Association of serum 25-Hydroxyvitamin D with Vitamin D intervention and outdoor activity among children in North China: an observational study

Abstract

Background Living at high latitudes is one of the risk factors for vitamin D deficiency in children. However, evidence on vitamin D improvement for this pediatric population to date is limited. This study aims at evaluating the association of different vitamin D intervention methods and outdoor activity on the vitamin D status of children in North China. Methods In this observational study, a total of 55,925 children aged 1 month to 18 years old were recruited from pediatric outpatient departments from July 2016 to June 2017. Data on demographics, anthropometric measurements, vitamin D intervention (either prescribed by physicians or given by parents) and outdoor activity were recorded. The serum levels of 25-hydroxycholecalciferol (25(OH)D) were determined by high performance liquid chromatography tandem–mass spectrometry. Logistic regression analysis was performed to assess the association of vitamin D intervention or outdoor activity with blood vitamin D status, adjusted for age, gender, BMI for age, and seasons. Results The overall rate of hypovitaminosis D was 65.60%. Of the children’s outdoor activity, 35.63, 31.95, and 32.42% were below 30 min/d, 30–60 min/d and over 60 min/d, respectively. Furthermore, the proportion of therapeutic intervention, supplementation intervention and no vitamin D intervention among the children was 16.48, 32.87, and 50.65%, respectively. After adjusted for confounding factors, vitamin D intervention was associated with a lower risk of hypovitaminosis D, with OR (95% CI) of 0.191 (0.180, 0.202) in children with therapeutic doses and 0.423 (0.404, 0.443) in those with supplementation doses, compared with children without vitamin D intervention. In addition, longer outdoor time was associated with a lower risk of hypovitaminosis D [0.479 (0.456, 0.504) for 60 min/d, 0.737 (0.701, 0.776) for 30–60 min/d], independent of vitamin D intervention. Conclusions High prevalence of vitamin D deficiency was found in children living at high latitudes. Vitamin D intervention and outdoor activity are all negatively associated with children’s vitamin D deficiency. Routine vitamin D intervention combined with increased outdoor time might be an effective approach to prevent hypovitaminosis D among children, especially those at school, living at high latitudes.

Incidence of malnutrition and changes in phosphocalcic metabolism in perioperative liver transplantation patients -a retrospective study in a tertiary children’s hospital in China

“…In a retrospective study conducted by Xuguang Zhang et al, 55,925 children’s serum samples were collected to study the serum vitD levels. They found that the overall rate of hypovitaminosis D of 65.60% [ 25 ] was similar to our study results. We further analyzed the correlation between BMD and nutritional status.…”

Vitamin D Deficiency in Childhood Cancer Survivors: Results from Southern Thailand

“…Female gender, older age, obesity, limited dietary dairy intake, limited sun exposure, geographic region, and seasonal period have been reported as risk factors for vitamin D deficiency [ 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. Similarly, our study found that female gender, obesity, lack of outdoor activities, and lower dietary dairy intake were risk factors for vitamin D deficiency.…”

“…Previous studies that assessed the vitamin D status of healthy children in Thailand reported that the prevalence of vitamin D deficiency (25(OH)D < 20 ng/mL) was 19.5–33.4% [ 8 , 9 , 10 , 11 ]. Female gender, older age, obesity, limited dietary dairy intake, limited sun exposure, geographic region, and seasonal period have been reported as risk factors for vitamin D deficiency [ 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. In addition to these potential risks, CCSs have increased risks for vitamin D deficiency, including restrictions on outdoor activities and exposure to steroids, chemotherapy, and/or radiation.…”

Correlation analysis between vitamin A, D, and E status with altitude, seasonal variation, and other factors, among children aged 0–6 years in a Chinese population living in the Tibetan plateau of Ganzi prefecture

“…Therefore, it is very important to use supplements of Vit A, D, and E for these children, especially in the high‐altitude areas. 37 …”

“…The diet of children from this region is mainly composed of mantou, Zanba, buttered tea, highland barley, and yogurt, and they also occasionally eat beef and mutton but rarely vegetables, fruit, seafood, pork, or poultry. Therefore, it is very important to use supplements of Vit A, D, and E for these children, especially in the high‐altitude areas 37 …”