Women and hypertension: what did we learn from the Women's Health Initiative?

The Women's Health Initiative (WHI) provides valuable data on blood pressure (BP) and on the prevalence, treatment, and control of hypertension in the largest multiethnic, best characterized cohort of postmenopausal women ever studied, including 98,705 women aged 50 to 79 years. Hypertension prevalence was high (38% overall) and directly related to age. Major determinants of hypertension prevalence included black race, history of cardiovascular disease (CVD), and concomitant CVD risk factors of physical inactivity, overweight/obesity, and excess alcohol consumption. Menopausal hormone treatment had little effect on BP. BP control rates declined dramatically with age. Interestingly, participants who were insured by Medicaid had significantly higher treatment rates and tended to have better BP control than those with Medicare only, perhaps reflecting differences in drug coverage and/or age. Inadequate intensity of antihypertensive treatment contributed to poor BP control: approximately 60% of participants were treated with a single drug; 30% with 2 drugs; <10% with 3 or more drugs, and the number of medications used was similar across age groups despite the age-related increase in the severity of hypertension. This treatment pattern is inconsistent with current treatment guidelines, which stress the need for 2 or more antihypertensive medications to control BP in most older hypertensive patients. The take-home message from WHI is that more effective strategies, including more efficient and cost-effective systems of healthcare delivery, are needed to control BP and prevent CVD morbidity and mortality in older women, a group characterized by severe, treatment-resistant hypertension and high risk for CVD events.