Table 3.

Relative risk (95% group-specific confidence interval [g-sCI]) of incident coronary heart disease and stroke in parous women, by reported history of hypertension during pregnancy and treatment for hypertension at baseline.

Incident vascular disease (ICD-10)	Hypertension during pregnancy	Being treated for hypertension at baseline	No. with outcome	Relative risk (95% g-sCI)
Coronary heart disease (I20 to I25)
	No	No	33,884	1.00 (0.99 to 1.01)
	Yes	No	8999	1.17 (1.14 to 1.19)
	No	Yes	12,696	1.61 (1.59 to 1.64)
	Yes	Yes	12,582	1.78 (1.76 to 1.82)
Ischaemic stroke (I63)
	No	No	4077	1.00 (0.97 to 1.03)
	Yes	No	1056	1.18 (1.11 to 1.25)
	No	Yes	1707	1.77 (1.69 to 1.86)
	Yes	Yes	1525	1.86 (1.76 to 1.96)
Haemorrhagic stroke (I60 to I62)
	No	No	3184	1.00 (0.96 to 1.04)
	Yes	No	760	1.09 (1.02 to 1.18)
	No	Yes	980	1.60 (1.50 to 1.71)
	Yes	Yes	778	1.48 (1.38 to 1.59)

ICD-10 — International Classification of Diseases, 10th Revision; relative risks are hazard ratios estimated using Cox regression with age as the underlying time variable, stratified by region of recruitment, and adjusted for smoking, socioeconomic status, exercise, alcohol intake, body mass index, parity, ever use of hormone replacement therapy, treatment for diabetes, and treatment for hypercholesterolaemia at baseline; reference group: no history of hypertensive pregnancy and not on anti-hypertensive treatment at baseline.