Change in Free 25(OH)D After High Dose in Vitamin D Deficient Postmenopausal Women

Launched by SHEFFIELD TEACHING HOSPITALS NHS FOUNDATION TRUST · Sep 16, 2015

Keywords

ClinConnect Summary

The most commonly used measurement of vitamin D status is serum 25-hydroxyvitamin D (25(OH)D). However there is no clear consensus on the level of 25(OH)D required to protect against adverse effects of deficiency.

One approach is to define deficiency is the level of 25(OH)D at which there is a secondary physiological response, such as a rise in parathyroid hormone. However, this approach has not yielded a clear answer. Total 25(OH)D below 30nmol/l is not always associated with an increased parathyroid hormone (PTH) response, and total 25(OH)D and PTH do not always respond to vitamin D supp...

Gender

FEMALE

Eligibility criteria

• Inclusion Criteria:
• • Caucasian
• • 25(OH)D \< 30nmol/l for treatment groups or 25(OH)D \>50nmol/l for control group
• • BMI between 20 kg/m2 and 30kg/m2
• • 55 years and over and postmenopausal (at least 5 years since last menstrual period)
• • Able and willing to participate in the study and provide written informed consent.
• Exclusion Criteria:
• • History of any long term immobilization (duration greater than three months)
• • Pre-diagnosed diabetes mellitus
• • High trauma fracture or low trauma fracture less than one year prior to recruitment
• * History of or current conditions known to affect vitamin D or bone metabolism, including:
• • Chronic renal disease Malabsorption syndromes Diagnosed endocrine disorders Hypercalcaemia Diagnosed restrictive eating disorder
• • Use of medications or treatment known to affect vitamin D or bone metabolism such as bisphosphonates or anti-epileptic medication.
• • Alcohol intake of greater than 21 units per week
• • Holiday with significant sunlight exposure in the last six weeks
• • Planned sun holiday within study period
• • Abnormal clinical laboratory parameters that are assessed as clinically significant by the PI.