High-normal blood pressure in midlife is a stronger predictor for development of hypertension in women than in men

Abstract

Background Identification of modifiable risk factors in midlife may optimize prevention of hypertension. Sex differences in the multifactorial development of hypertension is not well understood. Purpose To explore the associations of health factors in midlife, with incident hypertension 26 years later, in women and men. Methods In the community-based Hordaland Health Study (HUSK) 1025 women and 703 men were examined at age 42 years (baseline) and re-examined after 6 and 26 years. Patients with hypertension at baseline were excluded. Attended blood pressure (BP) was measured in triplets. High-normal BP was identified as BP 130–139/85–89 mmHg. Incident hypertension was identified as BP ≥140/90 mmHg or patient reported use of antihypertensive drugs on the last study visit. The association of health factors at baseline and changes during midlife, with incident hypertension at follow-up were explored in sex specific multivariable logistic regression analyses. Models were adjusted for baseline body mass index (BMI), high-normal BP, heart rate, physical activity, daily smoking, education, serum cholesterol, and serum triglycerides. Results are presented as odds ratios (OR), 95% confidence intervals (CI) and p-values. Results At baseline, average BP was 119/73 mmHg in women and 126/76 mmHg in men (p<0.001). A high-normal BP was found in 26% of women and 47% of men (p<0.001). After 26 years of follow-up, 39% of women and 45% of men had developed hypertension (p<0.05). In multivariable logistic regression analyses, high-normal BP at baseline, was the strongest predictor of incident hypertension in both sexes, but significantly stronger in women (OR 4.8, 95% CI 3.4–6.9) than in men (OR 2.1, 95% CI 1.5–2.8), p<0.01 for sex interaction (Table 1). Increase in BMI from first to second study visit was significantly associated with incident hypertension in both sexes (both p<0.01). And an increase in serum triglycerides from first to second visit was significant only in women (p<0.05). Conclusions High-normal BP in midlife was a particularly strong risk factor for development of hypertension later in life and significantly stronger in women. An increase in BMI in midlife was associated with incident hypertension but did not differ between sexes. Awareness of sex differences in modifiable health factors in midlife enable improved prevention of hypertension. Funding Acknowledgement Type of funding sources: Public Institution(s). Main funding source(s): University of Bergen