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.