Stage 1 hypertension, sex, and acute coronary syndromes during midlife: the Hordaland Health Study

Hypertension has been suggested as a stronger risk factor for acute coronary syndromes (ACS) in women than men. Whether this also applies to stage 1 hypertension [blood pressure (BP) 130–139/80–89 mmHg] is not known.

We tested associations of stage 1 hypertension with ACS in 12 329 participants in the Hordaland Health Study (mean baseline age 41 years, 52% women). Participants were grouped by baseline BP category: Normotension (BP < 130/80 mmHg), stage 1 and stage 2 hypertension (BP ≥140/90 mmHg). ACS was defined as hospitalization or death due to myocardial infarction or unstable angina pectoris during 16 years of follow-up. At baseline, a lower proportion of women than men had stage 1 and 2 hypertension, respectively (25 vs. 35% and 14 vs. 31%, P < 0.001). During follow-up, 1.4% of women and 5.7% of men experienced incident ACS (P < 0.001). Adjusted for diabetes, smoking, body mass index, cholesterol, and physical activity, stage 1 hypertension was associated with higher risk of ACS in women [hazard ratio (HR) 2.18, 95% confidence interval (CI) 1.32–3.60], while the association was non-significant in men (HR 1.30, 95% CI 0.98–1.71). After additional adjustment for systolic and diastolic BP, respectively, stage 1 diastolic hypertension was associated with ACS in women (HR 2.79 [95% CI 1.62-4.82]), but not in men (HR 1.24 [95% CI 0.95-1.62]), while stage 1 systolic hypertension was not associated with ACS in either sex.

Among subjects in their early 40s, stage 1 hypertension was a stronger risk factor for ACS during midlife in women than in men.