April 02, 2021
2 min read
New findings published in Hypertension highlight the need for prevention strategies to reduce BP levels due to the nearly fourfold incidence of stroke observed among Black young adults.
“We do not fully understand the underlying reasons for this risk gap, but there are likely to be a number of contributing factors,” Stephen Sidney, MD, MPH, research scientist at the division of research at Kaiser Permanente Northern California, told Healio. “Studies have shown that stroke incidence and hospitalization rates have increased among young adults in recent decades. Studies have also repeatedly shown that compared with white adults, Black adults tend to have an earlier age of onset, a longer duration and a greater severity of hypertension. Our study shows the impact of this disparity.”
The researchers analyzed 5,079 young and middle-aged participants from the CARDIA cohort (mean age, 30 years; 55% women) who had BP measured during nine examinations from 1985 to 2016. Participants were classified as having normal BP, elevated BP, stage 1 hypertension or stage 2 hypertension. Baseline BP categories were obtained using the highest BP from the third examination and time-dependent categories were obtained using follow-up measurements.
During the mean follow-up of 26.1 years, fatal/nonfatal stroke occurred among 100 participants, with 65 defined as ischemic stroke. Overall stroke incidence per 100,000 person-years was 76, similar between men and women (71 vs. 79, respectively; P = .61) but higher among Black participants compared with white participants (120 vs. 29; P < .001).
Researchers observed an association between stage 2 hypertension and increased risk for stroke at baseline (HR = 3.72; 95% CI, 2.12-6.54), as a time-dependent variable (HR = 5.84; 95% CI, 3.43-9.95), at age 30 years (HR = 4.14; 95% CI, 2.19-7.82) and at age 40 years (HR = 5.59; 95% CI, 3.35-9.31). Elevated BP and stage 1 hypertension were linked to nonsignificant increases in risk for stroke.
In a multivariate-adjusted model, the relationship between systolic BP and stroke incidence (HR per 1 standard deviation increase = 1.84; 95% CI, 1.46-2.31) was stronger than that between diastolic BP and stroke incidence (HR per 1 standard deviation increase = 1.58; 95% CI, 1.25-1.99). The association between systolic BP and stroke began at 90 mm Hg, Sidney and colleagues wrote.
According to Sidney, the study confirms the importance of high BP, how long an individual has high BP and how long damage to the blood vessels has occurred.
“It’s not enough to identify high blood pressure and treat it,” Sidney told Healio. “We need to address the reasons why people are getting high blood pressure in the first place.”
The bottom line, Sidney said in an interview, is “we need to provide better education to teens, young adults and older adults about how to prevent high blood pressure and other risk factors that increase risk for heart disease. We also need to implement policies that will reduce and lead to the elimination of the economic and racial disparities that are a major driver of inequities in health.”
For more information:
Stephen Sidney, MD, MPH, can be reached at [email protected]