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Contemporary factors affecting serum 25-hydroxyvitamin D concentrations in Chinese children aged 2-6 years
Qian Chen1, Ting Yang1, Yongfang Liu2
1Department of Child Health Care, Children's Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Child Health and Nutrition, Chongqing400014, China.
Objective:
We investigated vitamin D (VitD) nutritional status in children aged 2-6 years to provide a basis for prevention and intervention strategies for VitD deficiency (VitDD) in Chinese children.
Design:
From November 2018 to September 2019, a total of 2192 healthy children aged 2-6 years were enrolled. The serum 25-hydroxyvitamin D (25(OH)D) concentrations were measured by liquid chromatography tandem MS.
Setting:
Twelve jurisdictions in eight provinces and cities across northern and southern China were selected through stratified cluster sampling.
Participants:
2192 children aged 2-6 years were enrolled.
Results:
(1) A serum 25(OH)D concentration of 23·87 (sd 8·24) ng/ml, a VitDS rate of 65·2 %, an insufficiency rate of 29·6 % and a deficiency rate of 5·2 % were noted. (2) Age (OR = 2·22, 95 % CI 1·86, 2·64) and spring (OR = 1·35, 95 % CI 0·91, 2·01) are risk factors for VitDD and VitDI. The male (OR = 0·68, 95 % CI 0·52, 0·90), the temperature (OR = 0·89, 95 % CI 0·86, 0·93), summer (OR = 0·25, 95 % CI 0·09, 0·68), autumn (OR = 0·26, 95 % CI 0·09, 0·74) the intake of VitD supplements (OR = 0·08, 95 % CI 0·03, 0·28), the intake frequency of dairy products (OR = 0·86, 95 % CI 0·78, 0·96) and egg products (OR = 0·83, 95 % CI 0·74, 0·93) are protective factors for VitDD and VitDI.
Conclusion:
VitDD in children aged 2-6 years is still prevalent in China, but the influencing factors of VitD nutrition have changed. Latitude is not the main factor in the 25(OH)D concentrations of children aged 2-6 years; temperature, intake of eggs and dairy products and sampling season have more obvious impacts.
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