Closing the knowledge gap: Finding the most effective protocol for large-scale preventive zinc intervention programs

Where: urban slums of Dhaka, Bangladesh

Age group: 9-11 months 

Number to enroll: 2886 children

Trial started: February 2018

Trial expected completed: January 2020

Partners: IZiNCG, icddr,b, CHORI, JHU, CU

Registration: https://clinicaltrials.gov/ct2/show/NCT03406793

Preventive, daily supplementation with 7-10 mg of zinc in the form of dispersible tablets can significantly decrease the incidence of diarrhea and pneumonia, and may improve growth and decrease hospitalizations (12). 

Yet, few countries have established comprehensive zinc supplementation programs for the prevention of zinc deficiency, and no global recommendations exist.  

Multiple Micronutrient Powder (MNP) programs are being scaled up globally and present a golden opportunity for delivering preventive zinc to older infants and young children. 

Most MNPs contain either 5 mg (in 5-component MNP) or 4.1 mg (in 15-component MNP) of zinc. Our knowledge gap is that the expected outcomes such as decreased diarrhea and pneumonia, and improved growth observed with zinc tablets, have generally not been observed with MNP use (3).  There may be several reasons for this:

·     Is the amount of zinc in the MNP too low?

·     Does consuming zinc together with other minerals and vitamins diminish the impact of zinc?

·     Does the effect of zinc depend on whether it is consumed with food vs. as a standalone supplement?

There has also been some concern about an increasein thenumber of days with diarrhea observed in some studies (45), possibly related to the amount or form of iron in the MNP. 

To enable the benefits of zinc to be actualized, there is a need to examine the zinc component of MNP and test different amounts of zinc or other nutrients of concern (e.g., iron) compared to a standard MNP composition, a positive control (daily zinc in the form of dispersible tablets) and a placebo control on functional outcomes such as diarrhea and growth. 

Bangladesh was chosen for the study because of the high prevalence of zinc deficiency (44.6%), the high rates of diarrhea and stunting, and the expertise of icddr,b. The trial is underway in urban slums of Dhaka, aiming to enroll 2886 children aged 9-11 months. 

All children will continue to receive therapeutic zinc supplementation along with ORS for treatment of diarrhea, for which coverage is quite high in Bangladesh.  As such, the proposed study will actually examine the incremental benefit of preventive zinc supplementation on the study outcomes over and above what is currently afforded by therapeutic zinc supplementation. 

The results from this direct comparison of five different regimens of preventive zinc supplements plus a placebo control will identify the most effective protocols to consider for large-scale preventive zinc intervention programs.

For related publications, click here.

References

1.         Brown KH, Peerson JM, Baker SK, Hess SY. Preventive zinc supplementation among infants, preschoolers, and older prepubertal children. Food Nutr Bull. 2009;30(1 Suppl):S12-40.

2.         Brown KH, Hess SY, Vosti SA, Baker SK. Comparison of the estimated cost-effectiveness of preventive and therapeutic zinc supplementation strategies for reducing child morbidity and mortality in sub-Saharan Africa. Food Nutr Bull. 2013;34(2):199-214.

3.         De-Regil LM, Suchdev PS, Vist GE, Walleser S, Peña-Rosas JP. Home fortification of foods with multiple micronutrient powders for health and nutrition in children under two years of age (Review). Evid Based Child Health. 2013;8(1):112-201.

4.         Soofi S, Cousens S, Iqbal SP, Akhund T, Khan J, Ahmed I, et al. Effect of provision of daily zinc and iron with several micronutrients on growth and morbidity among young children in Pakistan: a cluster-randomised trial. Lancet. 2013;382(9886):29-40.

5.         Salam RA, MacPhail C, Das JK, Bhutta ZA. Effectiveness of Micronutrient Powders (MNP) in women and children. BMC Public Health. 2013;13 Suppl 3:S22.