Vitamin D Deficiency in Children With Vasovagal Syncope Is Associated With Impaired Circadian Rhythm of Blood Pressure

Abstract

BackgroundVitamin D deficiency is associated with the risk of cardiovascular diseases. We aimed to investigate the serum vitamin D levels in children with vasovagal syncope (VVS) and explore the correlation of vitamin D status and circadian rhythm of blood pressure in VVS pediatric patients.MethodsThis was a retrospective study. 130 syncopal children diagnosed with VVS were included in the study. 110 age and gender matched healthy individuals were enrolled as control. According to serum 25(OH)D levels, VVS patients were divided into vitamin D sufficient group and vitamin D deficient group. Detailed information of VVS children with vitamin D deficiency and sufficiency on demographic data, baseline laboratory testing, echocardiogram, ambulatory blood pressure monitoring, and Holter ECG recording were extracted and analyzed.ResultsVVS children had a higher prevalence of vitamin D deficiency compared with healthy individuals (33.8% vs. 20.0%, P = 0.017). VVS patients with vitamin D deficiency had a higher rate of non-dipper blood pressure (79.5% vs. 59.3%, P = 0.021) and a lower value of square root of mean squared differences of successive normal to normal intervals (rMSSD) (median 107.8 vs. 141.0 ms, P = 0.035) compared with those with vitamin D sufficiency. Logistic regression analysis showed that non-dipper blood pressure was associated with serum 25(OH)D level [OR = 0.979, 95% CI (0.960, 0.999), P = 0.036].ConclusionVVS pediatric patients had a higher prevalence of vitamin D deficiency. VVS children with vitamin D deficiency showed a higher rate of non-dipper blood pressure, suggesting that vitamin D deficiency is correlated with impaired circadian rhythm of blood pressure.

Serum Vitamin D Levels in Children and Adolescents with Vasovagal Syncope, Syncope Due to Orthostatic Hypotension, and Cardiac Syncope

“…This study indicates that vitamin D deficiency was common among children and adolescents with syncope and demonstrates a prevalence of 60.0% in the VVS group, 54.2% in the group of syncope due to OH, and 47.4% in the group of CS which are not statistically different. These results are partially comparable with other studies of 25(OH)D levels in children with VVS which showed that 33.8% had vitamin D deficiency 19 and 60.0% 14 and suggested that 25(OH)D may be involved in the pathological mechanism of different syncope types by affecting cardiac autonomic function.…”

“…Some recent studies have shown that VVS in children is associated with reasonably low vitamin D levels. 14 , 19 Gialini et al 20 reported an association between probability of OH and circulating vitamin D levels in elderly males. Despite this fact, Laird et al 21 published another study results in which the authors described that vitamin D concentration was not significantly associated with OH in older adults.…”

“…Zhang et al 14 determined a positive correlation between vitamin D levels and rMSDD values, suggesting that pediatric patients with VVS may have decreased parasympathetic nervous tone as a result of vitamin D deficiency. Zou et al 19 reported that rMSDD parameter was decreased in children with VVS and vitamin D deficiency compared to children with sufficient 25(OH)D status. Although our results showed that HRV parameters did not correlate with serum 25(OH)D level in VVS group and syncope due to OH group, positive correlations between vitamin D concentration and pNN50, TP, and LF parameters of HRV in CS group of patients were detected.…”

Association between vitamin D deficiency and vasovagal syncope: A systematic review and meta‐analysis

“…Moreover, Egger's and Begg's 22,23 Duplicates were removed (n = 89) and the remaining 365 went through the first screening using titles/abstracts after which 25 studies underwent full-text screening. Finally, six studies 14,15,[24][25][26][27] remained to be included in our systematic review.…”

“…There was a total of 954 individuals assessed in these studies. Four studies were conducted in China 15,24,26,27 and the design of all but one of them 24 was a retrospective cohort.…”