Trial Outcomes & Findings for D Vitamin Intervention in VA (NCT NCT01375660)

Results Overview

Oral glucose insulin sensitivity = index of insulin sensitivity, higher index means higher insulin sensitivity. Low insulin sensitivity means high insulin resistance and high risk of type 2 diabetes mellitus. It is calculated by a special formula using insulin and glucose measured in Oral Glucose Tolerance test. The primary outcome was the change in oral glucose insulin sensitivity (OGIS, from oral glucose tolerance test) after 12 months of treatment calculated as OGIS at 12-months minus OGIS baseline.

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

205 participants

Primary outcome timeframe

12 months

Results posted on

2015-03-06

Participant Flow

Participants were recruited among African American Male veterans coming for medical care to Jesse Brown VA Medical Center in Chicago between May 2011 and December 2012.

Participant milestones

Participant milestones
Measure	Placebo supplement of vitamin D 400 units provided to all subjects in addition to placebo.	50K Vitamin D2 supplement of vitamin D 400 units provided to all subjects in addition to 50K vitamin D2.
Overall Study STARTED	102	103
Overall Study COMPLETED	86	87
Overall Study NOT COMPLETED	16	16

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

D Vitamin Intervention in VA

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	Placebo n=86 Participants Supplement of vitamin D 400 units provided to all subjects in addition to placebo.	50K Vitamin D2 n=87 Participants Supplement of vitamin D 400 units provided to all subjects in addition to D2 50K.	Total n=173 Participants Total of all reporting groups
Age, Customized 35-85 Years	86 participants n=5 Participants	87 participants n=7 Participants	173 participants n=5 Participants
Sex/Gender, Customized Male	86 participants n=5 Participants	87 participants n=7 Participants	173 participants n=5 Participants
Race/Ethnicity, Customized African American Male Veterans	86 participants n=5 Participants	87 participants n=7 Participants	173 participants n=5 Participants
Region of Enrollment United States	86 participants n=5 Participants	87 participants n=7 Participants	173 participants n=5 Participants
BMI	31.5 Kg/m2 STANDARD_DEVIATION 2.4 • n=5 Participants	32.4 Kg/m2 STANDARD_DEVIATION 2.9 • n=7 Participants	31.9 Kg/m2 STANDARD_DEVIATION 2.65 • n=5 Participants
HbA1c	6.1 Percentage of A1C STANDARD_DEVIATION 0.20 • n=5 Participants	6.1 Percentage of A1C STANDARD_DEVIATION 0.26 • n=7 Participants	6.1 Percentage of A1C STANDARD_DEVIATION 0.26 • n=5 Participants
Vit D	14.0 ng/ml STANDARD_DEVIATION 4.8 • n=5 Participants	14.7 ng/ml STANDARD_DEVIATION 4.7 • n=7 Participants	14.3 ng/ml STANDARD_DEVIATION 4.8 • n=5 Participants

PRIMARY outcome

Timeframe: 12 months

Oral glucose insulin sensitivity = index of insulin sensitivity, higher index means higher insulin sensitivity. Low insulin sensitivity means high insulin resistance and high risk of type 2 diabetes mellitus. It is calculated by a special formula using insulin and glucose measured in Oral Glucose Tolerance test. The primary outcome was the change in oral glucose insulin sensitivity (OGIS, from oral glucose tolerance test) after 12 months of treatment calculated as OGIS at 12-months minus OGIS baseline.

Outcome measures

Outcome measures
Measure	Placebo n=86 Participants Supplement of vitamin D 400 units provided to all subjects in addition to Placebo.	50K Vitamin D2 n=87 Participants Supplement of vitamin D 400 units provided to all subjects in addition to D2 50K.
Oral Glucose Insulin Sensitivity (OGIS)	-16.0 ml/min/m^2 of body surface area Standard Deviation 55.83	7.8 ml/min/m^2 of body surface area Standard Deviation 56.02

SECONDARY outcome

Timeframe: Baseline and 12 Months

Outcome measures

Outcome measures
Measure	Placebo n=86 Participants Supplement of vitamin D 400 units provided to all subjects in addition to Placebo.	50K Vitamin D2 n=87 Participants Supplement of vitamin D 400 units provided to all subjects in addition to D2 50K.
Change in HbA1c From Baseline at 12 Months	0.01 percentage of A1C Standard Deviation 0.21	-0.01 percentage of A1C Standard Deviation 0.18

SECONDARY outcome

Timeframe: 12 Months

Insulin Sensitivity by Matsuda Composite - index of insulin sensitivity, higher index means higher insulin sensitivity. Low insulin sensitivity means high insulin resistance and high risk of type 2 diabetes mellitus. It is calculated by a special formula using insulin and glucose measured in Oral Glucose Tolerance test. The formula is different from a formula for OGIS. Matsuda composite calculated based on formula 10\^4/Square Root of \[(fasting glucose x fasting insulin) x (mean glucose x mean insulin)\] (Matsuda M, DeFronzo RA. Insulin sensitivity indices obtained from oral glucose tolerance testing: comparison with the euglycemic glucose clamp. Diabetes Care. 1999;22:1462-1470) Unit of measure is 10000/√\[(µU/mL)/(mg/dL)\]x\[(µU/mL)/(mg/dL)\].

Outcome measures

Outcome measures
Measure	Placebo n=86 Participants Supplement of vitamin D 400 units provided to all subjects in addition to Placebo.	50K Vitamin D2 n=87 Participants Supplement of vitamin D 400 units provided to all subjects in addition to D2 50K.
Insulin Sensitivity by Matsuda Composite	0.13 10^4/√[(µU/mL)/(mg/dL)x(µU/mL)/(mg/dL)] Standard Deviation 1.43	0.44 10^4/√[(µU/mL)/(mg/dL)x(µU/mL)/(mg/dL)] Standard Deviation 1.51

SECONDARY outcome

Timeframe: 12 Month

Index of insulin secretion, higher index means higher insulin secretion. It is calculated by a special formula using insulin and glucose measured at 0 min and at 30 min (hence 30 in the name) in Oral Glucose Tolerance test. Insulin secretion was assessed based on formula Insulinogenic index-30 \[(insulin at 30 min - fasting insulin)/(glucose at 30 min - fasting glucose)\] (Kosaka K, Hagura R, Kuzuya T. Insulin responses in equivocal and definite diabetes, with special reference to subjects who had mild glucose intolerance but later developed definite diabetes. Diabetes. 1977;26:944-952)

Outcome measures

Outcome measures
Measure	Placebo n=86 Participants Supplement of vitamin D 400 units provided to all subjects in addition to Placebo.	50K Vitamin D2 n=87 Participants Supplement of vitamin D 400 units provided to all subjects in addition to D2 50K.
Insulinogenic Index-30	-0.03 (µU/mL)/(mg/dL) Standard Deviation 1.10	0.26 (µU/mL)/(mg/dL) Standard Deviation 1.03

SECONDARY outcome

Timeframe: 12 Month

Index of insulin secretion, higher index means higher insulin secretion. C-peptide circulates in blood in amounts equal to insulin because insulin and C-peptide are linked when first made by the pancreas. C-peptide is more stable in blood than insulin; therefore it can be reliably used to evaluate insulin secretion. It is calculated by a special formula using C-peptide and glucose measured at 0 min and at 30 min (hence 30 in the name) in Oral Glucose Tolerance test. Insulin secretion was assessed based on formula C-Peptidogenic index-30 \[(C-Peptide at 30 min - fasting C-peptide)/(glucose at 30 min - fasting glucose)\]Bergstrom RW, Wahl PW, Leonetti DL, Fujimoto WY. Association of fasting glucose levels with a delayed secretion of insulin after oral glucose in subjects with glucose intolerance. J Clin Endocrinol Metab. 1990;71:1447-1453.)

Outcome measures

Outcome measures
Measure	Placebo n=86 Participants Supplement of vitamin D 400 units provided to all subjects in addition to Placebo.	50K Vitamin D2 n=87 Participants Supplement of vitamin D 400 units provided to all subjects in addition to D2 50K.
C-Peptidogenic Index-30	-0.64 (ng/mL)/(mg/dL) Standard Deviation 15.84	5.32 (ng/mL)/(mg/dL) Standard Deviation 17.47

SECONDARY outcome

Timeframe: 12 Months

Outcome measures

Outcome measures
Measure	Placebo n=86 Participants Supplement of vitamin D 400 units provided to all subjects in addition to Placebo.	50K Vitamin D2 n=87 Participants Supplement of vitamin D 400 units provided to all subjects in addition to D2 50K.
Incident Diabetes	9 participants	9 participants

POST_HOC outcome

Timeframe: 12 Months

Outcome measures

Outcome measures
Measure	Placebo n=86 Participants Supplement of vitamin D 400 units provided to all subjects in addition to Placebo.	50K Vitamin D2 n=87 Participants Supplement of vitamin D 400 units provided to all subjects in addition to D2 50K.
Change in Glycemia	8.3 percentage of participants	31.6 percentage of participants

Adverse Events

Placebo

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

50K Vitamin D2

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Barengolts, Attending Endocrinologist, Chief, Section of Endocrinology

Jesse Brown VA Medical Center

Phone: 312-569-7651

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place