Study population
From June 2012 to December 2013, the XANTUS study enrolled 6784 patients across Europe, Israel, and Canada; the ETNA-AF-EU study enrolled 13,092 patients between November 2016 and February 2018 across 10 European countries (Austria, Belgium, Germany, Ireland, Italy, The Netherlands, Portugal, Spain, Switzerland and UK). Patients were routinely assigned to receive rivaroxaban or edoxaban, respectively. After the exclusion of patients who withdrew consent, or were lost to follow-up, a total of 19,876 patients were followed for 12 months. Baseline characteristics are as shown (Table 1). Patients in the XANTUS were significantly younger (71.5% vs 73.6%, p = 0.0009), when compared to the ETNA-AF-EU cohort. When comparing by age group, the XANTUS cohort had a higher proportion of patients < 65 years old (21.8% vs 15.2%, p = 0.00001); and patients between 65–74 years (41% vs 34%, p = < 0.00001). ETNA-AF-EU had a higher proportion of patients with 75 years or more (50.7% vs 37.2%, p = < 0.00001). Of note, ETNA-AF-EU had 89% and 10% of patients respectively less than 85 years old and more than 85 years old. The XANTUS cohort did not include patients in this age range.
Table 1
Patients Baseline Characteristics
|
XANTUS
n = 6,784
|
ETNA-AF-Europe
n = 13,092
|
P-value
Comparison among studies
|
Male, n (%)
|
4,016 (59.2%)
|
7,430 (56.8%)
|
0.0009
|
Age (years), mean ± SD
|
71.5 ± 10.0
|
73.6 ± 9.46
|
< 0.00001
|
By age sub-groups, n (%)
|
|
< 65 years
|
1,478 (21.8%)
|
1,994 (15.2%)
|
< 0.00001
|
65–74 years
|
2,782 (41.0%)
|
4,456 (34.0%)
|
< 0.00001
|
≥75 years
|
2,524 (37.2%)
|
6,640 (50.7%)
|
< 0.00001
|
< 85 years
|
NA
|
11,718 (89.5%)
|
-
|
≥85 years
|
NA
|
1,372 (10.5%)
|
-
|
Body weight (kg), mean ± SD
|
83.0 ± 17.3
|
81.0 ± 17.29
|
< 0.00001
|
BMI (kg/m2), mean ± SD
|
28.3 ± 5.0
|
28.1 ± 5.11
|
0.008
|
CrCl (mL/min), mean ± SD
|
NA
|
74.3 ± 30.42
|
-
|
Co-morbidities, n (%)
|
|
Hypertension
|
5065 (74.7%)
|
10088 (77.1%)
|
0.0002
|
Diabetes mellitus
|
1333 (19.6%)
|
2879 (22.0%)
|
0.0001
|
Congestive HF
|
1265 (18.6%)
|
777 (5.9%)
|
< 0.00001
|
Myocardial Infarction
|
688 (10.1%)
|
560 (4.3%)
|
< 0.00001
|
Previous history of stroke and ICH, n (%)
|
|
Ischaemic stroke
|
1291 (19.0%)
|
778 (5.9%)
|
< 0.00001
|
Intracranial haemorrhage
|
NA
|
62 (0.5%)
|
-
|
Previous history of bleeding, n (%)
|
|
Major
|
NA
|
129 (1.0%)
|
-
|
Major or CRNM
|
NA
|
270 (2.1%)
|
-
|
AF type, n (%)
|
|
First diagnosed
|
1,253 (18.5%)
|
NA
|
-
|
Paroxysmal
|
2,757 (40.6%)
|
7,039 (53.9%)
|
< 0.00001
|
Persistent
|
923 (13.6%)
|
3,159 (24.2%)
|
< 0.00001
|
Permanent †
|
1,835 (27.0%)
|
2,864 (21.9%)
|
< 0.00001
|
CHADS2, mean ± SD
|
2.0 ± 1.3
|
1.7 ± 1.07
|
< 0.00001
|
CHA2DS2-VASc, mean ± SD
|
2.0 ± 1.3
|
3.1 ± 1.40
|
< 0.00001
|
AF, atrial fibrillation; † In XANTUS group includes both (paroxysmal and non-paroxysmal). NA, Not Applicable; BMI, Body Mass Index; CHADS, congestive heart failure, hypertension, age > 75 years, diabetes; previous stroke, CHADSVASC, congestive heart failure, hypertension, age > 75 years, diabetes; previous stroke; Vascular disease; crnm, clinically relevant non-major, HF, heat failure, CrCl, Creatinine clearance, SD, standard Deviation. |
Patients in the XANTUS cohort had a significantly higher body weight and body mass index, p = < 0.00001 and p = 0.008, respectively.
Known history of hypertension and diabetes mellitus were significantly lower in the XANTUS cohort when comparing with ETNA-AF-EU cohort, (74% vs 77.1%, p = 0.0002) and (19.6% vs 22%, p = 0.0001), respectively. Known congestive heart failure and myocardial infarction were higher in the XANTUS cohort (18.6% vs 5.9%, p = < 0.00001, and 10.1% vs 4.3%, p = < 0.00001, respectively).
Previous ischemic stroke was significantly more frequent in the XANTUS cohort (19% vs 5.9%, p = < 0.00001).
Regarding AF type at baseline, paroxysmal and persistent types were significantly lower in the XANTUS cohort (40.6% vs 53.9%, p = < 0.00001, and 13.6% vs 24.2%, p = < 0.00001, respectively). Permanent AF was more prevalent in the XANTUS cohort (27% vs 21.9%, p = < 0.00001). CHA2DS2-VASc was significantly lower in the XANTUS cohort (p = < 0.00001).
Efficacy outcomes
All-cause mortality at 1 year was significantly lower in the XANTUS cohort. Death occurred in 442 of 13092 patients (3.5%) in the ETNA-AF-EU vs 118 of 6784 (1.7%) in the XANTUS cohort (p = < 0.00001, Table 2). The overall all-cause mortality odds ratio was 1.97 (95% confidence interval [CI], 1.61 to 2.42; p = < 0.00001). The same trend was noted for cardiovascular mortality, 206 of 13092 (1.63%) vs 49 of 6784 (0.72%) patients (OR, 2.20; 95% CI, 1.61 to 3.00; p = < 0.00001) for ETNA-AF-EU vs XANTUS, respectively.
Table 2
Outcomes in XANTUS and ETNA-AF
|
XANTUS
n = 6,784
|
ETNA-AF-Europe
n = 13,092
|
P-value
Between studies
|
All-cause mortality, n (%)
|
118 (1.7%)
|
442 (3.5%)
|
< 0.00001
|
Cardiovascular mortality, n (%)
|
49 (0,72%)
|
206 (1.63%)
|
< 0.00001
|
Thromboembolic events, n (%)
|
|
Stroke ischaemic, n (%)
|
32 (0.5%)
|
70 (0.56%)
|
0.56
|
Transient ischaemic attack, n (%)
|
32 (0.5%)
|
NA
|
-
|
Systemic embolism, n (%)
|
8 (0.1%)
|
103 (0.82%)
|
< 0.00001
|
Myocardial infarction, n (%)
|
27 (0,4)
|
66 (0.52%)
|
0.30
|
CNS Bleeding
|
|
Haemorrhagic stroke, n (%)
|
11 (0.2%)
|
14 (0.11%)
|
0.30
|
Intracranial haemorrhage, n (%)
|
26(0.4%)
|
30 (0.24%)
|
0.05
|
Major bleeding, n (%)
|
128 (1.9%)
|
132 (1.05%)
|
< 0.00001
|
CRNM bleeding, n (%)
|
878 (12.9%)
|
293 (2.35%)
|
< 0.00001
|
Major GI bleeding, n (%)
|
52 (0.8%)
|
51 (0.40%)
|
0.00006
|
TIA, transient ischaemic attack; SE, systemic embolism; MI, myocardial infarction; CNS, Central Nervous System; CRNM, Clinically Relevant Non-major bleeding (GI, gastrointestinal; ICH, intracranial haemorrhage). a. XANTUS includes combined results of both stroke/SE + SE |
Myocardial infarction, Ischemic stroke and systemic embolism were more common in the ETNA-AF-EU cohort when compared to the XANTUS cohort (Table 2)., but only systemic embolism was significantly higher in the ETNA-AF-EU cohort (OR, 6.72; 95% CI, 3.27 to 13.80; p = < 0.00001) (Fig. 3). The overall efficacy outcome favours the XANTUS cohort (p = 0.0002; I2 = 82%).