Background: Vitamin D may have cardio-protective properties due to its biological actions. In children, observational studies linking actual vitamin D level and blood pressure have yielded conflicting results. Whether early life vitamin D exposure may elicit a programming effect on later systolic blood pressure (SBP) and diastolic blood pressure (DBP) needs further investigation.
Objective and hypotheses: We investigated whether higher levels of cord 25-hydroxyvitamin D (25OHD) correspond to lower SPB and DBP in 3 year-old children in the prospective, population-based birth cohort Odense Child Cohort (OCC).
Method: Of children included from OCC, we included singletons with data on cord 25OHD and blood pressure. SBP and DBP were measured using a Welch Allyn device with appropriate size cuffs. Multiple linear and logistic regression models were applied adjusted for maternal educational level, season of birth and child height, weight and age. All models were a priori stratified by sex. 25OHD was applied as a continuous variable and grouped by study-specific median levels.
Results: In 1110 children (530 girls, 580 boys) median (IQR) 25OHD was 46.3 (32.0;61.0) nmol/l; SPB 100.0 (95.0;105.0) mmHg; DBP 62.0 (59.0;66.0) mmHg. Adjusted analyses showed: In girls, SBP was 0.7 mmHg lower (P=0.001) and DBP was 0.4 mmHg lower (P=0.016) for every 10 nmol/l increase in cord 25OHD. Furthermore, girls with 25OHD levels >50 th percentile had 2.5 mmHg lower SBP (P=0.002) and 1.7 mmHg lower DBP (P=0.009) than the girls with levels <50p. Moreover, the odds of having a blood pressure >90p were reduced with higher cord 25OHD (SBP; OR 0.97 (0.950.99), P=0.004; 25OHD>50p vs<50p OR 0.36 (0.150.85), P=0.02, DBP; OR 0.98 (0.961.00), P=0.045). No associations were observed in boys.
Conclusion: SPB and DBP were significantly lower with higher levels of cord 25OHD in 3- year-old girls, but not in boys. This sex-specific pattern deserves further studies.
10 Sep 2016 - 12 Sep 2016