Table 2.

Clinical outcomes between the patients with atrial fibrillation and atrial flutter not receiving warfarin therapy before and after PSM.

Variable	Before PSM			After PSM
	AF (n = 232,425)	AFL (n = 7,569)	P-value	AF (n = 30,276)	AFL (n = 7,569)	P-value
Dementia
Number of events, n (%)	22,833 (9.82)	521 (6.88)		2,435 (8.04)	521 (6.88)
Incidence density§	3.04 (3.00–3.08)	2.05 (1.87–2.22)		2.33 (2.24–2.43)	2.05 (1.87–2.22)
Hazard ratio (95% CI)	1.52 (1.39–1.66)	Reference	<0.0001	1.14 (1.04–1.25)	Reference	0.0064
Ischemic stroke
Number of events, n (%)	18,475 (7.95)	297 (3.92)		2,095 (6.92)	297 (3.92)
Incidence density§	2.54 (2.50–2.58)	1.18 (1.04–1.31)		2.07 (1.98–2.16)	1.18 (1.04–1.31)
Hazard ratio (95% CI)	2.15 (1.92–2.42)	Reference	<0.0001	1.76 (1.56–1.98)	Reference	<0.0001

AF, atrial fibrillation; AFL, atrial flutter; PSM, propensity score matching.

§ Incidence density: number of events per 100 person-years.