Looking for new diagnostic tools and biomarkers of hypertension in obese pediatric patients

Introduction Development of obesity in childhood may be linked to an increased risk of hypertension. Objectives This study aimed (a) to analyze the expression of genes associated with blood pressure (BP) in obese children, (b) to evaluate ambulatory blood pressure monitoring (ABPM) as a diagnostic tool in hypertension in children, and (c) to assess the prevalence of metabolic syndrome in children with obesity. Patients and methods Office BP measurements and ABPM were performed in 49 children with obesity and 25 age-matched healthy children. Expressions of 12 monogenic hypertension genes and 45 genes variants associated with BP were assessed using the microarray technique. Results No significant differences in gene expression levels were found. Children with obesity had significantly higher (P<0.001) mean office systolic and diastolic BPs compared with the controls. The diagnosis of high normal BP and hypertension with ABPM was established in 27 and 33% of children, respectively. Nocturnal BP decrease less than 10% was found in 27% of children, whereas nocturnal BP decrease more than 20% was found in 13% of children. Nocturnal BP increase was found in 13% of patients. The diagnosis of metabolic syndrome was established in 29% of obese patients. Conclusion The following can be concluded: (a) the prevalence of metabolic syndrome was found in nearly one-third of children with obesity. (b) ABPM is a useful and reliable tool in the diagnostics of pediatric hypertension. Abnormal BP can be observed in ∼50% of obese children. (c) The lack of significant differences in gene expression levels is consistent with the concept of ‘missing heritability’ in pediatric hypertension.