Predictors of high blood pressure in children from 6 to 11 years: The PREDI cohort study

Abstract Background Hypertension is an important cardiovascular disease (CVD) in Brazil that affects approximately 30% of the adult population and accounts for nearly 50% of CVD-related deaths in the country. Identifying the main predictors of high blood pressure (BP) during childhood will help prevent the development of other CVDs in adulthood and deaths. This study aimed to estimate the effect of biological, demographic, and socioeconomic characteristics on the child’s BP at 6, 9 and 11 years of age. Methods Cohort study conducted with 181 children in Joinville city, southeastern Brazil. Individual data were collected during three follow-ups (2016, 2021, and 2023) in a private room of the family’s home. BP was measured by the auscultatory method. Poisson regression analysis adjusted for important covariates was used to estimate the relative risk (RR) of maternal and child weight status, demographic, and socioeconomic characteristics on the child’s BP at ages 6, 9 and 11. Results The prevalence of high BP in children at ages 6, 9 and 11 was 26.5%, 20.4% and 3.0%, respectively. Pre-pregnancy body mass index (BMI) and the child’s BMI were associated with high BP over the period investigated. The risk of children having high diastolic BP from 6 to 11 years of age was 6% higher (RR = 1.06; 95%CI 1.01, 1.11) when mothers had pre-pregnancy BMI ≥25 kg/m2, even after adjusting for child BMI. For each one kg/m2 increase in child BMI, the risk of children having high systolic BP pressure increased by 14% (RR = 1.14; 95%CI 1.05, 1.23), even after adjusting for pre-pregnancy BMI. Conclusions Pre-pregnancy excess body weight and increased child BMI were associated with high BP in children from 6 to 11 years of age. Addressing pre-pregnancy excess body weight and overweight in childhood, combined with BP monitoring from the age of six, are actions that can prevent the development of CVDs in adulthood, thus reducing a serious global public health problem. Key messages • Encouraging parents to monitor their children’s BP is essential to prevent associated chronic diseases throughout life. • Identifying children with altered blood pressure is an important public health indicator.