Risque de poussée après le vaccin COVID-19 chez les patients atteints de sclérose en plaques en France : étude nationale de type « self-controlled case series »

Introduction Les patients ayant une sclérose en plaques (SEP) ont parfois des réticences concernant la vaccination, notamment en raison d'idées fausses qui ont été largement diffusées concernant la vaccination de l'hépatite B. Objectifs Étudier l'association entre la vaccination COVID-19 et le risque de survenue de poussées de SEP. Méthodes Les données du Système national des données de santé (SNDS, 68 millions de Français couverts) ont été utilisées pour identifier tous les patients présentant une SEP, et un algorithme a permis d'identifier toutes les poussées ayant nécessité un traitement par corticoïdes à fortes doses. Une méthode de type « self-controlled case series » a été utilisée pour comparer les périodes exposées à la vaccination à celles non exposées, globalement et dans des sous-groupes d'intérêt. Résultats Au total, 124 545 patients SEP ont été identifiés, dont plus de 80 % ont reçu au moins une dose vaccinale. Les patients ne présentaient aucune majoration du risque de poussée, que la période d'analyse porte sur les 6 ou les 12 semaines après la vaccination. Ces données étaient les mêmes après la deuxième dose vaccinale. Il existait même une légère diminution du risque de poussée pendant quelques semaines, dans les suites de chaque vaccination. Discussion Cette étude de grande ampleur, portant sur la France entière, et utilisant une méthodologie adaptée autocontrôlée (chaque patient étant son propre témoin), ne montre pas d'augmentation du risque de poussée de SEP après une vaccination contre le COVID, là où de nombreuses séries de cas de petit effectif avaient montré l'existence de poussées inflammatoires dans les suites de la vaccination. Conclusion Ces données très rassurantes permettent de poursuivre l'incitation vaccinale chez nos patients SEP, en particulier chez ceux ayant des facteurs de risque d'infection grave (âge, handicap, obésité, traitement par anti-CD20…).

Impact of ICU transfers on the mortality rate of patients with COVID-19: insights from comprehensive national database in France.

BACKGROUND: The first wave of the COVID-19 pandemic confronted healthcare systems around the world with unprecedented organizational challenges, particularly regarding the availability of intensive care unit (ICU) beds. One strategy implemented in France to alleviate healthcare pressure during the first COVID-19 wave was inter-hospital transfers of selected ICU patients from overwhelmed areas towards less saturated ones. At the time, the impact of this transfer strategy on patient mortality was unknown. We aimed to compare in-hospital mortality rates among ICU patients with COVID-19 who were transferred to another healthcare facility and those who remained in the hospital where they were initially admitted to. METHOD: A prospective observational study was performed from 1 March to 21 June 2020. Data regarding hospitalized patients with COVID-19 were collected from the Ministry of Health-affiliated national SI-VIC registry. The primary endpoint was in-hospital mortality. RESULTS: In total, 93,351 hospital admissions of COVID-19 patients were registered, of which 18,348 (19.6%) were ICU admissions. Transferred patients (n = 2228) had a lower mortality rate than their non-transferred counterparts (n = 15,303), and the risk decreased with increasing transfer distance (odds ratio (OR) 0.7, 95% CI: 0.6-0.9, p = 0.001 for transfers between 10 and 50 km, and OR 0.3, 95% CI: 0.2-0.4, p < 0.0001 for transfer distance > 200 km). Mortality decreased overall over the 3-month study period. CONCLUSIONS: Our study shows that the mortality rates were lower for patients with severe COVID-19 who were transferred between ICUs across regions, or internationally, during the first pandemic wave in France. However, the global mortality rate declined overall during the study. Transferring selected patients with COVID-19 from overwhelmed regions to areas with greater capacity may have improved patient access to ICU care, without compounding the short-term mortality risk of transferred patients.

TRANSCOV cohort protocol: an epidemiological study assessing the impact of critically ill COVID-19 patients long distance transfers between intensive care units.

INTRODUCTION: During spring 2020, four regions of France faced a surge of severe COVID-19 patients which threatened to overflow local intensive care units (ICU) capacities. As an emergency response, between 13 March 2020 and 10 April 2020, an estimated 661 patients were transferred from overcrowded ICUs to eight other French regions and four neighbouring countries. The intensity, geographical spread and the diversity of vectors used are unprecedented. The study aims at assessing the impact of these inter-ICU transfers on the short-term and medium-term physical and psychological outcomes in this population of severe COVID-19 patients. METHODS AND ANALYSIS: The TRANSCOV cohort is a multicentre observational retrospective study. All transferred patients between ICUs outside the origin region will be invited to take part. For each transfer, up to four control patients will be selected among those admitted in the same ICU during the same period (±4 days of transfer date). Clinical data will be extracted from medical records and will include haemodynamic and respiratory parameters, as well as clinical severity scores before, during and after transfer. Data linkage with medicoadministrative data will enrich the clinical database and allow follow-up up to 1 year after initial admission. ETHICS AND DISSEMINATION: The study has been approved by the French Ethics and Scientific Committee on the 16 July 2020 (file no. 2046524). The results will be disseminated via publication of scientific articles and communications in national and international conferences. TRIAL REGISTRATION NUMBER: 20 CO 015 CZ.