DiabetesPhase 2THINK-DNCT02416193
Can Vitamin D3 Improve Cognitive Function in Individuals With Type 2 Diabetes? (THINK-D)
A Phase 2 study testing Cholecalciferol in people with Diabetes and Executive Dysfunction, run by Loyola University at 1 site in United States.
Trial 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. Read more about this study
- Who is it for?
- Ages 18 to 75 years
- Conditions the study is for
- Diabetes, Executive Dysfunction
- What is being tested?
- Cholecalciferol
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 56 participants
- Where
- 1 siteUnited States
- Study dates
- 23 Sep 2015to 12 Jul 2018
- Phase
- Phase 2
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 75 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 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
Who cannot join
- 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
Show all 14Show fewer
- 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%
Trial locations and contacts
1 site in 1 country.
United States1 site
Loyola University Medical Center
Maywood, Illinois, 60153
About this study
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.
Read the 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.
- Conditions
- Diabetes, Executive Dysfunction
- Being tested
- Cholecalciferol
- Keywords
- Diabetes, Cognition, Functioning
- Medical subject headings
- Diabetes Mellitus
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CholecalciferolDrug
Also called Vitamin D3
Participants will take randomly assigned high dose cholecalciferol once weekly for three months
CholecalciferolDrug
Also called Vitamin D3
Participants will take randomly assigned active comparator cholecalciferol once weekly for three months
| Study group | Role | What they receive |
|---|---|---|
| High Dose | Experimental | 50,000 IU cholecalciferol once weekly for three months Receives: Drug: Cholecalciferol |
| Low Dose | Active comparator | 5,000 IU cholecalciferol once weekly for three months Receives: Drug: Cholecalciferol |
What is being measured
The primary outcome is the main question the study is designed to answer.
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.
Measured: 13 weeks
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.
Measured: 13 Weeks
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.
Measured: 13 Weeks
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.
Measured: 13 Weeks
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.
Measured: 13 Weeks
Secondary outcomes (2)
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.
Measured: 13 weeks
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.
Measured: 13 Weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted14 Apr 2015 (estimated)
- Study start23 Sep 2015
- Primary completion12 Jul 2018
- Study completion12 Jul 2018
Why it stopped: the study was halted prematurely due to slow recruitment and expiration of funding
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (40)Papers the sponsor has linked to this study.
- Other trials for DiabetesStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 56 participants (actual)
Sponsor and investigators
- Lead sponsor
- Loyola University
- Sponsor type
- University, hospital or other
- Collaborators
- University of Chicago
- Responsible party
- Principal investigator, Mary A Byrn, Loyola University
- Investigators
- Mary A Byrn, Ph.D., R.N., Principal investigator, Loyola University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT02416193
- Sponsor's protocol ID
- 206988
- Other IDs
- 206988031815
- Acronym
- THINK-D
- Status last verified
- Sep 2020
- First submitted
- 6 Apr 2015
- Last updated
- 23 Oct 2020
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No: There is no plan to share individual participant data with other researchers
Publications
Lee JH, Choi Y, Jun C, Hong YS, Cho HB, Kim JE, Lyoo IK. Neurocognitive changes and their neural correlates in patients with type 2 diabetes mellitus. Endocrinol Metab (Seoul). 2014 Jun;29(2):112-21. doi: 10.3803/EnM.2014.29.2.112.
PubMed 25031883Smith MA, Else JE, Paul L, Foster JK, Walker M, Wesnes KA, Riby LM. Functional Living in Older Adults With Type 2 Diabetes: Executive Functioning, Dual Task Performance, and the Impact on Postural Stability and Motor Control. J Aging Health. 2014 Aug;26(5):841-859. doi: 10.1177/0898264314534896. Epub 2014 Jun 4.
PubMed 24898849Littlejohns TJ, Henley WE, Lang IA, Annweiler C, Beauchet O, Chaves PH, Fried L, Kestenbaum BR, Kuller LH, Langa KM, Lopez OL, Kos K, Soni M, Llewellyn DJ. Vitamin D and the risk of dementia and Alzheimer disease. Neurology. 2014 Sep 2;83(10):920-8. doi: 10.1212/WNL.0000000000000755. Epub 2014 Aug 6.
PubMed 25098535McCann JC, Ames BN. Is there convincing biological or behavioral evidence linking vitamin D deficiency to brain dysfunction? FASEB J. 2008 Apr;22(4):982-1001. doi: 10.1096/fj.07-9326rev. Epub 2007 Dec 4.
PubMed 18056830Schlogl M, Holick MF. Vitamin D and neurocognitive function. Clin Interv Aging. 2014 Apr 2;9:559-68. doi: 10.2147/CIA.S51785. eCollection 2014.
PubMed 24729696Holick MF. High prevalence of vitamin D inadequacy and implications for health. Mayo Clin Proc. 2006 Mar;81(3):353-73. doi: 10.4065/81.3.353.
PubMed 16529140Holick MF. Vitamin D deficiency. N Engl J Med. 2007 Jul 19;357(3):266-81. doi: 10.1056/NEJMra070553. No abstract available.
PubMed 17634462Tuligenga RH, Dugravot A, Tabak AG, Elbaz A, Brunner EJ, Kivimaki M, Singh-Manoux A. Midlife type 2 diabetes and poor glycaemic control as risk factors for cognitive decline in early old age: a post-hoc analysis of the Whitehall II cohort study. Lancet Diabetes Endocrinol. 2014 Mar;2(3):228-35. doi: 10.1016/S2213-8587(13)70192-X. Epub 2013 Dec 19.
PubMed 24622753Wennberg AMV, Gottesman RF, Kaufmann CN, Albert MS, Chen-Edinboro LP, Rebok GW, Kasper JD, Spira AP. Diabetes and cognitive outcomes in a nationally representative sample: the National Health and Aging Trends Study. Int Psychogeriatr. 2014 Oct;26(10):1729-1735. doi: 10.1017/S1041610214001380. Epub 2014 Jul 30.
PubMed 25075535Munshi MN, Hayes M, Iwata I, Lee Y, Weinger K. Which aspects of executive dysfunction influence ability to manage diabetes in older adults? Diabet Med. 2012 Sep;29(9):1171-7. doi: 10.1111/j.1464-5491.2012.03606.x.
PubMed 22340082Grober E, Hall CB, Hahn SR, Lipton RB. Memory Impairment and Executive Dysfunction are Associated with Inadequately Controlled Diabetes in Older Adults. J Prim Care Community Health. 2011 Oct 1;2(4):229-33. doi: 10.1177/2150131911409945. Epub 2011 Jun 1.
PubMed 23804840Retracted: Executive dysfunction in elderly diabetic patients. Geriatr Gerontol Int. 2015 Aug;15(8):1106. doi: 10.1111/ggi.12288. Epub 2014 Apr 21. No abstract available.
PubMed 24750335Winkler A, Dlugaj M, Weimar C, Jockel KH, Erbel R, Dragano N, Moebus S. Association of diabetes mellitus and mild cognitive impairment in middle-aged men and women. J Alzheimers Dis. 2014;42(4):1269-77. doi: 10.3233/JAD-140696.
PubMed 25024326Geijselaers SLC, Sep SJS, Stehouwer CDA, Biessels GJ. Glucose regulation, cognition, and brain MRI in type 2 diabetes: a systematic review. Lancet Diabetes Endocrinol. 2015 Jan;3(1):75-89. doi: 10.1016/S2213-8587(14)70148-2. Epub 2014 Aug 24.
PubMed 25163604Annweiler C, Montero-Odasso M, Llewellyn DJ, Richard-Devantoy S, Duque G, Beauchet O. Meta-analysis of memory and executive dysfunctions in relation to vitamin D. J Alzheimers Dis. 2013;37(1):147-71. doi: 10.3233/JAD-130452.
PubMed 23948884
Study at a glance
From the registry record, last updated by the sponsor on 23 Oct 2020. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Can Vitamin D3 Improve Cognitive Function in Individuals With Type 2 Diabetes? (THINK-D)
- ClinicalTrials.gov ID
- NCT02416193
- Acronym / sponsor ID
- THINK-D / 206988
- Conditions
- Diabetes, Executive Dysfunction
- Keywords
- Diabetes, Cognition, Functioning
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- TerminatedReason stopped: the study was halted prematurely due to slow recruitment and expiration of funding
- Enrolment
- 56 participants (actual)
- Lead sponsor
- Loyola UniversityUniversity, hospital or other
- Collaborators
- University of Chicago
- Study start
- 23 Sep 2015 (actual)
- Primary completion
- 12 Jul 2018 (actual)
- Study completion
- 12 Jul 2018 (actual)
- First posted
- 14 Apr 2015 (estimated)
- Results
- Posted 23 Oct 2020
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
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 design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| High Dose | Experimental | Drug: Cholecalciferol50,000 IU cholecalciferol once weekly for three months |
| Low Dose | Active comparator | Drug: Cholecalciferol5,000 IU cholecalciferol once weekly for three months |
Who may qualify
- Ages
- 18 to 75 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- 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
Key exclusion criteria (14 listed)
- 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
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| CholecalciferolAlso: Vitamin D3Participants will take randomly assigned high dose cholecalciferol once weekly for three months | Drug | High Dose |
| CholecalciferolAlso: Vitamin D3Participants will take randomly assigned active comparator cholecalciferol once weekly for three months | Drug | Low Dose |
Primary outcome
Letter-Number Sequencing
Time frame: 13 weeks
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
Time frame: 13 Weeks
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
Time frame: 13 Weeks
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
Time frame: 13 Weeks
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
Time frame: 13 Weeks
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.
2 secondary outcomes
Hopkins Verbal Learning Total Recall Test
Time frame: 13 weeks
Semantic Fluency Test
Time frame: 13 Weeks
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 23 Oct 2020.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Background: PubMed 25031883Lee JH, Choi Y, Jun C, Hong YS, Cho HB, Kim JE, Lyoo IK. Neurocognitive changes and their neural correlates in patients with type 2 diabetes mellitus. Endocrinol Metab (Seoul). 2014 Jun;29(2):112-21. doi: 10.3803/EnM.2014.29.2.112.
- Background: PubMed 24898849Smith MA, Else JE, Paul L, Foster JK, Walker M, Wesnes KA, Riby LM. Functional Living in Older Adults With Type 2 Diabetes: Executive Functioning, Dual Task Performance, and the Impact on Postural Stability and Motor Control. J Aging Health. 2014 Aug;26(5):841-859. doi: 10.1177/0898264314534896. Epub 2014 Jun 4.
- Background: PubMed 25098535Littlejohns TJ, Henley WE, Lang IA, Annweiler C, Beauchet O, Chaves PH, Fried L, Kestenbaum BR, Kuller LH, Langa KM, Lopez OL, Kos K, Soni M, Llewellyn DJ. Vitamin D and the risk of dementia and Alzheimer disease. Neurology. 2014 Sep 2;83(10):920-8. doi: 10.1212/WNL.0000000000000755. Epub 2014 Aug 6.
- Background: PubMed 18056830McCann JC, Ames BN. Is there convincing biological or behavioral evidence linking vitamin D deficiency to brain dysfunction? FASEB J. 2008 Apr;22(4):982-1001. doi: 10.1096/fj.07-9326rev. Epub 2007 Dec 4.
- Background: PubMed 24729696Schlogl M, Holick MF. Vitamin D and neurocognitive function. Clin Interv Aging. 2014 Apr 2;9:559-68. doi: 10.2147/CIA.S51785. eCollection 2014.
- Background: PubMed 16529140Holick MF. High prevalence of vitamin D inadequacy and implications for health. Mayo Clin Proc. 2006 Mar;81(3):353-73. doi: 10.4065/81.3.353.
- Background: PubMed 17634462Holick MF. Vitamin D deficiency. N Engl J Med. 2007 Jul 19;357(3):266-81. doi: 10.1056/NEJMra070553. No abstract available.
- Background: PubMed 24622753Tuligenga RH, Dugravot A, Tabak AG, Elbaz A, Brunner EJ, Kivimaki M, Singh-Manoux A. Midlife type 2 diabetes and poor glycaemic control as risk factors for cognitive decline in early old age: a post-hoc analysis of the Whitehall II cohort study. Lancet Diabetes Endocrinol. 2014 Mar;2(3):228-35. doi: 10.1016/S2213-8587(13)70192-X. Epub 2013 Dec 19.
- Background: PubMed 25075535Wennberg AMV, Gottesman RF, Kaufmann CN, Albert MS, Chen-Edinboro LP, Rebok GW, Kasper JD, Spira AP. Diabetes and cognitive outcomes in a nationally representative sample: the National Health and Aging Trends Study. Int Psychogeriatr. 2014 Oct;26(10):1729-1735. doi: 10.1017/S1041610214001380. Epub 2014 Jul 30.
- Background: PubMed 22340082Munshi MN, Hayes M, Iwata I, Lee Y, Weinger K. Which aspects of executive dysfunction influence ability to manage diabetes in older adults? Diabet Med. 2012 Sep;29(9):1171-7. doi: 10.1111/j.1464-5491.2012.03606.x.
- Background: PubMed 23804840Grober E, Hall CB, Hahn SR, Lipton RB. Memory Impairment and Executive Dysfunction are Associated with Inadequately Controlled Diabetes in Older Adults. J Prim Care Community Health. 2011 Oct 1;2(4):229-33. doi: 10.1177/2150131911409945. Epub 2011 Jun 1.
- Background: PubMed 24750335Retracted: Executive dysfunction in elderly diabetic patients. Geriatr Gerontol Int. 2015 Aug;15(8):1106. doi: 10.1111/ggi.12288. Epub 2014 Apr 21. No abstract available.
- Individual participant dataSharing planned: No. There is no plan to share individual participant data with other researchers
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Mary A Byrn, Ph.D., R.N. principal investigator
Loyola University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Cholecalciferol in people with Diabetes and Executive Dysfunction, run by Loyola University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 14 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: stopped early, as of the sponsor's last update on 23 Oct 2020. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 23 Oct 2020). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Letter-Number Sequencing (time frame: 13 weeks). The study lists 5 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT02416193, which also lists 40 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 23 Oct 2020; AzTrials last refreshed its copy on 29 Oct 2026.