Introduction: Gender and race/ethnic disparities in the burden of adverse blood pressure (BP) levels in adulthood have origins in childhood. Proper timing of primordial prevention efforts could narrow inequalities in BP trajectories across the life course. Few studies have characterized the ages at which children transition from ideal BP by gender and race/ethnicity, using contemporary multiethnic populations.
Methods: We utilized the prevalence of ideal (<90th percentile for SBP and/or DBP), intermediate (90th-95th percentile or SBP ≥120 or DBP ≥80 mm Hg) and poor (>95th percentile for SBP and/or DBP) BP levels among African American (AA), European American (EA), and Mexican American (MA) NHANES participants (2007-2012, n=4,566) to estimate race/ethnic, age (8-19 years), and sex-specific net probabilities of transitioning between levels of BP using novel Markov-type modeling.
Results: At age 8, the prevalence of ideal BP differed more by gender than by race/ethnicity, with the prevalence of ideal BP among boys (AA: 87%; EA and MA: 89%) being lower than the prevalence of ideal BP in girls (AA: 92%, EA 94%, MA 96%). From age 8, the magnitude of net declines in ideal BP also varied by gender and race/ethnicity. For example, between ages 8-11, the population of AA boys with ideal BP declined a net 1.6% [95% confidence interval (CI): 1.3-1.8%] annually, net declines that were approximately 25% greater than net declines estimated in EA and MA boys. For all race/ethnic groups, annual net declines in ideal BP among girls were less than half the decline of their male counterparts. Between 12-15 years of age, the largest declines for both genders occurred in AAs (AA boys: 2.1%, 95% CI: 1.7-2.5%; AA girls: 0.9%, 95% CI: 0.7-1.1%). By age 19, the annual net declines in ideal BP increased to approximately 2.9% (95% CI: 2.3-3.5%) and 1.4% (95% CI: 1.1-1.7%) per year for AA boys and AA girls, respectively. These declines, together with earlier net transition patterns widened ideal BP disparities in both boys (AA 68%, EA 73%, MA 75%) and girls (AA 84%, EA 89% MA 93%) at age 19.
Conclusions: Disparities in transitions from ideal BP emerge during childhood and early adolescence, with disparate, rapid declines in ideal BP observed in boys and AAs, thus introducing BP disparities. Research emphasizing safe and effective primordial prevention efforts in childhood is necessary to preempt disparities and their maintenance.