Effect of low-dose versus higher-dose antenatal iron supplementation on child health outcomes at 36 months of age in Viet Nam: longitudinal follow-up of a cluster randomised controlled trial

Sarah Hanieh; Tran T Ha; Julie A Simpson; Sabine Braat; Tran T Thuy; Thach D Tran; Janet King; Tran Tuan; Jane Fisher; Beverley-Ann Biggs

doi:10.1136/bmjgh-2017-000368

Effect of low-dose versus higher-dose antenatal iron supplementation on child health outcomes at 36 months of age in Viet Nam: longitudinal follow-up of a cluster randomised controlled trial

BMJ Glob Health. 2017 Sep 22;2(3):e000368. doi: 10.1136/bmjgh-2017-000368. eCollection 2017.

Authors

Sarah Hanieh¹, Tran T Ha², Julie A Simpson³, Sabine Braat³, Tran T Thuy², Thach D Tran^{2

4}, Janet King⁵, Tran Tuan², Jane Fisher⁴, Beverley-Ann Biggs^{1

6}

Affiliations

¹ Department of Medicine, University of Melbourne, Peter Doherty Institute for Immunity and Infection, Parkville, Victoria, Australia.
² Research and Training Centre for Community Development, Hanoi, Viet Nam.
³ Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne, Victoria, Australia.
⁴ The Jean Hailes Research Unit, School of Public Health and Preventive Medicine, Monash University, Melbourne, Victoria, Australia.
⁵ Children's Hospital Oakland Research Institute, Oakland, California, USA.
⁶ The Victorian Infectious Diseases Service, Royal Melbourne Hospital, Parkville, Victoria, Australia.

Abstract

Introduction: Intermittent iron-folic acid supplementation (IFA) is currently recommended for pregnant women in populations where anaemia prevalence among pregnant women is <20% or if daily iron is not acceptable. The effect of providing lower doses of antenatal elemental iron through intermittent regimes on longer-term health outcomes in childhood is unclear.

Methods: A prospective cohort study conducted between May 2012 and May 2014 in Viet Nam among children of 36 months of age, born to women previously enrolled in a cluster randomised controlled trial of antenatal micronutrient supplementation (daily IFA (60 mg elemental iron) vs twice-weekly IFA (60 mg elemental iron) vs twice-weekly multiple micronutrient (MMN) supplementation (60 mg elemental iron)). Primary outcomes were height-for-age z-scores (HAZ), according to WHO growth standards and cognitive composite scores (Bayley Scales of Infant and Toddler Development, third edition) at 36 months of age.

Results: A total of 1017 children born to mothers enrolled in the cluster randomised trial were assessed at 36 months of age. Adjusted mean differences (MDs) in HAZ were -0.14 (95% CI -0.28 to -0.01) and -0.15 (95% CI -0.29 to -0.01) in children born to mothers who received twice-weekly IFA or MMN compared with those who received daily IFA. Children born to mothers who received twice-weekly MMN had lower composite motor scores compared with those who received daily IFA (MD -2.07, 95% CI -4.11 to -0.03). There were no differences in composite cognitive scores in the twice-weekly compared with daily regimens.

Conclusions: Low-dose antenatal IFA supplementation (120 mg elemental iron per week) resulted in lower HAZ and motor composite scores in children compared with higher-dose antenatal IFA supplementation (420 mg elemental iron per week). This highlights the importance of adequate iron stores during pregnancy and the need for careful monitoring when lower-dose antenatal iron regimens are used.

Trial registration number: Australia New Zealand Clinical Trials Registry: 12610000944033.

Keywords: Maternal health; child health; nutrition; public health.