Menzies’ NHMRC early career fellow, Dr Michael Binks was recently awarded a competitive grant as part of the National Health and Medical Research Council’s (NHMRC) yearly multi-million dollar funding round. His $3 million project grant is titled: Vitamin D supplementation to prevent respiratory infections among Indigenous children in the Northern Territory: a randomised controlled trial.

Michael shared his thoughts on the new funding.

What major health issue does your research hope to address and how?

Nationally, mortality due to respiratory infection is more than four times higher among Indigenous compared to non-Indigenous children. For Indigenous children in the Northern Territory (NT), acute respiratory infections are the most common cause of hospitalisation and a leading cause of preventable death.

Several years ago we showed that Indigenous infants with lower vitamin D at birth were more likely to be hospitalised with an acute respiratory infection during their first year of life. A recent evaluation of randomised controlled trials suggests vitamin D supplementation could reduce the risk of acute respiratory infections by over 20%. To date, few vitamin D trials have involved infants, and no trials have included Australian Indigenous infants.

With this funding we will conduct a randomised controlled trial among Indigenous mother-infant pairs in the NT to determine whether vitamin D supplementation (compared to placebo) during pregnancy and early infancy reduces the incidence of acute respiratory infections during the infants’ first 12 months of life.

What is the most exciting aspect of your funding win?

I first began investigating the vitamin D status of Indigenous children several years ago during my PhD here at Menzies. At the time there was relatively little interest in vitamin D in the NT due to the abundance of sunshine in this region. When we showed that suboptimal vitamin D levels were common among Indigenous infants at birth and that lower levels were associated with an increased risk of subsequent respiratory infection, we were intrigued. Vitamin D ties to respiratory infection via its ability to regulate pathogen immune responses. I was already planning a clinical trial in the back of my mind.

There is a need for practical interventions that can prevent respiratory infections among Indigenous infants and vitamin D supplementation is a promising strategy. Vitamin D supplementation is a simple, safe, accessible and cost effective intervention. It is really exciting to now be able to consolidate our many years of research into a randomised controlled trial.

What are the proposed details of your research methodology?

The study will be conducted in urban and remote communities of the NT where we have established relationships. Pregnant Indigenous mothers will be identified and recruited during visits for ante-natal care at community-based maternity clinics and government hospitals and their babies will be followed from birth to 12 months. 

We aim to recruit 440 mother-infant pairs, randomised 1:1 to receive either daily vitamin D or placebo. A phone-based application will be developed and used to remind participants to take the study medication and to monitor adherence.

Vitamin D levels, acute respiratory infections and pathogens will be monitored longitudinally throughout. Infant immune responses will be characterised at age four months. Key genotypes of the vitamin D binding protein and the vitamin D receptor will be determined for each child to characterise their ability to utilise vitamin D.

What are the broader health implications of your grant?

Currently, in Australia there is no routine vitamin D food fortification, screening or supplementation of pregnant women or infants. For the NT and more broadly, this trial will validate the utility of vitamin D supplementation against infant acute respiratory infection, guide best practice for vitamin D supplementation and provide much needed local evidence on vitamin D reference ranges in pregnancy and infancy.

Importantly, we will determine whether participant level differences in vitamin D utilisation influence the effectiveness of supplementation against clinical and immunological outcomes.

The study outcomes will make an important contribution to clinical practice, the medical literature and have implications for all disadvantaged populations where acute respiratory infections are common. Additionally, we will provide employment, training and education materials to Indigenous and non-Indigenous health workers, nurses and researchers which are an essential part of the ongoing effort to improve Indigenous health outcomes. Results from our study will be generalisable to other Indigenous settings and internationally. As our team involves clinicians who also write the guidelines for Indigenous health, our study’s results will be translated rapidly in Australia.

What are the timeframes for your project and any other major milestone dates?

This is a five-year project.

  • Logistics (community engagement, approvals/registrations, staff, study medication) will commence in early 2018.
  • Recruitment will begin during 2019 with follow-up to be complete by mid-2022.
  • Laboratory work, data analysis, feedback and publication will be complete by the end of 2022.