title: Safety and Efficacy of High-dose Daily Vitamin D3 Supplementation in Children and Young Adults With Sickle Cell Disease.
abstract: Suboptimal vitamin D (vit D) status (<32 ng/mL) is ubiquitous among African American children with type SS sickle cell disease (SCD-SS). The vit D supplemental dose to normalize vit D status is unknown. Five to 20-year-old African American children with (n=21) and without (n=23) SCD-SS were randomized to vit D3 supplementation (4000 or 7000 IU/d) and evaluated at 6 and 12 weeks for changes in vit D and SCD status. A dose was considered unsafe if serum calcium was elevated associated with elevated serum 25 hydroxyvitamin D (25(OH)D). At baseline 95% of subjects with SCD-SS and 87% of healthy controls had suboptimal vit D status (mean±SD, 19.2±7.2 and 22.3±9.3 ng/mL, respectively). After 12 weeks supplementation, both D3 doses were safe and well tolerated. Neither group achieved the a priori efficacy criterion of 25(OH)D≥32 ng/mL in >80% of subjects (45% in SCD-SS and 63% in controls). However, for both subjects with SCD-SS and healthy subjects by 12 weeks, deficient (<20 ng/mL) vit D status was eliminated only in those receiving 7000 IU/d. For subjects with SCD-SS, by 12 weeks there was a significant (all P<0.05) increase in fetal hemoglobin, decrease in high-sensitivity C-reactive protein, and reduction in the percentage of subjects with a high platelet count.
authors.affiliation: *The School of Health Sciences, The Richard Stockton College of New Jersey, Galloway, NJ †University Hospital Umberto I, Sapienza University, Rome, Italy ‡Department of Pediatrics, Division of Gastroenterology, Hepatology and Nutrition §Division of Hematology, Children's Hospital of Philadelphia ∥Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA.
authors.forename: Kelly A
authors.initials: KA
authors.lastname: Dougherty
authors.forename: Chiara
authors.initials: C
authors.lastname: Bertolaso
authors.forename: Joan I
authors.initials: JI
authors.lastname: Schall
authors.forename: Kim
authors.initials: K
authors.lastname: Smith-Whitley
authors.forename: Virginia A
authors.initials: VA
authors.lastname: Stallings
mesh_terms: D000293:Adolescent; D000755:Anemia, Sickle Cell / Q000097:blood*; D002097:C-Reactive Protein / Q000032:analysis / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D002762:Cholecalciferol / Q000008:administration & dosage*; D002851:Chromatography, High Pressure Liquid; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood; D014815:Vitamins / Q000008:administration & dosage*
chemical_list: D014815:Vitamins; D014807:Vitamin D; D002762:Cholecalciferol; D002097:C-Reactive Protein; C104450:25-hydroxyvitamin D