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Trial registered on ANZCTR


Registration number
ACTRN12615001140549
Ethics application status
Approved
Date submitted
13/10/2015
Date registered
27/10/2015
Date last updated
3/10/2017
Type of registration
Prospectively registered

Titles & IDs
Public title
Correlation between Plasma Vitamin C Levels and Cognition: A Cross-Sectional Study
Scientific title
Correlation between Plasma Vitamin C Levels and Cognition in healthy adults.
Title was changed as a result of only healthy aduts being recruited. Surgery patients will be recruited in another trial, down the track. This was changed very early in the present trial when it was agreed that surgery patients will be recruited for a seperate trial.
Secondary ID [1] 287614 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Brain Health 296414 0
Cognition 296560 0
Condition category
Condition code
Neurological 296680 296680 0 0
Studies of the normal brain and nervous system

Intervention/exposure
Study type
Observational
Patient registry
False
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
Participants will have their fasting plasma Vitamin C and serum vitamin B12 levels measured. Blood is taken after a series of cognitive tests arte undetaken. Due to laboratory testing of vitamin C concentrations being conducted on plasma specimens, plasma was collected. This was done from the onset of the trail.
Cognitive testing will be conducted prior to the blood test. Cognition will be assessed over one and a half hours using pen and paper tests as well as a computerized testing battery ( SUCCAB) (Pipingas, 2010).
Intervention code [1] 293005 0
Not applicable
Comparator / control treatment
No Control Group
Control group
Uncontrolled

Outcomes
Primary outcome [1] 296287 0
Fasting ( 10 hours) plasma vitamin C levels. Eliza testing in which a plasma essay will be used to determine concentrations as well as a pathology company.
Timepoint [1] 296287 0
This will be tested as soon as possible following cognitve assessments
Primary outcome [2] 296289 0
Cognition assessed using the Computerised Swinburne University Computerised Cognitive Assessment Battery (SUCCAB) (Pipingas et al., 2010, Current Topics in Nutraceutical Research, Vol. 8, No. 2/3).
Timepoint [2] 296289 0
The study is a cross-sectional design. Participants will be tested at one time point and will have their blood taken and cognition assessed at one time point.
Secondary outcome [1] 318090 0
Fasting serum vitamin B12 concentrations. Eliza testing in which a serum essay will be used to determine concentrations as well as a pathology company.
Timepoint [1] 318090 0
The study is a cross-sectional design. Participants will be tested at one time point and will have their blood taken and cognition assessed at one time point.
Secondary outcome [2] 318235 0
Cognition assessed using a number of Pen and paper tests. These include the symbol digit modalities test (SDMT) and Hopkins Verbal learning test (HVLT-R).
Timepoint [2] 318235 0
The study is a cross-sectional design. Participants will be tested at one time point and will have their blood taken and cognition assessed at one time point.

Eligibility
Key inclusion criteria
- Good comprehension of written and spoken English
- Able to give informed consent
- Must not be taking antidepressants, antipsychotics, anxiolytics, illicit drugs or any cognitive enhancing drugs.
- Seeking primarily patients with low vitamin C levels (below 23 micromoles per litre).
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
- Poor comprehension of written or spoken English
- Taking antidepressants, antipsychotics, anxiolytics, illicit drugs or any cognitive enhancing drugs.
- Pregnant or lactating
- Colour blindness or any other severe visual impairment.

Study design
Purpose
Psychosocial
Duration
Cross-sectional
Selection
Defined population
Timing
Prospective
Statistical methods / analysis
A sample size calculation indicated that 80 participants was sufficient to detect a significant mean difference of 100 milliseconds (SD=211) on the spatial working memory reaction time task in the SUCCAB, with 80% power and 95% confidence. This Difference is correlated to about 10 years of age difference.(Pipingas et al., 2010, Current Topics in Nutraceutical Research, p.82, Vol. 8, No. 2/3 ).
Analyses will be performed using SPSS version 22.0 and SAS version 9.2. Statistical significance will be set at p < 0.05. Analyses will involve correlations and ANCOVAs between the cognitive scores of normal and low vitamin C status participants.
Descriptive analysis will be conducted on all study variables collected at baseline.
Regression analyses will be undertaken in order to compare vitamin C concentrations with cognitive performance. Additionally, cognitive performance will be correlated with population averages and paper and pen cognitive tests ( HVLT-R and SDMT) will be correlated with the SUCCAB.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
VIC
Recruitment postcode(s) [1] 10647 0
3122 - Hawthorn

Funding & Sponsors
Funding source category [1] 292189 0
Other Collaborative groups
Name [1] 292189 0
National Institute of Integrative Medicine (NIIM)
Address [1] 292189 0
21 Burwood Rd, Hawthorn, Vic, 3122
Country [1] 292189 0
Australia
Primary sponsor type
Other Collaborative groups
Name
National Institute of Integrative Medicine (NIIM)
Address
21 Burwood Rd, Hawthorn, Vic, 3122
Country
Australia
Secondary sponsor category [1] 290867 0
None
Name [1] 290867 0
None
Address [1] 290867 0
Country [1] 290867 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 293663 0
National Institute of Integrative Medicine Human Research Ethics Committee
Ethics committee address [1] 293663 0
21 Burwood rd, Hawthorn, Vic, 3122
Ethics committee country [1] 293663 0
Australia
Date submitted for ethics approval [1] 293663 0
21/07/2015
Approval date [1] 293663 0
03/08/2015
Ethics approval number [1] 293663 0
0025N_2015

Summary
Brief summary
Low plasma vitamin C and E have been more likely to be found in demented patients than in healthy controls. This is supported by findings from a prospective cohort study from Department of Health/Medical Research Council Nutritional Programme in which participants (n = 921; greater than or equal to 65 years) with the lowest Vitamin C status displayed the poorest cognitive function, a finding which persisted when corrected for age, illness, social class, or other dietary variables. Additionally, a recent an epidemiological prospective cohort study showed that high dietary intake of vitamin C and vitamin E may lower the risk of Alzheimer disease. Higher vitamin C blood levels have been found in association with a better memory performance among subjects older than 65 years.
Studies have shown that blood vitamin C concentration falls during acute phase responses such as after surgery, trauma, sepsis, and burns. Researchers at the University of Toronto have shown that anaesthetics following surgery can cause long-term memory loss. In a recent study, blood concentration of vitamin C decreased post-operatively and the reduction was significant 7 days after coronary heart surgery.
A study is yet to correlate paper and pen assessments such as the Mini mental State Examination (MMSE), Hopkins Verbal Learning test (HVLT-R) and symbol digit modalities test (SDMT) with a computer based cognitive testing such as the SUCCAB. The SUCCAB assesses accuracy and speed, which have been shown to correlate to cognitive decline through ageing. There is consensus that crystallised abilities (vocabulary and general knowledge) can remain stable until very late in life whereas fluid abilities (attention, executive function and memory) decline from middle adulthood until late age. The cognitive tests incorporated in the present study will primarily examine these fluid abilities. The MMSE assesses cognitive impairments in clinical and research settings. The HVLT-R is a reliable neuropsychological test of many aspects of verbal learning and memory, requiring subjects to recall as many items as possible from a list of common words. The SDMT measures the time to pair abstract symbols with specific numbers. The test requires elements of attention, visuoperceptual processing, working memory, and psychomotor speed.
Previous research measuring vitamin C has incorporated simple food questionnaires to predict vitamin C levels. The proposed study will measure serum vitamin C levels thoroughly through a means of ELISA testing. The proposed project aims to examine vitamin C serum concentration and cognitive performance measured by SUCCAB, and the pen and paper tests, including the MMSE, SDMT, and HVLT-R.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 60818 0
Mr Nikolaj Travica
Address 60818 0
National Institute of Integrative Medicine (NIIM)
21 Burwood rd, Hawthorn,VIC, 3122
Country 60818 0
Australia
Phone 60818 0
+61 421115453
Fax 60818 0
Email 60818 0
ntravica@niim.com.au
Contact person for public queries
Name 60819 0
Mr Nikolaj Travica
Address 60819 0
National Institute of Integrative Medicine (NIIM)
21 Burwood Rd, Hawthorn,VIC, 3122
Country 60819 0
Australia
Phone 60819 0
+61 421115453
Fax 60819 0
Email 60819 0
ntravica@niim.com.au
Contact person for scientific queries
Name 60820 0
Mr Nikolaj Travica
Address 60820 0
National Institute of Integrative Medicine (NIIM)
21 Burwood Rd, Hawthorn, VIC, 3122
Country 60820 0
Australia
Phone 60820 0
+61 421115453
Fax 60820 0
Email 60820 0
ntravica@niim.com.au

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary