Impact of Vitamin D Supplementation on Lactation Associated Bone Loss

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SUN 257-280-Disorders of Vitamin D Metabolism & Action
Basic/Translational
Sunday, June 16, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SUN-275
Candice Rose*1, Leigh Marie Eck1, Leland Graves1 and Barbara P Lukert2
1The University of Kansas Medical Center, Kansas City, KS, 2The University of Kansas Medical Center, Westwood, KS
Purpose:

Lactation is a period of normal physiologic loss of bone mass in pre-menopausal women with subsequent recovery of bone mass in the post weaning period.  However, interventions that diminish this physiologic bone loss with lactation or positively impact the recovery of bone mass after weaning may result in higher peak bone mass, which could diminish future fracture risk.  The aims of this study were to determine if:  1. Supplementation with 4,000IU vitamin D3 during lactation had a significant impact on vitamin D stores as compared to a control group.  2. Supplementation with 4,000IU vitamin D3 during lactation would diminish lactation associated bone loss.

Methods:

Post-partum (PP) women within 1 month of delivery whom intended to breast feed at least 6 months were randomized to an intervention group supplemented with vitamin D3 4,000IU/daily and a multivitamin (MVI) versus a control group supplemented with a daily MVI alone.  The primary outcome measure of this study was change in absolute bone mineral density (BMD).  BMD measurements were undertaken at baseline, and months 3, 6, 12, and 18 PP.  Subjects were being followed through 18 months PP to ascertain what effect our intervention had on the recovery of bone mass that occurs post-weaning.  A secondary outcome of the study was change in 25-OH vitamin D at baseline and months 3 and 6 PP in the intervention group as compared to the control group.

Results:

Twenty-two PP women were randomized to vitamin D3 (N=12) versus the control group (N=10).  Two women have been lost to follow up; 1 due to pregnancy and 1 due to difficulty making appointments related to childcare.  No difference in change in BMD was found at 3 or 6 months PP in the intervention group as compared to the control group.  There was a significant difference in 25-OH vitamin D levels at 3 months between the groups.  25-OH vitamin D levels decreased from 33.6 to 27.15 ng/ml at 3 months in the control group, while increasing from 37.55 to 40.8 ng/ml in the treatment group.

Conclusions:

In a cohort of lactating women whom had a baseline mean 25-OH vitamin D level in a sufficient status, supplementation with 4,000IU vitamin D3 resulted in a statistical improvement in 25-OH vitamin D status as compared to a control group receiving 400IU vitamin D3 whom had a decline in 25-OH vitamin D3 status to an insufficient range (<32ng/mL).  In a short term analysis, no significant differences were noted in the change scores of BMD at the hip or spine.

Nothing to Disclose: CR, LME, LG, BPL

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm