PHOENIX — , new observational data suggest. The Black Women’s Health Study, which has followed 59,000 participants in the United States since 1990s, also showed that those who develop hypertension before age 45 have twice the risk of suffering a stroke.
“The really concerning thing about this data is the high proportion of young Black women who had high blood pressure and are suffering strokes relatively early in life,” said the study’s lead author, Hugo J. Aparicio, MD, associate professor of neurology at Boston University Chobanian & Avedisian School of Medicine, Boston. “This can lead to a burden of disability in relatively young women who may be at the prime of their life, pursuing careers, and looking after family.”
Dr. Aparicio presented the data at the International Stroke Conference presented by the American Stroke Association, a division of the American Heart Association.
He explained that while there has been good progress in reducing stroke rates in older people over the past decades, there is a concerning observation from multiple datasets showing that stroke rates in midlife have been plateauing or even increasing in recent years.
“For Black women specifically, there is a concern, as we know this group has higher rates of raised blood pressure and stroke overall,” said Dr. Aparicio. “We were interested in looking at whether the onset of hypertension at an earlier age in this group is one of the reasons for the increased stroke risk in midlife.”
A Large Study Cohort
The researchers analyzed data from the Black Women’s Health Study; the baseline year for this analysis, which included 46,754 stroke-free participants younger than age 65 (mean age, 42 years), was the 1999 questionnaire.
Both history of hypertension — defined as physician-diagnosed hypertension with the use of an antihypertensive medication — and stroke occurrence were determined by self-report. It has been shown in previous studies that these self-reported data on incidence of hypertension in this dataset are highly reliable, Dr. Aparicio noted.
At baseline, 10.5% of participants aged 45-64 years had hypertension. Stroke occurred in 3.2% of individuals over a mean follow-up of 17 years.
Black women with hypertension before age 45 had a higher risk for midlife stroke (hazard ratio [HR], 2.23; 95% confidence interval [CI], 1.79-2.78), after adjustment for age, neighborhood socioeconomic status, residence in the Stroke Belt, smoking, body mass index, and diabetes than women with no history of hypertension.
The risk was also increased with hypertension at midlife ages 45-64 years (HR, 1.69; 95% CI, 1.47-1.95) and was highest among those with hypertension at ages 24-34 years (HR, 3.15; 95% CI, 1.92-5.16).
“Our results show that among young Black women, those with hypertension have a much higher stroke risk than those without hypertension, even if they are taking antihypertensive medication,” Dr. Aparicio said. “This underscores how potent hypertension is as a risk factor for stroke.”
He concluded that both individuals and doctors need to realize that hypertension and stroke are not problems of the elderly exclusively.
“These are conditions that need to be addressed very early in life. This is even more important for Black women, as they are a high-risk group. They need to pay attention to blood pressure numbers early in life — ideally from adolescence — to catch levels before they become too elevated,” Dr. Aparicio said.
“We also need to address lifestyle changes including diet, physical activity, sleep habits, and address other cardiovascular risk factors such as cholesterol and body mass index, so we can prevent strokes from occurring,” he added. “At the policy level, we need to advocate, provide and fund primary prevention measures, and enable earlier screening and better treatment.”