Dietary deficiencies among families of air warriors: Use of iron deficiency anemia as an index

INTRODUCTION

Anemia is a global health problem affecting the developing countries with major consequences on human health. The World Health Organization (WHO) has estimated that globally 1.62 billion people are anemic, the highest prevalence of anemia being among preschool children (47.4%).^[1]

Anemia is a severe public health problem in India. The National Family Health Survey done in 2015–2016 revealed that 58.6% of preschool children aged 6–59 months were anemic (hemoglobin [Hb] <11.0 g/dl). The most common cause of anemia in this age group was iron deficiency.^[2]

Iron deficiency anemia is disproportionately concentrated in low socioeconomic groups.^[3] Observationally, it was noticed at an Air Force station that preschool children of air warriors had nutritional anemia at levels similar to those seen in lower socioeconomic groups. This prompted three questions. First, was this a serendipitous observation or an actual trend? Second, if the answer to the first question is yes and air warriors have a good socioeconomic status,^[4] why then do they have trends similar to those from a poor socioeconomic stratum? Third, what is the way forward to ensure adequate nutrition amongst air warriors and their families?

MATERIAL AND METHODS

This cross-sectional observational study was conducted at the department of pathology and pediatrics at a multispecialty hospital at an Air Force station in Uttar Pradesh. Ethical clearance was sought as per the norms of the institution. Children of air warriors, aged 6–59 months, who were diagnosed to have iron deficiency anemia were included in the study. However, those with comorbidities such as hemoglobinopathies, chronic liver disease, chronic renal disease, leukemia, tuberculosis, or nephritic syndrome were excluded from the study.

The children were diagnosed of anemia based on the WHO criteria for this age group.^[5] Iron deficiency was diagnosed based on age-specific cutoff values for serum ferritin.^[6] In cases where the children suffered from acute infections, serum total iron-binding capacity (TIBC) was considered as the criterion for diagnosing iron deficiency since serum ferritin is an acute-phase reactant.

A detailed history including perinatal history, associated illnesses, pica, and passage of worms in stools was obtained. Emphasis was laid on dietary history, especially the relative quantity of milk and supplementary feeds given to the children. Based on the dietary history, indicators for assessing infant and young child feeding practices were calculated as follows:^[2]

Minimum meal frequency was defined in breastfed and nonbreastfed children of 6–23 months age, who had received solid or semi-solid foods (including milk feeds for nonbreastfed children). Minimum required meal frequency was defined as 2 solid/semisolid meals per day for breastfed infants who were 6–8 months old and 3 meals per day for breastfed children of 9–23 months age. For children who were not breastfed, receiving solid or semi-solid food or milk feeds at least 4 times a day were considered the minimum requirements.

Minimum dietary diversity was defined in children of 6–23 months age as having received food from 4 or more food groups during the previous day. The food groups used for the calculation of this indicator were as follows:

1. Infant formula, milk other than breast milk, cheese, or yogurt or other milk products

2. Foods made from grains or roots, including porridge or gruel, fortified baby food

3. Vitamin A-rich fruits and vegetables

4. Other fruits and vegetables

5. Eggs

6. Meat, poultry, fish, shellfish, or organ meats

7. Beans, peas, lentils, or nuts

8. Foods made with oil, fat, ghee, or butter.

Minimum acceptable diet was considered achieved if the minimum dietary diversity and the minimum meal frequency had been achieved.

With informed consent of the parents or guardians, samples were drawn for the assessment of hematological parameters such as Hb, mean corpuscular volume, mean corpuscular hemoglobin (MCH), MCH concentration, reticulocyte count, and differential leukocyte count.

The hematological parameters were assessed using automated hematology analyzer (Beckman Coulter LH 750). The serum iron and TIBC estimation (Coral, Tulip) were done using semi-automated biochemistry analyzer. Serum ferritin (Calbiotech) was estimated by ELISA method.

High-performance liquid chromatography for Hb was done to rule out hemoglobinopathies in cases where reticulocyte count was high or Mentzer index was low (MI <12).^[6]

RESULTS

Twenty-seven children fulfilled the inclusion criteria and formed the study population. All mothers had received iron supplementation during the antenatal period and none of the children were diagnosed of anemia before 6 months of age. About 97% of the children were born at term and 25.9% of children had low birth weight. 11.1% of children were found to be underweight.

The frequency distribution of iron deficiency anemia with age is shown in Table 1. 74.1% of cases belonged to the age group of 6–23 months (infants and young children). The mean Hb of the study population was 8.75 g/dl (95% CI 8.15–9.35). For age group 6–23 months, the mean Hb was 8.3 g/dl (95% CI 7.6–8.99) as compared to age group 24–59 months where the mean Hb was 9.96 g/dl (95% CI 9.43–10.49). The difference between mean Hb of these two age groups was statistically significant by Mann–Whitney U-test (P = 0.028).

All the cases of severe anemia belonged to the age group of 6–23 months while 73.3% of those with moderate anemia were infants and young children. A significant positive correlation was observed between Hb and age (ρ = 0.54, P = 0.003).

While assessing the serum iron indices, it was observed that all children had presented with associated acute infection, 48.1% of which was respiratory tract infection. Serum ferritin was found to be raised in 25.9%, normal in 29.6%, and low in 44.5% of the cases. However, serum TIBC was raised in all the cases while serum iron was low in 11 (40.74%) of the cases.

About 11.1% of children had eosinophilia. No child had associated complaints of passing worms in stools. Pica was observed in 14.8% of children. There was no correlation observed between pica and occurrence of eosinophilia.

The diet of these children was studied in detail. About 81.5% of children were exclusively breast fed till 6 months of age. The mean Hb of such children was 8.89 g/dl (95% CI 8.21– 9.57) as compared to children not on exclusive breast milk where the mean Hb was 8.14 g/dl (95% CI 6.75–9.53). There was no statistically significant difference observed between the two means by Mann–Whitney U-test.

Complementary feeding was started in 88.8% of children in the study by 7 months of age. The types of complementary feeds received in the past 24 h are shown in Table 2. In the age group of 6–23 months, the minimum dietary diversity was observed in 11.1%, minimum acceptable diet in 5.5%, and minimum meal frequency in 22.2% of the children.

About 75% of children of age group 6–23 months were started on cow’s milk at the time of weaning. The average amount of cow’s milk consumed in a day was 0.7 L in this age group. Multivariate correlation analysis in the age group of 6–23 months between Hb, age, quantity of cow’s milk consumed per day, and the number of solid meals received in a day was done, as shown in Table 3. Age showed statistically significant positive correlation with Hb (ρ = 0.762). On the other hand, a statistically significant negative correlation was observed between cow’s milk quantity given per day and Hb (ρ = ‒0.77). A significant negative correlation was found between quantity of cow’s milk and variables such as age and solid meals taken per day (ρ = ‒0.553 and ‒0.526, respectively). In multiple linear regression analysis with Hb as the dependent variable, significant association remained with quantity of cow’s milk and age, as given in Table 4. Hb showed an inverse association with quantity of cow’s milk consumed per day and a positive association with age.

DISCUSSION

Anemia is a prevalent public health problem in preschool children belonging to lower socioeconomic strata due to poor sanitary conditions, malnourishment, and poor educational status of mothers. Usually, these factors are mitigated in the families belonging to the middle socioeconomic stratum, in which the present study was performed. Anemia and its severity were found to be disproportionately distributed among the infants and young children (age group 6–23 months) hailing from air warriors’ families. Considering the uniqueness of the situation, we evaluated dietary factors which might have contributed to iron deficiency in these children.

Poor dietary practices while receiving complementary feeds were a constant finding in this cohort. About 75% of these children consumed cow’s milk as major constituent of their diet; the average daily consumption being 0.7 L. Increasing quantity of cow’s milk consumed was associated with a decrease in Hb as brought out in linear regression analysis [Table 4]. Copious consumption of cow’s milk had probably resulted in a decreased solid meal frequency and dietary diversity. In addition, bovine milk proteins are known to be potent inhibitors of iron absorption because of which only 10% of iron is absorbed from cow’s milk as compared to breast milk (50%).^[7] Insufficient intake of iron rich foods, poor bioavailability of iron, and consumption of iron absorption inhibitors had probably made these infants and young children vulnerable to iron deficiency.

Although most of the children were started with complementary feeds by 7 months, the minimum dietary diversity was lacking in 88.9% of the cases. The most common solid food provided in the past 24 h was khichdi which is a poor source of iron. None of the children had consumed iron-rich food such as meat, organ meats, fish, or poultry.^[2] Thus, apart from cow’s milk, the solid meals received by the children were also deficient in iron.

About 74.1% of cases of anemia were found in the children of age group 6–23 months with the severity of anemia reducing as the age advanced as brought out in the linear regression analysis [Table 4]. A recent Indian survey has shown that as the children grow older, their diet transitions from being predominantly milk based on a more diverse micronutrient-rich diet.^[2] Consequently, as the age progressed, the dominance of cow’s milk in the diet was diminished along with its undesirable effects.

It was ironical that this high rate of anemia was observed despite no other known risk factors of iron deficiency anemia such as maternal iron status and period of gestation^[8] playing a part, since all mothers had received iron supplementation during the antenatal period and none had suffered from severe anemia during pregnancy. About 97% of the children in the study population were born at term. Exclusive breastfeeding which protects against iron deficiency in the first 4–6 months of life^[2,7,9] was a prevalent practice in this population. None of the children were diagnosed of anemia before 6 months of age.

The ferritin levels in the present study showed high variability and was found to be low in only 44.5% of the children. Coexisting acute illnesses were present in all the children. Serum ferritin is an acute-phase reactant and is increased in inflammation which leads to an underdiagnosis of iron deficiency in such cases.^[10] In such a scenario, an alternative indicator for iron deficiency is needed to be sought. TIBC was found to be a reliable diagnostic marker for iron deficiency in this study. Serum iron, TIBC, and related indices should be relied on before completely ruling out iron deficiency in children presenting with anemia along with acute infection, especially if ferritin is normal or raised.

CONCLUSION

In summary, children of air warriors were found to be anemic, despite them having an adequate socioeconomic status and resources. The associated factors in this population were high reliance on cow’s milk as a complementary food and poor dietary diversity. At the same time, the study indicated adequate antenatal care, and the children starting off with no deficiency at birth. The study brings out the need for dietary counseling for air warriors and their families to ensure better health and lower disease burden.