Table 2.

Adjusted Hazard Ratios for the Primary End Point and Its Components for Final Cox Regression Model

	Warfarin		Aspirin		Adjusted Hazard Ratio (95%) CI) for Warfarin vs Aspirin	P Value
	Events, %	Rate*	Events, %	Rate*		For HR†	For Interaction
<60 y	n=508	1935.0 pt-years	n=522	1924.2 pt-years
Primary composite	93 (18.3)	4.81	130 (24.9)	6.76	0.63 (0.48–0.84)	0.001	0.003
Ischemic stroke	12 (2.4)	0.62	26 (5.0)	1.35	0.51 (0.32–0.81)	0.005	0.64‡
Intracerebral hemorrhage	2 (0.4)	0.10	0 (0.0)	0.00	2.35 (0.44–12.48)	0.32	…§
Death	79 (15.6)	4.08	104 (19.9)	5.40	0.65 (0.48–0.89)	0.007	0.003
≥60 y	n=634	2109.7 pt-years	n=641	2108.6 pt-years
Primary composite	209 (33.0)	9.91	190 (29.6)	9.01	1.09 (0.88–1.35)	0.44	0.003
Ischemic stroke	17 (2.7)	0.81	29 (4.5)	1.38	0.51 (0.32–0.81)	0.005	0.64‡
Intracerebral hemorrhage	3 (0.5)	0.14	2 (0.3)	0.09	2.35 (0.44–12.48)	0.32	…§
Death	189 (29.8)	8.96	159 (24.8)	7.54	1.18 (0.94–1.49)	0.16	0.003

6MW indicates 6-minute walk; BMI, body mass index; BUN, blood urea nitrogen; CI, confidence interval; DBP, diastolic blood pressure; HR, hazard ratio; ICH, intracerebral hemorrhage; NYHA, New York Heart Association; and PVD, peripheral vascular disease.

^*Rates are per 100 patient-years.

^†From Cox models stratified by site, prior stroke status, and NYHA classification. HRs for composite end point, death, and stroke are adjusted for age category, sex, diabetes mellitus, PVD, BMI, BUN, ejection fraction, DBP, 6MW, and hemoglobin. HRs for ICH adjusted for age category. Treatment-by-age category interaction terms are included as applicable.

^‡Hazard ratios are from models without treatment×age category interaction term for ischemic stroke, given no evidence of treatment×age category interaction.

^§Not enough events to test for interaction. HR is from the model without a treatment×age category term.