The Relationship Between White Blood Cell Counts and Pediatric Hypertension: A Prospective Cohort Study

Background: Childhood hypertension and prehypertension are critical public health issues. While adult hypertension risk factors are well-established, and different from childhood risk factors. Evidence linking white blood cell counts/subtypes to pediatric hypertension remains limited, with most studies focusing on adults or small pediatric samples. Methods: A prospective cohort study included 5,971 children aged 6-12 years in Chongqing, China was performed at baseline in 2014-2015 and 1,282 children received a 5-year follow-up in 2019. Measurements of white blood cell indicators including total white blood cell counts (WBC), lymphocyte counts and percentage (LC, LP), monocyte counts and percentage (MC, MP), neutrophil counts and percentage (ANC, NR), and lymphocyte-monocyte ratio (LMR) were detected by Complete Blood Count (CBC) tests. Blood pressure (BP), and anthropometrics indexes were also detected. Multilevel linear mixed and logistic regression models adjusted for confounders were applied to illustrate the relevance of cell counts indicators and blood pressure. Results: Elevated BP (EBP) group had significant lower MC(OR(95%CIs)=0.79(0.68,0.90)) and MP(OR(95%CIs)=0.78(0.68,0.88)) but higher LMR(OR(95%CIs)=1.31(1.15,1.50)) vs. normal BP group. Multi-variants analyses adjusted with confounding factors showed MP negatively correlated with SBP, DBP, MAP and LMR positively correlated(P<0.05). MC and MP reduced hypertension risk while LMR increased it, especially in boys. No significant mediation effect of WBC indices between BMI and BP was found. Conclusions: Peripheral MC, MP, and LMR were significantly associated with pediatric hypertension, with MC and MP as protective factors and LMR as a risk factor, suggesting them as potential biomarkers for childhood hypertension.