Department of Nutritional Sciences, University of Wisconsin-Madison
Madison, Wisconsin, 53706, United States
Completed
NCT Number: NCT03248700
Vitamin A Kinetics and Mathematical Modeling in American Women
Women were given a vitamin A tracer, and blood was sampled to determine individual and group vitamin A kinetics. Data were subsequently modeled using compartmental analysis to determine effects of study length on model outcomes.
Completed
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Notify MeKey information
Conditions
Age range
19 year–30 year
Sex eligibility
Female
Study type
Interventional
Phase
Not applicable
Primary location
About this study
This is a longitudinal study in which American women were given an oral, stable isotope tracer of vitamin A, and blood was sampled in a staggered, serial design to determine individual and group vitamin A kinetics. Data were subsequently modeled using compartmental analysis, and study truncation analysis was performed on data to investigate the factor of study duration on resulting vitamin A kinetic models and outputs related to vitamin A metabolism.
Who can participate
Healthy volunteers accepted: Yes
Only the study team can determine whether someone qualifies for participation.
Inclusion criteria
- BMI (18.5 - 24.9 kg/m2)
Exclusion criteria
- Smoker
- Pregnant
- Trying to become pregnant
- Lactating
- Weight loss > 4.5 kg during the past 3 months.
- Actively trying to lose weight
- Inability to refrain from drinking alcohol when requested
- Amenorrhea
- Acute or chronic illness including hepatitis
- Current or previous history of anorexia or bulimia
- Concurrent participation in other studies
- Family member already enrolled in the study
Treatment and study plan
Vitamin A tracer
OtherA stable isotope tracer of vitamin A was given orally.
Other names: 13C vitamin A, 13C retinyl acetate
Primary outcomes
-
Total traced vitamin A mass
Time frame: Baseline through 152 days
Total amount of endogenous vitamin A determined by mathematical model, (µmol).
Secondary outcomes
-
Compartmental model complexity
Time frame: Baseline through 152 days
Required number of compartments in mathematical model needed to adequately fit data.
-
Compartmental model fractional transfer coefficients
Time frame: Baseline through 152 days
Model parameters adjusted to fit analytical data. Represents the fractional transfer from one compartment to another in the model, (pools/d, represented as L(i,j), the fraction of compartment J transferred to compartment I per day).
-
Serum vitamin A half-life
Time frame: Baseline through 152 days
Half-life of vitamin A in serum, (d).
-
Vitamin A disposal rate
Time frame: Baseline through 152 days
Daily loss or utilization of vitamin A, (µmol/d).
-
Vitamin A equilibration time and partitioning
Time frame: Baseline through 152 days
Time taken for vitamin A to equilibrate with body stores, (d).
-
Vitamin A tracer partitioning
Time frame: Baseline through 152 days
Body partitioning of tracer between serum and extravascular compartment(s), relative to total tracee mass. Calculated as a ratio of tracer-to-tracee ratio (TTR) in serum and extravascular stores, (TTR serum / TTR stores).
-
Vitamin A dietary intake
Time frame: Baseline
Vitamin A dietary intake by food frequency questionnaire, (µg retinol activity equivalents/d).
Sponsors and collaborators
Lead sponsor
University of Wisconsin, Madison
Other
Registry information
Important dates
- Study start
- 2008
- Primary completion
- 2008
- Study completion
- 2016
- First posted
- Aug 14, 2017
- Registry last updated
- Oct 31, 2019
OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.
View the official ClinicalTrials.gov record (opens in a new tab)This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.