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Vitamin D deficiency in children with severe disabilities under limited ultraviolet exposure
Yota Sato1, Atsushi Kamei2, Hiroyuki Toda3
1Iwate Prefectural Rehabilitation and Nursery Center for Disabled Children, 2-1-3 Idai-dori Yahaba-cho, Shiwa-gun, Iwate, 028-3603, Japan. y-sato@i-ryouiku.jp.
Introduction:
Nutritional prevention of osteoporosis management is an important issue for children with severe disabilities. Due to the coronavirus disease 2019 (COVID-19) pandemic that started in 2020, children admitted to institutions had fewer opportunities for ultraviolet (UV) exposure owing to restrictions on attending school and going out. Hence, the vitamin D (VD) status of these children has been a cause of concern. This study aimed to assess the correlation between VD intake and VD status among children with severe disabilities who had limited UV exposure.
Materials And Methods:
This research included patients admitted to Iwate Prefectural Rehabilitation and Nursery Center for Disabled Children. Serum 25-hydroxyvitamin D [25(OH)D] levels were assessed during school/outing restriction periods and after restriction removal and the introduction of sunbathing periods. The trends in 25(OH)D levels and oral VD intake before the two measurements were analyzed.
Results:
Although 17 of 32 patients had VD intake above the recommended level of Dietary Reference Intakes for Japanese during the first measurement, 31 patients had VD deficiency. The 25(OH)D levels of 13 patients without UV exposure before the first evaluation and those with UV exposure before the second evaluation were 2.03 times higher, despite of constant VD intakes. In contrast, there were no remarkable changes in both VD intakes and 25(OH)D levels in five patients without UV exposure before both assessments.
Conclusion:
Japanese children with severe disabilities who consume the recommended oral VD intake but who have limited UV exposure can still present VD deficiency.
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