Efficacy and safety outcomes of patients with atrial fibrillation compared between warfarin and non-vitamin K antagonist oral anticoagulants based on SAMe-TT2R2 score

Table 2 Incidence of primary and secondary outcomes compared between the warfarin with NOAC groups among all patients taking OAC, as well as patients with a low and high SAMe-TT2R2 score

Outcomes	All OAC (N = 2568)
	Warfarin (n = 2340)		NOACs (n = 228)		HR (95%CI)	p value
	Number of events n (%)	Incidence per 100 person-years	Number of events n (%)	Incidence per 100 person-years	HR (95%CI)	p value
Primary efficacy outcome^a	305 (13.0%)	5.32	21 (9.2%)	3.45	1.54 (0.99–2.40)	0.055
All-cause death	257 (11.0%)	4.49	16 (7.0%)	2.60	1.71 (1.03–2.83)	*0.038*
IS/TIA and/or SE	86 (3.7%)	1.49	5 (2.2%)	0.82	1.83 (0.74–4.50)	0.190
Primary safety outcome^b	155 (6.6%)	2.72	11 (4.8%)	1.82	1.50 (0.81–2.76)	0.198
Intracranial hemorrhage	57 (2.4%)	1.0	5 (2.2%)	0.82	1.19 (0.48–2.97)	0.708
Extracranial major bleeding	98 (4.2%)	1.9	6 (2.6%)	1.01	1.88 (0.82–4.28)	0.135
Secondary outcome
CV death^c	21 (0.9%)	0.36	0 (0.0%)	0	–	–
CV death^c or IS/TIA/SE	155 (6.6%)	2.69	10 (4.4%)	1.64	1.64 (0.87–3.11)	0.130
CV death3, IS/TIA/SE or major bleeding	267 (11.4%)	4.75	17 (7.5%)	2.83	1.68 (1.03–2.74)	*0.039*

Outcomes	OAC-Low SAMe-TT₂R₂ (n = 617)
	Warfarin (n = 558)		NOACs (n = 59)		HR (95%CI)	p value
	Number of events n (%)	Incidence per 100 person-years	Number of events n (%)	Incidence per 100 person-years	HR (95%CI)	p value
Primary efficacy outcome^a	60 (10.8%)	4.49	4 (6.8%)	2.46	1.81 (0.66–4.97)	0.252
All-cause death	54 (9.7%)	4.01	4 (6.8%)	2.46	1.61 (0.58–4.45)	0.358
IS/TIA and/or SE	13 (2.3%)	0.97	0 (0.0%)	0	–	–
Primary safety outcome^b	41 (7.3%)	3.11	5 (8.5%)	3.13	1.00 (0.40–2.53)	0.999
Intracranial hemorrhage	20 (3.6%)	1.49	3 (5.1%)	1.87	0.79 (0.23–2.65)	0.700
Extracranial major bleeding	21 (3.8%)	1.71	2 (3.4%)	1.25	1.43 (0.34–6.09)	0.630
Secondary outcome
CV death^c	5 (0.9%)	0.37	0 (0.0%)	0	–	–
CV death^c or IS/TIA/SE	29 (5.2%)	2.16	1 (1.7)	0.62	3.49 (0.48–25.64)	0.219
CV death^c, IS/TIA/SE or major bleeding	58 (10.4%)	4.43	5 (8.5%)	3.13	1.42 (0.57–3.55)	0.448

Outcomes	OAC-High SAMe-TT₂R₂ (n = 1951)
	Warfarin (n = 1782)		NOACs (n = 169)		HR (95%CI)	p value
	Number of events n (%)	Incidence per 100 person-years	Number of events n (%)	Incidence per 100 person-years	HR (95%CI)	p value
Primary efficacy outcome^a	245 (13.7%)	5.58	17 (10.1%)	3.81	1.47 (0.89–2.40)	0.128
All-cause death	203 (11.4%)	4.56	12 (7.1%)	2.65	1.73 (0.96–3.09)	0.066
IS/TIA and/or SE	73 (4.1%)	1.65	5 (3.0%)	1.12	1.48 (0.60–3.67)	0.396
Primary safety outcome^b	114 (6.4%)	2.61	6 (3.6%)	1.35	1.93 (0.85–4.38)	0.117
Intracranial hemorrhage	37 (2.1%)	0.83	2 (1.2%)	0.44	1.86 (0.45–7.71)	0.394
Extracranial major bleeding	77 (4.3%)	1.94	4 (2.4%)	0.92	2.10 (0.77–5.74)	0.148
Secondary outcome
CV death^c	16 (0.9%)	0.36	0 (0.0%)	0	–	–
CV death^c or IS/TIA/SE	126 (7.1%)	2.85	9 (5.3%)	2.02	1.42 (0.72–2.78)	0.314
CV death^c, IS/TIA/SE or major bleeding	209 (11.7%)	4.85	12 (7.1%)	2.72	1.78 (1.00–3.18)	0.052

NOAC non-vitamin K antagonist oral anticoagulant, OAC oral anticoagulant, HR hazard ratio, CI confidence interval, IS ischemic stroke, TIA transient ischemic attack, SE systemic embolism, CV cardiovascular, SAMe-TT₂R₂ score, S female sex (1 point), A age < 60 years (1 point), Me medical history > 2 of the following: hypertension, diabetes, coronary artery disease/myocardial infarction, peripheral arterial disease, congestive heart failure, previous stroke, pulmonary disease, and hepatic or renal disease (1 point), T treatment (interacting drugs, e.g., amiodarone for rhythm control) (1 point), T₂ tobacco use within 2 years (2 points), R₂ non-Caucasian race (2 points)
A p value < 0.05 indicates statistical significance (bold and italic)
^aPrimary efficacy outcome, including death, IS/TIA, and/or SE
^bPrimary safety outcome, including major bleeding
^cCV death, including IS/TIA, myocardial infarction, and/or SE

ISSN: 1471-2261