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I J Griffin

Publications and source records attributed to I J Griffin.

At least 19 recordsLinked to original sources
PubMed2004

Current issues in nutritional management of very low birth weight infants.

Infants less than 1,500 g birth weight (very low birth weight, VLBW) are at risk for significant nutritional deficiencies. Enhancing nutritional care of these infants during their first months of life may have important short and long-term benefits. In this article we will consider several areas of recent research in the nutritional management of VLBW infants. In particular we will focus on issues related to the introduction and use of enteral nutrition. These issues include avoiding mineral deficiencies, early (minimal) enteral nutrition, human milk fortification, and postdischarge nutrition. Transitioning VLBW infants successfully to enteral nutrition is a key to their achieving adequate growth and development without the long-term risks related to parenteral nutrition. Human milk is a key component of any strategy for enteral nutrition of all infants. Its introduction in the first days of life leads to improved growth and better health outcomes for infants. However, although some nutrients are initially increased in the milk of mothers delivering prematurely, there are inadequate amounts of calcium, phosphorus, zinc and other nutrients to meet the needs of the VLBW infant during growth. Therefore, safe and effective means of fortifying human milk are essential to the care of VLBW infants. The optimal approaches for this fortification and the potential risks related to human milk fortification remain controversial. Limited data are available for the optimal content, initiation and methods for mixing fortifier with human milk.

Enteral Nutrition↗
PubMed2003

Zinc absorption by infants.

UNLABELLED: Zinc is a vital mineral in human nutrition and rare cases of overt zinc deficiency are well described in term and preterm infants. A variety of methods have been developed to assess zinc absorption, retention and balance in humans, either using mass (metabolic) balance or stable isotope-based METHODS: The different methods have different benefits and disadvantageous. Many studies have used such methods to examine zinc absorption in term and preterm infants. In preterm infants the main interest has been establishing whether different diets lead to positive zinc balance and approached in utero accretion rates. The earliest studies were concerning as they suggested that preterm infants may be in negative zinc balances for prolonged periods after birth. Subsequent studies have been more contradictory and it remains unclear from the literature how much zinc preterm infants absorb early in life. Nor is it clear whether poor zinc absorption during this period has any long-term consequences. Studies in term infants have suggested no such prolonged period of negative zinc balance. Generally the absorption values are in line with those used by the Institute of Medicine in the most recent edition of the Dietary Reference Intakes. Other studies have been designed to assess the effect of changes in formula composition on zinc intake (e.g. the presence or absence of lactose, high vs low zinc contents, etc.). Ho-wever, despite almost 20 studies of zinc absorption in infants many physiologically important questions remain unanswered, especially in preterm infants.

Breast Feeding↗
PubMed2002

Non-digestible oligosaccharides and calcium absorption in girls with adequate calcium intakes.

Non-digestible oligosaccharides such as inulin and oligofructose have been shown to consistently increase calcium absorption in experimental animals, but data in humans are less clear-cut. The objective of this study was to assess the effect of 8 g/d of oligofructose or a mixture of inulin and oligofructose on calcium absorption in girls at or near menarche. A total of fifty-nine subjects were studied using a balanced, randomized, cross-over design. They received, in random order, 8 g/d placebo (sucrose), oligofructose or the mixture inulin+oligofructose for 3 weeks, separated by a 2-week washout period. Throughout the study, subjects consumed a total of approximately 1500 mg/d dietary calcium, by adding two glasses of calcium-fortified orange juice to their diet. Four grams of placebo, oligofructose or the mixture inulin+oligofructose was added to each glass of orange juice immediately before it was consumed. At the end of each 3-week adaptation period, calcium absorption was measured, using a dual stable isotope technique, from the cumulative fractional excretion of an oral and an intravenous tracer over 48 hours. Calcium absorption was significantly higher in the group receiving the inulin+oligofructose mixture than in the placebo group v. P=0.01), but no significant difference was seen between the oligofructose group and the placebo group v. P=NS). We conclude that modest intakes of an inulin+oligofructose mixture increases calcium absorption in girls at or near menarche.

Adolescent↗
PubMed2002

Zinc protoporphyrin/haem ratio and plasma ferritin in preterm infants.

OBJECTIVE: To study the utility of the zinc protoporphyrin/haem (ZPP/H) ratio as a measure of iron status in healthy, growing, preterm infants. METHOD: ZPP/H was measured in 109 well, preterm infants from the time of hospital discharge until 1 year of age (637 determinations). RESULTS: ZPP/H was initially high, but steadily declined. This was opposite to what was expected from the known changes in iron stores during the first year of life and the observed changes in plasma ferritin. Subjects with higher ZPP/H ratios tended to have lower ferritins, but changes in ZPP/H in a given subject were poorly reflected by changes in plasma ferritin. Between 6 and 9 months of age, ZPP/H correlated with other measures of iron status, but serum ferritin concentration did not. CONCLUSION: Use of the ZPP/H ratio as a measure of iron status during the first year of life appears to be confounded by the developmental changes in ZPP/H, but in the later half of this period it may be a better measure of iron status than serum ferritin.

Female↗
PubMed2002

Using stable isotopes to assess the bioavailability of minerals in food fortification programs.

The fortification of various types of food with minerals is often undertaken without consideration of either their bioavailability or the potential nutrient-nutrient interactions resulting from their use. Stable isotopes provide a safe and accessible method of resolving these issues by providing the proper evidence in each case. They must be conducted according to strict safety and ethical guidelines and may be readily conducted in a field setting. Clinical studies in children enable researchers, policymakers, and food manufacturers to obtain the data necessary to determine the best way to fortify specific foods and beverages, in order to optimally enhance the nutritional health of growing children. We have shown the utility of this approach in studies in both developing countries and in the United States.

Biological Availability↗
PubMed2001

Iron and breastfeeding.

Given the importance of iron nutrition during the first year of life, there are surprisingly few true, randomized, controlled studies addressing this issue; however, it seems that iron deficiency is unlikely in full-term, breastfed infants during the first 6 months of life because these infants' body iron stores are sufficient to meet requirements. After this time, many infants exhaust their iron stores and become dependent on a secondary dietary iron supply. Although iron deficiency is a significant nutritional problem worldwide, most of the adverse effects of iron deficiency in this age group are hypothetical and rely on extrapolation from animal studies or studies at different ages. This, however, also is true of most of the adverse effects of iron excess in this age group. Given this uncertainty, it seems prudent to use the lowest dose of iron that prevents iron-deficiency anemia. Currently, the best evidence is that this is achieved by prolonged breastfeeding, avoidance of unfortified formulas and cow's milk, and the introduction of iron-fortified and vitamin C-fortified weaning foods at approximately 6 months of age. Despite much research, there are many areas of uncertainty regarding iron supplementation of infants, including that: 1. The optimal age for introducing iron-fortified supplemental foods is poorly defined and should be further evaluated. 2. The natural history of iron deficiency and iron-deficiency anemia during the first year of life is unclear, as are the possible long-term effects of this, especially on developmental outcome. 3. The biologic variability among infants and among their mothers that allows many infants who do not receive iron-fortified foods to prevent iron deficiency while receiving only human milk throughout the first year of life is intriguing and warrants additional study. 4. The iron requirements of small-for-gestational-age, term infants are unknown. Their iron requirements are likely to be higher than those of average term infants, but whether iron supplements are required is unclear. 5. The optimum amount of dietary iron in the weaning diet needs to be further defined. Similarly, the optimal source and amount of iron in infant formulas given to infants who receive a mixture of human milk and formula is unclear.

Age Factors↗
PubMed2001

Calcium fortification of breakfast cereal enhances calcium absorption in children without affecting iron absorption.

OBJECTIVES: Provision of calcium-fortified foods may represent an important component of improving the calcium intake of children. We sought to determine whether the addition of calcium to cereal would have a net positive effect on calcium absorption without decreasing iron absorption. METHODS: Twenty-seven children, 6 to 9 years of age, were provided two servings per day (30 g of cereal per serving) of either a low (39 mg/serving) or fortified (156 mg/serving) calcium-containing cereal product for 14 days. Calcium absorption was measured by using stable isotopes added to milk (extrinsically labeled) and to the calcium-fortified cereal (intrinsically labeled). RESULTS: Fractional calcium absorption from the fortified cereal was virtually identical to that from milk. Fractional absorption of calcium from milk did not differ significantly when given with enriched or low-calcium-containing cereal. Total calcium absorption increased from 215 +/- 45 mg/d to 269 +/- 45 mg/d with the addition of the calcium-fortified cereal (P <.001). Iron absorption was similar when children received the calcium-fortified cereal or unfortified cereal. CONCLUSIONS: The addition of a moderate amount of calcium to a cereal product was beneficial to calcium absorption and did not interfere with iron absorption. Use of calcium-fortified food products may be considered a practical approach to increasing the calcium intake of children.

Absorption↗
PubMed2001

Feeding preterm infants after hospital discharge: growth and development at 18 months of age.

We have shown that preterm infants fed a preterm formula grow better than those fed a standard term infant formula after hospital discharge. The purpose of this follow-up study was to determine whether improved early growth was associated with later growth and development. Preterm infants (< or =1750 g birth weight, < or =34 wk gestation) were randomized to be fed either a preterm infant formula (discharge to 6 mo corrected age), or a term formula (discharge to 6 mo), or the preterm (discharge to term) and the term formula (term to 6 mo). Anthropometry was performed at 12 wk and 6, 12, and 18 mo. Mental and psychomotor development were assessed using the Bayley Scales of Infant Development II at 18 mo. Differences in growth observed at 12 wk were maintained at 18 mo. At 18 mo, boys fed the preterm formula were 1.0 kg heavier, 2 cm longer, and had a 1.0 cm greater occipitofrontal circumference than boys fed the term formula. Boys fed the preterm formula were also 600 g heavier and 2 cm longer than girls fed the preterm formula. However, no differences were noted in MDI or PDI between boys fed the preterm formula and boys fed the term formula or between the boys fed preterm formula and girls fed the preterm formula. Overall, boys had significantly lower MDI than girls (mean difference, 6.0; p < 0.01), primarily reflecting lower scores in boys fed the term formula. Thus, early diet has long-term effects on growth but not development at 18 mo of age. Sex remains an important confounding variable when assessing growth and developmental outcome in these high-risk infants.

Child Development↗
PubMed2000

Body weight-specific zinc compartmental masses in girls significantly exceed those reported in adults: a stable isotope study using a kinetic model.

Maintaining optimal zinc status is important for normal growth and development in children, but minimal data are available regarding zinc metabolism in this age group. Our objectives were to utilize stable isotope-based compartmental modeling techniques to investigate zinc metabolism in healthy children; to expand a current stable isotope-based model to include red blood cell data; and to compare kinetic parameters in children with those previously reported in adults. Seven healthy girls, age 9.94 +/- 0.79 y, received 1.1 mg of a (67)zinc-enriched tracer orally and 0.5 mg of a (70)zinc-enriched tracer intravenously. Blood, urine and fecal samples were collected for 6 d. Stable isotope enrichments were measured by thermal ionization magnetic sector mass spectrometry. A six-compartment model based on a model previously reported in adults was used; the model excluded red blood cell data. Body weight-corrected masses of the body zinc compartments derived using this model were significantly greater in children than those reported in adults. Modification of the model to include a red blood cell compartment increased the total identifiable zinc mass of the nongastrointestinal compartments by approximately 2.5%. We conclude that compartmental modeling can be used to describe zinc kinetics in children, and that the body weight-corrected zinc pool masses are significantly greater in children than in adults.

Adult↗
PubMed1999

Body composition of preterm infants during infancy.

AIMS: To examine body composition in preterm infants. METHODS: Body composition was measured by dual energy x-ray absorptiometry (DEXA) at hospital discharge, term, 12 weeks, and at 6 and 12 months corrected age in 125 infants (birthweight < or = 1750 g, gestational age < or = 34 weeks). RESULTS: Body weight derived by DEXA accurately predicted that determined by conventional scales. In both sexes lean mass (LM), fat mass (FM), %FM, bone area (BA), bone mineral mass (BMM), and bone mineral density (BMD) increased rapidly during the study; significant changes were detectable between discharge and term. At 12 months, LM, BA, and BMM, but not FM, %FM, or BMD were greater in boys than in girls. Corrected for age, LM was less than those of the reference term infant; FM and %FM were similar; BMM was greater. Corrected for weight, LM was similar to those of the reference infant, while the FM and %FM of study infants were slightly greater. CONCLUSIONS: DEXA accurately measures body mass. Body composition in preterm boys and girls differs. Interpretation of DEXA values may depend on whether age or body weight are regarded as the appropriate reference.

Absorptiometry, Photon↗
PubMed1999

Iron nutritional status in preterm infants fed formulas fortified with iron.

AIMS: To prospectively evaluate the iron nutritional status of preterm infants fed either a term (0.5 mg/dl iron) or preterm (0.9 mg/dl) formulas fortified with iron after hospital discharge. METHODS: Healthy low birthweight preterm infants were randomly assigned into three groups at the time of hospital discharge. Group A were fed an iron fortified preterm formula (0.9 mg/dl iron) until 6 months corrected age; group B, a fortified term formula (0.5 mg/l iron) until 6 months corrected age group C, the preterm formula between hospital discharge and term, then the term formula until 6 months corrected age. RESULTS: Seventy eight infants were followed up to 6 months corrected age. Iron intake from formula differed significantly between the groups (A, 1.17 mg/kg/day (SD 0.32) > C, 0. 86 mg/kg/day (SD 0.40) = B, 0.81 mg/kg/day (SD 0.23); p < 0.0001). Haemoglobin concentrations were similar to those of iron sufficient preterm infants of the same postnatal age, and term infants of the same postmenstrual age (after 3 months of age). There were no significant differences in haemoglobin concentration (p = 0.391), plasma ferritin (A vs B, p = 0.322), or in the incidence of iron deficiency (A vs B, p = 0.534). CONCLUSIONS: Iron fortified formulas containing between 0.5 and 0.9 mg/dl iron seem to meet the iron nutritional needs of preterm infants after hospital discharge.

Analysis of Variance↗
PubMed1999

Knee-heel length measurement in healthy preterm infants.

AIM: To examine the reproducibility of crown-heel length measurement; the precision and reproducibility of knee-heel length measurement; and the association between the two in healthy preterm infants. METHODS: Paired crown-heel and knee-heel lengths were measured on 172 occasions by three observers in 43 preterm infants between 205 and 458 days of postconceptional age. RESULTS: Crown-heel length (CHL) measurement was highly reproducible, with a coefficient of variation (CV) of 0.41%. Knee-heel length (KHL) measurement was relatively precise (CV 0.78%), but less reproducible (intra-observer CV 1.77%, intra-observer CV 2.11%), especially in larger infants. The association between KHL and CHL was not consistent and varied with age. KHL was a poor predictor of CHL, with a 95% predictive interval of +/- 27.5 mm. CONCLUSIONS: KHL was less reproducible than CHL, especially in larger infants, and a poor predictor of CHL.

Humans↗
PubMed1999

Feeding preterm infants after hospital discharge: effect of diet on body composition.

Our purpose in this study was to examine whole body composition, using dual energy x-ray absorptiometry (DEXA) during dietary intervention in preterm infants (< or = 1750 g birthweight, < or = 34 wk gestation). At discharge, infants were randomized to be fed either a preterm infant formula (discharge-6 mo; group A) or a term formula (discharge-6 mo; group B), or the preterm formula (discharge-term) and the term formula (term-6 mo; group C). Nutrient intake was measured between each clinic visit. To measure body composition, DEXA was used at discharge, term, 12 wk, 6 mo, and 12 mo corrected age. The data were analyzed by ANOVA. At discharge, no differences were noted in patient characteristics between groups A, B, and C. Although energy intakes were similar, protein and mineral intakes differed between groups (A > C > B; p < 0.0001). During the study, weight gain and LM gain were greater in group A than B. At 12 mo, weight, LM, FM, and BMM but not % FM or BMD were greater in group A than B. However, the effects of diet were confined to boys, with no lasting effects seen in girls. In summary, therefore, DEXA was precise enough to detect differences in whole body composition during dietary intervention. Increased weight gain primarily reflected an increase in LM and is consistent with the idea that the preterm formula more closely met protein and/or protein-energy needs in rapidly growing preterm male infants.

Absorptiometry, Photon↗
PubMed1998

Feeding preterm infants after hospital discharge: effect of dietary manipulation on nutrient intake and growth.

The objective of this study was to compare formula intake, the time of weaning, and growth in preterm infants (< or = 1750-g birth weight, < or = 34-wk gestation) fed a standard term or preterm infant formula after initial hospital discharge. Infants were randomized at hospital discharge to be fed a preterm infant formula from discharge to 6 mo corrected age (group A), a term formula from discharge to 6 mo (group B), or the preterm formula (discharge to term) and the term formula (term to 6 mo (group C). Infants were seen biweekly (discharge to term) and monthly (term to 6 mo), when intake was measured and anthropometry and blood sampling were performed. The results were analyzed using ANOVA. Although nutrient intake was similar, at 6 mo girls were lighter (6829 versus 7280 g) and shorter (64.4 versus 66.0 cm) than boys (p < 0.05). Patient characteristics were similar between the treatment groups. Although the volume of intake differed (B > C > A; p < 0.001), energy intake was similar in the groups. Because of differences in formula composition, protein, calcium, and phosphorus intakes differed (B < C < A; p < 0.001). Lower protein intakes were related to lower blood urea nitrogen levels (B < C < A; p < 0.001). At 6 mo, infant boys in B and C were lighter (6933, 6660 < 7949 g), shorter (65.3, 64.9 < 67.1 cm), and had a smaller head circumference (43.7, 43.7 < 44.8 cm; p < 0.05) than infants in group A. Preterm infants were found to increase their volume of intake to compensate for differences in energy density between formulas. After hospital discharge, infant boys fed a preterm formula grew faster than infant girls fed a preterm formula or infant boys fed a term formula.

Blood Urea Nitrogen↗
PubMed1995

Pelvic ultrasound measurements in normal girls.

Pelvic ultrasound scans were carried out in 153 normal girls aged between 3 days and 14.9 years, in order to obtain reference data for ovarian volume, uterine length and uterine configuration. The right ovary was significantly larger than the left (by about 17%). Ovarian volume increased exponentially with age, over this age range. No relationship with pubertal stage (independent of age) could be demonstrated. Uterine length decreased from birth to 4 years, before steadily increasing. The fundal-cervical ratio (FCR) decreased initially then increased to lie above 1.0 by 15 years of age. A midline endometrial echo was seen in half of the subjects aged less than 6 months, but otherwise it was not seen before 11.8 years of age or at Tanner stage B2. Smoothed reference centile curves for uterine length, right and left ovarian volume were produced, allowing z scores (or SD scores) to be calculated for each measurement.

Adolescent↗
PubMed1995

Pelvic ultrasound findings in different forms of sexual precocity.

Recently produced reference curves for various ultrasound dimensions were used to retrospectively assess 67 pelvic ultrasound scans carried out at the initial presentation in girls with sexual precocity. At presentation the group with precocious puberty had significantly increased uterine lengths and ovarian volumes compared with the normal population, and a significantly increased fundal-cervical ratio. Ovarian volume was also significantly increased in therlarche and thelarche variant. The fundal-cervical ratio was significantly increased in thelarche variant. There was considerable overlap between individuals with sexual precocity and normal subjects. The ultrasound findings that best discriminated early or precocious puberty from other forms of sexual precocity were the presence of a midline endometrial echo, and a uterine length above the 97th centile for age. An entirely normal pelvic ultrasound at presentation did not rule out the possibility of precocious puberty.

Child↗