論文No906
Oral Anticoagulation and the Risk of Stroke or Death in Patients With Atrial Fibrillation and One Additional Stroke Risk Factor:
The Loire Valley Atrial Fibrillation Project
Laurent Fauchier, MD; Coralie Lecoq, MD; Nicolas Clementy, MD; Anne Bernard, MD; Denis Angoulvant, MD; Fabrice Ivanes, MD; Dominique Babuty, MD; Gregory Y.H. Lip, MD
Chest. 2016;149(4):960-968. doi:10.1378/chest.15-1622
＜背景＞
心房細動（ＡＦ）患者と別の単一の脳梗塞リスク因子（うっ血性心不全、高血圧、７５歳以上、糖尿病、以前の梗塞／血栓塞栓の既往、血管疾患、６５－７４歳、性別：（CHA2DS2-VAScが男性で１、女性で２））があると
経口抗凝固薬（ＯＡＣ）で治療すべきかどうかはいまだ不明である。
我々はＡＦと０から１つのCHA2DS2-VAScスコアのある患者のコホート集団における虚血性脳梗塞、全身性塞栓、死亡のリスクを調べた。
＜方法＞
２０００年から２０１０年のＡＦ患者８９６２名において、
２１７７名（２４％）が０から１つの脳梗塞のリスク因子をもち、うち５３％はすでにＯＡＣを投与されていた。
＜結果＞
フォローアップ期間979 ± 1,158 日において、１５１名（７％）が重大イベント（脳梗塞／全身性血栓塞栓／死亡）を起こした。
ＯＡＣの処方は低リスク群（CHA2DS2-VAScスコアが男性では０、女性では１）では脳梗塞／全身性血栓塞栓／死亡によい影響をもたなかった。
１つのリスク因子のある群（CHA2DS2-VAScスコアが男性では１、女性では２）では
ＯＡＣは脳梗塞／全身性血栓塞栓／死亡によい影響があった（ハザード比０．５９、ｐ＝0.007）。
＜感想＞
ＡＦ以外にリスクのない場合、ＯＡＣの投与は不要。一方、１つでもリスク因子があるとＯＡＣは意義があるようです。
Background It remains uncertain whether patients with atrial fibrillation (AF) and a single additional stroke risk factor (congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, prior stroke or thromboembolism, vascular disease, age 65-74 years, and sex category [CHA2DS2-VASc] score = 1 in men, 2 in women) should be treated with oral anticoagulation (OAC). We investigated the risk of ischemic stroke, systemic embolism, and death in a community-based cohort of unselected patients with AF with zero to one stroke risk factor based on the CHA2DS2-VASc score.
Methods Among 8,962 patients with AF seen between 2000 and 2010, 2,177 (24%) had zero or one additional stroke risk factor, of which 53% were prescribed OAC.
Results Over a follow-up of 979 ± 1,158 days, 151 (7%) had a major adverse event (stroke/systemic thromboembolism/death). Prescription of OAC was not associated with a better prognosis for stroke/systemic thromboembolism/death for patients in the “low-risk” category (ie, CHA2DS2-VASc score = 0 for men or 1 for women; adjusted hazard ratio [HR], 0.68; 95% CI, 0.35-1.31; P = .25). OAC use was independently associated with a better prognosis in patients with AF with a single additional stroke risk factor (ie, CHA2DS2-VASc score = 1 in men, 2 in women; adjusted HR, 0.59; 95% CI, 0.40-0.86; P = .007).
Conclusions Among patients with AF with a single additional stroke risk factor (CHA2DS2-VASc score = 1 in men, 2 in women), OAC use was associated with an improved prognosis for stroke/systemic thromboembolism/death.