A randomized controlled trial to determine the effect of reducing iodine from vitamin and mineral supplements for pregnant women who have adequate iodine intakes (\>165 μg/d from food alone) on cognitive development of children at 24 months of age.
It is known that severe iodine deficiency during pregnancy leads to profound intellectual disabilities in the child. Following results of a 2004 national survey of school-aged children showing that mild iodine deficiency had re-emerged in the south-eastern parts of Australia, the Australian government mandated the addition of iodine to salt used in bread making to increase population iodine intake. It is also recommended that all pregnant and lactating women take an additional iodine supplement containing 150 µg/d of iodine. Since this time, further evidence has emerged from cohort studies that children born to women with high iodine intake (as well as low iodine intake) have poorer neurodevelopmental scores, suggesting that more tailored supplementation may be a better strategy. Our PoppiE trial will determine if limiting iodine supplementation in women who already consume adequate iodine from food, improves cognitive scores in early childhood. A total of 754 pregnant women from around Australia who are ≤13 weeks of gestation will be enrolled and randomised to receive a standard prenatal vitamin and mineral supplement with a reduced amount of iodine (20 μg - intervention) or a standard prenatal vitamin and mineral supplement with 200 μg of iodine (control). The control supplement contains a level of iodine to match the amount in most commonly used vitamin and mineral supplements sold in Australia. Infant neurodevelopment at 24 months of age will be assessed using the Bayley-IV and conducted at participating centres or a location convenient to the family.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
PREVENTION
Masking
QUADRUPLE
Enrollment
794
Multivitamin and mineral supplement with reduced iodine
Multivitamin and mineral supplement with standard amount of iodine to match current leading brands of prenatal supplements
South Australian Health and Medical Research Institute
North Adelaide, South Australia, Australia
Infant Developmental quotient (DQ)
The Bayley Scales of Infant and Toddler Development, 4th Edition Cognitive Scale score has a mean of 100 and standard deviation of 15, where higher scores indicate a better outcome. As the Bayley scales are age-standardized scales the exact minimum and maximum score depends on the exact age of the child at the time of the assessment, hence we have instead provided the mean and standard deviation (as is the norm when reporting standardized psychometric assessments).
Time frame: 24 months of age
Language development of infants using Bayley-IV
The Bayley Scales of Infant and Toddler Development, 4th Edition Language Scale score has a mean of 100 and standard deviation of 15, where higher scores indicate a better outcome.
Time frame: 24 months of age
Motor development of infants
The Bayley Scales of Infant and Toddler Development, 4th Edition Motor Scale score has a mean of 100 and standard deviation of 15, where higher scores indicate a better outcome.
Time frame: 24 months of age
Behavioral and emotional development
Behavioral and emotional development of infants using the Infant Toddler Social Emotional Assessment (ITSEA). The Infant-Toddler Social \& Emotional Assessment scale has range of 0-100 where higher T scores indicate a worse outcome.
Time frame: 24 months of age
Health service utilization
Health service utilisation of children assessed through data linkage of the Medicare Benefits Schedule, Pharmaceutical Benefits Scheme to evaluate the cost effectiveness of the intervention.
Time frame: 24 months of age
Length of gestation
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.
The gestational age in days at birth (or other event of interest) will be determined from the estimated date of delivery using the equation \[280 - (estimated date of delivery - date of birth)\].
Time frame: Birth
Infant Birth Anthropometrics
Infant weight, length and head circumference will be analysed, using both the raw measurements and Z-scores for corresponding gestational age and sex, using means and standard deviations.
Time frame: Birth
Admission to special care baby unit (level 2 nursery).
Any admission to a special care baby unit or level 2 nursery up to 28 days post birth.
Time frame: The neonatal period including birth to 28 days of age
Thyroid stimulating hormone (TSH) level
Ascertained from Neonatal Screening Test
Time frame: Within 5 days of birth
Infant Anthropometrics
Average weight, height and head circumference measurements at 24 months of age will be converted to z-scores using WHO growth standards. For preterm infants, corrected age at the time of the measurement rather than chronological age will be used in deriving the z-scores.
Time frame: 24 months of age