Which is the best oral high dose vitamin D3 regimen for postmenopausal women with hypovitaminosis D?

MASTAGLIA SR; SEIJO M; BAGUR A; SOMOZA J; OLIVERI B

Montreal

Congreso; 30th Meeting ASBMR; 2008

ASBMR

Hypovitaminosis D is a common problem in postmenopausal and elderly people. Intermittent administration of vitamin D is being studied as a means to ensure compliance with the supplementation regimen and to ensure adequate levels. The aim of this study was to assess the effectiveness and safety of two high-dose oral intermittent vitamin D3 regimens. Sixteen healthy postmenopausal women aged 58.4¡À5.0 years (X¡ÀSD), with 25OHD <20ng/ml, not receiving any treatment known to affect bone metabolism were recruited. They were randomly assigned to one of two groups: Group1 receiving a single 100.000IU dose of cholecalciferol (D3) and Group 2 receiving an additional similar dose on day 45. Serum calcium, phosphorus, bone alkaline phosphatase, iPTH and urinary Calcium/creatinine were measured at baseline (previous to D3 administration), and at 45 and 90 days. Average 25OHD levels rose from 14.5¡À4.3 ng/ml at baseline to 20.1¡À3.0 ng/ml at day 45 (p<0.004), and to 24.7¡À5 at day 90 (p<0.001vs. baseline) in all the patients. When divided according to regimen both groups had similar values at 45 days (G1=20.0¡À4 and G2:20.2 ¡À 2ng/ml) Group 1 maintained vitamin D levels between day 45 and 90 (23.0¡À4 ng/ml; ns); only 9% reached 25OHD levels ¡Ý30ng/ml. Group 2 showed a significant increase in 25OHD levels between day 45 and 90 (28.5¡À3 ng/ml; p<0.04). Forty percent of women had 25OHD levels ¡Ý30ng/ml. No significant differences in the remaining biochemical parameters were observed between groups at any time point and all the values were within the reference range for postmenopausal women. A single oral 100.000IU dose of cholecalciferol is safe but not sufficient. A second similar dose administered at 45 days improves 25OHD levels but is still not enough for healthy postmenopausal women with hypovitaminosis D to reach adequate 25OHD levels.