Appendix Table 7.

Hospitalizations for upper gastrointestinal bleeding during warfarin treatment according to study population, PPI co-therapy, history of upper gastrointestinal bleeding risk factors^a, and concurrent use of antiplatelet drugs/NSAIDs. HR = adjusted hazard ratio, RD = adjusted rate difference per 10,000, CI = confidence interval.

a. Tennessee Medicaid
	No PPI Co-therapy			PPI Co-therapy			HR (95% CI)	RD (95% CI)
	Person- years	Hospital- izations	Rate /10,000	Person- years	Hospital- izations	Rate /10,000
No history risk factors
No concurrent antiplatelet drug/NSAID	21,468	141	65.7	3,211	22	68.5	1.02 ( 0.64 - 1.61 )	1.1 ( -23.4 to 39.9 )
Concurrent antiplatelet drug/NSAID	3,375	78	231.1	823	8	97.2	0.42 ( 0.20 - 0.87 )	-134.4 ( -184.7 to -29.5 )
History risk factors
No concurrent antiplatelet drug/NSAID	11,050	169	152.9	4,219	65	154.1	0.87 ( 0.64 - 1.19 )	-19.3 ( -54.6 to 28.6 )
Concurrent antiplatelet drug/NSAID	1,733	64	369.4	1,036	30	289.6	0.69 ( 0.44 - 1.08 )	-115.4 ( -207.3 to 28.5 )
b. Medicare 5% Sample
	No PPI Co-therapy			PPI Co-therapy			HR (95% CI)	RD (95% CI)
	Person- years	Hospital- izations	Rate /10,000	Person- years	Hospital- izations	Rate /10,000
No history risk factors
No concurrent antiplatelet drug/NSAID	8,581	62	72.2	1,999	10	50.0	0.71 ( 0.36 - 1.39 )	-21.3 ( -46.2 to 27.8 )
Concurrent antiplatelet drug/NSAID	599	11	183.7	218	2	91.8	0.50 ( 0.11 - 2.24 )	-92.7 ( -163.6 to 228.2 )
History risk factors
No concurrent antiplatelet drug/NSAID	5,140	77	149.8	2,840	37	130.3	0.81 ( 0.54 - 1.22 )	-28.5 ( -69.4 to 33.2 )
Concurrent antiplatelet drug/NSAID	461	22	477.4	313	7	223.3	0.48 ( 0.20 - 1.13 )	-250.6 ( -381.6 to 59.7 )

^aRisk factors: Peptic ulcer, gastritis, abdominal pain, blood in stool/GI bleeding, anemia