Dose response to Vitamin D3 Supplementation on serum 25 hydroxy-vitamin D and Cardiometabolic Risk Factors in Obese Adolescents - A Prospective Double Blind Randomized Trial

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: MON 596-630-Pediatric Endocrinology
Clinical
Monday, June 17, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board MON-611
Asma Javed*1, Prabhakara P Balagopal2, Adrian Vella1, Philip Fischer1, Amy Weaver1, Jeanette Laugen1, Paula Giesler1 and Seema Kumar1
1Mayo Clinic, Rochester, MN, 2Res Div, Jacksonville, FL
Objective:Vitamin D deficiency and alterations in risk factors for cardiometabolic disease (CMD) are common early in the clinical course of obesity. Although there are studies on Vitamin D supplementation in obese children, there are none on the its dose response on serum 25 hydroxy-vitamin D [25(OH)D] and risk factors for CMD such as lipids and markers of insulin resistance and inflammation in obese adolescents.

Study Design: Double blind, randomized trial in 12-18 year old obese adolescents (BMI > 95th percentile). Participants were prospectively randomized to receive either 2000 IU/day (n=23) or 400 IU (n=23) vitamin  D3, orally for 12 weeks. Total [25(OH)D] and risk factors of CMD such as fasting plasma glucose, insulin, total cholesterol, high density cholesterol, triglycerides, high sensitivity C-reactive protein (hsCRP), interleukin- 6 (IL-6), total (T) adiponectin, high molecular weight (HMW) adiponectin and retinol binding protein 4 (RBP4) were measured at baseline and at the end of the 12 week supplementation.

Results: Mean 25(OH)D levels at baseline were similar in both groups. While the [25(OH)D] concentration increased ( median 5 ng/ml; range -8 to 15.1, p=0.039) in the 2000 IU/day group,  the change in the 400 IU/day group was negligible ( range -8 to 9, p=0.4). Irrespective of the dose of vitamin D3, the risk factors of CMD did not show any appreciable changes (all p>0.05) in both groups.

Conclusions: Although the higher dose of 2000 IU/day vs. 400 IU/day produced a modest increase in serum 25(OH)D, neither resulted in beneficial changes in obesity-related risk factors of CMD. These results are intriguing and suggest the potential need for higher doses of vitamin D in obese adolescents, particularly in those with vitamin D deficiency. On the other hand it is likely that the modulation of risk factors of obesity-related CMD is not solely dependent on vitamin D status in children. Considering obesity-related vitamin D insufficiency and the increased prevalence of CMD, it is crucial that future studies focus on higher doses of vitamin D and/or longer duration of supplementation along with more sophisticated measures of insulin resistance and other markers of CMD to understand the role of vitamin D in modulating alterations in risk factors of CMD in obese children and adolescents.

Nothing to Disclose: AJ, PPB, AV, PF, AW, JL, PG, SK

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