Prevention of Vitamin D Insufficiency in Subjects Living in Antarctica for One Year

G. BRITO; V. FERRO; C. M¨¦NDEZ NAVARRO; L. GUERRERO; M PARISI; J SOMOZA; C MAUTALEN; B. OLIVERI

Denver - Colorado

Congreso; 31th Anual Meeting ASBMR; 2009

ASBMR

Hypovitaminosis D is a major worldwide public health problem. Individuals may haveadequate vitamin D levels for optimal health throughout their entire life. Previousstudies showed that 25 hydroxyvitamin D(25OHD) levels of healthy men living inAntarctica for 1 year decreased by ¡Ö46%, reaching minimum levels between 10-15ng/ml of 25 OHD in subjects on different Antarctica bases (Oliveri B. et al. EJCN1994)(Oliveri B. et al EJCN 1999), and failed to increase even after the onset ofsummer.The aim of this study was to evaluate the effectiveness and safety of intermittentvitamin D3 supplementation to attain and maintain adequate 25OHD levels during the2008 Antarctica campaign.Twelve healthy volunteers aged (X¡ÀSD) 33.7 ¡À 5.6 years, BMI: 28.0 ¡À 4.6 kg/m2, leftBuenos Aires (BA) (latitude 34¡ãsouth) in December 2007, arriving on Orcadas Base(latitude 60¡ãsouth) in January 2008, where they stayed for one year and returned to BAin February 2009. All the participants signed an informed consent form prior to thestudy. Fasting blood samples were collected in BA (at baseline and on return) and fourtimes during their stay in Antarctica (March, June, September, and December) toperform calcium, phosphate, total alkaline phosphatase (AP), bone alkaline phosphatase(BAP) and 25OHD determinations.The study population was divided into two groups according to supplementationregimen: Group 1 (n=6) received a D3 dose of 100.000 IU monthly from March toAugust 2008. Group 2 (n=6) received a D3 dose of 200.000 IU every two months fromMarch to July; samples were collected prior to D3 administration.Calcium, phosphate, AP, and BAP values remained within normal range withoutsignificant variations throughout the Antarctic Campaign. 25OHD patterns were similarin both supplementation regimens. The average 25OHD levels corresponding to theentire population are shown in figure 1. Conclusion:Both supplementation regimenswere effective in attaining 25OHD levels similar to those observed in BA in summer,and maintaining them until September 2008. Thus, we suggest administering a newdose in September.