. We measured the impact on life, work, and return to baseline health. Findings For the majority of respondents (>91%), the time to recovery exceeded 35 weeks. During their illness, participants experienced an average of 55.9+/- 25.5 (mean+/-STD) symptoms, across an average of 9.1 organ systems. The most frequent symptoms after month 6 were fatigue, post-exertional malaise, and cognitive dysfunction. Symptoms varied in their prevalence over time, and we identified three symptom clusters, each with a characteristic temporal profile. 85.9% of participants (95% CI, 84.8% to 87.0%) experienced relapses, primarily triggered by exercise, physical or mental activity, and stress. 86.7% (85.6% to 92.5%) of unrecovered respondents were experiencing fatigue at the time of survey, compared to 44.7% (38.5% to 50.5%) of recovered respondents. 1700 respondents (45.2%) required a reduced work schedule compared to pre-illness, and an additional 839 (22.3%) were not working at the time of survey due to illness. Cognitive dysfunction or memory issues were common across all age groups (~88%). Except for loss of smell and taste, the prevalence and trajectory of all symptoms were similar between groups with confirmed and suspected COVID-19. Interpretation Patients with Long COVID report prolonged, multisystem involvement and significant disability. By seven months, many patients have not yet recovered (mainly from systemic and neurological/cognitive symptoms), have not returned to previous levels of work, and continue to experience significant symptom burden. Funding All authors contributed to this work in a voluntary capacity. The cost of survey hosting (on Qualtrics) and publication fee was covered by AA's research grant (Wellcome Trust/Gatsby Charity via Sainsbury Wellcome center, UCL).

0 comments Cited 859 times – based on 0 reviews      Review now

Bookmark

All references

Author and article information

Journal

Journal ID (nlm-ta): BMJ Med

Journal ID (iso-abbrev): BMJ Med

Journal ID (hwp): bmjmed

Journal ID (publisher-id): bmjmed

Title: BMJ Medicine

Publisher: BMJ Publishing Group (BMA House, Tavistock Square, London, WC1H 9JR )

ISSN (Electronic): 2754-0413

Publication date Collection: 2023

Publication date (Electronic): 1 February 2023

Publication date PMC-release: 1 February 2023

Volume: 2

Issue: 1

Electronic Location Identifier: e000229

Affiliations

[1 ]Université Paris Cité and Université Sorbonne Paris Nord, Inserm, INRAE, Center for Research in Epidemiology and StatisticS (CRESS) , F-75004 Paris, France

[2 ]departmentCentre d’Epidémiologie Clinique , AP-HP, Hôpital Hôtel Dieu , F-75004 Paris, France

[3 ]Université Paris Cité , Paris, France

[4 ]departmentDepartment of Epidemiology , Columbia University Mailman School of Public Health , New York, New York, USA

Author notes

[Correspondence to ] Dr Viet-Thi Tran, Centre d'Epidémiologie Clinique, Hôpital Hôtel-Dieu, Assistance Publique Hôpitaux de Paris, Paris, 75004, France; thi.tran-viet@ 123456aphp.fr

Author information

Viet-Thi Tran http://orcid.org/0000-0003-1863-6739

Article

Publisher ID: bmjmed-2022-000229

DOI: 10.1136/bmjmed-2022-000229

PMC ID: 9978748

PubMed ID: 36910458

SO-VID: 4b6c2aa9-8ba3-4e27-834f-2521c5aa4e13

License:

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.

History

Date received : 15 April 2022

Date accepted : 25 November 2022

Custom metadata

special-feature unlocked

special-feature press-release

access-type free

Keywords: covid-19

Data availability:

Keywords: covid-19

Comments

Comment on this article

scite_

Cited by 21

See all cited by

Most referenced authors 291

See all reference authors

- Version 1

Efficacy of first dose of covid-19 vaccine versus no vaccination on symptoms of patients with long covid: target trial emulation based on ComPaRe e-cohort

Read this article at

Abstract

Objective

Design

Data source

Methods

Results

Conclusion

Related collections

Novel Coronavirus Disease COVID-19

Most cited references 28

Sensitivity Analysis in Observational Research: Introducing the E-Value.

Balance diagnostics for comparing the distribution of baseline covariates between treatment groups in propensity-score matched samples

Characterizing long COVID in an international cohort: 7 months of symptoms and their impact

Author and article information

Journal

Affiliations

Author notes

Author information

Article

History

Categories

Custom metadata

Comments

Comment on this article

Similar content 119

Cited by 21

Most referenced authors 291