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

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
 
ClinicalTrials.gov Identifier: NCT02416193
Recruitment Status : Completed
First Posted : April 14, 2015
Last Update Posted : September 28, 2018
Sponsor:
Collaborator:
University of Chicago
Information provided by (Responsible Party):
Mary A Byrn, Loyola University

Tracking Information
First Submitted Date  ICMJE April 6, 2015
First Posted Date  ICMJE April 14, 2015
Last Update Posted Date September 28, 2018
Actual Study Start Date  ICMJE April 2015
Actual Primary Completion Date July 12, 2018   (Final data collection date for primary outcome measure)
Current Primary Outcome Measures  ICMJE
 (submitted: April 9, 2015)
Cognitive functioning [ Time Frame: 13 weeks ]
Evaluate whether persons receiving weekly vitamin D3 supplementation (50,000 IUs) will have improved cognitive function as measured by a linear composite score on six cognitive functioning measures compared to those receiving the comparator (5000 IUs) at 13 weeks. The linear composite score will be calculated from performance on the following six cognitive functioning measures: (1) The Controlled Oral Word Association Test; (2) The Animal Naming Test; (3) The Letter Number Sequencing Test; (4) Stroop Interference Test; (5) Digit Symbol Modalities Test; and (6) Trail Making Test Parts A and B.
Original Primary Outcome Measures  ICMJE Same as current
Change History Complete list of historical versions of study NCT02416193 on ClinicalTrials.gov Archive Site
Current Secondary Outcome Measures  ICMJE
 (submitted: April 9, 2015)
Diabetes self-management [ Time Frame: 13 weeks ]
Will evaluate whether persons receiving weekly vitamin D3 supplementation (50,000 IUs) will have improved self-management as measured by a linear composite score on five functioning measures compared to those receiving the comparator (5000 IUs) at 13 weeks. The linear composite score will be calculated from performance on the following five functioning measures: (1) The Pittsburg Sleep Quality Index; (2) The Perceived Stressor Scale; (3) Social Adjustment Scale Self-Report; (4) Godin Leisure Time Exercise Questionnaire; and (5) Endicott Work Productivity Scale.
Original Secondary Outcome Measures  ICMJE Same as current
Current Other Pre-specified Outcome Measures Not Provided
Original Other Pre-specified Outcome Measures Not Provided
 
Descriptive Information
Brief Title  ICMJE Can Vitamin D3 Improve Cognitive Function in Individuals With Type 2 Diabetes? (THINK-D)
Official Title  ICMJE Can Vitamin D3 Improve Cognitive Function in Individuals With Type 2 Diabetes? (THINK-D)
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.

Study Type  ICMJE Interventional
Study Phase  ICMJE Phase 2
Study Design  ICMJE Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Condition  ICMJE
  • Diabetes
  • Executive Dysfunction
Intervention  ICMJE
  • Drug: Cholecalciferol
    Participants will take randomly assigned high dose cholecalciferol once weekly for three months
    Other Name: Vitamin D3
  • Drug: Cholecalciferol
    Participants will take randomly assigned active comparator cholecalciferol once weekly for three months
    Other Name: Vitamin D3
Study Arms  ICMJE
  • Experimental: High Dose
    50,000 IU cholecalciferol once weekly for three months
    Intervention: Drug: Cholecalciferol
  • Active Comparator: Low Dose
    5,000 IU cholecalciferol once weekly for three months
    Intervention: Drug: Cholecalciferol
Publications *

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Recruitment Information
Recruitment Status  ICMJE Completed
Actual Enrollment  ICMJE
 (submitted: September 27, 2018)
56
Original Estimated Enrollment  ICMJE
 (submitted: April 9, 2015)
80
Actual Study Completion Date  ICMJE July 12, 2018
Actual Primary Completion Date July 12, 2018   (Final data collection date for primary outcome measure)
Eligibility Criteria  ICMJE

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%
Sex/Gender  ICMJE
Sexes Eligible for Study: All
Ages  ICMJE 18 Years to 75 Years   (Adult, Older Adult)
Accepts Healthy Volunteers  ICMJE No
Contacts  ICMJE Contact information is only displayed when the study is recruiting subjects
Listed Location Countries  ICMJE United States
Removed Location Countries  
 
Administrative Information
NCT Number  ICMJE NCT02416193
Other Study ID Numbers  ICMJE 206988
206988031815 ( Other Identifier: Loyola University Chicago )
Has Data Monitoring Committee No
U.S. FDA-regulated Product Not Provided
IPD Sharing Statement  ICMJE Not Provided
Responsible Party Mary A Byrn, Loyola University
Study Sponsor  ICMJE Loyola University
Collaborators  ICMJE University of Chicago
Investigators  ICMJE
Principal Investigator: Mary A Byrn, Ph.D., R.N. Loyola University
PRS Account Loyola University
Verification Date September 2018

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP