Aflatoxin Birth Cohort Study Nepal (AflaCohort)
Condition: Stunting; Birth Weight; Birth Length; Height for Age; Linear Growth Failure
MeSH terms: Birth Weight; Growth Disorders; Failure to Thrive
Study type: Observational

Summary: 
      The study focuses on the causal relationship between mycotoxin exposure (particularly
      aflatoxin B1), birth outcomes, and height for age among young children in Nepal. Previous
      studies have shown a strong association of stunting with mycotoxin exposure yet causality has
      not been proven. Thus, this study will provide a better understanding of the association
      between maternal and/or early life mycotoxin exposure (rates in the blood and breast milk)
      and infant and young child growth. This information is essential if we are to more fully
      understand and effectively address the high rates of stunting in Asia.
    

Detailed description: 
      In 2012, a research prioritization meeting organized by IFPRI and the Bill and Melinda Gates
      Foundation on food-borne toxins concluded, "While there is solid association of stunting with
      exposure to mycotoxins, the causality has not been proven and the percentage of stunting
      attributable to mycotoxins in general or to specific mycotoxins is not known." (IFPRI/BMGF
      2012) In other words, the extent of the problem, although widely suspected, has been poorly
      documented and the biological mechanisms thought to be involved remain poorly understood.

      To contribute to a better understanding of the mycotoxin-stunting relationship, the Feed the
      Future Feed the Future Nutrition Innovation Lab-Asia proposes to explore the impact of
      mycotoxins, with a focus on mycotoxins on child nutrition in Nepal. Through its PoSHAN study,
      the Nutrition Innovation Lab-Asia is currently undertaking research in Nepal in collaboration
      with the Child Health Division of the Ministry of Health and Population and multiple local
      partners on how investments in agriculture can achieve significant impacts on maternal and
      child nutrition, and on demonstrating how large-scale programs best incorporate such evidence
      into cost-effective multi-sectoral interventions. Adding a study component on food safety
      (mycotoxin contamination of the food supply) will significantly enhance our understanding of
      nutrition outcomes linked to investments in agriculture. As noted by participants of the
      IFPRI/BMGF (2012) meeting, "only 35% of stunting of children can be attributed to known
      factors". This leaves room for research to uncover other suspected contributors to the
      world's huge nutrition problems, which could then lead testable recommendations for
      innovative interventions to address newly identified factors. The team will assess current
      mycotoxin risk so that potential mitigation strategies can be developed.

      Given the significant statistical associations shown between mycotoxin exposure in children
      and height gain in infants and young children, the Nutrition Innovation Lab-Asia will
      undertake an mycotoxin birth cohort study to further the understanding of the causal
      relationship between past and current mycotoxin exposure (maternal and infant), birth
      outcomes and length-for-age in Nepali infants and young children. The study will also seek to
      validate the use of low cost data collection methods (e.g. dried blood spots versus venous
      blood samples) for mycotoxin analysis.

      The specific aims of this study are:

        1. To examine the relationship of maternal mycotoxin exposure in pregnancy and birth
           outcomes, including infant birth weight.

        2. To examine the relationship of exposure to mycotoxin of infants through breast milk and
           their linear growth.

        3. To examine the relationship of exposure to mycotoxin through complementary feeding and
           linear growth.

        4. To enumerate the relative contributions of maternal and infant mycotoxin exposures in
           impairing linear growth, controlling for other potential explanatory factors.

      Controlling for factors such as diet, maternal education, maternal height and BMI, household
      socio-economic status, infections and inflammation, and other elements such as storage
      patterns, knowledge of food contaminants and mitigation practices, the specific hypotheses of
      this study are:

        1. There is an incremental effect of in utero, lactation and complementary feeding
           mycotoxin exposures on rate of length gain and stunting outcomes for age Z-scores in
           children at 2 year of age.

        2. Maternal exposure to mycotoxins will be significant predictor of birth weight in
           infants, thereby being a significant contributor to the burden of stunting at 2 years of
           age.

        3. Exposure to mycotoxins through breast milk before 6 months of age along with continued
           exposure through both breast milk and complementary foods (after 6 months of age) is a
           significant contributor to the burden of stunting at 2 years of age.

        4. Improper farm management, food processing and storage practices are significantly
           related to higher levels of serum mycotoxins in the blood of mothers and their children.

        5. Knowledge of the problem of food-borne contaminants is associated with improved food
           processing and storage practices.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        All pregnant women and adolescent girls aged 16-49 years and living in the study areas will
        be invited to join the study. Women who are less than 30 weeks into their gestation will be
        eligible to participate if their expected delivery date falls within the enrollment period.
      
Biospecimen description: 
      Serum aflatoxin B1-lysine adduct levels Breast milk aflatoxin M1 levels
    
Keywords: Aflatoxin B1; Aflatoxin M1; Aflatoxin; Mycotoxin; Stunting; Linear growth; Pregnancy; Birth outcomes; Nepal