Trial Outcomes & Findings for Can Vitamin D3 Improve Cognitive Function in Individuals With Type 2 Diabetes? (THINK-D) (NCT NCT02416193)

NCT ID: NCT02416193

Last Updated: 2020-10-23

Results Overview

The the Letter-Number Sequencing Test (from the Wechsler Adult Intelligence Scale-III assessment) is an assessment of working memory. Scores on the assessment are standardized as scaled scores with a mean of 10 and standard deviation of 3 (μ = 10, SD = 3) using age adjusted normative data provided by Pearson assessments (https://www.pearsonassessments.com/). A scaled score indicates the number of standard deviations away from the mean. A scaled score of 10 is equal to the mean. Scaled scores below 10 indicate performance is lower than average, and scaled scores higher than 10 indicate performance is higher than average. Higher scaled scores indicate better performance.

Recruitment status

TERMINATED

Study phase

PHASE2

Target enrollment

56 participants

Primary outcome timeframe

13 weeks

Results posted on

2020-10-23

Participant Flow

Recruitment for this study took place at Loyola University Medical Center (Maywood, IL) between September 2015 and June 2018

Fifty-six participants consented to participate in the study. Among these individuals, 26 (46.43%) were not randomized and were excluded from continuing their participation in the study because the medical monitor determined they did not meet study inclusion criteria.

Participant milestones

Participant milestones
Measure
Low Dose
5,000 IU cholecalciferol once weekly for three months
High Dose
50,000 IU cholecalciferol once weekly for three months
Overall Study
STARTED
15
15
Overall Study
COMPLETED
15
15
Overall Study
NOT COMPLETED
0
0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Can Vitamin D3 Improve Cognitive Function in Individuals With Type 2 Diabetes? (THINK-D)

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Low Dose
n=15 Participants
5,000 IU cholecalciferol once weekly for three months
High Dose
n=15 Participants
50,000 IU cholecalciferol once weekly for three months
Total
n=30 Participants
Total of all reporting groups
Age, Continuous
55.62 years
STANDARD_DEVIATION 10.14 • n=5 Participants
55.80 years
STANDARD_DEVIATION 9.68 • n=7 Participants
55.71 years
STANDARD_DEVIATION 9.74 • n=5 Participants
Sex: Female, Male
Female
14 Participants
n=5 Participants
11 Participants
n=7 Participants
25 Participants
n=5 Participants
Sex: Female, Male
Male
1 Participants
n=5 Participants
4 Participants
n=7 Participants
5 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
4 Participants
n=5 Participants
2 Participants
n=7 Participants
6 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
10 Participants
n=5 Participants
13 Participants
n=7 Participants
23 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
1 Participants
n=5 Participants
0 Participants
n=7 Participants
1 Participants
n=5 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
Race (NIH/OMB)
Asian
0 Participants
n=5 Participants
1 Participants
n=7 Participants
1 Participants
n=5 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
1 Participants
n=5 Participants
0 Participants
n=7 Participants
1 Participants
n=5 Participants
Race (NIH/OMB)
Black or African American
8 Participants
n=5 Participants
9 Participants
n=7 Participants
17 Participants
n=5 Participants
Race (NIH/OMB)
White
5 Participants
n=5 Participants
4 Participants
n=7 Participants
9 Participants
n=5 Participants
Race (NIH/OMB)
More than one race
1 Participants
n=5 Participants
1 Participants
n=7 Participants
2 Participants
n=5 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
Region of Enrollment
United States
15 participants
n=5 Participants
15 participants
n=7 Participants
30 participants
n=5 Participants
Years of education
14 years
n=5 Participants
14 years
n=7 Participants
14 years
n=5 Participants
Total vitamin D level
21 Nanograms per milliliter (ng/mL)
n=5 Participants
25 Nanograms per milliliter (ng/mL)
n=7 Participants
24 Nanograms per milliliter (ng/mL)
n=5 Participants
Serum vitamin D3 level
21 Nanograms per milliliter (ng/mL)
n=5 Participants
24 Nanograms per milliliter (ng/mL)
n=7 Participants
22 Nanograms per milliliter (ng/mL)
n=5 Participants
Body mass index
40.44 kilograms per meter squared (kg/m^2)
STANDARD_DEVIATION 9.48 • n=5 Participants
34.20 kilograms per meter squared (kg/m^2)
STANDARD_DEVIATION 5.05 • n=7 Participants
37.32 kilograms per meter squared (kg/m^2)
STANDARD_DEVIATION 8.11 • n=5 Participants
Martial status
Currently married
10 Participants
n=5 Participants
4 Participants
n=7 Participants
14 Participants
n=5 Participants
Martial status
Separated
0 Participants
n=5 Participants
1 Participants
n=7 Participants
1 Participants
n=5 Participants
Martial status
Widowed
2 Participants
n=5 Participants
0 Participants
n=7 Participants
2 Participants
n=5 Participants
Martial status
Divorced
2 Participants
n=5 Participants
5 Participants
n=7 Participants
7 Participants
n=5 Participants
Martial status
Never married
1 Participants
n=5 Participants
5 Participants
n=7 Participants
6 Participants
n=5 Participants
Season of first dose of the study drug
Fall
5 Participants
n=5 Participants
5 Participants
n=7 Participants
10 Participants
n=5 Participants
Season of first dose of the study drug
Winter
3 Participants
n=5 Participants
6 Participants
n=7 Participants
9 Participants
n=5 Participants
Season of first dose of the study drug
Spring
5 Participants
n=5 Participants
1 Participants
n=7 Participants
6 Participants
n=5 Participants
Season of first dose of the study drug
Summer
2 Participants
n=5 Participants
3 Participants
n=7 Participants
5 Participants
n=5 Participants
Systolic blood pressure
134.73 Millimeters of mercury (mmHg)
STANDARD_DEVIATION 16.33 • n=5 Participants
131.13 Millimeters of mercury (mmHg)
STANDARD_DEVIATION 16.95 • n=7 Participants
132.93 Millimeters of mercury (mmHg)
STANDARD_DEVIATION 16.45 • n=5 Participants
Diastolic blood pressure
73.47 Millimeters of mercury (mmHg)
STANDARD_DEVIATION 10.99 • n=5 Participants
72.93 Millimeters of mercury (mmHg)
STANDARD_DEVIATION 10.79 • n=7 Participants
73.20 Millimeters of mercury (mmHg)
STANDARD_DEVIATION 10.70 • n=5 Participants
Heart rate
73.27 Beats per minute (BPM)
STANDARD_DEVIATION 12.67 • n=5 Participants
76.00 Beats per minute (BPM)
STANDARD_DEVIATION 12.86 • n=7 Participants
74.63 Beats per minute (BPM)
STANDARD_DEVIATION 12.62 • n=5 Participants
HbA1c
7.10 mmol/mol
n=5 Participants
7.20 mmol/mol
n=7 Participants
7.15 mmol/mol
n=5 Participants
Glucose
120 Millimoles per liter (mmol/L)
n=5 Participants
142 Millimoles per liter (mmol/L)
n=7 Participants
134 Millimoles per liter (mmol/L)
n=5 Participants
Calcium
9.40 milligrams per deciliter (mg/dL)
n=5 Participants
9.60 milligrams per deciliter (mg/dL)
n=7 Participants
9.50 milligrams per deciliter (mg/dL)
n=5 Participants
Creatinine
0.74 milligrams per deciliter (mg/dL)
n=5 Participants
0.83 milligrams per deciliter (mg/dL)
n=7 Participants
0.79 milligrams per deciliter (mg/dL)
n=5 Participants
Activity level
Insufficiently active
5 Participants
n=5 Participants
6 Participants
n=7 Participants
11 Participants
n=5 Participants
Activity level
Moderately active
3 Participants
n=5 Participants
3 Participants
n=7 Participants
6 Participants
n=5 Participants
Activity level
Sufficiently active
7 Participants
n=5 Participants
6 Participants
n=7 Participants
13 Participants
n=5 Participants
WRAT-IV Reading Score
-1.00 units on a scale
n=5 Participants
-0.93 units on a scale
n=7 Participants
-0.97 units on a scale
n=5 Participants
Patient Health Questionnaire-9
2 units on a scale
n=5 Participants
4 units on a scale
n=7 Participants
3 units on a scale
n=5 Participants
CES-D Score
7.13 units on a scale
STANDARD_DEVIATION 3.46 • n=5 Participants
9.73 units on a scale
STANDARD_DEVIATION 4.80 • n=7 Participants
8.43 units on a scale
STANDARD_DEVIATION 4.32 • n=5 Participants

PRIMARY outcome

Timeframe: 13 weeks

Population: The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug.

The the Letter-Number Sequencing Test (from the Wechsler Adult Intelligence Scale-III assessment) is an assessment of working memory. Scores on the assessment are standardized as scaled scores with a mean of 10 and standard deviation of 3 (μ = 10, SD = 3) using age adjusted normative data provided by Pearson assessments (https://www.pearsonassessments.com/). A scaled score indicates the number of standard deviations away from the mean. A scaled score of 10 is equal to the mean. Scaled scores below 10 indicate performance is lower than average, and scaled scores higher than 10 indicate performance is higher than average. Higher scaled scores indicate better performance.

Outcome measures

Outcome measures
Measure
Low Dose
n=15 Participants
5,000 IU cholecalciferol once weekly for three months
High Dose
n=15 Participants
50,000 IU cholecalciferol once weekly for three months
Letter-Number Sequencing
9.13 units on a scale
Standard Deviation 2.53
9.00 units on a scale
Standard Deviation 1.87

PRIMARY outcome

Timeframe: 13 Weeks

Population: The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug.

The Controlled Oral Word Association Test is a measure of verbal fluency. Scores are standardized as z-scores (μ = 0, SD = 1) using age adjusted normative data provided by Tombaugh and Kozak (1996). A z-score indicates the number of standard deviations away from the mean. A z-score of 0 is equal to the mean. Negative z-scores indicate performance is lower than average, and positive z-scores indicate performance is higher than average. Positive z-scores indicate better performance.

Outcome measures

Outcome measures
Measure
Low Dose
n=15 Participants
5,000 IU cholecalciferol once weekly for three months
High Dose
n=15 Participants
50,000 IU cholecalciferol once weekly for three months
Controlled Oral Word Association Test
-0.35 units on a scale
Standard Deviation 1.10
-0.37 units on a scale
Standard Deviation 0.93

PRIMARY outcome

Timeframe: 13 Weeks

Population: The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug.

The Stroop Interference Test is a measure of executive functioning. Scores are standardized as z-scores (μ = 0, SD = 1) using age adjusted normative data provided by PAR Incorporated (https://www.parinc.com/). A z-score indicates the number of standard deviations away from the mean. A z-score of 0 is equal to the mean. Negative z-scores indicate performance is lower than average, and positive z-scores indicate performance is higher than average. Positive z-scores indicate better performance.

Outcome measures

Outcome measures
Measure
Low Dose
n=15 Participants
5,000 IU cholecalciferol once weekly for three months
High Dose
n=15 Participants
50,000 IU cholecalciferol once weekly for three months
Stroop Interference Test
-0.15 units on a scale
Standard Deviation 0.88
-0.30 units on a scale
Standard Deviation 0.96

PRIMARY outcome

Timeframe: 13 Weeks

Population: The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug.

The Symbol-Digit Modality Test is a measure of executive functioning. Scores are standardized as z-scores (μ = 0, SD = 1) using age adjusted normative data provided by WPS Publishers (https://www.wpspublish.com/). A z-score indicates the number of standard deviations away from the mean. A z-score of 0 is equal to the mean. Negative z-scores indicate performance is lower than average, and positive z-scores indicate performance is higher than average. Positive z-scores indicate better performance.

Outcome measures

Outcome measures
Measure
Low Dose
n=15 Participants
5,000 IU cholecalciferol once weekly for three months
High Dose
n=15 Participants
50,000 IU cholecalciferol once weekly for three months
Symbol-Digit Modality Test
0.12 units on a scale
Standard Deviation 0.82
0.05 units on a scale
Standard Deviation 1.20

PRIMARY outcome

Timeframe: 13 Weeks

Population: The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug.

The Trail Making Test Part B is a measure of executive functioning. Scores are standardized as z-scores (μ = 0, SD = 1) using age adjusted normative data provided by WPS Publishers (https://www.wpspublish.com/). A z-score indicates the number of standard deviations away from the mean. A z-score of 0 is equal to the mean. Negative z-scores indicate performance is lower than average, and positive z-scores indicate performance is higher than average. Positive z-scores indicate better performance.

Outcome measures

Outcome measures
Measure
Low Dose
n=15 Participants
5,000 IU cholecalciferol once weekly for three months
High Dose
n=15 Participants
50,000 IU cholecalciferol once weekly for three months
Trail Making Test Part B
0.01 units on a scale
Standard Deviation 0.85
-0.10 units on a scale
Standard Deviation 1.35

SECONDARY outcome

Timeframe: 13 weeks

Population: The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug.

The Hopkins Verbal Learning Total Recall Test is an assessment of memory. Scores are standardized as T-scores (μ = 50, SD = 10) using age adjusted normative data provided by PAR Incorporated (https://www.parinc.com/). A T-score indicates the number of standard deviations away from the mean. A T-score of 50 is equal to the mean. T-scores below 50 indicate performance is lower than average, and T-scores above 50 indicate performance is higher than average. Higher T-scores indicate better performance.

Outcome measures

Outcome measures
Measure
Low Dose
n=15 Participants
5,000 IU cholecalciferol once weekly for three months
High Dose
n=15 Participants
50,000 IU cholecalciferol once weekly for three months
Hopkins Verbal Learning Total Recall Test
38.07 units on a scale
Standard Deviation 8.92
39.57 units on a scale
Standard Deviation 11.50

SECONDARY outcome

Timeframe: 13 Weeks

Population: The analysis population comprises all individuals who signed an informed consent document and took at least one dose of the study drug.

The Semantic Fluency Test is a measure of verbal fluency. Scores are standardized as z-scores (μ = 0, SD = 1) using age adjusted normative data provided by Tombaugh and Kozak (1996). A z-score indicates the number of standard deviations away from the mean. A z-score of 0 is equal to the mean. Negative z-scores indicate performance is lower than average, and positive z-scores indicate performance is higher than average. Positive z-scores indicate better performance.

Outcome measures

Outcome measures
Measure
Low Dose
n=15 Participants
5,000 IU cholecalciferol once weekly for three months
High Dose
n=15 Participants
50,000 IU cholecalciferol once weekly for three months
Semantic Fluency Test
0.41 units on a scale
Standard Deviation 1.46
-0.36 units on a scale
Standard Deviation 0.95

Adverse Events

Low Dose

Serious events: 0 serious events
Other events: 12 other events
Deaths: 0 deaths

High Dose

Serious events: 1 serious events
Other events: 9 other events
Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure
Low Dose
n=15 participants at risk
5,000 IU cholecalciferol once weekly for three months
High Dose
n=15 participants at risk
50,000 IU cholecalciferol once weekly for three months
Nervous system disorders
Stroke
0.00%
0/15 • Adverse event data were collected for 20 weeks
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks

Other adverse events

Other adverse events
Measure
Low Dose
n=15 participants at risk
5,000 IU cholecalciferol once weekly for three months
High Dose
n=15 participants at risk
50,000 IU cholecalciferol once weekly for three months
Infections and infestations
Cold virus
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
26.7%
4/15 • Number of events 4 • Adverse event data were collected for 20 weeks
Reproductive system and breast disorders
Short menstrual period
7.1%
1/14 • Number of events 1 • Adverse event data were collected for 20 weeks
0.00%
0/11 • Adverse event data were collected for 20 weeks
Reproductive system and breast disorders
Menstrual cramps
0.00%
0/14 • Adverse event data were collected for 20 weeks
9.1%
1/11 • Number of events 2 • Adverse event data were collected for 20 weeks
General disorders
Arm pain
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
General disorders
Toothache
0.00%
0/15 • Adverse event data were collected for 20 weeks
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
General disorders
Nausea
20.0%
3/15 • Number of events 3 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
Gastrointestinal disorders
Constipation
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
Eye disorders
Cataracts
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
Endocrine disorders
Hypercalcemia
0.00%
0/15 • Adverse event data were collected for 20 weeks
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
Renal and urinary disorders
Hemorrhoids
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
General disorders
Poor appetite
0.00%
0/15 • Adverse event data were collected for 20 weeks
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
Gastrointestinal disorders
Dark stools
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
Respiratory, thoracic and mediastinal disorders
Asthma
0.00%
0/15 • Adverse event data were collected for 20 weeks
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
Infections and infestations
Sinus infection
0.00%
0/15 • Adverse event data were collected for 20 weeks
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
Infections and infestations
Strep throat
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
General disorders
Sore throat
6.7%
1/15 • Number of events 3 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
Nervous system disorders
Fall
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
General disorders
Tiredness
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
General disorders
Muscle aches
0.00%
0/15 • Adverse event data were collected for 20 weeks
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
Endocrine disorders
Goiter
0.00%
0/15 • Adverse event data were collected for 20 weeks
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
General disorders
Arhritis
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
General disorders
Foot pain
13.3%
2/15 • Number of events 2 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
General disorders
Restlessness
0.00%
0/15 • Adverse event data were collected for 20 weeks
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
General disorders
Shoulder pain
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
Skin and subcutaneous tissue disorders
Knee cyst
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
General disorders
Leg cramps
13.3%
2/15 • Number of events 2 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
Social circumstances
Motor vehicle accident
6.7%
1/15 • Number of events 1 • Adverse event data were collected for 20 weeks
0.00%
0/15 • Adverse event data were collected for 20 weeks
Cardiac disorders
Hypertension
0.00%
0/15 • Adverse event data were collected for 20 weeks
13.3%
2/15 • Number of events 2 • Adverse event data were collected for 20 weeks

Additional Information

Mary Byrn, R.N., Ph.D.

Loyola University Chicago

Phone: (773) 508-8973

Results disclosure agreements

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