Efficacy of an oral, 10-day course of high-dose calciferol in correcting vitamin D deficiency

Abstract

Aim: Treatment of vitamin D deficiency is an important aspect of the management of osteoporosis, particularly in the elderly. Most well-described regimens in current use involve daily dosing and thus require long-term compliance to be effective. In New Zealand, no preparation containing only low-dose vitamin D suitable for daily use is available. We describe a high-dose regimen for rapid correction of vitamin D deficiency, which makes use of the calciferol 50 000 international unit (IU) tablets available in this country.

Methods: Thirty two women (mean age 76 +/- 4 years; range 67-84 years) with serum 25-hydroxyvitamin D concentrations = or <10 microg/l were treated with oral calciferol 50 000 IU daily for 10 days.

Results: At an average time after treatment of four months, serum 25-hydroxyvitamin D increased from 8 +/- 1 microg/l to 21 +/- 5 microg/l, bringing all but one patient within the reference range (14-76 microg/l). Serum parathyroid hormone level decreased after treatment by 0.7 +/- 1.7 pmol/l (p <0.05), and alkaline phosphatase activity decreased by 5 +/- 11 u/l (p <0.05). Serum calcium increased by 0.06 +/- 0.08 mmol/l (p <0.001), but all values were within the reference range. Data collected from a separate cohort of elderly inpatients showed that similar increases could be achieved with a single 300 000 IU dose, and suggested that serum 25-hydroxyvitamin D levels decline with a half-life of 90 days.

Conclusions: This regimen provides a simple, safe and effective way of managing vitamin D deficiency. Its short-term nature may result in higher compliance than daily dosing regimens.