Effect of vitamin D treatment on the improvement of metabolic syndrome

ISRCTN ISRCTN21527585
DOI https://doi.org/10.1186/ISRCTN21527585
Secondary identifying numbers NCT
Submission date
20/12/2011
Registration date
16/01/2012
Last edited
16/09/2016
Recruitment status
No longer recruiting
Overall study status
Completed
Condition category
Nutritional, Metabolic, Endocrine
Prospectively registered
Protocol
Statistical analysis plan
Results
Individual participant data

Plain English summary of protocol

Background and study aims
Altered vitamin D levels are associated with an increased risk of obesity, high blood pressure and diabetes (also known as metabolic syndrome). Low levels of vitamin D (hypovitaminosis D) are also a risk factor for heart disease and death. The northern Chinese population have an increased risk of hypovitaminosis D due to their darker skin pigmentation and living at a northern latitude. Few studies have focused on the effect of vitamin D supplements on obesity and related metabolic disorders in Chinese populations. The aims of this study are to examine the relationship between vitamin D levels and obesity and other metabolic risk factors, and to find out whether vitamin D supplements improve metabolic disorders in patients with metabolic syndrome and hypovitaminosis D.

Who can participate?
People aged 35-60 who visit the healthcare department of Jinan Central Hospital for their annual health examination

What does the study involve?
Participants’ weight, height, waist circumference and blood pressure are measured. A blood sample is collected for measurement of vitamin D, glucose (sugar), insulin, fat and cholesterol levels. Participants with metabolic syndrome and hypovitaminosis D are randomly allocated to take either vitamin D and calcium supplements or a placebo (dummy drug) for 12 weeks. Both groups receive a lifestyle intervention provided by a dietitian. The dietitian meets the participants at 2-week intervals to assess their compliance with the lifestyle intervention program and provide additional study products (vitamin D, calcium or placebos). At the end of the 12 weeks, the two groups undergo the same tests as at the start of the study.

What are the possible benefits and risks of participating?
All participants receive a lifestyle intervention which may improve their health and physical function. The participants who receive vitamin D and calcium supplements may improve their vitamin D levels. There are no known risks to participants.

Where is the study run from?
Jinan Central Hospital (China)

When is the study starting and how long is it expected to run for?
January to April 2012

Who is funding the study?
1. Science and Technical Bureau of Jinan (China)
2. Health Department of Shandong (China)

Who is the main contact?
Dr Xiao Yin

Contact information

Dr Xiao Yin
Scientific

Shandong University
27 Shanda Nanlu
Shandong
Jinan
250100
China

Study information

Study designCross-sectional cohort single-center interventional randomised double blind placebo-controlled crossover study
Primary study designInterventional
Secondary study designRandomised controlled trial
Study setting(s)Hospital
Study typeTreatment
Participant information sheet Not available in web format, please use the contact details to request a patient information sheet
Scientific titleEffect of vitamin D treatment on the improvement of metabolic syndrome: a randomized single-blind trial
Study objectives1. Are the vitamin D levels associated with indices of adiposity and metabolic risk factors in a representative sample of the urban young and middle-aged non-diabetic adults residing in northern China?
2. Evaluate the prevalence of subclinical vitamin D deficiency in this cohort
3. Does vitamin D supplementation, in a randomized double-blind intervention trial, improve metabolic disorders in metabolic syndrome individuals with hypovitaminosis D.
Ethics approval(s)Ethics Committee of Shandong University Affiliated Jinan Central Hospital, China, 14/12/2011 ref: 2011026
Health condition(s) or problem(s) studiedMetabolic syndrome
InterventionAnthropometric measures (weight, height, waist circumference) and blood pressure will be measured on all participants. A fasting blood sample will be collected for measurement of serum 25-hydroxy vitamin D, plasma glucose, insulin, triglyceride, low density lipoprotein (LDL) cholesterol and high density lipoprotein (HDL) cholesterol concentrations.

For the randomized treatment portion of the study, 40-50 metabolic syndrome patients with hypovitaminosis D will be assigned, in a random double-blind manner, to receive either vitamin D treatment (vitamin D treatment group) or placebo (control group). Those in the vitamin D treatment group receive an oral dose of 500 IU vitamin D3 (cholecalciferol) and 1200mg calcium daily for 12 weeks. Both groups will be provided lifestyle intervention by a dietitian, At the end of the 12 weeks, subjects in the two groups will be re-evaluated for the same parameters measured at baseline.
Intervention typeOther
Primary outcome measure1. Weight, height, waist circumference and blood pressure
2. Body mass index (BMI)
3. Serum 25(OH)D and insulin, measured by double antibody radioimmunoassay
4. Plasma glucose, triglycerides, and HDL cholesterol, measured by enzymatic colorimetric assay
Secondary outcome measuresLDL cholesterol, calculated using the Friedwald equation
Overall study start date01/01/2012
Completion date01/04/2012

Eligibility

Participant type(s)Patient
Age groupAdult
SexBoth
Target number of participants500-600 participants will be enrolled in the observation study, then from the same cohort, 40-50 participants will be enrolled in interventional trial.
Key inclusion criteria1. Male and female participants
2. Aged 35-60 years old
3. Living in Jinan, China for more than 5 years
4. Employed in an office setting
5. Has had more than 13 years of education
Key exclusion criteria1. Use of vitamin D and calcium supplementation within 60 days of screening
2. Current use of cigarettes (self-report)
3. Alcohol abuse (defined as >14 drinks/week for men, >7 drinks/week for women)
4. Diagnosis of overt diabetes, cardiovascular disease or other systematic disease
5. Use of medications that influence vitamin D, glucose, lipid profiles or blood pressure
6. Engaging in more than 20 minutes of strenuous physical activity or exercise that causes excessive breathing and sweating more than once per week
Date of first enrolment01/01/2012
Date of final enrolment01/04/2012

Locations

Countries of recruitment

  • China

Study participating centre

Shandong University
Jinan
250100
China

Sponsor information

Shandong University (China)
University/education

Jinan Central Hospital
Jiefang road 105
Jinan
250013
China

Website http://www.sdu.edu.cn/english/
ROR logo "ROR" https://ror.org/0207yh398

Funders

Funder type

Government

Jinan Technology Star Program, Science and Technical Bureau of Jinan (China)

No information available

Shandong Province Medical and Health Development Program (China)

No information available

Results and Publications

Intention to publish date
Individual participant data (IPD) Intention to shareNo
IPD sharing plan summaryNot provided at time of registration
Publication and dissemination planNot provided at time of registration
IPD sharing plan

Study outputs

Output type Details Date created Date added Peer reviewed? Patient-facing?
Results article results 09/09/2012 Yes No

Editorial Notes

16/09/2016: Plain English summary added.