Vitamin D and K status influences bone mineral density and bone accrual in children and adolescents with celiac disease

Background/Objectives: Children with celiac disease (CD) are at risk for decreased bone mineral density (BMD) because of fat-soluble vitamin malabsorption, inflammation and/or under-nutrition. The study objective was to determine the interrelationships between vitamin K/D status and lifestyle variables on BMD in children and adolescents with CD at diagnosis and after 1 year on the gluten-free diet (GFD). Subjects/Methods: Children and adolescents aged 3-17 years with biopsy proven CD at diagnosis and after 1 year on the GFD were studied. BMD was measured using dual-energy X-ray absorptiometry. Relevant variables included: anthropometrics, vitamin D/K status, diet, physical activity and sunlight exposure. Results: Whole-body and lumbar-spine BMD-z scores were low (<=- 1) at diagnosis (10-20%) and after 1 year (30-32%) in the children, independent of symptoms. Whole-body BMD-z scores (-0.55 +/- 0.7 versus 0.72 +/- 1.5) and serum levels of 25(OH) vitamin D (90.3 +/- 24.8 versus 70.5 +/- 19.8 nmol/l) were significantly lower in older children (410 years) when compared with younger children (<= 10 years) (P<0.001). Forty-three percent had suboptimal vitamin D status (25(OH)-vitamin D <75 nmol/l) at diagnosis; resolving in nearly half after 1 year on the GFD. Twenty-five percent had suboptimal vitamin K status at diagnosis; all resolved after 1 year. Conclusions: Children and adolescents with CD are at risk for suboptimal bone health at time of diagnosis and after 1 year on GFD; likely due in part to suboptimal vitamin D/K status. Therapeutic strategies aimed at optimizing vitamin K/D intake may contribute to improved BMD in children with CD. European Journal of Clinical Nutrition (2012) 66, 488-495; doi:10.1038/ejcn.2011.176; published online 5 October 2011