Table 3. Associations of exhaled carbon monoxide and incident stroke/TIA.

	Whole sample (N=3313)
	CO ≤4 ppm	p value	CO >4 and ≤5 ppm	p value	CO >5 ppm	p value	p for trend
Model 1, HR (95% CI)	Referent	--	1.67 (1.20-2.32)	0.0022	1.97 (1.41-2.76)	<0.0001	<0.0001
Model 2, HR (95% CI)	Referent	--	1.60 (1.15-2.23)	0.0053	1.43 (0.96-2.14)	0.08	0.04
Model 3, HR (95% CI)	Referent	--	1.57 (1.12-2.20)	0.0083	1.45 (0.97-2.17)	0.07	0.04
	Nonsmokers (N=2819)
Model 1, HR (95% CI)	Referent	--	1.69 (1.21-2.35)	0.0019	1.63 (1.09-2.44)	0.02	0.0056
Model 2, HR (95% CI)	Referent	--	1.68 (1.20-2.35)	0.0025	1.55 (1.03-2.33)	0.04	0.01
Model 3, HR (95% CI)	Referent	--	1.66 (1.18-2.34)	0.0036	1.57 (1.04-2.38)	0.03	0.01

TIA indicates transient ischemic attack; CO, carbon monoxide; ppm, parts per million; HR, hazard ratio; CI, confidence interval.

HR represents the relative hazard for each CO category compared with the referent.

Model 1 was adjusted for age and sex.

Model 2 was additionally adjusted for systolic blood pressure, hypertension treatment status, diabetes, total/HDL cholesterol, body mass index, smoking, prevalent cardiovascular disease, prevalent atrial fibrillation.

Model 3 was additionally adjusted for log-BNP and log-CRP. N=3189 for the whole sample and N=2715 for nonsmokers.