The global rise in childhood and adolescent obesity represents one of the most serious public health challenges of the 21st century. According to the World Health Organization, the prevalence of overweight and obesity among children and adolescents aged 5–19 years has increased more than fourfold over the past four decades, with particularly rapid growth observed in low- and middle-income countries [1]. This epidemiological transition has been accompanied by the early emergence of cardiometabolic risk factors that were once considered diseases of adulthood, including hypertension, dyslipidaemia, insulin resistance, and subclinical vascular dysfunction [2,3]. Hypertension in adolescents is increasingly recognised as a critical intermediary between excess adiposity and future cardiovascular disease. Elevated blood pressure during adolescence is not a benign or transient finding; longitudinal studies demonstrate that adolescent hypertension tracks strongly into adulthood and is associated with early target-organ damage, such as left ventricular hypertrophy and increased carotid intima–media thickness [4,5]. Importantly, obesity is one of the strongest modifiable determinants of paediatric hypertension, with the prevalence of elevated blood pressure rising progressively from normal-weight to overweight and obese adolescents [6]. Despite these concerns, hypertension in adolescents frequently remains undiagnosed. The condition is typically asymptomatic, and routine blood pressure measurement is inconsistently performed in paediatric and school-health settings [7]. Moreover, diagnostic complexity related to age-, sex-, and height-specific blood pressure percentiles, as well as the requirement for repeated measurements on separate occasions, contributes to under-recognition in clinical practice [8]. As a result, a substantial proportion of adolescents—particularly those with overweight or obesity—harbour undetected hypertension that may persist for years before clinical recognition. Simple cuff-based blood pressure measurement remains the most accessible and scalable method for hypertension screening in adolescents. International guidelines, including those from the American Academy of Pediatrics, continue to endorse office-based blood pressure measurement as the first-line screening tool, especially in high-risk groups such as overweight and obese youth [9]. While ambulatory blood pressure monitoring improves diagnostic accuracy, its limited availability and higher cost restrict its routine use in large-scale or resource-limited screening programmes [10]. Consequently, understanding the burden of hypertension detected using simple blood pressure cuffs is essential for informing pragmatic screening strategies. Existing primary studies have reported highly variable prevalence estimates of hypertension among overweight and obese adolescents, ranging from single-digit percentages in large clinical cohorts to markedly higher figures in school-based surveys [11–13]. These discrepancies likely reflect differences in population characteristics, obesity severity, measurement protocols, and diagnostic criteria. To date, however, there is no comprehensive synthesis quantifying the prevalence of previously undiagnosed hypertension in overweight and obese adolescents identified through cuff-based blood pressure screening. Therefore, this systematic review and meta-analysis was undertaken to estimate the prevalence of undiagnosed hypertension among overweight and obese adolescents using simple blood pressure cuff measurements and to explore sources of heterogeneity across studies. By consolidating available evidence, this review aims to inform clinicians, school health programmes, and policymakers about the magnitude of hidden hypertension risk in this vulnerable population and the potential value of targeted blood pressure screening.

Study design and reporting standards This study was conducted as a systematic review and meta-analysis in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines [14]. A predefined methodology was followed to identify, appraise, and synthesize evidence on the prevalence of undiagnosed hypertension among overweight and obese adolescents detected using cuff-based blood pressure measurement. Eligibility criteria Studies were selected based on the PICOS framework: • Population: Adolescents aged approximately 10–19 years. Studies including broader age ranges were eligible if adolescent-specific data were extractable. • Exposure: Overweight and/or obesity defined using standard BMI-based criteria (WHO, CDC, IOTF, or study-specific validated cut-offs). • Outcome: Prevalence of hypertension or elevated blood pressure, detected using office- or screening-based blood pressure measurement with a simple cuff. • Study design: Observational studies (cross-sectional surveys, school-based screening studies, cohort studies, or health-system–based analyses). • Setting: Community, school, or clinical settings. Exclusion criteria included: • Studies reporting only mean blood pressure without prevalence data • Studies focusing exclusively on adults or children below adolescence • Studies using ambulatory blood pressure monitoring alone without office BP screening data • Case reports, reviews, editorials, and conference abstracts without full data Information sources and search strategy A comprehensive literature search was conducted in PubMed/MEDLINE, Scopus, Embase, and Google Scholar from database inception to June 2025. The search strategy combined controlled vocabulary and free-text terms related to adolescents, obesity, hypertension, and blood pressure screening. Key search terms included: adolescent, overweight, obesity, hypertension, elevated blood pressure, screening, undiagnosed, and prevalence. Reference lists of eligible studies and relevant reviews were also manually screened to identify additional studies [15]. Study selection All retrieved records were imported into a reference manager, and duplicates were removed. Two reviewers independently screened titles and abstracts for relevance. Full-text articles were subsequently assessed against the eligibility criteria. Discrepancies were resolved through discussion and consensus. The study selection process was documented using a PRISMA 2020 flow diagram [14]. Data extraction Data were independently extracted by two reviewers using a standardized extraction form. Extracted variables included: • Author and year of publication • Country and study setting • Study design and sample size • Age range and sex distribution • BMI classification criteria • Blood pressure measurement method (device type, number of readings, number of visits) • Diagnostic criteria for hypertension • Prevalence of hypertension in overweight and obese adolescents (numerator and denominator) Where necessary, corresponding authors were contacted for clarification or missing data. Risk of bias assessment The methodological quality of included studies was assessed using the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for Studies Reporting Prevalence Data [16]. This tool evaluates sampling methods, measurement validity, statistical analysis, and response rates. Studies were categorized as having low, moderate, or high risk of bias based on overall appraisal. Data synthesis and statistical analysis Prevalence estimates of hypertension were extracted separately for overweight and obese adolescents. When appropriate, pooled prevalence estimates were calculated using a random-effects meta-analysis (DerSimonian–Laird method) to account for between-study variability [17]. Prevalence data were transformed using the Freeman–Tukey double arcsine method to stabilize variances. Statistical heterogeneity was assessed using the I² statistic, with values of 25%, 50%, and 75% representing low, moderate, and high heterogeneity, respectively [18]. Given the anticipated clinical and methodological heterogeneity, subgroup analyses were planned based on: • Study setting (school-based vs clinical) • Geographic region • Hypertension diagnostic criteria Publication bias was not formally assessed due to the limited number of included studies, in line with methodological recommendations [19]. All analyses were planned using standard meta-analysis software.

Figure 2. Relationship between body mass index category and prevalence of cuff-detected hypertension among adolescents. Both included studies demonstrate a clear positive gradient, with higher prevalence observed in obese adolescents compared with overweight adolescents. Meta-analysis and heterogeneity Although a random-effects meta-analysis was planned, the small number of included studies and marked variability in prevalence estimates resulted in extreme statistical heterogeneity (I² >90%) for both overweight and obese groups. Consequently, pooled prevalence estimates were considered unreliable and are not emphasized. Instead, results are presented descriptively, highlighting the wide range of hypertension prevalence detected using simple cuff-based screening across different settings. Key findings • Undiagnosed hypertension was identified in a substantial proportion of overweight and obese adolescents using simple BP cuff measurements. • Prevalence estimates varied widely between clinical and school-based settings. • Obese adolescents consistently showed a higher burden of hypertension compared with overweight adolescents. • Extreme heterogeneity limited the interpretability of pooled estimates, underscoring the need for standardized screening and reporting methodologies. Figure 3. Study-specific prevalence estimates of undiagnosed hypertension among overweight and obese adolescents identified using simple cuff-based blood pressure measurement. A pooled estimate is not presented due to extreme heterogeneity (I² >90%) and limited number of studies.

This systematic review and meta-analysis highlights a substantial but highly variable burden of undiagnosed hypertension among overweight and obese adolescents, detected using simple cuff-based blood pressure measurements. Across included studies, hypertension prevalence ranged from 2.0–34.0% in overweight and 5.6–46.7% in obese adolescents, with a consistent positive gradient across BMI categories. Although heterogeneity precluded reliable pooling, the directionality and magnitude of effect underscore obesity as a dominant driver of early blood pressure elevation in youth. Biological and pathophysiological mechanisms The association between excess adiposity and elevated blood pressure in adolescents is biologically plausible and multifactorial. Adipose tissue acts as an endocrine organ, promoting sympathetic nervous system activation, renin–angiotensin–aldosterone system (RAAS) upregulation, and sodium retention, all of which increase vascular tone and intravascular volume [20–22]. Obesity-related insulin resistance further augments renal sodium reabsorption and sympathetic activity, compounding BP elevation [23]. In parallel, adipokine imbalance (elevated leptin, reduced adiponectin) and low-grade systemic inflammation contribute to endothelial dysfunction and arterial stiffness, changes that have been demonstrated even in adolescents [24,25]. These mechanisms provide a coherent explanation for the stepwise rise in hypertension prevalence from overweight to obesity observed across studies. Measurement context and heterogeneity The wide variability in prevalence estimates likely reflects methodological and contextual differences rather than true biological inconsistency. School-based surveys may capture transient elevations related to anxiety, activity, or single-visit measurements, whereas large health-system cohorts often incorporate repeated measurements over time, yielding lower point prevalence [26,27]. Pediatric BP measurement is particularly sensitive to cuff size, positioning, rest period, and number of readings, and failure to adhere to standardized protocols can overestimate hypertension [28]. Moreover, diagnostic criteria have evolved, with newer guidelines adopting lower thresholds for adolescents ≥13 years, potentially inflating prevalence relative to older definitions [29]. Clinical and public health implications Despite policy uncertainty regarding universal screening benefits in asymptomatic youth, these findings support targeted BP screening among adolescents with overweight or obesity, a group at substantially higher risk [30]. Simple cuff-based measurement is inexpensive and scalable, making it suitable for school health programs and primary care as a first-line screen. However, to minimize misclassification, elevated readings should prompt repeat measurements across separate visits, with confirmation using ABPM or home BP monitoring when feasible, in line with contemporary pediatric guidelines [29,31]. Early identification is clinically meaningful, as lifestyle interventions—weight reduction, dietary sodium restriction, and physical activity—have demonstrated efficacy in lowering BP in adolescents [32,33]. Comparison with existing literature Our findings align with prior narrative reviews and cohort studies demonstrating a strong BMI–BP relationship in youth, but add specificity by focusing on undiagnosed hypertension detected via cuff-based screening [34,35]. The markedly higher prevalence reported in some school-based studies echoes observations from low- and middle-income settings, where rapid nutrition transition and limited routine screening may amplify hidden disease burden [36]. Conversely, lower prevalence in large clinical cohorts may reflect more conservative confirmation practices and broader population denominators [27]. Strengths and limitations Key strengths include a PRISMA-aligned methodology, strict inclusion criteria requiring BMI-stratified prevalence, and a focus on pragmatic screening methods relevant to real-world practice. Limitations are notable: the small number of eligible studies, extreme heterogeneity, and inconsistent confirmation protocols limit generalizability and preclude pooled estimates. Additionally, reliance on office/screening BP without uniform multi-visit confirmation may overestimate true sustained hypertension in some settings. Future directions Future studies should adopt standardized BP measurement protocols, report multi-visit confirmed hypertension, and provide granular BMI stratification (including obesity severity). Large, multicenter school-based studies with protocolized confirmation pathways would be particularly valuable to inform policy and programmatic decisions. In summary, cuff-based BP screening reveals a meaningful prevalence of previously unrecognized hypertension among adolescents with overweight and obesity, with risk increasing alongside BMI. While prevalence estimates vary widely, the consistent BMI–hypertension gradient supports targeted screening coupled with standardized confirmation to enable early intervention and long-term cardiovascular risk reduction.

Undiagnosed hypertension is common among overweight and obese adolescents and increases progressively with rising body mass index. Simple cuff-based blood pressure measurement can identify a substantial proportion of at-risk individuals, although prevalence estimates vary widely across settings. These findings support targeted blood pressure screening in adolescents with excess weight, coupled with standardized measurement and confirmation strategies, to enable early intervention and reduce future cardiovascular risk.

1. World Health Organization. Obesity and overweight. Geneva: WHO; 2023. 2. Reilly JJ, Kelly J. Long-term impact of overweight and obesity in childhood and adolescence on morbidity and premature mortality in adulthood: systematic review. Int J Obes (Lond). 2011;35:891–898. 3. Freedman DS, Mei Z, Srinivasan SR, Berenson GS, Dietz WH. Cardiovascular risk factors and excess adiposity among overweight children and adolescents: the Bogalusa Heart Study. J Pediatr. 2007;150:12–17. 4. Chen X, Wang Y. Tracking of blood pressure from childhood to adulthood: a systematic review and meta-regression analysis. Circulation. 2008;117:3171–3180. 5. Litwin M, Niemirska A. Intima–media thickness measurements in children with cardiovascular risk factors. Pediatr Nephrol. 2009;24:707–719. 6. Sorof JM, Daniels SR. Obesity hypertension in children: a problem of epidemic proportions. Hypertension. 2002;40:441–447. 7. Falkner B, Lurbe E. Primary hypertension beginning in childhood and risk for future cardiovascular disease. J Pediatr. 2009;155:S7–S13. 8. Chiolero A, Cachat F, Burnier M, Paccaud F, Bovet P. Prevalence of hypertension in children: a systematic review. J Hypertens. 2007;25:1201–1213. 9. Flynn JT, Kaelber DC, Baker-Smith CM, et al. Clinical practice guideline for screening and management of high blood pressure in children and adolescents. Pediatrics. 2017;140:e20171904. 10. Wühl E, Witte K, Soergel M, Mehls O, Schaefer F. Distribution of 24-hour ambulatory blood pressure in children: normalized reference values. Circulation. 2002;106:181–187. 11. Koebnick C, Mohan YD, Li X, et al. High blood pressure in overweight and obese youth: implications for screening. J Clin Hypertens (Greenwich). 2013;15:793–805. 12. Gupta N, Goel K, Shah P, Misra A. Childhood obesity in developing countries: epidemiology, determinants, and prevention. Indian J Pediatr. 2012;79:127–133. 13. Singh M, Kumar R, Joshi S. Study of obesity and hypertension in school-going children aged 10–16 years. J Contemp Clin Pract. 2025;5:45–50. 14. Page MJ, McKenzie JE, Bossuyt PM, et al. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ. 2021;372:n71. 15. Liberati A, Altman DG, Tetzlaff J, et al. The PRISMA statement for reporting systematic reviews and meta-analyses. PLoS Med. 2009;6:e1000097. 16. Joanna Briggs Institute. Critical Appraisal Checklist for Studies Reporting Prevalence Data. Adelaide: JBI; 2020. 17. DerSimonian R, Laird N. Meta-analysis in clinical trials. Control Clin Trials. 1986;7:177–188. 18. Higgins JPT, Thompson SG, Deeks JJ, Altman DG. Measuring inconsistency in meta-analyses. BMJ. 2003;327:557–560. 19. Sterne JAC, Sutton AJ, Ioannidis JPA, et al. Recommendations for examining and interpreting funnel plot asymmetry in meta-analyses. BMJ. 2011;343:d4002. 20. Hall JE, do Carmo JM, da Silva AA, Wang Z, Hall ME. Obesity-induced hypertension: interaction of neurohumoral and renal mechanisms. Circ Res. 2015;116:991–1006. 21. Rahmouni K, Correia MLG, Haynes WG, Mark AL. Obesity-associated hypertension: new insights into mechanisms. Hypertension. 2005;45:9–14. 22. Grassi G, Seravalle G, Dell’Oro R, et al. Sympathetic activation in obese normotensive subjects. Hypertension. 2004;43:537–542. 23. DeFronzo RA. Insulin resistance, lipotoxicity, type 2 diabetes and atherosclerosis. Diabetologia. 2010;53:1270–1287. 24. Urbina EM, Khoury PR, McCoy CE, et al. Cardiac and vascular consequences of prehypertension in youth. J Clin Hypertens. 2011;13:332–342. 25. Pickering TG, Hall JE, Appel LJ, et al. Recommendations for blood pressure measurement in humans and experimental animals. Hypertension. 2005;45:142–161. 26. US Preventive Services Task Force. Screening for high blood pressure in children and adolescents: US Preventive Services Task Force recommendation statement. JAMA. 2020;324:1878–1883. 27. Kelley GA, Kelley KS. Effects of aerobic exercise on blood pressure in children and adolescents: a meta-analysis. Prev Cardiol. 2003;6:8–16. 28. Ho M, Garnett SP, Baur LA, et al. Effectiveness of lifestyle interventions in child obesity: systematic review with meta-analysis. Pediatrics. 2012;130:e1647–e1671.