Bone Abstracts

Objective: Insuficient vitamin D supply defined as serum hydroxyvitamin D (25OHD) <20 ng/ml is considered as one of possibile cardiovascular risk factors among adults with hypertension. Furthermore, some data also suggest an independent association between vitamin D deficits and hypertension and obesity during growth. The aim of the study was to assess vitamin D status in children and adolescents with hypertension.

Methods: The cross sectional study was performed on a group of 99 subjects (43 girls and 56 boys) aged 8.4–17.6 years (mean: 12.1), stratified according to their values of blood pressure (BP). Blood samples were taken to determine 25OHD; anthropometric traits and BP measurements were carried out using standard methods and equipment. The study was performed after winter time i.e. in March 2012.

Results: Only 8% of all studied children and adolescents demonstrated vitamin D level above 20 ng/ml, whereas predominantly severe deficits were found (92%). Significant correlations were observed between 25OHD and systolic BP (r=−0.37, P=0.0003) and mean BP (r=−0.3, P=0.002). Children and adolescents with normal systolic BP had better supply with vitamin D compared with age- and sex-matched hypertensive pairs i.e. subjects with critically increased systolic BP (>90th percentile). The association (P=0.03) was independent of age, BMI and anthropometric parameters.

Figure 1 Correlation between mean blood pressure (Mean BP) and serum concentration of 25(OH)D in subjects aged 8–17 years.

Conclusions: Our findings show associations between decreased levels of serum 25OHD and hypertension in adolescents suggesting potential role of vitamin D deficits in the development of this condition. However, these relationships and possible causal links need to be investigated in further prospective studies including larger groups of pediatric patients.