Table 3.

Incidence rates and Cox regression for risk of first ischemic stroke in women and men with atrial fibrillation treated with ITT- or PP-warfarin, versus patients without ITT- or PP-warfarin treatment as referents.

	Events/At Risk (n, %)	Incidence Rate (95% CI)	Warfarin ITT br1>HR (95% CI)	Warfarin PP HR (95% CI)
				Model 1	Model 2	Model 3
First ischemic stroke
Women	768/5,248 (14.6%)	2.77 (2.58–2.98)	0.66 (0.46–0.97)	0.27 (0.21–0.33)	0.24 (0.17–0.34)	0.25 (0.18–0.36)
Men	697/6,269 (11.1%)	2.02 (1.88–2.18)	0.73 (0.55–0.96)	0.27 (0.22–0.33)	0.26 (0.20–0.33)	0.25 (0.19–0.32)

ITT denotes “Intention-to-treat”: prescription before the years of first stroke, or present among subjects not experiencing a stroke.

PP denotes “Per-protocol”: prescription the year before and the year of first stroke, or present among subjects not experiencing a stroke if present at least during three years, of at least 50% of actual years after first recorded year of AF, or during both 2006 and 2007.

Incidence rate per 100 Person-Years at Risk.

Model for warfarin ITT (with patients on PP-warfarin treatment excluded): fully adjusted (age, neighbourhood socioeconomic status, educational level, marital status, hypertension, CHD, CHF and diabetes, with interaction term between age and marital status)

Models for warfarin PP: Model 1 age-adjusted, Model 2 also adjusted for socioeconomic factors (neighbourhood socioeconomic status, educational level and marital status), and Model 3 also for co-morbidity (hypertension, CHD, CHF and diabetes).