Trial Outcomes & Findings for Effect of Vitamin D3 Supplementation on Insulin Resistance and Cardiovascular Risk Factors in Obese Adolescents (NCT NCT00858247)

NCT ID: NCT00858247

Last Updated: 2014-05-20

Results Overview

Insulin resistance (IR) is a physiological condition in which cells fail to respond to the normal actions of the hormone insulin. The body produces insulin, but the cells in the body become resistant to insulin and are unable to use it as effectively, leading to hyperglycemia. Beta cells in the pancreas subsequently increase their production of insulin, further contributing to hyperinsulinemia. From the fasting glucose and insulin measurements, insulin resistance was calculated by the homeostasis model assessment of insulin resistance (HOMA -IR) as: HOMA -IR = fasting insulin concentration (µU/mL) x fasting glucose concentration (mmol/L)/22.5. High HOMA-IR scores denote increased insulin resistance.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

51 participants

Primary outcome timeframe

Baseline, 12 weeks

Results posted on

2014-05-20

Participant Flow

Participants were enrolled at the Mayo Clinic in Rochester, Minnesota.

Participant milestones

Participant milestones
Measure
Vitamin D3-low Dose
Vitamin D3 400 IU capsule, one capsule daily Vitamin D3: One arm would receive vitamin D3 at a dose of 400 IU by mouth once daily for 12 weeks and the other arm would receive vitamin D3 as a single oral daily dose of 2000 IU for 12 weeks.
Vitamin D3-high Dose
Vitamin D3 2000 IU capsule, one capsule daily Vitamin D3: One arm would receive vitamin D3 at a dose of 400 IU by mouth once daily for 12 weeks and the other arm would receive vitamin D3 as a single oral daily dose of 2000 IU for 12 weeks.
Baseline Assessment
STARTED
25
26
Baseline Assessment
COMPLETED
23
24
Baseline Assessment
NOT COMPLETED
2
2
Week 12 Follow-up
STARTED
23
24
Week 12 Follow-up
COMPLETED
23
23
Week 12 Follow-up
NOT COMPLETED
0
1

Reasons for withdrawal

Reasons for withdrawal
Measure
Vitamin D3-low Dose
Vitamin D3 400 IU capsule, one capsule daily Vitamin D3: One arm would receive vitamin D3 at a dose of 400 IU by mouth once daily for 12 weeks and the other arm would receive vitamin D3 as a single oral daily dose of 2000 IU for 12 weeks.
Vitamin D3-high Dose
Vitamin D3 2000 IU capsule, one capsule daily Vitamin D3: One arm would receive vitamin D3 at a dose of 400 IU by mouth once daily for 12 weeks and the other arm would receive vitamin D3 as a single oral daily dose of 2000 IU for 12 weeks.
Baseline Assessment
Withdrawal by Subject
1
1
Baseline Assessment
Poor IV access
1
0
Baseline Assessment
Protocol Violation
0
1
Week 12 Follow-up
Withdrawal by Subject
0
1

Baseline Characteristics

Effect of Vitamin D3 Supplementation on Insulin Resistance and Cardiovascular Risk Factors in Obese Adolescents

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Vitamin D3-low Dose
n=23 Participants
Vitamin D3 400 IU capsule, one capsule daily
Vitamin D3-high Dose
n=24 Participants
Vitamin D3 2000 IU capsule, one capsule daily
Total
n=47 Participants
Total of all reporting groups
Age, Continuous
14.5 years
n=5 Participants
14.7 years
n=7 Participants
14.5 years
n=5 Participants
Sex: Female, Male
Female
9 Participants
n=5 Participants
18 Participants
n=7 Participants
27 Participants
n=5 Participants
Sex: Female, Male
Male
14 Participants
n=5 Participants
6 Participants
n=7 Participants
20 Participants
n=5 Participants
Region of Enrollment
United States
23 participants
n=5 Participants
24 participants
n=7 Participants
47 participants
n=5 Participants

PRIMARY outcome

Timeframe: Baseline, 12 weeks

Population: All subjects had blood drawn but some tests such as insulin could not be done in some cases due to sample issues. This lab test was calculated from other parameters and not drawn per se. If the values obtained did not allow a calculation of the lab test, then the results could not be reported.

Insulin resistance (IR) is a physiological condition in which cells fail to respond to the normal actions of the hormone insulin. The body produces insulin, but the cells in the body become resistant to insulin and are unable to use it as effectively, leading to hyperglycemia. Beta cells in the pancreas subsequently increase their production of insulin, further contributing to hyperinsulinemia. From the fasting glucose and insulin measurements, insulin resistance was calculated by the homeostasis model assessment of insulin resistance (HOMA -IR) as: HOMA -IR = fasting insulin concentration (µU/mL) x fasting glucose concentration (mmol/L)/22.5. High HOMA-IR scores denote increased insulin resistance.

Outcome measures

Outcome measures
Measure
Vitamin D3-low Dose
n=21 Participants
Vitamin D3 400 IU capsule, one capsule daily for 12 weeks.
Vitamin D3-high Dose
n=21 Participants
Vitamin D3 2000 IU capsule, one capsule daily for 12 weeks.
Change in Insulin Resistance After 12 Weeks of Vitamin D3 Supplementation
0.01 HOMA score
Standard Deviation 1.34
-0.27 HOMA score
Standard Deviation 4.95

SECONDARY outcome

Timeframe: baseline, 12 weeks

Population: One subject in the high-dose arm dropped out before the week 12 assessment, so the reporting population on the high dose arm was 23, not 24.

Less than 200 mg/dL is desirable, \>200 mg/dL is borderline high, \>240 mg/dL is High

Outcome measures

Outcome measures
Measure
Vitamin D3-low Dose
n=23 Participants
Vitamin D3 400 IU capsule, one capsule daily for 12 weeks.
Vitamin D3-high Dose
n=23 Participants
Vitamin D3 2000 IU capsule, one capsule daily for 12 weeks.
Change in Total Cholesterol After 12 Weeks of Vitamin D Supplementation
4.7 mg/dL
Standard Deviation 24.3
3.5 mg/dL
Standard Deviation 16.8

SECONDARY outcome

Timeframe: baseline, 12 weeks

Population: One subject in the high-dose arm dropped out before the week 12 assessment, so the reporting population on the high dose arm was 23, not 24.

LDL cholesterol is considered to be the main source of cholesterol buildup and blockage in the arteries. Less than 100 mg/dL is optimal, \>130 mg/dL is borderline high, \>160 mg/dL is high, \>190 mg/dL is very high.

Outcome measures

Outcome measures
Measure
Vitamin D3-low Dose
n=23 Participants
Vitamin D3 400 IU capsule, one capsule daily for 12 weeks.
Vitamin D3-high Dose
n=23 Participants
Vitamin D3 2000 IU capsule, one capsule daily for 12 weeks.
Change in Low Density Lipoprotein (LDL) Cholesterol After 12 Weeks of Vitamin D Supplementation
4.6 mg/dL
Standard Deviation 22.0
1.3 mg/dL
Standard Deviation 15.6

SECONDARY outcome

Timeframe: baseline, 12 weeks

Population: One subject in the high-dose arm dropped out before the week 12 assessment, so the reporting population on the high dose arm was 23, not 24.

HDL (good) cholesterol protects against heart disease, so for HDL, higher numbers are better. A level less than 40 mg/dL is low and is considered a major risk factor because it increases your risk for developing heart disease. HDL levels of 60 mg/dL or more help to lower your risk for heart disease.

Outcome measures

Outcome measures
Measure
Vitamin D3-low Dose
n=23 Participants
Vitamin D3 400 IU capsule, one capsule daily for 12 weeks.
Vitamin D3-high Dose
n=23 Participants
Vitamin D3 2000 IU capsule, one capsule daily for 12 weeks.
Change in High Density Lipoprotein (HDL) Cholesterol After 12 Weeks of Vitamin D Supplementation
1.3 mg/dL
Standard Deviation 6.8
1.9 mg/dL
Standard Deviation 5.7

SECONDARY outcome

Timeframe: baseline, 12 weeks

Population: One subject in the high-dose arm dropped out before the week 12 assessment, so the reporting population on the high dose arm was 23, not 24.

The current recommendation on fasting blood triglyceride levels: \< 150 mg/dL is normal, \>150 mg/dL is borderline high, and \>200 mg/dL is high.

Outcome measures

Outcome measures
Measure
Vitamin D3-low Dose
n=23 Participants
Vitamin D3 400 IU capsule, one capsule daily for 12 weeks.
Vitamin D3-high Dose
n=23 Participants
Vitamin D3 2000 IU capsule, one capsule daily for 12 weeks.
Change in Triglycerides After 12 Weeks of Vitamin D Supplementation
-4.7 mg/dL
Standard Deviation 56.7
1.7 mg/dL
Standard Deviation 43.5

SECONDARY outcome

Timeframe: baseline, 12 weeks

Population: One subject in the high-dose arm dropped out before the week 12 assessment, so the reporting population on the high dose arm was 23, not 24.

The high-sensitivity C-reactive protein test measures your risk for heart problems. \<1.0 mg/L is lowest risk, 1.0-3.0 mg/L is average risk, and \>3.0 mg/L is highest risk.

Outcome measures

Outcome measures
Measure
Vitamin D3-low Dose
n=23 Participants
Vitamin D3 400 IU capsule, one capsule daily for 12 weeks.
Vitamin D3-high Dose
n=23 Participants
Vitamin D3 2000 IU capsule, one capsule daily for 12 weeks.
Change in High-Sensitivity C-Reactive Protein After 12 Weeks of Vitamin D Supplementation
-0.2 mg/L
Standard Deviation 1.2
-0.5 mg/L
Standard Deviation 1.7

Adverse Events

Vitamin D3-low Dose

Serious events: 0 serious events
Other events: 1 other events
Deaths: 0 deaths

Vitamin D3-high Dose

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Other adverse events
Measure
Vitamin D3-low Dose
n=23 participants at risk
Vitamin D3 400 IU capsule, one capsule daily for 12 weeks.
Vitamin D3-high Dose
n=24 participants at risk
Vitamin D3 2000 IU capsule, one capsule daily for 12 weeks.
General disorders
Lightheaded and dizzy
4.3%
1/23 • Number of events 1 • Adverse events were collected over the duration of the study, an average of 12 weeks.
0.00%
0/24 • Adverse events were collected over the duration of the study, an average of 12 weeks.

Additional Information

Seema Kumar, MD

Mayo Clinic

Phone: 507-284-3300

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place