Abstract:
Vitamin K antagonists (VKA) is the primary anticoagulant in most settings of Sub-Saharan Africa. Understanding the quality of anticoagulation services in the continent is vital in optimising the intended benefits. This study assessed the quality of anticoagulation and associated factors among VKA-treated patients in nine SSA countries. We conducted a retrospective cohort study of randomly selected patients on anticoagulation from 20 clinics in Botswana, the Democratic Republic of Congo, Ethiopia, Gambia, Ghana, Mozambique, Nigeria, Tanzania, and South Africa. Eligible participants were those on VKAs for at least three months and with at least four international normalised ratios (INR) results in 2019-2021. We report the proportion of INR values in the therapeutic range, time-in-therapeutic range (TTR) using the Rosendaal method, and the proportion of patients with TTR ≥ 65% (optimal anticoagulation). The mean age was 51.1(16.1) years, and 64.2% were women. The most common indications for VKA included venous thromboembolism (29.6%), prosthetic valves (26.7%) and atrial fibrillation/flutter (30.1%). We analysed 6743 INR tests from 1011 participants, and of these, 48.5% were sub-therapeutic, 34.1% therapeutic, and 17.4% were supratherapeutic relative to disease-specific reference ranges. TTR was calculated for 660 patients using 4927 INR measurements. The median (interquartile range [IQR]) TTR was 35.8(15.9,57.2) %. Optimal anticoagulation control was evident in 19.2% of participants, varying from 2.7% in Tanzania to 23.1% in Ethiopia. The proportion of patients with TTR ≥ 65% was 15,4% for prosthetic heart valves, 21.1% for venous thromboembolism and 23.7% for atrial fibrillation or flutter. Countries with universal health coverage had higher odds of optimal anticoagulation control (adjusted odds ratio (aOR) 1.79, 95% confidence interval [CI], 1.15- 2.81, p = 0.01). Patients on VKAs for different therapeutic indications in SSA had suboptimal TTR. Universal health coverage increased the odds of achieving TTR by 79%. The evidence calls for more intensive warfarin management strategies in SSA, including providing VKA services without out-of-pocket payments.
摘要:
维生素K拮抗剂(VKA)是撒哈拉以南非洲大多数地区的主要抗凝剂。了解非洲大陆抗凝服务的质量对于优化预期的益处至关重要。这项研究评估了9个SSA国家接受VKA治疗的患者的抗凝质量和相关因素。我们进行了一项回顾性队列研究,对来自博茨瓦纳20个诊所的随机选择的抗凝患者,刚果民主共和国,埃塞俄比亚,冈比亚,加纳,莫桑比克,尼日利亚,坦桑尼亚,和南非。符合条件的参与者是那些在VKAs上至少三个月并且在2019-2021年至少有四个国际标准化比率(INR)结果的参与者。我们报告了INR值在治疗范围内的比例,使用Rosendaal方法的治疗时间范围(TTR),以及TTR≥65%(最佳抗凝)的患者比例。平均年龄为51.1(16.1)岁,64.2%为女性。VKA最常见的适应症包括静脉血栓栓塞(29.6%),人工瓣膜(26.7%)和心房颤动/扑动(30.1%)。我们分析了1011名参与者的6743项INR测试,其中,48.5%为亚治疗,34.1%治疗,相对于疾病特异性参考范围,17.4%是超治疗性的。使用4927INR测量值计算660名患者的TTR。中位数(四分位数间距[IQR])TTR为35.8(15.9,57.2)%。最佳抗凝控制在19.2%的参与者中明显,从坦桑尼亚的2.7%到埃塞俄比亚的23.1%不等。TTR≥65%的患者比例为15,4%用于人工心脏瓣膜,21.1%用于静脉血栓栓塞,23.7%用于心房颤动或扑动。全民健康覆盖的国家获得最佳抗凝控制的几率较高(调整比值比(aOR)1.79,95%置信区间[CI],1.15-2.81,p=0.01)。在SSA中接受不同治疗适应症的VKAs患者的TTR不理想。全民健康覆盖使实现TTR的几率增加了79%。证据要求在SSA中采用更密集的华法林管理策略,包括提供VKA服务而无需自付费用。