Association between obesity and elevated blood pressure in children and adolescents: A systematic review of clinical evidence

Background: The prevalence of overweight and obesity among children and adolescents continues to increase and represents a major modifiable cardiometabolic risk factor for elevated blood pressure. However, quantifying the magnitude of this risk remains challenging because pediatric blood-pressure diagnostic criteria vary, while an updated synthesis of longitudinal evidence is needed to evaluate the potential reversibility of adiposity-related hemodynamic abnormalities. Objective: This systematic review aimed to synthesize clinical evidence on the predictive association between pediatric obesity and the incidence of elevated blood pressure and hypertension, and to evaluate the effects of lifestyle modification on blood-pressure improvement in populations aged 2–18 years. Methods: Literature searches were conducted in PubMed and Google Scholar to identify English-language articles published between 2019 and 2024. Study selection followed the PECO framework and included prospective cohort studies and randomized clinical trials. Methodological quality was assessed using the Newcastle-Ottawa Scale (NOS) and Cochrane Risk of Bias 2 (RoB 2). Certainty of evidence was evaluated using the GRADE approach. Results: Six studies involving a total of 40,676 participants were included. Persistent pediatric overweight or obesity was consistently associated with a higher risk of incident hypertension during follow-up, with reported odds ratios (ORs) and hazard ratios (HRs) ranging from 2.26 to 8.5. Modification of the weight trajectory through reduction in obesity severity or lifestyle intervention was linearly associated with objectively measured improvements in blood pressure. Most of the included literature was judged to have a low risk of bias. Overall certainty of evidence was rated as Moderate. Conclusion: Childhood obesity is predictively associated with an increased incidence of hypertension that may persist into young adulthood. The evidence also indicates a clear potential for reversibility through lifestyle modification and reduction in obesity severity.