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Кафедра молекулярной биологии и генетики 

факультета биологии и биотехнологии

КазНУ им. аль-Фараби

Southern Belt of Iron Deficiency

Anemia as a public health problem by country: Preschool-age children [Source: Worldwide Prevalence of Anemia 1993-2005, WHO 2008]

Below is excerpts of the article demonstrating the importance of investigations on anemia causes as well as the significance of distributing iron-rich food to population of so-to-speak “Southern Belt” of Anemia. All this is of special value for children and women of reproductive age.  Factors other than iron deficiency may contribute to the high prevalence of anemia: infection, inflammation, bound- as free-iron states and common under-nutrition in low-income and even middle-income countries. Deep comprehension of multiple etiology of anemia is paramount for determining most effective anti-anemia strategies and projects.
Abbreviations: ID, iron deficiency
“New Findings on Iron Deficiency Anemia: Experts Weigh In”
Tim Green & Crystal Karakochuk, Omar Dary, Reina Engle-Stone
January 11, 2017
New findings1 from a HarvestPlus-commissioned review challenge the prevailing assumption that 50% of anemia is attributable to iron deficiency (ID). The systematic review of 23 countries found that ID accounts for 25% of anemia in young children and 37% of anemia in women of reproductive age. Moreover, significant variations exist between countries, which may render generalized assumptions misleading.
How should these findings be interpreted? Should they be acted upon?  We asked nutrition experts for their viewpoints, summarized below.
Join the dialogue. We invite you to email your views on these and other related findings to j.foley@cgiar.org and we will post them here.
What major conclusions can be drawn from this paper?
Dr. Tim Green, South Australian Health and Medical Research Institute & Dr. Crystal Karakochuk, University of British Columbia: Many factors other than ID are likely contributing to the high prevalence of anemia.It’s important to assess the cause of anemia in each country-specific setting and population. Understanding the true etiology of anemia is paramount for the design and implementation of effective anemia reduction strategies and programs.
Dr. Omar Dary, United States Agency for International Development (USAID): The data is now clearer that ID could explain less than half of anemia for developing countries and some middle-income countries. The estimation that 25% and 37% of anemia is attributable to iron deficiency in children and women, respectively, coincides with a meta-analysis … which found only 27% of anemia in women could be prevented through intermittent iron supplementation2. For children younger than 12, although a 49% reduction of anemia prevalence was reported for the same treatment, variation among studies was very large3, which only shows that the 50% anemia attributable to ID was not more than a very coarse average.
Dr. Reina Engle-Stone, University of California, Davis: The specific estimates of proportion of anemia associated with ID should be interpreted with caution, because 1) the surveys were not representative globally, and the meta-analysis technique combines data from countries that may be very different, 2) there is currently no consensus on adjustment and interpretation of iron biomarkers in the presence of inflammation, which affects the estimated prevalence of ID and ID-caused anemia, and 3) cross-sectional surveys permit estimation of the proportion of anemia associated with ID, but this may not reflect the proportion of anemia that would be resolved by iron interventions.
What do these findings mean for national anemia reduction programs?
Dr. Green & Dr. Karakochuk: National surveys should measure ID and related ID-anemia prevalence, and where possible, this should include a genetic and biochemical assessment of indicators related to inflammation, infection, and iron status. The sole measurement of hemoglobin simply does not suffice.
Dr. Dary: It may no longer be valid to introduce iron supplementation as the primary intervention for anemia. The very common practice of referring to any anemia as iron deficiency anemia must be abandoned. Countries must determine the causes of anemia and if ID is important. If so, interventions to raise the intake of bioavailable iron are important regardless of the contribution of ID to anemia. ID is in itself an important deficiency to correct.
Dr. Engle-Stone: A single strategy may not be effective (or cost-effective) for all countries (or, potentially, all regions within a country). Programs may need to address multiple causes of anemia, including both nutritional deficiencies and infectious disease. It is important to understand the risk factors for anemia in a given population and ensure that this information is used in program design. Program effectiveness should also be measured to adjust the program as needed.
What’s next?
Dr. Green & Dr. Karakochuk: Assessment of genetic hemoglobin disorders is critical to understand the potential causes of anemia in a population. In Cambodia, for example, some hemoglobin disorders have also been shown to be associated with high ferritin concentrations4,5. Groundwater iron may also be a contributing factor to high iron stores with evidence from Bangladesh and Cambodia6,7.
Dr. Dary: ID must be identified with biochemical tools in a reliable, efficient, and low-cost manner. It is essential to determine the normal values for iron-status indicators for children under 2 years.
Dr. Engle-Stone: Research is needed to review cutoffs for hemoglobin and iron status indicators with respect to functional outcomes, and the role of adjustment for inflammation in nutrient status assessment; to understand the relative contributions of nutrients other than iron, as well as non-nutritional risks factors for anemia; and to compare the cost-effectiveness of different strategies to address both iron deficiency and anemia.
References: 

  1. Petry, Nicolai, et al. "The Proportion of Anemia Associated with Iron Deficiency in Low, Medium, and High Human Development Index Countries: A Systematic Analysis of National Surveys." Nutrients8.11 (2016): 693.
  2. Fernández‐Gaxiola, Ana C., and Luz Maria De‐Regil. "Intermittent iron supplementation for reducing anaemia and its associated impairments in menstruating women." The Cochrane Library(2011).
  3. De‐Regil, Luz Maria, et al. "Intermittent iron supplementation for improving nutrition and development in children under 12 years of age." The Cochrane Library(2011).
  4. George, Joby, et al. "Genetic hemoglobin disorders, infection, and deficiencies of iron and vitamin A determine anemia in young Cambodian children." The Journal of nutrition142.4 (2012): 781-787.
  5. Karakochuk, Crystal D., et al. "The Homozygous Hemoglobin EE Genotype and Chronic Inflammation Are Associated with High Serum Ferritin and Soluble Transferrin Receptor Concentrations among Women in Rural Cambodia." The Journal of nutrition145.12 (2015): 2765-2773.
  6. Merrill, Rebecca D., et al. "High prevalence of anemia with lack of iron deficiency among women in rural Bangladesh: a role for thalassemia and iron in groundwater." Asia Pacific journal of clinical nutrition21.3 (2012): 416.
  7. Karakochuk, Crystal D., et al. "Elevated levels of iron in groundwater in Prey Veng province in Cambodia: a possible factor contributing to high iron stores in women." Journal of water and health13.2 (2015): 575-586.
 
Communicated by Z.G. Aytasheva, N.A. Altybayeva, K.K. Shulembayeva, A.K. Bissenbayev
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