Children in the top 90th percentile for high BP had the greatest risk for CVD-related death.
Children with high blood pressure at age 7 years had greater risk for premature CV-related death in their mid-50s, according to results from a prospective study presented at the American Heart Association's Hypertension Scientific Sessions.
The association between hypertension and CVD-related mortality is recognized, but most children do not undergo routine BP screening, according to Alexa Freedman, PhD, assistant professor in the department of preventive medicine at Northwestern University Feinberg School of Medicine, and colleagues.
"Our results highlight the importance of screening for blood pressure in childhood and focusing on strategies to promote cardiovascular health beginning in childhood," Freedman told Healio.
To identify the association between childhood BP and risk for long-term CVD, Freedman and colleagues reviewed systolic and diastolic BP data from 38,252 children born between 1959 and 1965 who had their BP taken at age 7 years (50.7% male) as part of the Collaborative Perinatal Project (CPP) -- a study that analyzed the postnatal health of children from 40,000 mothers (49.4% Black) across 12 U.S. sites.
The researchers grouped each child's BP data into age, sex and height-specific percentiles based on American Academy of Pediatrics guidelines. They then conducted a survival analysis adjusted for other factors contributing to mortality, such as childhood BMI.
Mean systolic BP at age 7 was 102 mm Hg and mean diastolic BP was 61 mm Hg. Mean BMI at age 7 was 16 kg/m2. Twenty-one percent of children were classified as having hypertension, according to the researchers.
Overall, there were 2,837 deaths during a median follow-up of 54 years (interquartile range, 52-55); 504 deaths were tied to CVD mortality, according to the presentation.
According to the results, a 1 standard deviation higher systolic BP (HR = 1.15; 95% CI, 1.04-1.26) and diastolic BP (HR = 1.17; 95% CI, 1.07-1.29) was associated with increased risk for premature CVD-related death, according to the results, which were simultaneously published in JAMA.
Moreover, children with elevated BP at age 7, defined as the top 90th percentile, had a significantly higher risk for premature CVD-related death (adjusted HR = 1.48; 95% CI, 1.18-1.86). The same was observed for children with hypertension, defined as the top 95th percentile (aHR = 1.4; 95% CI, 1.12-1.76), according to data published in JAMA.
Next, researchers used a fixed-effects regression model on sibling clusters to determine whether a sibling with high BP had a higher risk of CVD mortality compared with their sibling with lower BP, accounting for shared familial and environmental factors. This analysis included 359 children in 150 sibling clusters.
Results showed the risk for premature CVD-related death was significantly higher for siblings with 1 standard deviation higher systolic BP (aHR = 1.14; 95% CI, 0.9-1.45) and diastolic BP (aHR = 1.18; 95% CI, 0.93-1.51), indicating a shared family environment may not be related to high BP, according to data published in JAMA.
Overall, the researchers concluded that the association between higher BP in childhood and premature CVD mortality in adulthood should prompt clinicians to routinely screen for BP.
In addition, Freedman said lifestyle interventions are important.
"Focusing on strategies to promote cardiovascular health beginning in childhood, including dietary changes and exercise, are key," Freedman said.
The researchers noted several study limitations, including having only one BP measurement and use of data from the 1960s and 1970s, which may not be generalizable to today's children, according to a related press release from the AHA.
"These findings raise questions about whether child blood pressure predicts cardiovascular mortality because it predicts higher blood pressure in adulthood," Freedman said. "Previous research has demonstrated that blood pressure trajectory from childhood to adulthood is important for CVD risk, which offers a good starting point."