Determination of Vitamin D Dose to Maintain Sufficiency Amongst Indian and Malay Women in the Tropics

Summary

Much research on vitamin D status has focused on seasonal variations in serum 25(OH)D levels in populations living at high altitudes and those of light-skinned Caucasian extraction, with little work done in multi ethnic populations living closer to the equator with regards to Vitamin d supplementation, prevalence, predictors and associations of hypovitaminosis D - the assumption, perhaps being vitamin D deficiency is unlikely in locations of plentiful sunshine. There is a dearth of studies on Vitamin D status in a group of subjects at especially high risk of falls/fractures i.e. post-menopausal women with osteoporosis living in South-East Asia. It is possible that differences in geography and ethnicity/culture amongst women with post menopausal osteoporosis (PMO) in Malaysia may necessitate supplemental Vitamin D doses that differ from those prescribed to North American Caucasians.

There is no unified consensus on the dose of Vitamin D supplementation. Neither is there agreement on definitions of sufficiency with some researchers targeting levels of serum 25(OH)D of \>20ng/ml and others aiming for levels above 30ng/ml. The Institute of Medicine (IOM) 2010 guidelines, aiming for a lower serum 25(OH)D target of 20ng/ml, advocates maintenance doses of 600 IU/day in Postmenopausal women aged 51-70 and 800 IU/day for those aged \>70 years. On contrary, the Endocrine Society 2011 guidelines state that maintenance doses up to 1500-2000 IU/day may be required to attain a higher optimal target of \>30ng/ml. On addition, the 2014 National Osteoporosis Foundation Guidelines recommended that the Vitamin D level should be brought up to approximately 30ng/ml, and to maintain at this level taking into account those with limited sun exposure, obese and dark skin individuals, the daily requirement ranges from 800-2000 IU/day.

The investigators therefore designed a prospective randomized controlled trial comparing efficacy and safety of a low (900 IU/day) and high (1800IU/day and 3300IU/day) maintenance dose of Cholecalciferol (Vitamin D3) amongst community dwelling Indian and Malay with PMO living in Kuala Lumpur, Malaysia.

Hypothesis of the study is despite abundant exposure to sunlight, which is the main Vitamin D supplier, those who dress conservatively and individuals with darker skin may require a higher dose of Vitamin D to maintain sufficiency (\>30ng/ml).

Conditions

• Vitamin D Deficiency

Interventions

DRUG

Vitamin D3

The drug/dosage of Vitamin D3 will be given monthly or bi-weekly depending on the type of arm that the subjects are randomised into under direct supervision.

Sponsors & Collaborators

• Universiti Teknologi Mara

  collaborator OTHER

• Sharifah Faradila bt Wan Muhamad Hatta

  lead OTHER

Principal Investigators

• Shireene Ratna Vethakkan, MBBS,MMED,MD · University of Malaya Medical Centre

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

45 Years

Max Age

75 Years

Sex

FEMALE

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2014-08-31

Primary Completion

2016-07-31

Completion

2016-07-31

Countries

• Malaysia

Study Locations