Adiposity and Blood Pressure in Children and Adolescents: A National Cross-Sectional Study in China.

Background: Higher blood pressure (BP) in childhood is an important predictor of cardiovascular disease later in life, and adiposity is an important modifiable factor associated with BP. However, updated national evidence on the associations of general and central adiposity indicators with BP outcomes among Chinese children and adolescents remains limited. Methods: This cross-sectional study was based on physical health data collected from 146,399 children and adolescents across 30 provinces in China between October and November 2019. Height, weight, waist circumference, and BP were measured using standardized procedures, and adiposity was assessed using body mass index (BMI) and waist-to-height ratio (WHtR). Linear mixed-effects models were used to evaluate associations of BMI and WHtR with continuous BP outcomes, and generalized linear mixed-effects models were used for screening-defined hypertension (SDH), adjusting for sociodemographic, dietary, and physical activity variables. Results: Mean systolic BP and diastolic BP were 107.40 (SD 12.65) mmHg and 67.78 (SD 9.66) mmHg, respectively. After multivariable adjustment, each 1-unit increase in BMI was associated with increased odds of SDH (OR = 1.131, 95% CI: 1.123, 1.139), and each 0.1-unit increase in WHtR was associated with increased odds of SDH (OR = 1.798, 95% CI: 1.732, 1.866). Conclusions: Higher BMI and WHtR were associated with higher BP levels and greater odds of SDH among Chinese children and adolescents. These findings highlight the importance of early identification and prevention of adiposity-related BP abnormalities in youth.