Table 3.

Risk of gastrointestinal bleeding with low-dose aspirin and paracetamol after propensity score matching

	Low-dose aspirin			Paracetamol			HR (95% CI)	P value
	No.	No. of cases/person-years	Incidence per 1000 person-years	No.	No. of cases/person-years	Incidence per 1000 person-years
Overall	49 679	5498/431 246	12.27	49 679	5131/465 091	11.03	1.15 (1.11 to 1.20)	<0.001
Female	24 031	2698/212 596	12.69	23 991	2510/229 792	10.92	1.16 (1.10 to 1.23)	<0.001
Male	25 648	2800/218 650	12.81	25 688	2621/235 300	11.14	1.15 (1.09 to 1.21)	<0.001
40–49 years old	4344	184/46 633	3.95	4002	190/45 506	4.18	0.94 (0.77 to 1.15)	0.56
50–59 years old	9350	526/97 488	5.40	8416	476/93 363	5.10	1.05 (0.93 to 1.19)	0.41
60–69 years old	11 489	1007/112 395	8.96	11 050	935/116 577	8.02	1.13 (1.03 to 1.23)	0.008
70–79 years old	14 976	2153/122 814	17.53	15 326	1742/141 851	12.28	1.44 (1.35 to 1.53)	<0.001
≥80 years old	9520	1628/51 916	31.36	10 885	1788/67 795	26.37	1.18 (1.11 to 1.27)	<0.001
Diabetes mellitus	6079	756/46 398	16.29	5975	752/49 701	15.13	1.07 (0.97 to 1.18)	0.20
PPI/H2-blocker use	14 323	1682/113 597	14.81	13 898	1738/122 015	14.24	1.03 (0.96 to 1.10)	0.46
Upper GIB	49 679	4964/431 246	11.51	49 679	4649/465 091	10.00	1.14 (1.09 to 1.18)	<0.001
PPI/H2-blocker use	14 323	1513/113 597	13.32	13 898	1612/122 015	13.21	0.98 (0.91 to 1.05)	0.54
Lower GIB	49 679	549/431 246	1.27	49 679	501/465 091	1.08	1.31 (1.16 to 1.48)	<0.001
PPI/H2-blocker use	14 323	176/113 597	1.55	13 898	131/122 015	1.07	1.70 (1.35 to 2.14)	<0.001

GIB, gastrointestinal bleeding; H2-blocker, histamine-2 receptor blocker; PPI, proton pump inhibitors.