Associations of Physical Activity, Screen Time, and Adiposity with Elevated Blood Pressure in Preschool Children

Background/Objectives: Elevated screening blood pressure (BP) in preschool children is an important cardiovascular health concern. This cross-sectional study examined associations between objectively measured moderate-to-vigorous physical activity (MVPA), parent-reported screen time, adiposity indicators, and screening BP among children aged 5–6 years in Rzeszów, Poland. Methods: The study included 128 children attending public kindergartens. BP was assessed during a single screening session using an oscillometric device. Adiposity was evaluated using body mass index (BMI), bioelectrical impedance-derived body fat percentage (FAT), and waist-to-height ratio (WHtR). Physical activity was monitored using ActiGraph accelerometers for seven consecutive days, with valid accelerometry data available for 81 children. Screen time was parent-reported. Associations were examined using logistic regression and modified Poisson regression with robust variance estimation. Results: Screening SBP (systolic blood pressure) and/or DBP (diastolic blood pressure) ≥ 95th percentile was observed in 74 children (57.8%). FAT ≥ 85th percentile was significantly associated with elevated screening BP in adjusted logistic regression (aOR = 2.47; 95% CI: 1.09–5.59) and modified Poisson regression (aPR = 1.41; 95% CI: 1.04–1.92). BMI ≥ 85th percentile and WHtR ≥ 0.50 were not significantly associated with screening BP in the adjusted models. Weekend screen time > 1 h/day was associated with higher odds of elevated screening BP in adjusted logistic models, whereas no statistically significant association was observed for MVPA. Conclusions: BIA-derived body fat percentage was associated with elevated screening BP, but these findings do not establish its superiority over other adiposity indicators. The unusually high proportion of elevated BP values and the single-session screening assessment warrant caution. Larger prospective studies with repeated BP measurements are needed to confirm these associations.