ABSTRACT
Background: Concerns emerged for the management of intramuscular (IM) injections for COVID-19 vaccines in patients with therapeutic anticoagulation. Aim(s): The aim of the study was to evaluate the risk of bleeding events following IM vaccination in patients under therapeutic anticoagulation Methods: We first performed a French multicentre prospective study including patient treated by anticoagulant therapy for venous thromboembolism between May 2021 and September 2021. Consecutive patients were asked to report bleeding events at the site of COVID-19 vaccine injection during follow-up. We next performed a request in the French national pharmacovigilance database to identify cases of bleeding events at the site of injections following COVID-19 vaccine in patients under therapeutic anticoagulation between December, 27th, 2020 and June, 30th, 2021. Result(s): Between May and September 2021, a total of 348 patients with anticoagulant therapy received 561 IM injections of COVD-19 vaccines. Median age of patients was 68.4 years and 65.2% were males. Almost all patients were treated with direct oral anticoagulant (DOAC 96.6%), 11 (3.2%) patients with vitamin K antagonist and one (0.2%) with tinzaparin. Among them, 17.9% had pressure at the injection site after the injection and 4.2% had anticoagulant dose skipping before vaccination. After IM injections, a total of 3 (0.6%) bleeding events were observed, 2 (0.4%) minor and one (0.2%) clinically relevant non-major bleeding. We next observed in the French national pharmacovigilance database a total of 13 bleeding events (all minor bleeding) at the site of injection in patients on therapeutic anticoagulation between December, 27th, 2020 and June, 30th, 2021. In France, 69,089,410 doses of COVID-19 vaccine were administered during this period. These bleeding events correspond to a spontaneous notification rate of 0.19 cases (95% CI 0.09-0.29) reported per million of doses administered. Conclusion(s): IM vaccination appears safe in patients under therapeutic anticoagulation in particular with DOAC, and may not require skipping doses.
ABSTRACT
Preliminary data and clinical experience have suggested an increased risk of abnormal uterine bleeding (AUB) in women of reproductive age treated with anticoagulants, but solid data are lacking. The TEAM-VTE study was an international multicenter prospective cohort study in women aged 18 to 50 years diagnosed with acute venous thromboembolism (VTE). Menstrual blood loss was measured by pictorial blood loss assessment charts at baseline for the last menstrual cycle before VTE diagnosis and prospectively for each cycle during 3 to 6 months of follow-up. AUB was defined as an increased score on the pictorial blood loss assessment chart (>100 or >150) or self-reported AUB. AUB-related quality of life (QoL) was assessed at baseline and the end of follow-up using the Menstrual Bleeding Questionnaire. The study was terminated early because of slow recruitment attributable to the COVID-19 pandemic. Of the 98 women, 65 (66%) met at least one of the 3 definitions of AUB during follow-up (95% confidence interval [CI], 57%-75%). AUB occurred in 60% of women (36 of 60) without AUB before VTE diagnosis (new-onset AUB; 95% CI, 47%-71%). Overall, QoL decreased over time, with a mean Menstrual Bleeding Questionnaire score increase of 5.1 points (95% CI, 2.2-7.9), but this decrease in QoL was observed only among women with new-onset AUB. To conclude, 2 of every 3 women who start anticoagulation for acute VTE experience AUB, with a considerable negative impact on QoL. These findings should be a call to action to increase awareness and provide evidence-based strategies to prevent and treat AUB in this setting. This was an academic study registered at www.clinicaltrials.gov as #NCT04748393; no funding was received.