Please use this identifier to cite or link to this item: http://ahro.austin.org.au/austinjspui/handle/1/10752
Title: Skeletal and hormonal responses to sunlight deprivation in Antarctic expeditioners.
Authors: Iuliano-Burns, Sandra;Wang, X F;Ayton, J;Jones, G;Seeman, Ego
Affiliation: Austin Health, University of Melbourne, West Heidelberg, Australia. sandraib@unimelb.edu.au
Issue Date: 17-Jan-2009
Citation: Osteoporosis International : A Journal Established As Result of Cooperation Between the European Foundation For Osteoporosis and the National Osteoporosis Foundation of The Usa 2009; 20(9): 1523-8
Abstract: Serum 25(OH)D levels decline without sunlight exposure. We studied 120 expeditioners to Antarctica to determine the skeletal and hormonal responses to sunlight deprivation. With emerging vitamin D insufficiency, serum calcium decreased, PTH increased, and bone loss at the proximal femur was observed. Baseline serum 25(OH)D levels >100 nmol/L prevented vitamin D insufficiency.Vitamin D stores deplete without adequate sunlight exposure unless supplementation is provided. We studied 120 healthy adults who spent a year in Antarctica as a model for sunlight deprivation to define the timing and magnitude of the skeletal and hormonal responses to emerging vitamin D insufficiency.Fasting blood samples were assessed at baseline, 6 and 12 months for serum 25-hydroxyvitamin D (25(OH)D), osteocalcin (OC), bone formation (P1NP) and resorption (CTx), PTH and calcium. Lumbar spine and proximal femur BMD was measured using DXA. Differences over time were determined using repeated measures ANOVA. Percent changes were expressed as (Delta value/(value A + value B)/2) x 100. Relationships between outcome measures were determined using Spearman's correlations.Vitamin D insufficiency (<50 nmol/L) was observed in 85% of expeditioners by 6 months when serum calcium decreased and PTH increased (p < 0.01). By 12 months, OC increased by 7.4 +/- 3.0% (p < 0.05), and BMD decreased by 1.0 +/- 2.0% at the total proximal femur (p < 0.05). For those with vitamin D sufficiency at baseline (>50 nmol/L), sunlight deprivation produced vitamin D insufficiency within 4 months unless baseline values were >100 nmol/L.Supplementation may be necessary for expeditioners with limited access to UV light.
Internal ID Number: 19151911
URI: http://ahro.austin.org.au/austinjspui/handle/1/10752
DOI: 10.1007/s00198-008-0830-9
URL: http://www.ncbi.nlm.nih.gov/pubmed/19151911
Type: Journal Article
Subjects: Adult
Analysis of Variance
Antarctic Regions.epidemiology
Biological Markers.blood
Bone Resorption.epidemiology.etiology
Bone and Bones.metabolism
Dietary Supplements
Fasting.blood
Female
Humans
Male
Middle Aged
Osteocalcin.blood
Parathyroid Hormone.blood
Prospective Studies
Sunlight
Vitamin D.analogs & derivatives.biosynthesis.blood
Vitamin D Deficiency.blood.complications
Young Adult
Appears in Collections:Journal articles

Files in This Item:
File SizeFormat 
19151911.pdf53.72 kBAdobe PDFView/Open


Items in AHRO are protected by copyright, with all rights reserved, unless otherwise indicated.