Using Stable Isotope Techniques to Monitor and Assess the Vitamin A Status of Children Susceptible to Infection

Summary

The combination of infectious diseases and malnutrition is the most prevalent, preventable public health problem in the world, responsible for millions of deaths annually, particularly in infants and children. Approximately 13 million children die each year in developing countries from infectious diseases, with the majority of these deaths related to malnutrition. The relationship between infections and malnutrition is synergistic, each further compromising the outcome of the other. Malnutrition compromises natural immunity leading to increased susceptibility to infections, more frequent and prolonged disease episodes, and increased severity of disease. Likewise, infections can aggravate or precipitate malnutrition through decreased appetite and food intake, nutrient malabsorption, nutrient loss or increased metabolic needs. Another issue is that infections (as well as overweight and obesity status) affect nutritional biomarkers making it difficult to assess the real magnitude of some nutritional problems. This is the case of vitamin A. Vitamin A deficiency is defined to be of severe public health importance if 20% or more of a defined population has a serum retinol concentration of less than 0.7 µmol/L. However, circulating concentrations of serum retinol are reduced by infections and in such situations serum retinol concentration is not a good indicator of vitamin A status. Serum acute-phase proteins can indicate the severity and duration of an infection. Correcting vitamin A deficiency is addressed in Ethiopia through vitamin A supplementation of children, dietary diversity and using bio-fortified foods. However, assessing vitamin A status, and the effectiveness of government interventions, is challenging in settings where infectious diseases are endemic, as in most area of the country. Evaluation of vitamin A status is relatively insensitive when based on changes in serum retinol concentrations, which are homeostatically controlled and negatively affected by subclinical infections. Liver stores of vitamin A, the best indicator of vitamin A status, cannot be routinely evaluated. The isotope dilution technique is the preferred method for determining vitamin A status and assessing the efficacy and effectiveness of intervention programs aimed at improving vitamin A status. It is the only indirect assessment method that provides a quantitative estimate of vitamin A status across the continuum of deficient to excessive stores.

Conditions

• Vitamin A Deficiency

Interventions

DIETARY_SUPPLEMENT

Mega-dose of vitamin A supplement

vitamin A supplementation normally given every six months for under five children in Ethiopia. In addition, there is also dietary intervention like orange flash sweet potato and promotion of other vitamin A rich foods to tackle vitamin A deficiency in Ethiopia.

Sponsors & Collaborators

• International Atomic Energy Agency

  collaborator OTHER_GOV

• Ethiopian Public Health Institute

  lead OTHER_GOV

Principal Investigators

• Cornelia Loechl, PhD · International Atomic Energy Agency

Study Design

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

3 Years

Max Age

5 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2017-03-01

Primary Completion

2017-06-30

Completion

2017-06-30

Countries

• Ethiopia

Study Locations