Validity of using capillary blood for the measurement of plasma ferritin

A food synergy approach in a national program to improve the micronutrient status of preschoolers: a randomized control trial protocol

Iron deficiency anemia (IDA) is a significant public health issue in India affecting nearly all vulnerable segments of the population. Causes of IDA include low consumption of iron-rich foods combined with poor iron bioavailability of nonheme iron sources. To date, interventions aimed at correcting IDA focus on increasing iron intake through iron supplementation or fortification strategies. In contrast, dietary diversification is a long-term sustainable approach to improve bioavailable iron intake. In this context, the inclusion of vitamin C-rich fruits in the regular diet has proven to improve iron absorption, but the effect on iron status is inconclusive. Considering the ongoing national program for preschoolers in India, we designed a cluster randomized controlled trial (RCT) to test the hypothesis that inclusion of vitamin C-rich fruit in a regular meal would improve iron absorption and lead to better child iron and micronutrient status, cognitive development, gut health, and growth while reducing morbidity. This paper illustrates a context-specific framework and activities to design and functionalize an open-label, three-arm cluster RCT to test a specific hypothesis. The results of this designed trial should generate evidence to inform policy on the effect of a food-based intervention on iron status.

Exploring the bio-behavioural link between stress, allostatic load & micronutrient status: A cross-sectional study among adolescent boys

Background & objectives:

Allostatic load (AL) is a cumulative measure of physiological deregulation and is influenced by multiple factors including nutrition. The objectives of the study were to assess AL among adolescent boys (15-19 yr) and delineate its association with psychological stress and micronutrient status.

Methods:

A cross-sectional, school-based study was conducted among 370 adolescent boys of five higher secondary schools from Hyderabad, India. Perceived stress, adolescent life event stress (ALES), psychological morbidity and coping were measured. Biomarkers of AL included dehydroepiandrosterone sulphate, 12-h urinary cortisol, interleukin-6, C-reactive protein, lipid profile, body mass index and blood pressure. Micronutrient status with respect to iron (haemoglobin, ferritin, hepcidin, soluble transferrin receptor), folate, vitamins B12, C and A were analyzed in a sub-sample of 146 boys. AL score ≥3 was calculated from eight biomarkers.

Results:

Fourteen per cent participants had no AL but 34.3 per cent had AL score of ≥ 3. Unadjusted means of ALES scores were significantly different (P = 0.045) among participants with low [mean, 95% confidence interval (CI): 580, 531-629] and high (663, 605-721) AL. After controlling for confounders, the means were significantly different for controllable life event sub-scale of ALES (P = 0.048). Adjusted hepcidin concentrations were significantly higher among participants with high AL (means, 95% CI, 27.2, 24.0-30.8 for high AL; 22.1, 20.2-24.2 μg/l for low AL, P = 0.014).

Interpretation & conclusions:

Build-up of AL was found in adolescent boys and was positively associated with life event stress. Iron nutrition and stress exhibited a positive association through hepcidin. The study provides a link between iron nutrition, physiological deregulation and stress.

Characterisation of anaemia and associated factors among infants and pre-schoolers from rural India

Objective

In India, national databases indicate anaemia prevalence of 80 % among 6–35-month-old children and 58 % among 36–59-month-old children. The present study aimed to characterise anaemia and the associated factors among infants and pre-schoolers living in rural India.

Design

Multivariate logistic regression analysis of data collected prior to an intervention trial. Fe-deficiency with anaemia (IDA), Fe deficiency with no anaemia (IDNA) and anaemia without Fe deficiency were defined. Serum ferritin, soluble transferrin receptor (sTfR) and sTfR/log ferritin index were used to indicate Fe status.

Setting

Twenty-six villages of Nalgonda district, Telangana, India. Data were collected in community sites.

Participants

Four hundred and seventy-six infants (aged 6–12 months), 316 pre-schoolers (aged 29–56 months) and their mothers.

Results

Prevalence of anaemia among infants and pre-schoolers was 66·4 and 47·8 %, prevalence of IDA was 52·2 and 42·1 %, prevalence of IDNA was 22·2 and 29·8 %, prevalence of anaemia without Fe deficiency was 14·2 and 5·7 %. Among infants, anaemia was positively associated with maternal anaemia (OR=3·31; 95 % CI 2·10, 5·23;P<0·001), and sTfR/log ferritin index (OR=2·21; 95 % CI 1·39, 3·54;P=0·001). Among pre-schoolers, anaemia was positively associated with maternal anaemia (OR=3·77; 95 % CI 1·94, 7·30;P<0·001), sTfR/log ferritin index (OR=5·29; 95 % CI 2·67, 10·50;P<0·001), high C-reactive protein (OR=4·39; 95 % CI 1·91, 10·06,P<0·001) and young age (29–35 months: OR=1·92; 05 % CI 1·18, 3·13,P=0·009).

Conclusions

Anaemia prevalence continues to be high among infants and pre-schoolers in rural India. Based on sTfR/ferritin index, Fe deficiency is a major factor associated with anaemia. Anaemia is also associated with inflammation among pre-schoolers and with maternal anaemia among infants and pre-schoolers, illustrating the importance of understanding the aetiology of anaemia in designing effective control strategies.

Adolescent life-event stress in boys is associated with elevated IL-6 and hepcidin but not hypoferremia

OBJECTIVE

The link between stress-related increases in inflammatory markers, hepcidin, and iron status are poorly understood, especially in developing countries like India. The aim of the study was to examine the relationship between adolescent life-event stress (ALES), inflammatory markers, and its association with hepcidin and biomarkers of iron status among adolescent boys.

METHODS

Data pertaining to a subsample of 145 participants from a cross-sectional, school-based study recruiting 370 adolescent boys aged 15-19 years, from 5 schools in Hyderabad, India, were analyzed. Stress was assessed using the ALES scale, psychological distress by the General Health Questionnaire-2 (GHQ-12), and approach and avoidance coping using the Coping Strategies Scale. Biomarkers of iron and concentrations of other micronutrients, hepcidin, IL-6 and C-reactive protein (CRP) in plasma were analyzed. Data were subjected to regression, path analyses, and analysis of covariance (ANCOVA).

RESULTS

ALES was a significant predictor of interleukin (IL)-6 (β = 0.196, p = 0.012), CRP (β = 0.217, p = 0.010), and log hepcidin (β = 0.228, p = 0.006). Hepcidin correlated significantly (p < 0.001) with IL-6 (r = 0.344) and CRP (r = 0.370) but not with the biomarkers of iron status. Path analysis showed that the model had an acceptable fit, with a root mean square error of approximation of 0.019, 90% confidence interval (CI) of 0.00-0.074, comparative fit index of 0.988, chi-square p = 0.393, and chi-square/df of 1.053.

CONCLUSIONS

Adolescent life-event stress is associated with elevated IL-6 and hepcidin concentration but not hypoferremia. These findings may help in iron supplementation programs for tackling anemia.

Inclusion of guava enhances non-heme iron bioavailability but not fractional zinc absorption from a rice-based meal in adolescents

Assessing the bioavailability of non-heme iron and zinc is essential for recommending diets that meet the increased growth-related demand for these nutrients. We studied the bioavailability of iron and zinc from a rice-based meal in 16 adolescent boys and girls, 13-15 y of age, from 2 government-run residential schools. Participants were given a standardized rice meal (regular) and the same meal with 100 g of guava fruit (modified) with (57)Fe on 2 consecutive days. A single oral dose of (58)Fe in orange juice was given at a separate time as a reference dose. Zinc absorption was assessed by using (70)Zn, administered intravenously, and (67)Zn given orally with meals. The mean hemoglobin concentration was similar in girls (129 ± 7.8 g/L) and boys (126 ± 7.1 g/L). There were no sex differences in the indicators of iron and zinc status except for a higher hepcidin concentration in boys (P < 0.05). The regular and modified meals were similar in total iron (10-13 mg/meal) and zinc (2.7 mg/meal) content. The molar ratio of iron to phytic acid was >1:1, but the modified diet had 20 times greater ascorbic acid content. The absorption of (57)Fe from the modified meal, compared with regular meal, was significantly (P < 0.05) greater in both girls (23.9 ± 11.2 vs. 9.7 ± 6.5%) and boys (19.2 ± 8.4 vs. 8.6 ± 4.1%). Fractional zinc absorption was similar between the regular and modified meals in both sexes. Hepcidin was found to be a significant predictor of iron absorption (standardized β = -0.63, P = 0.001, R(2) = 0.40) from the reference dose. There was no significant effect of sex on iron and zinc bioavailability from meals. We conclude that simultaneous ingestion of guava fruit with a habitual rice-based meal enhances iron bioavailability in adolescents.

Psychometric validation of a knowledge questionnaire on micronutrients among adolescents and its relationship to micronutrient status of 15-19-year-old adolescent boys, Hyderabad, India

OBJECTIVE

To develop a psychometrically valid questionnaire for testing knowledge on micronutrients and to assess the relationship between knowledge and biomarkers of micronutrient status among adolescents.

DESIGN

Cross-sectional, institution-based, validity and reliability study.

SETTING

Seven higher secondary schools were covered in the limits of Greater Hyderabad Municipal Corporation, Hyderabad, India.

SUBJECTS

Students aged 15-19 years, n 92 for the pre-test, n 108 for test-retest and n 109 for studying the relationship between knowledge and biomarkers of Fe, retinol, ascorbic acid, α-tocopherol, folic acid and vitamin B12 status.

RESULTS

From an item pool of 106, thirty-one items were selected based on content validity. Statistical tools to obtain a valid and reliable questionnaire among adolescent boys and girls resulted in eighteen items with a difficulty index of 0·11-0·86, discrimination index of 0·20-0·72 and validity index (point bi-serial correlation) of 0·10-0·62. Reliability as measured by Cronbach's α was 0·71 and the intra-class correlation coefficient was 0·80. A Bland-Altman plot showed good agreement between test and retest scores. The mean response score to the eighteen-item questionnaire was 5·2 (sd 2·68). The mean values of serum retinol were significantly different (P = 0·022) between groups below (24·8 (sd 6·64) μg/dl) and above (28·0 (sd 7·67) μg/dl) the 50th percentile of knowledge score. The relationship persisted after controlling for economic status as a covariate using analysis of covariance (P = 0·018). Other micronutrients did not show any significant relationship.

CONCLUSIONS

A valid and reliable eighteen-item knowledge questionnaire was constructed and found to have a significant positive relationship with plasma retinol status alone.

Micronized ferric pyrophosphate supplied through extruded rice kernels improves body iron stores in children: a double-blind, randomized, placebo-controlled midday meal feeding trial in Indian schoolchildren

BACKGROUND

Micronized ferric pyrophosphate (MFPP) in extruded rice kernels mixed in a rice-based meal could be an effective strategy for improving iron status of children in India.

OBJECTIVE

The objective was to determine the impact of MFPP supplied through extruded rice kernels in a rice-based meal on iron status of children participating in the midday meal (MDM) scheme in India.

DESIGN

The sensory characteristics of cooked rice containing MFPP in extruded rice kernels, in vitro availability, and loss of iron during cooking from a typical MDM consisting of 125 g rice (dry weight) containing 19 mg Fe [fortified rice (FR); normal rice mixed with Ultra Rice (extruded kernels containing MFPP of ∼3.14-μm mean particle size)] in comparison with unfortified rice (UFR) were tested. A double-blind, 8-mo, placebo-controlled trial was conducted in 5-11-y-old schoolchildren (n = 140) who were randomly assigned to receive either an FR-MDM or a UFR-MDM. Average consumption amounts of the MDM, height, weight, hemoglobin, ferritin, and C-reactive protein were measured at baseline and at 8 mo.

RESULTS

The sensory qualities of cooked FR and UFR were similar. The in vitro iron availability from FR-MDM (1.3%) was significantly (P < 0.05) lower than that from UFR-MDM (3.3%). Providing FR-MDM to the schoolchildren for 8 mo improved ferritin significantly (P < 0.001), by 8.2 ± 2.10 μg/L. However, the increase in hemoglobin was similar between groups (FR: 0.99 ± 0.10 g/dL; UFR: 1.15 ± 0.10 g/dL), which suggests that other factors beyond additional iron intake had a large influence on hemoglobin concentration. The prevalence of iron deficiency decreased significantly (P < 0.05) in the FR group (33-14%) and increased marginally in the UFR group (31-37%). The prevalence of anemia and iron deficiency anemia was similar between groups at baseline and at 8 mo.

CONCLUSION

Regular intake of 19 mg Fe/d in MFPP supplied through extruded rice kernels improves iron stores and reduces iron deficiency among schoolchildren in India.

Effect of micronutrient supplement on health and nutritional status of schoolchildren: biochemical status

OBJECTIVE

We assessed the effect of a daily intake of a micronutrient-fortified beverage for 14 mo on indicators of biochemical status of important micronutrients in schoolchildren.

METHODS

A double-blind, placebo-controlled, matched-pair, cluster, randomization study design was used. Biochemical indicators of micronutrient status were evaluated at baseline and at the end of 14 mo on a subsample in nine matched pairs. Prevalence (percentage) of subclinical deficiency, mean, and mean increments of each indicator were compared between supplemented and placebo groups.

RESULTS

Extent of inadequacy at baseline was more or less 100% for folic acid, 65% for vitamins B2 and B6, and 55% for vitamins C and A. Prevalence of anemia among subjects was 55%, with inadequacy of vitamin B12 being 40% and that of vitamin D being 30%. No subject had inadequacy of iodine based on urinary iodine. Supplementation of a micronutrient-enriched beverage for 14 mo significantly improved the status of many of the nutrients. The effect was significant with respect to vitamins A, B2, and B12, folic acid, vitamin D, parathyroid hormone, and thyroid-stimulating hormone in children who received the supplement compared with those who received only placebo. Hemoglobin status improved only in children who had anemia in the supplemented group.

CONCLUSIONS

Prevalence of multiple subclinical micronutrient deficiencies are high in middle-income Indian school children. Daily consumption of a micronutrient-enriched beverage had positive effects that were confined to those nutrients that were inadequate at baseline.

Response of hemoglobin, serum ferritin, and serum transferrin receptor during iron supplementation in pregnancy: a prospective study

OBJECTIVE

We evaluated the effect of iron supplementation on biochemical indicators of iron status, namely hemoglobin (Hb), serum ferritin (SF), and serum transferrin receptor (sTfR), during pregnancy.

METHODS

A prospective study was conducted in 73 pregnant women who received daily supplements of 60 mg of iron and 500 microg of folic acid for 100 d from 19 wk of gestation. The indicators of iron status (Hb, SF, and sTfR) at 19, 27, and 35 wk of gestation were analyzed. The response of iron status indicators to iron supplementation was assessed in the cohort and in pregnant women who were anemic (n = 35) and non-anemic (n = 38) at 19 wk.

RESULTS

All three indicators of iron status during supplementation (27 and 35 wk) were similar to the presupplementation status. The sTfR as an indicator correlated negatively with presupplementation Hb levels (r = -0.417). Based on sTfR level in iron-adequate pregnant women, a cutoff value of at least 12.0 mg/L was derived to define iron deficiency in pregnancy. When the response was tested in anemic pregnant women, iron supplementation improved mean Hb (P < 0.05) at the end of 35 wk (96 +/- 8.8 to 110 +/- 20.2 g/L) of gestation, with no change in SF. Conversely, non-anemic pregnant women showed a significant increase in SF and a decrease in Hb (122 +/- 11.6 to 112 +/- 15.2 g/L) at 35 wk of gestation. A significant effect of iron intake on sTfR was seen only among iron-deficient anemic women.

CONCLUSIONS

These observations suggest that, during pregnancy, sTfR responds to iron supplementation when there is iron-deficiency anemia and therefore can be used as an indicator.

Serum transferrin receptor in children with respiratory infections

OBJECTIVE

To study the effect of infection on iron status in children suffering from acute, mild or severe respiratory infections and to determine the nature of anemia in infection using serum transferrin receptor (sTfR) levels.

DESIGN

Forty-three children aged between 3 and 5 y with no evidence of infection and receiving iron supplements in the preceding 100 days served as controls. Twenty-one children with mild upper respiratory infection and 94 children hospitalized for acute pneumonia constituted the experimental group. Hemoglobin (Hb), sTfR and serum ferritin were estimated in all the children at the time of diagnosis and again on the 15th and 30th days after the infection in those who were available for follow-up.

RESULTS

Mean (95% CI) sTfR was 6.08 (5.1-7.1) mg/l in healthy non-anemic children. Upper respiratory infection had no impact on Hb or sTfR but it significantly elevated serum ferritin levels. Eighty-three percent of the children with pneumonia had Hb less than 110 g/l at the time of diagnosis and had elevated mean sTfR, 18.0 (15.7-20.3) mg/l. There was a decline in mean sTfR by the 15th day of infection to 14.3 (11.3-17.4) mg/l with further rise to 22.9 (13.0-31.9) mg/l by 30 days. Serum ferritin was significantly elevated at the time of diagnosis (85.9; 71.1-100.8 micro g/l) as well as at 15 days (89.1; 68-110.1 micro g/l) with a decline by 30 days.

CONCLUSIONS

Severe lower respiratory infection exaggerates iron-deficient erythropoiesis by blocking release of iron from the storage pools. sTfR may not be a sensitive and specific tool of assessing true iron status of children exposed to severe infections.

A case study of nutrient intervention of oral precancerous lesions in India

Tobacco chewing and/or smoking are strongly related to several cancers, mainly of the upper aerodigestive tract. Several studies on diet and cancer links suggest that micronutrients, particularly antioxidant vitamins and minerals, are risk modifiers of cancers of epithelial origin. This study looks at the impact of micronutrients such as vitamin A, riboflavin, zinc and selenium as intervention agents in subjects with and without precancerous lesions in a high risk group (reverse smokers of chutta-rolled tobacco leaf). Reverse smokers from four villages were enrolled in the study. 150 subjects were supplemented with four nutrients, namely vitamin A, riboflavin, zinc and selenium in the form of a capsule twice a week for 1 year. 148 controls received a placebo capsule containing lactose for the same period. Clinical history and anthropometric data were collected from all the subjects and a clinical photograph of the palate was taken. Micronutrients were estimated in random blood collected from a sub-sample before and after the study. Micronutrients improved the vitamin A, riboflavin and selenium nutriture in the supplemented group with a concomittant regression of precancerous lesions present on the palate. Clinically complete remission of white, red and combination lesions was seen in 57% of subjects on supplements whereas 8% on placebo showed a positive response. Further progression of these lesions was seen in 10% of the supplemented group compared with 47% in the placebo group (P < 0.001). In the non-lesion group, new lesions appeared in 12% on supplements while more than 38% on the placebo developed new lesions (P < 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

Iron nutritional status of preschool children

Low hemoglobin and low MCHC levels were indicative of high incidence of iron deficiency in preschool children. The extent of iron deficiency as assessed by serum ferritin and free erythrocyte protoporphyrin showed a different trend. While FEP levels were highly suggestive of extensive iron deficiency (in 40-45% of children below the age of 5 years), low serum ferritin was seen in only 16-20% of children. The discrepant finding of high serum ferritin, and high erythrocyte protoporphyrin despite low MCHC in the present study, possibly reflects iron deficiency status along with chronic infection resulting in hyperferritinemia and hyperprotoporphyrinemia. It may be also due to associated folate deficiency resulting in non utilization of iron leading to the elevated levels of protoporphyrin.