Atrial fibrillation (AF) is a documented risk factor for dementia. However, it is unclear whether oral anticoagulant (OAC) treatment can reduce the development of dementia or cognitive impairment. We conducted a systematic review and meta-analysis of the association between OAC use and subsequent dementia development in AF patients by searching databases from their inception to February 2018 without language restriction. Six studies (one randomized controlled trial and five observational studies) met the inclusion criteria. The pooled adjusted risk ratios (RRs) suggested a protective effect of OAC use in reducing dementia risk (RR 0.79 [95% CI: 0.67 – 0.93], I² = 59.7%; P = 0.005). Further, high percentage of time in therapeutic range (TTR) was associated with a decreased risk of dementia (RR 0.38 [95% CI 0.22-0.64], I² = 81.8%; P < 0.001). Our results support the hypothesis that AF-related dementia may be due to silent brain infarcts and micro-embolism that could be prevented by OAC use. Future studies with prospective follow-up with direct comparison of vitamin K antagonists and direct oral anticoagulants are needed.

心房纤颤（AF）是痴呆症的有据可证的危险因素。但是，尚不清楚口服抗凝剂（OAC）的治疗是否可以减少痴呆症或认知障碍的发生。我们通过搜索从开始到2018年2月无语言限制的数据库，对房颤患者的OAC使用与随后的痴呆症发展之间的关联进行了系统的回顾和荟萃分析。六项研究（一项随机对照试验和五项观察性研究）符合纳入标准。综合调整后的风险比（RRs）表明，使用OAC可以降低痴呆风险（RR 0.79 [95％CI：0.67 – 0.93]，I ²  = 59.7％；P = 0.005）。此外，高治疗时间范围（TTR）与痴呆风险降低相关（RR 0.38 [95％CI 0.22-0.64]，I ²  = 81.8％；P  <0.001）。我们的研究结果支持以下假设：与AF相关的痴呆可能归因于OAC的使用可以预防无声的脑梗塞和微栓塞。需要对未来的研究进行前瞻性随访，并直接比较维生素K拮抗剂和直接口服抗凝药。