Normal haematological values in the Central American population

Haematological Status of Preschool and School-Age Children in Urban and Rural Areas of Guatemala

We studied the prevalence of low haematocrit values (defined as <38%) in 1,253 children from urban and rural areas of Guatemala, to examine any urban-rural or age-related trends. Though the crude prevalences of low haematocrit for all the children showed a significant difference between urban and rural residents, the significance disappeared when these values were adjusted for differences in the age profiles of the two groups. As expected, preschool children had significantly more low haematocrits (32.0%) than school-age children (6.0%) (p < .05). Ferritin levels were available for 35.9% of the preschool children (one urban and one rural location); of these, 51.8% had levels below 12 mg/l, indicating iron deficiency. These values were used to determine the predictive value of haematocrit compared with ferritin values, and the cut-off at which haematocrit reaches optimum sensitivity and specificity to diagnose iron depletion. A cut-off of 39% had a sensitivity of 61% and a specificity of 45% in urban preschoolers, and a cut-off of 38% had a sensitivity of 75% and specificity of 42% in rural preschoolers.

Hematocrit and Hemoglobin Levels of Nonhuman Apes at Moderate Altitudes: A Comparison with Humans

Mortola, Jacopo P. and DeeAnn Wilfong. Hematocrit and hemoglobin levels of nonhuman apes at moderate altitudes: a comparison with humans. High Alt Med Biol. 17:323-335, 2016.-We asked to what extent the hematologic response (increase in hematocrit [Hct] and in blood hemoglobin concentration [Hb]) of humans to altitude hypoxia was shared by our closest relatives, the nonhuman apes. Data were collected from 29 specimens of 7 species of apes at 2073 m altitude (barometric pressure Pb = 598 mm Hg); additional data originated from apes located at a lower altitude (1493 m, Pb = 639 mm Hg). The human altitude profiles of Hct and Hb between sea level and 3000 m were constructed from a compilation of literature sources that (all combined) comprised data sets of 10,000-12,000 subjects for each gender. These human data were binned for 0-250 m altitude (sea level) and for each 500 m of progressively higher altitudes. Values of Hb and Hct of both men and women were significantly higher than at sea level at the 1500 bin (1250-1750 m); hence, the altitude threshold for the human hematological responses must be between 1000 and 1500 m. In the nonhuman apes, no increase in Hct or Hb was apparent at 1500 m; at 2000 m, the increase was significant only for the Hb of females. At either altitude in the group of nonhuman apes, the increase in Hct was much less than in humans, and that of Hb was significantly less at 1500 m. We conclude that lack of, or minimal, hematopoietic response to moderate altitude can occur in mammalian species that are not genetically adapted to high altitudes. Polycythemia is not a common response to altitude hypoxia and, at least at moderate altitudes, the degree of the human response may represent the exception among apes rather than the rule.

Anemia, iron deficiency, and stress fractures in female combatants during 16 months

Yanovich, R, Merkel, D, Israeli, E, Evans, RK, Erlich, T, and Moran, DS. Anemia, iron deficiency, and stress fractures in female combatants during 16 months. J Strength Cond Res 25(12): 3412-3421, 2011-The purpose of this study is to evaluate the hematological profile of military recruits in different settings and training programs and to investigate the link between anemia and iron deficiency with stress fracture (SF) occurrence. We surveyed 3 groups of recruits for 16 months: 221 women (F) and 78 men (M) from 3 different platoons of a gender-integrated combat battalion and a control group (CF) of 121 female soldiers from a noncombat unit. Data were fully collected upon induction and at 4 and 16 months from 48F, 21M, and 31CF. Blood tests, anthropometry, physical aerobic fitness, and SF occurrence were evaluated. On induction day, 18.0 and 19.0% of F and CF were found to be anemic, and 61.4 and 50.9%, respectively, were found to have iron deficiency, whereas 7.7% of M were found to be anemic and 10.2% iron deficient. During the 4 months of army basic training (ABT), anemia and iron deficiency prevalence did not change significantly in any group. After 16-months, anemia prevalence decreased by 8% among F and CF and abated in M. Iron deficiency was prevalent in 50.0, 59.4, and 18.8% of F, CF, and M, respectively. Stress fractures were diagnosed in 14 F during ABT, and they had a significantly higher prevalence (p < 0.05) of anemia and iron deficiency anemia compared to F without SFs. The observed link between anemia and iron deficiency on recruitment day and SFs suggests the importance of screening female combat recruits for these deficiencies. To minimize the health impact of army service on female soldiers, preventative measures related to anemia and iron deficiency should be administered. Further research is needed for evaluating the influence of low iron in kosher meat as a possible explanation for the high prevalence of iron deficiency among young Israeli recruits.

INCAP Studies of Hematologic and Gastrointestinal Function in Healthy Individuals and those with Protein–Energy Malnutrition and Infection

Anemia is highly prevalent, especially in poorly nourished populations living in unsanitary conditions. Studies of the Central American population showed that iron was the predominant deficient hematopoyetic micronutrient and that correction of nutrient deficiencies led to hematological normality as defined by WHO. The bioavailability of diverse iron compounds added to the mostly vegetable diets of such populations showed the superior absorption of chelated iron (NaFeEDTA) and its strong effectiveness in correcting iron deficiency when added to sugar. The consequences on development and mental behavioral functions as well as on work capacity of iron deficiency and anemia in infants, children and adults, and the positive effects of their correction was demonstrated. In protein-energy malnourished (PEM) children, the deficit in active tissue mass (basal oxygen consumption) and in total hemoglobin content were closely related. This relationship persisted as the rates of active tissue mass repletion was modified by levels of protein intake. This demonstrated the strong adaptive nature of hemoglobin content in response to oxygen needs in PEM and during recovery.

Gastrointestinal functions in PEM and in populations demonstrated the bacterial invasion of the upper GI tract and how this resulted in secondary bile acids that are toxic to the intestinal mucosal cells impairing their absorptive functions. Environmental hygiene in populations reversed gut bacterial migration and improved GI function.

What is the evidence for gender differences in ferritin and haemoglobin?

Reference ranges for haemoglobin and ferritin in women of reproductive age are widely reported showing values that are lower than equivalent aged males. Similar values would be expected in the absence of different biological requirements. While reference ranges have been derived from data on large populations, it is likely that these populations have included significant numbers of women who are iron deficient in view of menstrual blood loss and poor dietary intake. Populations with a daily iron intake in excess of 100mg have shown that iron deficiency in females is rare. Studies reporting bone marrow with iron stains from 50 years ago pointed out that significant numbers of women were iron deficient and more recently serum ferritin studies have confirmed this. However, a large number of women in the Western world spend a significant part of their lives in a negative iron balance due to a combination of poor diet and menstrual blood loss. The presence of haem iron in the diet of humans enhances non-haem iron absorption but dietary surveys consistently report that women's diet is deficient in iron. Furthermore, the typical Western diet contains many common foods that limit iron absorption. It appears that lower haemoglobin and ferritin values in menstruating women have been accepted as normal rather than possibly representing widespread iron deficiency. Reference ranges should be re-evaluated in populations proven to be iron replete.

Factors associated with Hb concentration in children aged 6-59 months in the State of Pernambuco, Brazil

In 1997, the prevalence of anaemia was 40.9 % among children aged 6-59 months in the State of Pernambuco, north-east Brazil. Using the same sample of children, we have investigated possible reasons for this high prevalence. A representative sample was selected through a three-stage process: proportional systematic random sampling of municipalities in the State, systematic random sampling of census sectors within these municipalities, and finally, simple random sampling of households with children aged 6-59 months to obtain the sample of 650 children. Data collection included demographic, environmental, socio-economic and maternal variables, and nutritional status and dietary intakes of the children. Multiple linear regression analysis was based on a hierarchical model of factors associated with Hb concentration. The mean Hb concentration of children aged 6-23 months was 10 g/l lower than that of older children. In the regression analysis, child age explained 8.3 % of the variance in Hb concentration. The intake of bioavailable Fe explained a further 3.3, serum retinol 2.7, diarrhoea 2.4, water treatment 1.7, sanitation 1.3 and low birth-weight 0.5 %. The final model explained 23.4 % of the variance in Hb concentration. We conclude that child age, bioavailable-Fe intake, serum retinol concentration, diarrhoea, water treatment, sanitation and low birth-weight are independently associated with Hb concentration. In north-east Brazil, anaemia prevention programmes among children should focus on those aged <2 years and should consider feasible strategies to improve intakes of bioavailable Fe and vitamin A, and reduce infection. Supplemental Fe should be given to low birth-weight infants.

Long-term weekly iron supplementation improves and sustains nonpregnant women's iron status as well or better than currently recommended short-term daily supplementation

This 7-mo double-blind study compared the efficacy of two iron supplementation schemes in improving iron nutrition among 116 healthy fertile-age women. They were randomly distributed in three groups, receiving: Group 1, iron + folate (60 mg and 250 microg, respectively) daily for 3 mo (currently recommended scheme), and folate (250 microg) weekly the subsequent 4 mo. Group 2, folate daily, and 60 mg iron only once weekly for 3 mo, and then weekly iron + folate for 4 mo. Group 3, folate daily for 3 mo and then weekly for 4 mo. At baseline, 16% had depleted stores (plasma ferritin <15 microg/L) and 16% had hemoglobin levels <125 g/L. Eight percent had hemoglobin levels <120 g/L. In Group 1 hemoglobin and ferritin increased at 3 mo but returned to near basal conditions after 4 mo of weekly folate. In Group 2, hemoglobin and ferritin increased progressively throughout the 7 mo but mostly after 3 mo. Group 3 did not change. Side effects were highest with daily iron. Weekly iron supplementation over 7 mo (30 doses) improved and sustained iron nutrition at least as effectively and was better tolerated than 90 daily iron supplements consumed during 3 mo.

Iron supplementation for the control of iron deficiency in populations at risk

Iron supplementation, mostly with a therapeutic orientation, has been a key strategy for the short-term control of iron deficiency and ferropenic anemia. It has been used almost exclusively in antenatal clinics, but in spite of its confirmed efficacy in supervised trials, it has proven ineffective in practice in most developing countries. Poor effectiveness has been attributed to various factors including insufficient dose and time of supplementation and poor adherence. These problems have led to the administration of high iron doses, which have proven equally ineffective in practice. This paper introduces four concepts: (1) that iron supplementation targeted to pregnant women should cover the full reproductive cycle, from prepregnancy to at least the end of lactation instead of only the pregnant women; (2) that entering pregnancy with iron deficiency contributes to the failure of antenatal iron supplementation and that prepregnancy iron reserves increase the effectiveness of antenatal supplementation; (3) that medium- to long-term weekly ingestion of proper iron-folate supplements, with a preventive aim and directed to all risk groups, should be community based rather than health service based but supervised by the latter (in this sense, preventive supplementation is equal to targeted iron fortification); and (4) that preventive supplementation, based on weekly dosing, has proven efficacious. Problem-oriented research to evaluate the sustainability and medium- to long-term efficacy of these concepts is called for. The bases for the concepts and suggestions are summarized in this paper.

Alteration of circulating micronutrients with overt and occult infections in anaemic Guatemalan preschool children

Clinical and laboratory data to define conditions of apparent health, localised infection or inapparent infection were available for 74 anaemic Guatemalan preschool children in the baseline phase of a clinical trial of the effect of iron and vitamin A on haematological status to be correlated with serum levels of four circulating micronutrients--iron, zinc, copper and retinol--known to be influenced by activation of the acute-phase reaction. Upon enrolment, only 29.7% of the children were free of all evidence of infection, 36.5% had one or more localised conditions detected on clinical examination, and 33.8% had an elevated white cell count and/or sedimentation rate, without localising features. These were classified as 'inapparent infections'. With respect to the healthy children, levels of iron, zinc, and retinol declined and copper generally increased in the four categories of clinical infections (acute respiratory infection, dermal infections, conjunctivitis, and 'other') but were also displaced in inapparent infections. Some activation of the acute-phase response in anaemic children may occur in the absence of clinical findings. Care must be taken in interpreting circulating micronutrient levels in relation to nutritional status in such population.

The importance of socioeconomic and nutritional conditions rather than altitude on the physical growth of prepubertal Andean highland boys

The aim of this work was to study the effect of hypoxic stress on the physical growth of prepubertal Bolivian boys (10-11.5 years of age) of the same socioeconomic and nutritional conditions. The subjects consisted of 143 boys living in La Paz (altitude 3600 m, n = 67) and Santa Cruz de la Sierra (altitude 420 m, n = 76). Among the boys studied at high altitude, 23 were from a high socioeconomic background (HA1) and 44 from a low socioeconomic background (HA2). The group studied at low altitude consisted of 47 boys from a high socioeconomic background (LA1) and 29 from a low socioeconomic background (LA2). A scientific evaluation of the nutritional status of the boys was realized from specific anthropometric characteristics (height, body weight, upper arm muscle circumference, body fat mass and body mass index) and haematological (haematocrit, haemoglobin, serum iron, serum ferritin, red cell protoporphyrin, transferrin saturation) and biochemical (total serum protein, albumin and prealbumin) parameters. At high as at low altitudes, the biometric characteristics of boys from a low socioeconomic background were significantly lower than those of boys from a high socioeconomic background. The physical growth of HA2 and LA2 boys was delayed by approximately 2 years. All the boys had biochemical and haematological parameters within the normal range. Boys from a low socioeconomic background were considered as marginally undernourished and those from a high socioeconomic background as well-nourished. Within the same socioeconomic class there was no nutritional difference between highland and lowland boys. Similarly, and this is the most important feature of this study, there was no difference for the overall biometric characteristics between highland and lowland boys of the same socioeconomic and nutritional status. Therefore, it appears that when socioeconomic and nutritional conditions are taken into account, there is no effect of hypoxic stress on the physical growth of prepubertal Andean highland boys.

[Normal hematologic parameters]

Hematological studies by several Brazilian and other Latin-American authors who give parameters considered as normal for different populations have been reviewed. Results showed significant differences, due to social, environmental and nutritional factors as well as to different methodological procedures and also to age, sex, race, occupation and other individual characteristics. Three Brazilian studies were selected in the light of the wide variety of parameters included. Ranges are presented as a demonstration of the variations in such samples, presumably considered "normal" by the respective authors presumably "normal". One of the purposes of the present study is to establish the basis for future investigation into the effects of industrialization on the ranges of the hematological parameters of individuals taken to be normal.

Hemoglobin concentration of pastoral nomads permanently resident at 4,850-5,450 meters in Tibet

This paper presents data on the hemoglobin concentration of a sample of 103 pastoral nomads who are lifelong residents of Phala, at 4,850-5,450 m, on the northern plateau of the Tibet Autonomous Region of the Peoples' Republic of China. This native population resides at the highest altitude of which we are aware and is thus exposed to the most extreme chronic hypoxic stress. However, they do not exhibit the most pronounced physiological adaptations, i.e., hemoglobin concentrations exceeding those found in all other high-altitude populations. Adult male and female mean hemoglobin concentrations of 18.2 and 16.7 gm/dl, respectively, were found. These data, in conjunction with earlier studies of ethnic Tibetans living at 3,400 m, demonstrate a pattern of increasing hemoglobin concentration (erythrocytosis) at increasing altitude of residence in the Himalayas and Tibet. At the same time, however, the hemoglobin concentration is lower than that found among Andean highlanders. These new data raise the possibility of quantitative population differences in hematological adaptation to high altitude hypoxia.

Racial differences in red cell indices

A high prevalence of iron deficiency was found in apparently healthy Asian immigrant children in Harrow. After excluding children with overtly abnormal red cell indices, Asian and European children had identical haemoglobin values, but Asian children had much lower mean cell volume and mean corpuscular haemoglobin values and higher red blood cell values.

[Nutritional anemia in pregnant women attending health centers of the State of São Paulo (Brazil)]

Com o objetivo de estimar a prevalência de anemia entre a clientela do Programa de Atendimento à Gestante (PAG), da Secretaria de Saúde do Estado de São Paulo (Brasil), e de analisar o item referente à suplementação de ferro, do mesmo programa, estudaram-se os prontuários de 4.539 gestantes, matriculadas nos PAGs de 15 Centros de Saúde (CS), escolhidos através de amostragem, probabilística. Observou-se anemia (hemoglobina - Hb - < 11,0 g/dl) em 35,1% das gestantes, valor que sugere constituir essa deficiência problema de saúde pública em relação à clientela dos Centros de Saúde estudados. É destacada a necessidade de incluir, na rotina do PAG, a medida da concentração de Hb e de referi-la conjuntamente com a idade gestacional propiciando conhecer a necessidade de ferro suplementar específica de cada grávida, aumentando, com isso, a eficiência do programa de combate à anemia e, conseqüentemente, a do PAG. Sugere-se também que a avaliação da suplementação seja feita em Centros de Saúde que tenham facilidade para tal.

[Diagnosis of iron deficiency in childhood]

Com o objetivo de enfatizar a importância da escolha adequada de um parâmetro foi analisado o diagnóstico de deficiência de ferro de 855 crianças, com 60 meses e menos de idade, utilizando o padrão proposto pela OMS (11,0 g/dl) e outros. A inclusão de maior número de "falsos-positivos", resultante de parâmetros de maior sensibilidade do que o da OMS, é compensada pela garantia de tratamento à maior parte das crianças ferro-deficientes. Ao mesmo tempo que tal ampliação de programa é importante em sociedades de países em desenvolvimento, onde a prevalência de anemia é elevada, esta extensão é factível de ser executada dado o baixo custo do suplemento de ferro.

Implications of nutritional status on human biochemistry, physiology, and health

Optimum nutrition is the level of intake that should promote the highest level of health. Although excess caloric intake will lead to obesity, a deficit in nutrition may result in a tissue depletion of essential nutrients that can lead to biochemical changes and eventually to clinical signs and symptoms. Nutrition requirements may differ according to sex, age, activity, or physiological state and can be influenced by drugs, smoking, alcohol, and other factors. With ever-increasing sedentary life styles and less physically demanding jobs, the resulting reduced caloric requirements have made it more difficult to make nutritionally sound food choices. Nutrition is the single most important component of preventive health care. Diet has been associated with cancer, heart disease, diabetes, stroke and hypertension, arteriosclerosis, and cirrhosis of the liver. The ability of the human to respond to stresses, such as altitude, heat, trauma, surgery, and infection can be influenced by nutritional status. Nutritional status is reflected in a variety of metabolic processes that provide the basis for a number of methods for its assessment.

Hemoglobin levels in a Himalayan high altitude population

This report presents data on hemoglobin concentrations in a sample of Himalayan high altitude natives measured at their habitual altitude of residence. In this sample of 270 healthy Tibetan adults resident at 3250-3560 m in Upper Chumik , Nepal, the mean hemoglobin concentration is 16.1 +/- 1.2 gm/dl among adult males, 14.4 +/- 1.4 gm/dl among premenopausal and 15.0 +/- 1.1 gm/dl among postmenopausal adult females. 123 of 126 (98%) males, 96 of 100 (96%) premenopausal and 36 of 44 (82%) postmenopausal females have hemoglobin concentrations within two standard deviations of the sea level mean. These data demonstrate that a healthy population may reside at high altitude without the degree of elevation in hemoglobin widely known and cited for Andean highlanders. Comparing published data on mean hemoglobin concentrations of adult Himalayan and Andean samples residing between 3200 m and 4100 m reveals that Himalayan means are systematically lower. This in turn may account for the reported population differences in the prevalence of chronic mountain sickness ( Monge 's disease). It is hypothesized that Himalayan and Andean highlanders represent alternative patterns of high altitude hematological adaptation.

Proposal for the standardization of the serum unsaturated iron binding capacity assay, and results in groups of subjects with normal iron stores and with prelatent, latent, and manifest iron deficiency

An effort has been made to standardize the indirect iron saturation excess method for the determination of the serum unsaturated iron binding capacity (UIBC) and thus to relinquish the direct adsorption methods for the assay of the serum total iron binding capacity (TIBC) which give falsely high results due to unspecific binding of the saturating iron to serum proteins. In order to eliminate the interfering effects of hydrolytic polymerization of iron(III) on the saturation of apotransferrin in serum and on the colorimetric determination of the unbound iron excess at pH 8.3, conditions have been studied for the preparation of the iron-nitrilotriacetate-complex (Fe(NTA)2) solution at pH 8.3 with respect to its reactivity with the reductant sodium ascorbate and with the chromogen bathophenanthroline-disulfonate in photometric standards and in samples containing iron-saturated serum. The validity of the results for the UIBC thus obtained has been investigated (1) by direct spectrophotometric titration with Fe(NTA)2 of the apotransferrin in serum by measuring the absorbance of transferrin at 470 nm in 50-mm cuvettes, and of the UIBC using the modified indirect iron saturation excess assay, both of which gave the same saturation points, and (2) by the correlation of the TIBC obtained from serum iron determinations and the UIBC, with the transferrin concentration measured by the radial immunodiffusion assay. Results of UIBC determinations are presented along with serum iron concentration, TIBC, and transferrin saturation in groups of subjects with normal iron stores and prelatent, latent, and manifest iron deficiency.

Red cell indices in normal adults residing at altitude from sea level to 2670 meters

Hemoglobin (Hb), packed cell volume (PCV), red blood cells (RBCs), mean cell volume (MCV), and mean cell hemoglobin concentration (MCHC) were measured by a single operator in a single laboratory by means of an electronic particle counter in 942 healthy adults (491 females and 451 males) residing at five altitudes: 0, 1000, 1860, 2220, and 2670 meters above sea level. The subjects were carefully screened clinically, and subjects with low transferrin saturation (less than 15%) were excluded. In both sexes there was a differential behavior as a function of altitude, of Hb and PCV on the one hand, and number of RBCs on the other. The findings suggest the presence of two sequential mechanisms of adaptation to progressively lower atmosphere oxygen pressure: One operating from sea level to 1860 meters, which leads to a progressively increasing number of relatively microcytic RBC; and a second one -- from 1860 to 2670 meters -- in which there is an increased but constant number of progressively more normocytic RBC, so that a simplistic model of equal magnitude increases in the three parameters and is seen at 2670 meters, but not at the intermediate altitudes. The middle group's comparativity, essential to these interpretations, apparently was achieved with regard to time elapsed between sampling and testing and with regard to the people integrating the groups.

Nutritional needs of special populations at risk

The nutritional needs of special populations at risk require a concerned government, a concerned bureaucracy which funds and operates health, welfare and food delivery systems. Equally, if not even more important, is the concern and involvement of citizens at the "local-state-county-city" level. Some of the vulnerable groups, such as the migrant workers and the Native Americans, are the responsibiliity of the Federal Government. This does not mean that State and local citizens should do nothing, which by and large characterizes what has happened. The solution to provide optimum nutrition for the entire U.S. population is not merely a recitation of: food production figures, food costs, documentation of how much the Government spends on feeding people, how many free or reduced school lunches are served, how good or bad the problem is. We need to update and monitor programs that deal with the delivery of health, welfare and food; nutrition education for educators, Congress, doctors, and the public; food enrichment and fortification; nutrient analysis of foods; and nutrition research.

Changes in haemoglobin and haematocrit values in children aged 6 to 13 1/2 years in Mexico City

Levels of haemoglobin (Hb), haematocrit (Ht) and mean corpuscular haemoglobin concentration (MCHC) were determined in 523 boys and 350 girls, clinically healthy, ages 6-0 to 13-5 years, middle socio-economic class living in Mexico City. In girls no significant differences according to age were observed in Hb or MCHC; however, Ht was significantly greater at 10-5 than at 10-0 years, without subsequent modifications. In boys, Hb and Ht had a first increase between 10-5 and 11-0 years and a second rise from 12-5 years on: MCHC remained unchanged. Boys were six to twelve months behind girls in regard to Ht increase; however, Ht increased when boys and girls reached similar mean weights (34 kg), heights (138 cm) and surface areas (1-15 m2); concomitantly, they had progressed to stage 2 of sexual development. Clear sex differences began to appear at age 11-5 when boys had higher Hb and Ht values than girls. These data suggest that Hb and Ht changes in these children are not related to chronological age but can be better interpreted if compared to weight, height, surface area or stage of sexual development.

Developmental change in red blood cell volume: implication in screening infants and children for iron deficiency and thalassemia trait

The mean corpuscular volumen when determined by electronic counter is an accurate tool for identification of children with microcytosis due to either iron deficiency or thalassemia trait. The purpose of this report is to describe the normal developmental changes in MCV that occur in children afler 6 months of age. In 211 healthy infants and children screened to exclude those with borderline or overt iron deficiency, thalassemia trait, or hemoglobinopathy, we found that the lower limit of normal for MCV is 70 ft between 10 and 17 months of age and that there is a gradual increase of MCV with age; the lower limit is 74 between 1 1/2 and 4 years and 76 between 4 and 7 years. All of these values are well below the minimum adult level of 80 fl.

The incidence of anemia in residents of Missouri

A state-wide nutritional health survey of Missouri residents conducted in 1973 included hemoglobin, hematocrit, and serum iron determinations on approximately 1,164 persons and dietary iron intake estimates, based on a diet history, for 530 persons. Based on the criteria used for interpretation of the Ten-State Nutrition Survey data, over 19% of all preschool age white children and over 10% of the white children six to 10 years old had low or deficient hemoglobin levels. Between 8 and 17% of the white males between 10 and 60 years old and over 30% of the white males over 59 years old were anemic. Between 3 and 9% of all white females over 9 years of age had low or deficient hemoglobin levels. The levels of anemia for most age and sex groups of Negroes were at least twice as great as for corresponding groups of white persons. Low or deficient hemoglobin levels within the age and sex groups were associated with low hematocrit and serum iron levels; suggesting that some of the anemia was a reflection of iron deficiency. Estimates of the dietary intake of iron indicated that less that 20% of the females 10 to 35 years old and less than 60% of older females and boys under 17 years of age were consuming the Recommended Dietary Allowances. Over 35% of the preschool children and females between 10 and 60 years old were consuming less than two-thirds of their Recommended Dietary Allowances for iron. At least part of the iron deficiency was, therefore, indicated to be related to insufficient dietary intake.

Iron deficiency in an Eskimo village. The value of serum ferritin in assessing iron nutrition before and after a three-month period of iron supplementation

The serum ferritin concentration, a new means of assessing iron nutrition, was utilized in conjunction with the hematocrit value, serum iron concentration, and total iron binding capacity to determine the effect of a three-month period of iron supplementation in a group of 146 Eskimo children in Chevak, Alaska. Before treatment, 41% of the children had concentrations of serum ferritin below normal, 18% had a subnormal serum transferrin saturation, and 26% were anemic. After supplementation, only 6% had a subnormal serum ferritin concentration. Despite this evidence of improved iron stores in the group as a whole, the prevalence of low serum transferrin saturation and of anemia remained high, 15% and 17%, respectively. These results could be explained by a high incidence of infection, which, like iron deficiency, is associated with anemia and a low serum transferrin saturation. We conclude that the serum ferritin determination reflected an improvement in iron nutrition that was not as readily apparent by other measurements, and that factors other than iron deficiency also played an important role in the mild anemia that was prevalent in Chevak.

Screening for abnormal haemoglobins: a pilot study

A pilot study has been made of the implication of screening for abnormal haemoglobins in immigrant schoolchildren. An abnormality was detected by capillary blood haemoglobin electrophoresis in 8.4% of 6,835 children and a haemoglobinopathy outpatient clinic had to be established to deal with the heavy work load which resulted. The clinic was also used to determine the value of investigating the remaining members of the family once an abnormality had been detected in one child.Healthy siblings with normal haemoglobin electrophoretic patterns and normal iron and folate levels were studied to determine a normal range for haemoglobin in relation to age for adequately nourished immigrant children. The lower limit of the normal range was close to the mean value minus 1(1/2) S.D.; by using this definition 10.3% of 280 children were subsequently found to be anaemic.Population screening of this type is desirable, but further pilot studies of patient education, genetic counselling, organization of specimen collection, data processing, and follow-up health care facilities are required before screening is extended more widely in the United Kingdom.