Table 2.

Incidence Rates and Multivariate-Adjusted Hazard Ratios and 95% Confidence Intervals (95% CI) of Intracerebral Hemorrhage (ICH) According to Carotid Intima-Media Thickness (IMT) and Carotid Plaque, ARIC and CHS

		Quartile of IMT†				Per 1 SD increment of IMT‡	Carotid Plaque
		1	2	3	4		No	Yes
ARIC	IMT quartile range (mm)	<0.62	0.62–0.70	0.70–0.81	>0.81
	n ICH/N at risk	6/3,269	18/3,270	16/3,270	29/3,270	--	40/8,690	29/4,389
	Incidence Rate§	1.0	3.1	2.8	5.5	--	2.6	4.0
	Model 1 Hazard Ratio*	1.0	2.73	2.37	4.26	1.39	1.0	1.35
	95% CI	--	1.08–6.91	0.92–6.14	1.71–10.6	1.15–1.68	--	0.83–2.22
	Model 2 Hazard Ratio**	1.0	2.64	2.21	3.70	1.34	1.0	1.24
	95% CI	--	1.04–6.67	0.85–5.72	1.48–9.28	1.10–1.63	--	0.76–2.04
CHS	IMT quartile range (mm)	<0.98	0.98–1.17	1.17–1.44	>1.44
	n ICH/N at risk	18/1,269	27/1,269	21/1,269	27/1,269	--	15/1,124	78/3,952
	Incidence Rate§	10.0	16.2	13.9	21.6	--	9.5	16.8
	Model 1 Hazard Ratio*	1.0	1.82	1.67	2.77	1.25	1.0	2.05
	95% CI	--	0.99–3.33	0.88–3.18	1.48–5.18	1.01–1.55	--	1.17–3.58
	Model 2 Hazard Ratio**	1.0	1.76	1.56	2.49	1.19	1.0	1.95
	95% CI	--	0.96–3.22	0.82–2.98	1.33–4.69	0.96–1.48	--	1.11–3.42

^†IMT quartiles were study-specific.

^‡One SD of IMT was ARIC: 0.19 mm and CHS: 0.34 mm

^§Crude incidence rate per 10,000 person-years

^*Adjusted for age (continuous), race (African American, white), current smoking (yes, no), LDL cholesterol (continuous), natural log triglycerides (continuous), and fibrinogen (continuous).

^**Adjusted for Model 1 variables plus systolic blood pressure (continuous)