1 / 34

Pediatric Micronutrient Deficiencies, Epidemiology and prevention II. Vitamin A and iodine Drora Fraser

Pediatric Micronutrient Deficiencies, Epidemiology and prevention II. Vitamin A and iodine Drora Fraser. Drora Fraser. Director of the S. Daniel Abraham International Center for Health and Nutrition, Ben-Gurion University of the Negev (BGU), Beer-Sheva, Israel.

rachana
Download Presentation

Pediatric Micronutrient Deficiencies, Epidemiology and prevention II. Vitamin A and iodine Drora Fraser

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Pediatric Micronutrient Deficiencies, Epidemiology and prevention II. Vitamin A and iodineDrora Fraser

  2. Drora Fraser Director of the S. Daniel Abraham International Center for Health and Nutrition, Ben-Gurion University of the Negev (BGU), Beer-Sheva, Israel. Member of the Epidemiology and Health Services Evaluation Department, Faculty of Health Sciences, BGU.

  3. Course Objectives: • To familiarize the students with the extent of the problems of micronutrient deficiencies worldwide • To understand the implications of those problems • Using the models of micronutrient interventions studied, learn the possible methods available and judge their applicability to their own specific situation

  4. Prevalence of Vitamin A Around the world • 250 million children vitamin A deficient (serum retinol <0.70 mol/l) • 3 million children have xerophthalmia (“dry eyes”) • Areas with high rates of night blindness in children also have high rates of night blindness in mothers

  5. Vitamin A deficiency: consequences • Night blindness - ancient Egypt, Greek and Assyrian medical literature • Early deaths • High rates of respiratory and diarrheal diseases • Affects immunocompetence • Cured with animal and fish liver or plants with green and yellow pigments

  6. Risk factors for VAD • Age • Diet • Disease • Seasonality • Culture • Clustering

  7. VAD status Death Hepatotoxicity Bone fracture Hemorrhage Eczema Vit A level Night blindness Xerophthalmic keratinization Death Vit A intake µg/kg body weight

  8. Public Health indicatorsof VAD and it’s importance

  9. Ecological indicatorsof VAD

  10. Illness related indicators for 6-71 month old children

  11. Preferred approach to prevention of VAD -1

  12. Preferred approach to prevention of VAD-2

  13. Nutrition intervention programs Critical elements for successful programs are: • Political commitments • Community mobilization & participation • Human resources development • Targeting • Monitoring, evaluation & management information systems • Replicability and sustainability

  14. Dietary modification for VAD Ex. Where food sources of vitamin A are underutilized: • Thailand: VAD in preschool children, pre-clinical levels, • Animal foods expensive • Fruits are seasonal • Ivy gourd-underutilized, low esteem

  15. Dietary modification for VAD Ex. Home and community provision of vitamin A rich foods • Bangladesh: gardening projects-women • High night blindness despite bi-annual supplementation programs • Low cost gardening techniques • Innovative resources, locally adapted

  16. Fortification of VAD EX. Guatemala; sugar fortification • Low serum retinol levels • Low dietary intake of vitamin A • Sugar usually refined • Sugar consumed within a narrow range of daily intake across age groups • In 1970, sugar was fortified with vitamin A, program very successful (Arroyave, 1979 PAHO publication)

  17. Vitamin A supplementation High dose vitamin A supplementation has been used in various countries • Need high coverage >65% of population • Repeat delivery every 4-6 M required • Repeat delivery difficult to maintain • Easiest to integrate with other health care delivery

  18. Vitamin A supplementation High dose vitamin A supplementation EX: Brazil • North Eastern Brazil • High rates of malnutrition • Animal food sources rare & expensive • Cultural aversion to use of green leafy vegetables • Require: volunteers, community involvement

  19. Cost effectiveness of VAD preventive programs

  20. Vitamin A deficiency - summary • Vitamin A deficiency is highly prevalent • It has severe consequences especially in the young • Supplementation, fortification and dietary changes have all been used successfully to reduce it’s prevalence • The cost of the programs is not high if integrated into existing child care services

  21. Iodine deficiency (ID) • Iodine must be obtained from the environment • Thyroid hormones, thyroxin and triiodothyronine (T4 &T3) contain 4 and 3 iodine atoms, respectively. • Adults need 100-150 g/daily • Children require less in total, but more per Kg body weight

  22. Iodine deficiency: consequences The following are affected by iodine deficiency: • Thyroid size; enlargement (goiter) • Mental and neuromotor abilities • Reproductive results • Physical growth

  23. Consequences of ID • Neuromotor and cognitive impairment are the most important effects of ID • Where ID is severe and mothers have severe ID, endemic cretinism is found • results include: • cognitive impairment • learning, speech deficits • psychomotor problems

  24. Consequences of ID • Reproductive effects • Rates of reproduction may be lower • Fetal and postnatal survival lower • Motor performance in childhood impaired • Iodine correction in a group of Chinese communities doubled the neonatal survival rates • Other effects

  25. Consequences of ID • Economic effects • no clear evidence available • ID results in lowered energy, lowered learning capacity, increase burden of fetal and postnatal mortality probably interfering with social development • Physical growth • Hypo-thyrodism retards growth and development

  26. Over- correction of ID When ID is severe and there are are thyroid nodules in ID persons, and when iodine treatment is introduced without appropriate control and monitoring, a fraction of the population will develop thyrotoxicosis.

  27. ID prevalenceassessment methods • Goiter rates (*) • Classification of goiters into grades 0, 1 and 2 • ID suspected when >5% of school age children have grade 1 or 2 goiters • Urinary iodine (**) • Can define individual status • Used to define population status • Used to monitor interventions

  28. Prevention of ID-fortification • Salt fortification • Unique in micronutrient supplementation as no dietary changes required • Fortified product more expensive • Social marketing to create demand • Mass media campaigns • Universal salt iodization is the goal • Level of fortification 25-50 mg iodine/Kg

  29. ID prevention-supplementation • Drops and tablets • Original study showing that iodine prevents goiter used sodium iodide tablets given to school children twice per year • Lugol’s solution also used in classrooms • Iodinated oil • Iodinated poppy seed oil - New Guinea • Intra-muscular or oral routes • Well accepted • Costly due to delivery teams required

  30. ID National Programs Ecuador • 1957-58 National survey showed high prevalence rates of goiter and cretinism • 1984 joint enterprise between government and Belgium government agencies started • Local trained teams • Data collection systems

  31. ID National Programs Nigeria • Moderate deficiency • All salt imported, 3 companies • The largest company reported that by 1995, 97% of salt was iodized • The company promoted the iodized salt sale

  32. ID National Programs Bolivia • Landlocked country • 1981 survey showed goiter prevalence of 68.1% • National program started with the formation of a government agency in early 1980’s • Help provided by the Italian govt. • Iodinated oil used to reach >1.4 million persons

  33. ID National Programs Europe and North America • Iodized salt universally available • Mass media campaign • Medical education • Nutrition education • Cooperation of industry • Iodine deficiency nearly non existent

  34. Iodine deficiency - summary • Iodine deficiency occurs in geographic clusters • It results in severe mental and physical disability • It can be virtually eliminated by national supplementation programs • Correction of ID should be performed with close monitoring to prevent adverse reactions

More Related