From the Department of Pharmacy and Therapeutics, School of Pharmacy (I.H.) and Department of Health Policy and Management, Graduate School of Public Health (Y.Z.), University of Pittsburgh, PA; and Heart and Valvular Institute, University of Pittsburgh Medical Centre, PA (S.S.).
Stroke. 2017 Aug;48(8):2289-2291. doi: 10.1161/STROKEAHA.117.017683. Epub 2017 Jun 27.
Underuse of oral anticoagulation in stroke prevention in atrial fibrillation is common; however, it remains unknown how it varies geographically. The objective of this study was to evaluate geographic variation in oral anticoagulation use and in the initiation of new oral anticoagulants (NOACs).
Using 2013 to 2014 claims data from a 5% random sample of Medicare beneficiaries, we identified patients newly diagnosed with atrial fibrillation who initiated NOACs (n=8659), warfarin (n=11 771) or no oral anticoagulation therapy (n=18 226) in 2013 to 2014. Each patient was assigned to 1 of the 306 Dartmouth hospital-referral regions based on his/her zip code. We constructed logistic regressions to calculate the mean adjusted probability of initiating oral anticoagulation and the mean adjusted probability of initiating an NOAC among patients on oral anticoagulation in each hospital-referral region, after adjustment for demographic, clinical, and provider characteristics and type of insurance. Finally, we computed the correlation between 2 probabilities.
Higher in the Midwest (0.54) and Northeast (0.54) and lowest in the South (0.47), the mean adjusted probability of initiating oral anticoagulation was 0.51, ranging from 0.32 to 0.72. The mean adjusted probability of being prescribed an NOAC among those on oral anticoagulation was 0.42 and was highest in the South (0.50) and lowest in the Midwest (0.36) and Northeast (0.39). In areas with the lower use of oral anticoagulation, patients on any oral anticoagulation therapy had a higher likelihood of being prescribed an NOAC (correlation coefficient, -0.16; =0.006).
Large geographic variation exists in oral anticoagulation use in atrial fibrillation. The use of oral anticoagulation is lower in the South, where the rates of stroke are unusually high. In the future, it will be important to analyze whether the high rates of stroke in the South can be partially attributed to the underuse of oral anticoagulation in this region.
在预防房颤卒中时，抗凝药物的使用不足较为常见；然而，其地域差异仍不清楚。本研究旨在评估口服抗凝药物的使用情况以及新型口服抗凝剂（NOAC）的起始使用情况在地域上的差异。
利用 2013 年至 2014 年 Medicare 受益人的 5%随机样本的理赔数据，我们确定了在 2013 年至 2014 年期间新诊断为房颤并开始使用 NOAC（n=8659）、华法林（n=11771）或未接受口服抗凝治疗（n=18226）的患者。每位患者根据其邮政编码被分配到 306 个 Dartmouth 医院转诊区域之一。我们构建了逻辑回归模型，以计算每个医院转诊区域内接受口服抗凝治疗的患者开始口服抗凝治疗的平均调整后概率和开始使用 NOAC 的平均调整后概率，同时调整了人口统计学、临床和提供者特征以及保险类型。最后，我们计算了这两个概率之间的相关性。
中西部（0.54）和东北部（0.54）的平均调整后开始口服抗凝治疗的概率较高，而南部（0.47）则较低，为 0.51，范围为 0.32 至 0.72。接受口服抗凝治疗的患者中，处方 NOAC 的平均调整后概率为 0.42，南部（0.50）最高，中西部（0.36）和东北部（0.39）最低。在口服抗凝药物使用率较低的地区，接受任何口服抗凝治疗的患者更有可能被处方 NOAC（相关系数，-0.16；=0.006）。
在房颤患者中，口服抗凝药物的使用存在较大的地域差异。在南部地区，口服抗凝药物的使用较低，而该地区的卒中发生率异常高。在未来，分析南部地区如此高的卒中发生率是否部分归因于该地区口服抗凝药物的使用率较低将非常重要。
