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Vitamin D, C-reactive Protein and Insulin Resistance

This study has been completed.
Instituto Mexicano del Seguro Social
Ellison Medical / International Nutrition Foundation
Tufts University
Information provided by:
Instituto Nacional de Salud Publica, Mexico Identifier:
First received: November 23, 2009
Last updated: NA
Last verified: November 2009
History: No changes posted

Randomized, double blind, placebo-controlled clinical trial of vitamin D supplementation (cholecalciferol, 4,000 IU/day for 6 months, in 104 postmenopausal women with type 2 diabetes mellitus.

The objective was to evaluate the effect of vitamin D supplementation on C-reactive protein (CRP) and insulin resistance in women with type 2 diabetes mellitus (T2DM).

The trial was conducted from March to October 2008 at the Hospital of the Mexican Social Security in Cuernavaca, Mexico.

Condition Intervention Phase
Low-intensity Chronic Inflammation
Insulin Resistance
Drug: cholecalciferol
Drug: placebo
Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Effect of Vitamin D Supplementation on C-reactive Protein and Insulin Resistance in Postmenopausal Women With Type 2 Diabetes Mellitus

Resource links provided by NLM:

Further study details as provided by Instituto Nacional de Salud Publica, Mexico:

Primary Outcome Measures:
  • Serum C-reactive protein concentrations, measured by a high-sensitivity assay -nephelometry-. [ Time Frame: 3 and 6 months ]
  • Insulin resistance, measured by HOMA-IR index [ Time Frame: 3 and 6 months ]

Secondary Outcome Measures:
  • Serum 25-OH-vitamin D3 levels [ Time Frame: 3 and 6 months ]

Enrollment: 104
Study Start Date: March 2008
Study Completion Date: October 2008
Primary Completion Date: October 2008 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Vitamin D
Cholecalciferol, 4,000 IU/d for 6 months
Drug: cholecalciferol
4,000 IU per day during 6 months. Capsule form.
Placebo Comparator: Placebo
Drug: placebo
no active principles given.

Detailed Description:

Methods. Randomized, double blind, placebo-controlled clinical trial. We selected 104 postmenopausal women, ages 45 to 65, with uncomplicated T2DM and BMI ≥25. Women with history of kidney or liver disease, BMI>40, autoimmune disease or cancer were not included in the study.

Participants were randomly assigned to receive either a capsule containing 4,000 IU of vitamin D3 (cholecalciferol, n=52) or placebo (n=52), once a day during 6 months.

Outcome variables were serum CRP, measured with a high-sensitivity assay (nephelometry), and HOMA-IR. Serum vitamin D (25-OH-D) was measured by HPLC. Outcome variables were measured at baseline, and 3 and 6 months thereafter. All participants received diet and physical activity counseling, and visited the clinic for medical check-up once a month.

Baseline Results. Mean age was 56.8 ± 5.1 y. Baseline BMI was 30.7 ± 3.9. Median CRP concentration was 5.0 mg/L (Interquartile range: 1.0, 8.5). HOMA index at baseline was 7.13 ± 3.8. Serum 25-OH-D concentration at baseline was 54.5 ± 15.7 nmol/L (~22 ng/mL). Almost 94% of patients had baseline serum 25-OH-D levels <80 nmol/L, and 25% were below 40 nmol/L. No one had levels <20 nmol/L. There were no statistical differences on important variables by treatment group at the onset of study.


Ages Eligible for Study:   45 Years to 65 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Type 2 diabetes mellitus w/ < 10 yrs of diagnosis
  • Postmenopausal
  • Overweight or obesity (BMI >=25)
  • Treated with metformin

Exclusion Criteria:

  • BMI >=40
  • Liver or kidney disease
  • Other important chronic disease: i.e. cancer, autoimmune.
  • Receiving insulin
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Please refer to this study by its identifier: NCT01019642

Instituto Mexicano del Seguro Social
Cuernavaca, Morelos, Mexico, 62450
Sponsors and Collaborators
Instituto Nacional de Salud Publica, Mexico
Instituto Mexicano del Seguro Social
Ellison Medical / International Nutrition Foundation
Tufts University
Principal Investigator: Mario E Flores, MD, MSc Instituto Nacional de Salud Publica, Mexico
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Mario E. Flores, Instituto Nacional de Salud Publica Identifier: NCT01019642     History of Changes
Other Study ID Numbers: 120-6371
Study First Received: November 23, 2009
Last Updated: November 23, 2009

Keywords provided by Instituto Nacional de Salud Publica, Mexico:
vitamin D
C-reactive protein
insulin resistance

Additional relevant MeSH terms:
Insulin Resistance
Pathologic Processes
Glucose Metabolism Disorders
Metabolic Diseases
Vitamin D
Hypoglycemic Agents
Physiological Effects of Drugs
Growth Substances
Bone Density Conservation Agents processed this record on May 25, 2017