Prevalence and Determinants of Vitamin D Deficiency in 9595 Mongolian Schoolchildren: A Cross-Sectional Study.

Jorick Bater,Enkhjargal Tsendjav,Yanjmaa Jutmann,Davaasambuu Ganmaa,Tuyatsetseg Jambal,Adrian R Martineau,Enkhsaikhan Lkhagvasuren,Sabri Bromage

doi:10.3390/nu13114175

Abstract

Population-based data relating to vitamin D status of children in Northeast Asia are lacking. We conducted a cross-sectional study to determine the prevalence and determinants of vitamin D deficiency in 9595 schoolchildren aged 6–13 years in Ulaanbaatar (UB), the capital city of Mongolia. Risk factors for vitamin D deficiency were collected by questionnaire, and serum 25-hydroxyvitamin D (25[OH]D) concentrations were measured using an enzyme-linked fluorescent assay, standardized and categorized as deficient (25[OH]D <10 ng/mL) or not. Odds ratios for associations between independent variables and risk of vitamin D deficiency were calculated using multivariate analysis with adjustment for potential confounders. The prevalence of vitamins D deficiency was 40.6% (95% CI 39.7% to 41.6%). It was independently associated with female gender (adjusted odds ratio [aOR] for girls vs. boys 1.23, 95% CI 1.11–1.35), month of sampling (aORs for December–February vs. June–November 5.28 [4.53–6.15], March–May vs. June–November 14.85 [12.46–17.74]), lower levels of parental education (P for trend <0.001), lower frequency of egg consumption (P for trend <0.001), active tuberculosis (aOR 1.40 [1.03–1.94]), household smoking (aOR 1.13 [1.02 to1.25]), and shorter time outdoors (P for trend <0.001). We report a very high prevalence of vitamin D deficiency among Mongolian schoolchildren, which requires addressing as a public health priority.

Highlights

It is estimated that at least 1 billion individuals globally have sub-optimal serum25-hydroxyvitamin D [25(OH)D] levels [1]
Using data from the parent vitamin D supplementation trial, we identified several predictors that were associated with vitamin D deficiency, including gender, months sampled, district of residency, parental education, frequency of egg consumption, TB status, any smoking in the household, and frequency of daily outdoor activity
Higher frequency of egg consumption was associated with lower odds of vitamin D deficiency, which has been corroborated as a good source of vitamin D in the Asian region [18] due to a limited number of foods naturally containing vitamin D being produced in this area of the world [19]

Summary

Introduction

It is estimated that at least 1 billion individuals globally have sub-optimal serum25-hydroxyvitamin D [25(OH)D] levels [1]. Mongols have low 25(OH)D levels, due in part to Mongolia’s high latitude, increasing amounts of air pollution, especially in the capital city of Ulaanbaatar, lack of sun exposure during winter and spring, and lack of access to vitamin D-rich food (e.g., fish and mushrooms) [5,6,7]. To address these issues, the Mongolian government has been considering solutions for the problem of vitamin D deficiency and ways that might promote the supply of micronutrients (like vitamin D) to the general population. Fortification can be a strong tool for alleviating micronutrient deficiency, other risk factors within the Mongolian population may have major links to vitamin D deficiency in Mongolia

Methods

Results

Discussion

Conclusion