Assessing bone mineral changes in response to vitamin D supplementation using natural variability in stable isotopes of Calcium in Urine

Ravi Rangarajan,Anura V Kurpad,Surajit Mondal,Prashanth Thankachan,Ramananda Chakrabarti

doi:10.1038/s41598-018-34568-4

Abstract

Osteoporosis is a chronic disease of public health importance, particularly in low and middle income countries. Measuring the bone mineral balance (BMB) in a non-invasive manner, and its response to different interventions, is critical to the definition of optimal strategies for its prevention and management. In this study, we demonstrate the usefulness of natural variability in calcium isotopes (δ44/40Ca) of urine and the derived BMB estimates as a biomarker of bone health and its responsiveness to interventions. Vitamin D3 is commonly used as a supplement for the prevention and treatment of osteoporosis, along with calcium supplements. We studied the effect of a short term vitamin D3 supplementation on changes in urine δ44/40Ca and the derived BMB. δ44/40Ca before and after the vitamin D3 supplementation yielded a statistically significant change (p = 0.050) with a positive δ44/40Ca enrichment. The mean derived BMB was net positive (0.04 ± 0.05) in comparison to a net negative value for the control group (−0.03 ± 0.01). These results indicate the potential usefulness of urinary natural δ44/40Ca and the derived BMB, which, along with bone mineral density could be used as a sensitive marker for precision in the prevention and treatment of osteoporosis.

Highlights

Osteoporosis, a chronic condition of public health importance is defined by the World Health Organisation (WHO) as a bone mineral density (BMD) at the hip and/or the spine region that is 2.5 standard deviations below that of healthy adults of the same age[1,2]
There is a need for more relevant markers of bone health, ideally, an adjunct marker to BMD that directly relates to bone metabolism, taking into account the processes of bone resorption and formation
We demonstrate the usefulness of Ca isotopes in urine and the derived bone mineral balance (BMB) estimates as a direct marker of bone health with potential implications for diseased conditions like osteoporosis

Summary

Introduction

Osteoporosis, a chronic condition of public health importance is defined by the World Health Organisation (WHO) as a bone mineral density (BMD) at the hip and/or the spine region that is 2.5 standard deviations below that of healthy adults of the same age[1,2] It is characterised by a reduction of bone mass and decrease of bone strength, eventually resulting in fragile bones and increased fracture risks[3,4]. There is a need for more relevant markers of bone health, ideally, an adjunct marker to BMD that directly relates to bone metabolism, taking into account the processes of bone resorption and formation

Methods

Results

Discussion

Conclusion