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

Primary Purpose

Diabetes, Executive Dysfunction

Status
Terminated
Phase
Phase 2
Locations
United States
Study Type
Interventional
Intervention
Cholecalciferol
Cholecalciferol
Sponsored by
Loyola University
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional treatment trial for Diabetes focused on measuring Diabetes, Cognition, Functioning

Eligibility Criteria

18 Years - 75 Years (Adult, Older Adult)All SexesDoes not accept healthy volunteers

Inclusion Criteria:

  • Women and men aged 18 to 75 years
  • Have type 2 diabetes
  • Having a subjective complaint of a cognitive dysfunction or scoring at least one standard deviation below normal on a cognitive functioning screening test
  • Vitamin D level as measured by 25-hydroxyvitamin D (25-OH D) < 32 ng/mL
  • Under the care of a healthcare provider
  • Systolic blood pressure ≤160 and diastolic blood pressure ≤100

Exclusion Criteria:

  • Persons with malabsorption problems (e.g., crohn's disease)
  • Hypercalcemia
  • Supplementation other than a daily multivitamin
  • Severe complications of diabetes (i.e., amputation, blindness, and dialysis)
  • Concomitant use of steroids
  • GFR < 60
  • Creatinine > 1.2
  • Significant depressive symptoms
  • Having a history of bipolar depression, psychotic disorders, loss of consciousness greater than 5 minutes, or a current alcohol or substance use disorder
  • Other serious medical conditions deemed significant by the PI or medical monitor
  • Concomitant use of cholinesterase inhibitors
  • Concomitant use of anxiolytics, kava kava, St. John's Wort, or Ginkgo Biloba
  • Pregnancy
  • HbA1c >13%

Sites / Locations

  • Loyola University Medical Center

Arms of the Study

Arm 1

Arm 2

Arm Type

Experimental

Active Comparator

Arm Label

High Dose

Low Dose

Arm Description

50,000 IU cholecalciferol once weekly for three months

5,000 IU cholecalciferol once weekly for three months

Outcomes

Primary Outcome Measures

Letter-Number Sequencing
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.
Controlled Oral Word Association Test
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.
Stroop Interference Test
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.
Symbol-Digit Modality Test
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.
Trail Making Test Part B
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.

Secondary Outcome Measures

Hopkins Verbal Learning Total Recall Test
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.
Semantic Fluency Test
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.

Full Information

First Posted
April 6, 2015
Last Updated
September 30, 2020
Sponsor
Loyola University
Collaborators
University of Chicago
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1. Study Identification

Unique Protocol Identification Number
NCT02416193
Brief Title
Can Vitamin D3 Improve Cognitive Function in Individuals With Type 2 Diabetes? (THINK-D)
Acronym
THINK-D
Official Title
Can Vitamin D3 Improve Cognitive Function in Individuals With Type 2 Diabetes? (THINK-D)
Study Type
Interventional

2. Study Status

Record Verification Date
September 2020
Overall Recruitment Status
Terminated
Why Stopped
the study was halted prematurely due to slow recruitment and expiration of funding
Study Start Date
September 23, 2015 (Actual)
Primary Completion Date
July 12, 2018 (Actual)
Study Completion Date
July 12, 2018 (Actual)

3. Sponsor/Collaborators

Responsible Party, by Official Title
Principal Investigator
Name of the Sponsor
Loyola University
Collaborators
University of Chicago

4. Oversight

Studies a U.S. FDA-regulated Drug Product
Yes
Studies a U.S. FDA-regulated Device Product
No
Data Monitoring Committee
No

5. Study Description

Brief Summary
Diabetes increases the risk of cognitive dysfunction. The incidence of dementia is 1.5 to 2.5 times higher in persons with diabetes than the general population. There is evidence that cognitive decline significantly impacts the ability to self-manage diabetes. Strategies to prevent cognitive decline in persons with diabetes has not been well studied. A recent study reported that in persons who had vitamin D deficiency, the risk for all-cause dementia and Alzheimer's was doubled. Vitamin D receptors are located in the brain and deficiency of vitamin D has been reported to negatively affect the development of brain. Therefore, providing vitamin D supplementation to improve cognitive function is worthy of study. The investigators propose a small, randomized controlled trial to determine the effects of vitamin D3 supplementation in persons with type 2 diabetes who have symptoms of cognitive impairment. Persons will be randomized to receive either weekly vitamin D3 supplementation (50,000 IUs) or a matching comparator (5000 IUs) for a period of three months. The study aims are to determine (1) the effect of vitamin D3 supplementation on cognitive function and (2) the effect of vitamin D3 supplementation on diabetes self-management. A sample of persons with type 2 diabetes (n=62), who have a subjective complaint of a cognitive dysfunction or scoring at least one standard deviation below normal on a cognitive functioning screening test, have vitamin D levels less 30 ng/ml, are not depressed (as this impacts cognitive function), and do not have severe diabetes complication will be recruited. Participants will be phone screened and complete two baseline visits prior to randomization. They will then have phone call and follow-up visits to assess (1) cognitive function using standardized tests to assess for executive function (2) serum measurements (HBA1c, fasting glucose, vitamin D levels, and cardiometabolic profile) and (3) surveys to assess cognitive function as well as self-management behaviors.
Detailed Description
Study Aims Diabetes increases the risk of cognitive dysfunction. The incidence of dementia is 1.5 to 2.5 times higher in persons with diabetes than the general population (1). There is evidence that cognitive decline significantly impacts the ability to self-manage diabetes (2). Strategies to prevent cognitive decline in persons with diabetes has not been well studied. A recent study reported that in persons who had vitamin D deficiency, the risk for all-cause dementia and Alzheimer's was doubled (3). Vitamin D receptors are located in the brain, and deficiency of vitamin D has been reported to negatively affect the development of brain and impact both growth factor signaling and neural activity (4, 5). Therefore, providing vitamin D supplementation to improve cognitive function in persons with diabetes who are at great risk for this comorbid condition is important. The investigators propose a small, randomized controlled trial to determine the effects of vitamin D3 supplementation in persons with type 2 diabetes who have symptoms of cognitive impairment. Persons will be randomized to receive either weekly vitamin D3 supplementation (50,000 IUs) or a matching comparator (5000 IUs) for a period of three months. Primary Aim: To determine the effect of vitamin D3 supplementation on cognitive function for persons with type 2 diabetes. Primary Hypothesis: Persons receiving weekly vitamin D3 supplementation (50,000 IUs) will have improved cognitive function compared to those receiving the comparator (5000 IUs) at three months. Secondary Aim: To determine the effect of vitamin D3 supplementation on diabetes self-management. Secondary Hypothesis: Persons receiving weekly vitamin D3 supplementation (50,000 IUs) will have improved self-management compared to those receiving the comparator (5000 IUs) at three months. The importance of this study is several fold. Vitamin D supplementation is a low cost intervention (6), it has minimal side effects (7), and it could have high impact for persons with type 2 diabetes who suffer from cognitive impairment which can significantly affect their diabetes self-management.

6. Conditions and Keywords

Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
Diabetes, Executive Dysfunction
Keywords
Diabetes, Cognition, Functioning

7. Study Design

Primary Purpose
Treatment
Study Phase
Phase 2
Interventional Study Model
Parallel Assignment
Masking
ParticipantCare ProviderInvestigatorOutcomes Assessor
Allocation
Randomized
Enrollment
56 (Actual)

8. Arms, Groups, and Interventions

Arm Title
High Dose
Arm Type
Experimental
Arm Description
50,000 IU cholecalciferol once weekly for three months
Arm Title
Low Dose
Arm Type
Active Comparator
Arm Description
5,000 IU cholecalciferol once weekly for three months
Intervention Type
Drug
Intervention Name(s)
Cholecalciferol
Other Intervention Name(s)
Vitamin D3
Intervention Description
Participants will take randomly assigned high dose cholecalciferol once weekly for three months
Intervention Type
Drug
Intervention Name(s)
Cholecalciferol
Other Intervention Name(s)
Vitamin D3
Intervention Description
Participants will take randomly assigned active comparator cholecalciferol once weekly for three months
Primary Outcome Measure Information:
Title
Letter-Number Sequencing
Description
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.
Time Frame
13 weeks
Title
Controlled Oral Word Association Test
Description
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.
Time Frame
13 Weeks
Title
Stroop Interference Test
Description
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.
Time Frame
13 Weeks
Title
Symbol-Digit Modality Test
Description
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.
Time Frame
13 Weeks
Title
Trail Making Test Part B
Description
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.
Time Frame
13 Weeks
Secondary Outcome Measure Information:
Title
Hopkins Verbal Learning Total Recall Test
Description
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.
Time Frame
13 weeks
Title
Semantic Fluency Test
Description
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.
Time Frame
13 Weeks

10. Eligibility

Sex
All
Minimum Age & Unit of Time
18 Years
Maximum Age & Unit of Time
75 Years
Accepts Healthy Volunteers
No
Eligibility Criteria
Inclusion Criteria: Women and men aged 18 to 75 years Have type 2 diabetes Having a subjective complaint of a cognitive dysfunction or scoring at least one standard deviation below normal on a cognitive functioning screening test Vitamin D level as measured by 25-hydroxyvitamin D (25-OH D) < 32 ng/mL Under the care of a healthcare provider Systolic blood pressure ≤160 and diastolic blood pressure ≤100 Exclusion Criteria: Persons with malabsorption problems (e.g., crohn's disease) Hypercalcemia Supplementation other than a daily multivitamin Severe complications of diabetes (i.e., amputation, blindness, and dialysis) Concomitant use of steroids GFR < 60 Creatinine > 1.2 Significant depressive symptoms Having a history of bipolar depression, psychotic disorders, loss of consciousness greater than 5 minutes, or a current alcohol or substance use disorder Other serious medical conditions deemed significant by the PI or medical monitor Concomitant use of cholinesterase inhibitors Concomitant use of anxiolytics, kava kava, St. John's Wort, or Ginkgo Biloba Pregnancy HbA1c >13%
Overall Study Officials:
First Name & Middle Initial & Last Name & Degree
Mary A Byrn, Ph.D., R.N.
Organizational Affiliation
Loyola University
Official's Role
Principal Investigator
Facility Information:
Facility Name
Loyola University Medical Center
City
Maywood
State/Province
Illinois
ZIP/Postal Code
60153
Country
United States

12. IPD Sharing Statement

Plan to Share IPD
No
IPD Sharing Plan Description
There is no plan to share individual participant data with other researchers
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