Another problem is that the indications of
Another problem is that the indications of each drug differ among Asia-Pacific countries, and it orexin agonist is difficult to provide recommendations that are consistent with the indications in each country. For example, in Japan, the 3 novel OACs are indicated for “the prevention of ischemic stroke and systemic embolism in patients with nonvalvular AF” regardless of the results of the risk assessment according to the CHADS2 score. The National Health Insurance system in Japan covers the use of these drugs even when they are prescribed to patients with a CHADS2 score of 0.
According to these circumstances, the APHRS 2013 statement (Table 3) lists dabigatran, rivaroxaban, and apixaban separately, and describes the use of each of these drugs with warfarin in order to help physicians in Asia-Pacific countries prescribe these drugs appropriately, to ensure optimal anticoagulant therapy in each patient when these drugs are approved in the relevant country. We hope that physicians will make the most of the statement in accordance with the health-care policy in each country.
Positioning of ASA Another important point in Table 2 is that the weight of ASA differs across different guidelines. While the JCS 2008 guidelines do not recommend ASA for patients with AF and the CCS 2012 guidelines do not recommend ASA for patients with a CHADS2 score of 0 and without clinically relevant nonmajor factors, other guidelines recommended ASA for patients with a CHADS2 score of 0/1. Since it has been reported that bleeding complications of ASA are more common in Asian patients [22,23], guidelines appropriate for patients in Asia-Pacific countries are awaited. The ESC 2010 and CCS 2012 guidelines recommend HAS-BLED (Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile INRs, elderly [≥65], and drugs/alcohol concomitantly) as an indicator of the risk of bleeding. ASA rather than warfarin has tended to be recommended for patients with a high risk of bleeding. It is difficult to assess the net benefit of antithrombotic therapy in elderly patients in whom the risks of stroke and bleeding are high. However, the recently reported results of the Danish National Patient Registry  did not support a favorable net clinical benefit of ASA monotherapy in patients with a high risk of bleeding. These findings suggest maximum sustainable yield (MSY) guidelines for patients in Asia-Pacific countries should not recommend ASA, as the JCS 2008 guidelines do not. The ESC guidelines have issued a 2012-focused update  and clearly denied the use of ASA for patients with CHA2DS2-VASc score of 0. ASA should be considered in patients who refuse any OAC, or cannot tolerate anticoagulants.
As Fig. 1 shows, the results of the APHRS survey revealed differences among physicians in the 9 participating countries in terms of the dependency on the CHADS2 and CHA2DS2-VASc scores in risk assessment of patients with AF. More than 50% of physicians in Australia, India, New Zealand, and Singapore are using the CHA2DS2-VASc score, whereas users of the CHADS2 score accounted for ≥50% in Japan, Taiwan, and Hong Kong. Of note, 70% of physicians in Japan use the CHADS2 score, whereas 86% of physicians in New Zealand use the CHA2DS2-VASc score to assess the risk of AF patients. Considering the underuse of OACs and the overuse of ASA among patients with a CHADS2 score of 0/1 (see below for detail), the CHA2DS2-VASc score should be adopted in the APHRS\'s statement. The use of antithrombotic therapy according to the CHADS2 score differed significantly among the 9 countries (Figs. 2–5). In patients with a CHADS2 score of 0 (Fig. 2), the frequency of use of OACs (including novel OACs) was extremely low (11%), and in most cases, antiplatelet agents are used (63%). In patients with a CHADS2 score of 1, OACs and antiplatelet agents were used by approximately half of the physicians each (41% vs. 49%, respectively). In contrast, for patients with a CHADS2 score of 2, OACs (including warfarin, direct thrombin inhibitor, and their concomitant use with antiplatelets) were used at an unexpectedly high percentage, namely as high as 87% of the physicians.