Analysis of vitamin D status among children under 7 years of age in some regions of China / 中华儿科杂志

Objective: To explore current vitamin D status and influential factors of vitamin D deficiency and insufficiency among children under 7 years of age in 11 provinces, autonomous regions or municipalities of China. Methods: According to the "province-city-hospital" sampling technical route, a total of 1 531 healthy children under 7 years of age were sampled from 11 provinces, autonomous regions or municipalities in China by the cluster random sampling method from November 2020 to November 2021. The demographic information, family conditions, behavior and living habits and feeding behaviors were collected using unified questionnaire. Serum 25-hydroxyvitamin D(25(OH)D) levels were measured by liquid chromatography-tandem mass spectrometry. Serum 25(OH)D<30 nmol/L was considered deficient and 30-50 nmol/L was considered insufficient. With 25(OH)D≤50 nmol/L as the dependent variable, multivariate Logistic regression was applied to analyze the association between vitamin D deficiency and insufficiency and potential influential factors. Results: The prevalence of vitamin D deficiency and insufficiency among children under 7 years of age in 11 provinces, autonomous regions or municipalities of China was 14.0% (215/1 531), 3.8% (25/664) and 21.9% (190/867) in 0-<3 and 3-<7 of age years, respectively. Compared to children aged 0-<3 years, children aged 3-<7 years had a 2.6-fold increased risk of vitamin D deficiency and insufficiency (OR=3.60, 95%CI 1.93-6.72, P<0.001). Frequent sunlight exposure (OR=0.46, 95%CI 0.29-0.73, P=0.001), vitamin D supplementation (sometimes, OR=0.33, 95%CI 0.21-0.51, P<0.001; daily, OR=0.20, 95%CI 0.11-0.36, P<0.001) and infant formula intake(4-7 times per weeks, OR=0.43, 95%CI 0.28-0.68, P<0.001) were protective factors for vitamin D deficiency and insufficiency. Conclusion: Vitamin D deficiency and insufficiency are common among children under 7 years of age in 11 provinces, autonomous regions or municipalities of China, which is affected by age, sunlight exposure, vitamin D supplementation and infant formula intake.

Dilated cardiomyopathy and sudden death associated with vitamin D and calcium / 中国实用儿科杂志

Hypocalcemic cardiomyopathy could result in sudden congestive heart failure,cardiogenic shock,or sudden death. One of the causes of congestive heart failure is hypocalcemic cardiomyopathy. Beware of hypocalcemic cardiomyopathy at the diagnosis of dilated cardiomyopathy during infancy.Hypocalcemia is a biochemical characteristic,and cardiomyopathy is pathological feature in hypocalcemia cardiomyopathy.Vitamin D deficiency is the primary cause of cardiomyopathy.Hypocalcemia cardiomyopathy is based on vitamin D or calcium deficiency. Hypocalcemic cardiomyopathy responds well to vitamin D and calcium supplementation.