Submitted to: Pediatrics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/12/2010
Publication Date: 6/8/2010
Citation: Liang, L., Chantry, C., Stephensen, C.B. 2010. Prevalence and risk factors For vitamin D deficiency among healthy infants in Sacramento, California. Pediatrics. 169:1337-1344. Interpretive Summary: Vitamin D deficiency is a problem in some areas of the US where sun exposure is minimal, particularly in the winter, and thus minimizes dermal vitamin D synthesis. Anecdotal evidence suggested that deficiency might also be a problem in California. This study examined the prevalence of vitamin D deficiency in healthy infants 6–18 m of age. The prevalence of severe deficiency (consistent with the development of rickets) was 2.9% and occurred exclusively in breastfed infants not receiving the recommended vitamin D supplementation. The prevalence of deficiency using a cut-off common in adults was 28.3% In summary, vitamin D deficiency does occur in a sunny, temperate region of California and could be prevented by appropriate use of supplements.
Technical Abstract: Objective: The purpose of this study was to assess the vitamin D status of healthy infants 6-18 months of age in Sacramento, CA. Patients and Methods: This was a one-year, cross-sectional study among a convenience sample of healthy infants seen at routine “well child” or follow-up appointments at the general pediatric clinic of the University of California, Davis Medical Center in Sacramento, CA (38.5° N latitude). Blood was collected from the infant. Information on feeding practices, sun exposure and other variables was collected from the caregiver present at the appointment. Results: The mean ± SD age of the 173 subjects was 12.4 ± 2.9 months and 49% were female. The most common ethnic groups were Hispanic (27%), Mixed (26%), and White (26%) followed by Black (14%) and Asian/Pacific Islander (7%). The mean ± SD 25(OH)D was 95 ± 39 nmol/L; 5 infants (2.9%) had plasma 25(OH)D < 27.5 nmol/L, 14 (8.1%) were <50 nmol/L, and 49 (28.3%) were <75 nmol/L. Most infants (154; 88%) received some vitamin D-fortified cow’s milk or formula while 19 infants (11%) received breastmilk as the only milk source. Breastfeeding was significantly associated with greater risk of vitamin D deficiency. Subjects with plasma 25(OH)D < 27.5 nmol/L had significantly higher plasma parathyroid hormone (PTH) concentrations than did other subjects. Only 4 of 35 breastfed infants consuming < 500 ml vitamin D fortified formula or milk received the recommended vitamin D supplements. Conclusions: Vitamin D deficiency with elevated PTH remains a risk for breastfed infants not receiving supplemental vitamin D in California. Strategies to provide supplementation soon after birth may decrease the risk of vitamin D deficiency for infants.