Thrombosis Center University Hospital Careggi, Florence, Italy.
Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy.
Blood Transfus. 2022 Sep;20(5):433-436. doi: 10.2450/2022.0271-21. Epub 2022 Feb 28.
Since the outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, administration of the currently available vaccines has mostly been recommended for subjects at high risk, including elderly populations on long-term oral anticoagulation therapy (OAT) with warfarin. However, there is no clear evidence of the stability of the International Normalised Ratio (INR) after vaccine administration in those subjects on long-term OAT. The present study aimed to investigate the effects of COVID-19 vaccination on anticoagulation levels in patients on long-term OAT.
INR values of patients on long-term OAT who had undergone anti-SARS-CoV-2 vaccination from January to June 2021 were monitored for a total of 90 days follow-up after the first vaccination dose. These were then compared with INR values before vaccination. The second dose, when required, was administered during follow-up. Inclusion criterion was stable long-term INR for at least 6 months before vaccination. Exclusion criteria were recent surgery, intercurrent diseases, or treatment with medication that could compromise findings in the 3 months before vaccination and during follow-up.
No differences were observed in the anticoagulation levels before and after COVID-19 vaccination in any of the patients studied: mean INR values were 2.39 (range 2.20-2.63) before vaccination and 2.40 (range 2.16-2.76) after vaccination (p=0.5). There was no difference in anticoagulation levels in relation to age, sex, indication for OAT, or type of vaccine (p>0.5). No bleeding or thrombotic complications were documented during follow-up.
These are the first data to be reported on anticoagulation levels in patients on stable OAT after COVID-19 vaccination. No influence on the quality of OAT was detected after the vaccination; no bleeding or thrombotic complications were recorded in the follow-up. No difference between the four available COVID vaccines was found. Dose adjustment was only required in a few cases, thus confirming the stability of anticoagulation levels.
自严重急性呼吸综合征冠状病毒 2 (SARS-CoV-2) 大流行爆发以来，目前可用的疫苗主要推荐给高危人群，包括长期接受华法林口服抗凝治疗 (OAT) 的老年人群。然而，目前尚不清楚长期接受 OAT 的人群在接种疫苗后国际标准化比值 (INR) 是否稳定。本研究旨在调查 COVID-19 疫苗接种对长期接受 OAT 的患者抗凝水平的影响。
从 2021 年 1 月至 6 月，对接受过抗 SARS-CoV-2 疫苗接种的长期接受 OAT 的患者的 INR 值进行监测，共随访 90 天，直至第一剂疫苗接种后。然后将这些与接种疫苗前的 INR 值进行比较。如有需要，在随访期间接种第二剂疫苗。纳入标准是在接种疫苗前至少 6 个月稳定的长期 INR。排除标准是最近的手术、并发疾病或在接种疫苗前和随访期间使用可能影响结果的药物治疗。
在所研究的患者中，COVID-19 疫苗接种前后的抗凝水平没有差异：接种疫苗前的平均 INR 值为 2.39（范围 2.20-2.63），接种疫苗后为 2.40（范围 2.16-2.76）（p=0.5）。年龄、性别、OAT 适应证或疫苗类型与抗凝水平无差异（p>0.5）。在随访期间未记录到出血或血栓形成并发症。
这是首次报道稳定接受 OAT 的患者在 COVID-19 疫苗接种后的抗凝水平。接种疫苗后未发现对 OAT 质量的影响；在随访中未记录到出血或血栓形成并发症。在四种可用的 COVID 疫苗之间未发现差异。仅在少数情况下需要调整剂量，从而证实了抗凝水平的稳定性。
