Is high-normal blood pressure a more important risk factor for cardiovascular disease in women than in men? The Hordaland Health study

Abstract

Abstract Background Hypertension is a major risk factor for cardiovascular disease (CVD), but the definition of hypertension is currently debated. Little is known about whether high-normal blood pressure (BP) carries a different risk for CVD in women and men. Purpose The aim of the current study was to test associations of high-normal BP with CVD in women and men participating in the community-based Hordaland Health Study (HUSK). Methods Data from 8252 participants aged 40–43 years (52% women) participating in the HUSK survey in 1992–93 were coupled with hospitalization or death from CVD documented by ICD codes in national registries in the period 1994–2009. Attended BP was measured in accordance with current guidelines. The average of the two last measurements was taken as the clinic BP measure. The cohort was grouped into normal BP (BP<130/85 mmHg), high-normal BP (BP 130–139/85–89 mmHg) and hypertension (BP≥140/90 mmHg or use of antihypertensive drugs). CVD was defined as hospitalization or death from any CVD diagnosis. The association between BP category and CVD was tested in sex-specific Cox regression analyses, using normal BP as the reference group and adjusting for diabetes, smoking, body mass index and total cholesterol. Results At baseline, 17% women and 27% men had high-normal BP and 16% women and 32% men had hypertension (both p<0.001 between sexes). During 16 years follow-up, 15% of women and 22% of men experienced hospitalization or death from CVD (p<0.001). A significant sex-interaction of BP group and outcome was found (p<0.05). In multivariable analyses in women, both hypertension and high-normal BP were associated with incident CVD (both p<0.01) independent of confounders (Table). In men, only hypertension was associated with incident CVD in the same model, while high-normal BP was not (p<0.001 and p=0.53, respectively) (Table). Conclusion High-normal BP was a more important risk factor for CVD in middle-aged women than men. Our findings challenges whether hypertension-associated CVD risk is optimally detected in women by the current hypertension definition in European guidelines. Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): University of Bergen