Prenatal iodine supplementation and early childhood neurodevelopment: the PoppiE trial - study protocol for a multicentre randomised controlled trial.

Introduction: Observational studies suggest both low and high iodine intakes in pregnancy are associated with poorer neurodevelopmental outcomes in children. This raises concern that current universal iodine supplement recommendations for pregnant women in populations considered to be iodine sufficient may negatively impact child neurodevelopment. We aim to determine the effect of reducing iodine intake from supplements for women who have adequate iodine intake from food on the cognitive development of children at 24 months of age.

Change in Australian Vitamin A Intakes over Time.

Background: The mean intake of vitamin A of Australians aged 2 y and older was 300 µg retinol equivalents lower in the 2011-2012 national nutrition survey than in 1995 and decreases preponderated in adults rather than young children.

Objective: This aim of this study was to identify the foods associated with this change and to examine how the method used to adjust for within-person variability affects the estimated prevalence of inadequate intakes in both surveys.

Methods: Foods contributing to vitamin A intake were calculated from the first day of data.

Iodine status of Indigenous and non-Indigenous young adults in the Top End, before and after mandatory fortification.

Objective: To assess the median urine iodine concentration (UIC) of young adults in the Top End of Northern Territory, before and after fortification of bread with iodised salt became mandatory.

Design, Setting: Analysis of cross-sectional data from two longitudinal studies, the Aboriginal Birth Cohort and the non-Indigenous Top End Cohort, pre- (Indigenous participants: 2006-2007; non-Indigenous participants: 2007-2009) and post-fortification (2013-15).

Participants: Indigenous and non-Indigenous Australian young adults (mean age: pre-fortification, 17.

Plasma retinol and total carotenes and fracture risk after long-term supplementation with high doses of retinol.

Objective: Observational studies suggest that moderate intakes of retinol and increased circulating retinol levels may increase fracture risk. Easy access to supplements, combined with an aging population, makes this a potentially important association. The aim of this study was to investigate plasma retinol and total carotene concentrations in relation to fracture risk after long-term supplementation with retinol and/or beta-carotene in 998 adults between 1990 and 2007.

Intraindividual variation in urinary iodine concentrations: effect of adjustment on population distribution using two and three repeated spot urine collections.

Objectives: To determine the effect of adjustment for intraindividual variation on estimations of urinary iodine concentrations (UIC), prevalence of iodine deficiency and population distribution of iodine status.

Setting: Community-dwelling older adults from New South Wales, Australia.

Participants: 84 healthy men and women aged 60-95 years were recruited prior to introduction of the mandatory iodine fortification programme.

No dose-dependent increase in fracture risk after long-term exposure to high doses of retinol or beta-carotene.

Unlabelled: Uncertainty remains over whether or not high intakes of retinol or vitamin A consumed through food or supplements may increase fracture risk. This intervention study found no increase in fracture risk among 2,322 adults who took a controlled, high-dose retinol supplement (25,000 IU retinyl palmitate/day) for as long as 16 years. There was some evidence that beta-carotene supplementation decreased fracture risk in men.

Estimating the iodine supplementation level to recommend for pregnant and breastfeeding women in Australia.

Objective: To identify a level of iodine supplementation to recommend for pregnant and breastfeeding women in Australia.

Design, Setting And Participants: Dietary modelling indicated that mandatory fortification of bread with iodine by replacing salt with iodised salt would still leave a gap in iodine intakes in pregnant and breastfeeding women in Australia. Iodine shortfall was estimated by two separate methods: (i) analysis of data from published studies reporting mean urinary iodine concentrations in populations of Australian women who were pregnant or had given birth in the past 6 months; and (ii) modelling based on the postmandatory fortification iodine intake estimates calculated by Food Standards Australia New Zealand using food consumption reported by women aged 19-44 years who participated in the 1995 National Nutrition Survey.

Risk assessment to underpin food regulatory decisions: an example of public health nutritional epidemiology.

The approach used by food regulation agencies to examine the literature and forecast the impact of possible food regulations has many similar features to the approach used in nutritional epidemiological research. We outline the Risk Analysis Framework described by FAO/WHO, in which there is formal progression from identification of the nutrient or food chemical of interest, through to describing its effect on health and then assessing whether there is a risk to the population based on dietary exposure estimates. We then discuss some important considerations for the dietary modeling component of the Framework, including several methodological issues that also exist in research nutritional epidemiology.

Iodine status of Aboriginal teenagers in the Darwin region before mandatory iodine fortification of bread.

Objective: To determine the iodine status of participants in the Aboriginal Birth Cohort Study who resided in the Darwin Health Region (DHR) in the "Top End" of the Northern Territory prior to the introduction of mandatory iodine fortification of bread.

Design, Setting And Participants: Participants in our study had been recruited at birth and were followed up at a mean age of 17.8 years.

Estimating the impact of mandatory fortification of bread with iodine on pregnant and post-partum women.

Background: Iodine deficiency has re-emerged in Australia. Pregnant and breastfeeding women need higher iodine intakes (estimated average requirements: 160 μg/day and 190 μg/day) than non-pregnant women (100 μg/day) because iodine is critical for early infant development. The impact of iodine fortification of bread on women's iodine intake is evaluated by reproductive status using 2003 Australian Longitudinal Study on Women's Health (ALSWH) food frequency data and projected onto 1995 National Nutrition Survey (NNS) daily food consumption data for women of child-bearing age.

Australian Aboriginal Birth Cohort study: follow-up processes at 20 years.

Background: In 1987, a prospective study of an Australian Aboriginal Birth Cohort was established focusing on the relationships of fetal and childhood growth with the risk of chronic adult disease. However as the study is being conducted in a highly marginalized population it is also an important resource for cross-sectional descriptive and analytical studies. The aim of this paper is to describe the processes of the third follow up which was conducted 20 years after recruitment at birth.

Dietary patterns identified using factor analysis and prostate cancer risk: a case control study in Western Australia.

Purpose: Dietary patterns offer an alternative method for analyzing dietary intakes that take into account the whole diet. We investigated empirical dietary patterns and prostate cancer risk in Western Australia (WA) using a population-based case-control study.

Methods: Incident prostate cancer cases were identified via the WA Cancer Registry.

Dietary patterns and surgically treated benign prostatic hyperplasia: a case control study in Western Australia.

Objectives: To investigate dietary patterns and food intake as risk factors for surgically treated benign prostatic hyperplasia (BPH), as few risk factors have been established for BPH and recently there has been some interest in a role for diet in the development of BPH.

Patients, Subjects And Methods: A case-control study was conducted in Western Australia (WA) during 2001 and 2002. BPH cases were men with a diagnosis of BPH hospitalized for their first prostatectomy.

Growth outcomes for Australian Aboriginal children aged 11 years who were born with intrauterine growth retardation at term gestation.

Long-term poor growth outcomes are well documented for intrauterine growth-retarded babies (IUGR) in developed populations but there is a paucity of IUGR studies from disadvantaged populations where the greatest burden of IUGR occurs. Using a Northern Territory, Aboriginal cohort recruited at birth and followed up at a mean age of 11.4 years, comparisons of body size were made between children born at term who had been IUGR (n = 121) and those non-IUGR (n = 341), and between those IUGR babies who had an appropriate ponderal index at birth (n = 72) and those with a low ponderal index (n = 49).

Fruit, vegetable, vitamin A intakes, and prostate cancer risk.

Prostate cancer risk was examined in relation to intakes of fruit, vegetables, beta-carotene and retinol. Subjects were a cohort of 1985 men previously to asbestos who participated in a cancer prevention programme of beta-carotene and retinol supplements that commenced in July 1990. Diet was assessed at entry to the programme.

Does the store-turnover method still provide a useful guide to food intakes in Aboriginal communities?

Objective: To consider the application of the store-turnover method as a guide to assess food intake in remote Aboriginal communities.

Method: Food sources in a remote Aboriginal island community were documented. The contribution of quantifiable food sources to total community-level fresh fruit and vegetable availability was determined.

The prevalence of anaemia depends on the definition: an example from the Aboriginal Birth Cohort Study.

Objective: The cutoffs defining anaemia based on haemoglobin and haematocrit recommended by the World Health Organization (WHO) and the United States (US) are different. We compared the prevalences resulting from these definitions and explored the reasons for the variation observed.

Design: A cross-sectional survey within a cohort study of children recruited at birth at Royal Darwin Hospital.

Leanness and type 2 diabetes in a population of indigenous Australians.

Objective: To determine the prevalence of type 2 diabetes and its risk factors in a population of indigenous Australians.

Research Design And Methods: A cross-sectional study of 332 indigenous community residents aged 15 years and over with fasting blood samples and anthropometric measurements.

Results: Almost half of the study population (47.

24-hour national dietary survey data: how do we interpret them most effectively?

Objective: To illustrate the effect of common mistakes when using 24-hour national dietary survey data to estimate the prevalence of inadequate nutrient intakes.

Design: Raw data on nutrient intake from the Australian 1995 National Nutrition Survey were adjusted for within-person variance using standard techniques and corrected for underreporting using the criteria of Goldberg et al. The distributions for six nutrients were compared with current dietary reference values from the UK, USA and Australia.

Haematocrit levels and anaemia in Australian children aged 1-4 years.

The aim of this study was to describe the prevalence of anaemia, mean haematocrit levels, and the risk factors influencing haematocrit in participants of the 1995 National Survey of Lead in Children. A nationally-representative cross-sectional survey of children aged 1-4 years inclusive was done. Mean haematocrit and the proportion with anaemia using both the US and WHO haematocrit-based criteria were calculated.

In an Aboriginal birth cohort, only child size and not birth size, predicts insulin and glucose concentrations in childhood.

The objectives were to describe cross-sectional growth in 279 Australian Aboriginal children aged 8-14 years in order to test the hypothesis that birth size interacts with child size to predict glucose and insulin metabolism. Cross-sectional growth outcomes were described using standard deviation scores or z-scores for height for age (HAZ) and weight for age (WAZ) calculated from CDC 2000 reference values in Epi Info 2000. Interrelationships were examined using standard regression models with current height and weight and birth weight, ponderal index and birth weight below the 10th percentile for gestational age.