A Comparison of the Zinc, Copper and Manganese Status of Very Low Birth Weight Pre-Term and Full-Term Infants during the First Twelve Months

During a longitudinal study, hair samples and dietary intake data were collected from 50 preterm (mean birth weight = 1054 ± 234 g, mean gestational age = 29 ± 2.5 weeks) and 60 full-term infants (mean birth weight = 3 509 ± 269 g, mean gestational age = 40+1 weeks) at 3, 6 and 12 months of age. Mean daily zinc, copper and manganese intakes were calculated using three-day dietary records and test-weight data for the breast-fed infants. Hair samples were analyzed for these elements by instrumental neutron activation analyses. The medium hair zinc concentration in the pre-term group at six months (81 μg/g) was lower ( p < 0.05) than that of the full-term group (144 μg/g) and was associated with lower mean dietary zinc intakes at 3 and 6 months. At 12 months, the median hair copper (12.5 μg/g) and manganese (0.18 μg/g) concentrations for the pre-term were lower ( p < 0.05) than those of the full-term infants (Cu = 16.5 μg/g; Mn = 0.25 μg/g) and were also associated with low dietary copper and manganese intakes     

Total energy expenditure, body composition and weight gain in moderately preterm and full-term infants at term postconceptional age

AIM: To assess total energy expenditure (TEE) and body composition, i.e. total body water (TBW) and adipose tissue volume (ATV), at term age in 8 healthy preterm infants, born between gestational weeks 30 and 33, and in 9 healthy full-term newborns. METHODS: Total and subcutaneous ATVs were assessed using magnetic resonance imaging, while TEE and TBW were estimated using doubly labelled water. RESULTS: Total ATV was 272 +/- 21 and 261 +/- 56 ml/kg body weight, while subcutaneous ATV was 88.9 +/- 1.6 and 89.7 +/- 2.0% of total ATV for preterm and full-term infants, respectively. The corresponding figures for TBW (as percentage of body weight) were 67.4 +/- 2.5 and 68.1 +/- 4.1, respectively. A significant correlation between ATV/kg body weight and body weight was found for full-term (p < 0.0001) but not for preterm infants. TEE for preterm infants was 315 +/- 20 kJ/kg body weight/24 h, which was significantly higher (p < 0.05) than TEE for full-term infants (254 +/- 45 kJ/kg body weight/24 h). At the time of investigation preterm infants weighed significantly (p < 0.05) less (540 g) than full-term infants. After the time of investigation, weight gains of preterm and full-term infants were 38 +/- 12 and 24 +/- 14 g/24 h, respectively. CONCLUSION: When compared to full-term newborns, predominantly breastfed healthy preterm infants at term postconceptional age were significantly smaller, had a similar average proportion of body fat and showed catch-up growth. Their higher TEE/kg body weight can be explained by a higher growth rate and possibly also by higher physical activity.     

Fetal growth and the timing of exposure to maternal smoking

BACKGROUND: Maternal smoking during the third trimester reduces the birthweight of the full-term neonate. We assessed the relationship between the timing of exposure to maternal smoking, gestational period, weight and body length for both full-term and preterm neonates. METHODS: A retrospective study with a questionnaire was conducted in 1194 infants who participated in the official medical examination for 3-year-old infants. RESULTS: The risk of preterm birth from mothers who smoked during any trimesters was significantly increased. The body length of neonates whose mothers smoked during the third trimester was shorter than that of neonates whose mothers did not smoke during the third trimester. The weight of full-term neonates whose mothers smoked during the third trimester was lighter than that of neonates whose mothers did not smoke during the third trimester. CONCLUSIONS: Maternal smoking during any trimesters increased the risk of preterm birth. Maternal smoking during the third trimester reduced the body length of both full-term and preterm neonates, and the birthweight of the full-term neonate in a somewhat dose-dependent manner.     

Trace elements in meconium from preterm and full-term infants

Meconium samples from 23 preterm infants (birth weight = 1,097 +/- 359 g; gestational age 29 +/- 3 weeks, mean +/- SD) and 27 full-term infants (3,453 +/- 476 g; 39.5 +/- 1 weeks) were analyzed for zinc, copper, manganese, chromium and iron by atomic absorption spectrometry. Compared to meconium from preterm infants, full-term infants had an elevated (p less than 0.05) total excretion (microgram) of zinc (957 +/- 545 vs. 503 +/- 506), copper (245 +/- 256 vs. 128 +/- 94) and manganese (62 +/- 55 vs. 29 +/- 29), but not iron (190 +/- 147 vs. 332 +/- 532) or chromium (0.4 +/- 0.19 vs. 0.75 +/- 1.0). Two preterm infants had high losses (1.5 and 2 mg) of iron in their meconium. Zinc, copper and manganese losses into meconium appear to increase with gestation, whereas iron and chromium losses occur early in gestation and may be reabsorbed by term.     

Randomized controlled study of the effects of different durations of light exposure on weight gain by preterm infants in a neonatal intensive care unit

A randomized controlled study was carried out on 96 preterm infants (< 37 wk) with birthweight less than 2000 g admitted to a neonatal intensive care unit. The aim was to compare the weight gain between preterm infants exposed to 12 h cyclical lighting (intensity of light: 78.4 +/- 24.7 lux, mean +/- SD) and those exposed to a continuously dim environment (5.9 +/- 1.9 lux). The exclusion criteria were infants with major congenital malformations or who needed continuous lighting for treatment procedure and care. From day 7 of life until discharge, 50 infants were randomized to receive 12 h cyclical lighting and 46 infants to a continuously dim environment. There was no significant difference in the mean birthweight (12 h lighting vs continuously dim: 1482 vs 1465 g, p = 0.8), mean gestational age (31.6 vs 31.4 wk, p = 0.6), median duration of hospital stay (28.5 vs 28.5 d, p = 0.8), mean age to regain birthweight (13.0 vs 12.9 d, p = 0.3), mean weight gained by day 14 (27.6 vs 36.2 g, p = 1.0), median weight gain per day (11.9 vs 12.2 g, p = 0.9) or median body weight on discharge (1800 vs 1800 g, p = 0.4) between the two groups of infants. CONCLUSION: Exposing preterm infants to either 12 h cyglical lighting or continuously dim environment did not have any significant effect on their weight gain during the neonatal period.     

Postnatal dependence of plasma copper and zinc levels on gestational age and maturity observed in infants fed a high zinc content formula

We studied the effect of gestational age and maturity on plasma zinc and copper levels at 10 and 120 days of age. The association of plasma zinc changes and body growth was also investigated. Infants were receiving a controlled intake of zinc and copper solely through a zinc-supplemented formula (4.7 mg/L of zinc and 0.16 mg/L of copper). Twenty-eight low-birthweight infants (less than 2,500 g) having gestational ages ranging from 33 to 40 weeks [17 with an appropriate birthweight for gestational age (AGA) and 11 small for gestational age (SGA)] were enrolled in the present study. Measurements of plasma zinc and copper concentration, weight, length, head circumference, and tricipital and subscapular skinfolds were carried out at 10 and 120 days of age. Proton-induced x-ray fluorescence technique (PIXE) was used to assess copper and zinc concentrations. At 10 days of age a significant correlation between copper concentration and gestational age was found. At 120 days of age the copper concentration was higher than at 10 days and independent of gestational age and maturity (mean +/- SEM = 116 +/- 5 micrograms/dl). At 10 days of age no significant correlation between zinc content and gestational age was found (86 +/- 4 micrograms/dl). The plasma zinc percent change over the period from 10 to 120 days of age was positively correlated with gestational age in the whole sample as well as in AGA and SGA infants separately.(ABSTRACT TRUNCATED AT 250 WORDS)     

Bilirubin-IXalpha and -IXbeta pigments, coproporphyrins and bile acids in meconium and stools from full-term and preterm neonates during the first month of life

Individual bilirubin pigments in the excreta were quantitated by newly developed methods. In meconium, bilirubin-IXbeta predominated, whereas bilirubin-IXgamma and -IXdelta remained undetectable. The daily excretion of bilirubin-IXalpha plus -IXbeta was 0.03-1.00 and 0.04-2.00 micromoles kg(-1) of birthweight in preterm and full-term infants, respectively. The ratio of bilirubin-IXalpha to -IXbeta in meconium was 0.25 +/- 0.34, 0.32 +/- 0.30 and 0.46 +/- 0.55 in newborns of gestational ages below 30, from 31 to 36 and above 36 wk, respectively. The predominance of bilirubin-IXbeta disappeared within the first week in those with gestational age >31 wk but more slowly in the very preterm group. The ratio of monoconjugated to diconjugated bilirubin-IXalpha was 4 to 5 in full-term infants, whereas this ratio was only reached after 1 mo in preterm infants. The ratio of glucuronide or glucoside to xyloside varied widely, independent of gestational age. No correlation between faecal UCB-IXalpha and beta-glucuronidase was observed. The daily coproporphyrin excretion fell from a median of 500 microg on day 1 to below 20 microg from day 7 onwards; this decrease correlated with that of bilirubin-IXbeta. The daily 3alpha-hydroxylated bile acid loss in the excreta was two- to fivefold higher than in the adult; this, together with the higher neonatal serum levels (12-90 nmoles ml(-1)), indicates an immature intestinal reabsorption and an enhanced bile acid synthesis. CONCLUSION: Both zinc coproporphyrin and bilirubin-lXbeta are characteristic compounds of human meconium, diconjugated bilirubin-IXalpha is low or absent in meconium of very preterm infants, and faecal and serum bile acids are high.     

Postnatal weight gain and serum total protein and albumin levels in very low birthweight (less than or equal to 1500 g) preterm infants

Postnatal weight gain during the first 8 weeks of life of 20 very low birthweight preterm infants (gestational age: 28.9 +/- 1.7 weeks, birthweight: 1098 +/- 199 g, mean +/- SD) was compared to the in utero weight gain of theoretical control fetuses. By the end of the study period preterm infants gained significantly less weight than their controls (155 +/- 15 vs 221 +/- 16%, p less than 0.001). During the first 6 weeks of life daily additional weight gain of the preterm infants was less than that of the controls, but after that time no significant difference was seen (7th-8th week: 12.0 +/- 3.6 vs 13.7 +/- 3.9 g/kg/day, study infants vs controls, ns). During the 7th-8th weeks of life positive correlation was found between calorie intake and weight gain (r = 0.33, F = 2.17, p less than 0.05). The changes in serum total protein and albumin levels, including an initial increase by the age of 2 weeks, were statistically not significant.     

Early postnatal growth evaluation in full-term,preterm and small-for-dates infants

Postnatal growth patterns of weight, length/height and head circumference in full-term (FTI), preterm (PTI) and small-for-dates (SFDI) infants, are described by using distance and velocity data together with the concept of growth per unit of body weight. The study was performed in 112 healthy Caucasian infants, of a similar socioeconomic status, in Montevideo, Uruguay.Median growth velocity (MGV) and median growth velocity per unit (MGVU) of body size are defined. The authors stress that: (a) growth velocity is related to body mass, (b) a useful evaluation of growth is made by using two consecutive measures with a certain time interval independently of birthweight and gestational age, and (c) expressing growth per day per unit relates well to daily nutritional and other requirements.     

Skinfold thickness and adiposity index in premature infants

In order to assess the validity of the weight per square of length ratio as an index of adiposity during the neonatal period, 37 premature infants (gestational age, mean +/- SD, = 31.5 +/- 1.1 weeks, birthweight, mean +/- SD, = 1.448 +/- 147 g) were studied for weight, length and skinfold thickness at 5 sites (biceps, triceps, subscapular, suprailiac and quadriceps) during their stay in the Neonatal Unit of the University Hospital in Lausanne. The results show a significant correlation between the adiposity index and the sum of 5 skinfold thickness sites in premature infants. The adiposity index gives a fair estimate of the body fat mass during the postnatal growth in premature infants.     

Early postnatal growth in preterm infants

Changes in weight of 50 preterm infants (gestational age 32.7 +/- 0.3 weeks, birthweight 1772 +/- 49 g) were studied during the period of the 0-4 postnatal weeks. Intrauterine weight gain of fetuses with equivalent gestational age, weight percentile position and sex was calculated and used as a control. Study infants achieved significantly less weight by age of 4 weeks (116.2 +/- 1.2%) than it could have been expected theoretically (144.7 +/- 1.0%). Growth performance did not correlate significantly with calorie intake, but was closely related with gestational age.     

Longitudinal follow-up of height up to five years of age in infants born preterm small for gestational age; comparison to full-term small for gestational age infants

OBJECTIVE: This aims to conduct a comparative study of the height catch-up rate in preterm small for gestational age (SGA) infants during early childhood by gestational age and identify the factors affecting short stature in comparison to full-term SGA infants. METHODS: 449 SGA infants (214 full-term infants, 73 infants with gestation of less than 32 weeks, and 162 infants with gestation of more than 32 weeks but less than 37 weeks) from 25 institutions in Japan were assessed for catch-up (> or = -2SD) rate in growth by measuring for length/height at 1 year, 3 years and 5 years of age and the risk factors for no catch-up (< -2SD) at 5 years. RESULTS: The overall length/height catch-up rate was 68% at 1 year, 89% at 3 years and 88% at 5 years. The catch-up rate at 3 and 5 years of age in the group with gestation of less than 32 weeks had a rate of 74%, which was significantly less than the other two groups (approximately 90%). A significant factor associated with short stature at 5 years in the group with gestation of less than 32 weeks was the lower length SD score at time of birth, and for preterm infants born more than 32 weeks of gestation and full-term infants, significant factors were the lower maternal height and head circumference at birth. CONCLUSION: SGA infants born less than 32 weeks of gestation had a higher risk of no catch-up and different factors affecting catch-up compared to preterm SGA infants of gestation more than 32 weeks and full-term SGA infants.     

Urinary excretion of prostaglandin E and F 2 alpha in healthy newborn infants and in infants with hyaline membrane disease

Urinary PGE and PGF 2 alpha excretion was estimated in 11 healthy full-term (mean birth weight, 3327 g; mean gestational age, 39.2 weeks). 15 healthy preterm (mean birth weight, 1722 g; mean gestational age, 32.1 weeks) and in 9 preterm infants suffering from hyaline membrane disease (HMD) (mean birth weight: 1454 g, mean gestational age: 31 weeks). Measurements were carried out on the 1st, 3rd and 5th days of life by radioimmunoassay, using Clinical Assays Inc. RIA kits. Urinary PGE excretion on the first day of life was 3.76 +/- 0.41 ng/day, 2.43 +/- 0.65 ng/day and 1.19 +/- 0.27 ng/day for healthy full-term, healthy premature and premature infants with HMD, respectively. The differences were significant at the level of p less than 0.05. With advancing postnatal age urinary PGE excretion markedly increased in each group (p less than 0.05). Urinary PGF 2 alpha excretion on the first day was 10.8 +/- 2.0 ng/day in full-term, 6.6 +/- 2.2 ng/day in healthy premature and 4.35 +/- 1.9 ng/day in premature infants with HMD. Then an inconsistent rise could be observed without statistically significant difference between the individual groups of various postnatal age and between the different groups of the same postnatal age. The decreased renal PGE production is suggested to be involved in the pathomechanism of HMD.     

Growth and catch-up growth of Australian infants of low birthweight

The growth of 90 infants of low birthweight (1500-2499 g) has been studied longitudinally from birth to 2 years of age. Seventy-five per cent of those infants were of birthweight that was appropriate-for-gestational age (AGA) and of mean gestational age 33.6 weeks (boys) and 34.5 weeks (girls). Twenty-four per cent were small-for-gestational age (SGA) and of mean gestational age 39.4 weeks (boys) and 38.5 weeks (girls). The data showed that, when gestational age was considered, the growth of AGA infants was similar to that of full-term infants of normal birthweight; SGA infants displayed accelerated growth ('catch-up'), particularly in the first months of life with upward percentile crossing from below the 5th toward the 50th. These results provide further evidence of the need to consider gestational age and whether AGA or SGA when assessing the growth of low birthweight infants.     

Poor weight gain of the low birthweight infant fed nasojejunally.

Forty-four appropriately grown preterm infants of birthweight 1-1.5 kg were allocated to nasojejunal (NJ) or nasogastric (NG) feeding at birth. Infants in the NJ group were transferred to NG feeding as soon as they weighed 1.5 kg. The mean caloric intake of infants in both groups was the same, but mean incremental weight velocity during NJ feeding was significantly less than during NG feeding. At expected date of delivery mean body weight and mean occipitofrontal circumference were significantly smaller in the NJ group. During the 3 months after the expected date of delivery, when all infants were being fed orally, the infants in the NJ group had significantly greater mean weight velocity and mean occipitofrontal circumference velocity than infants in the NG group so that by 3 months after the expected date of delivery there was no significant difference in bodyweight or occipitofrontal circumference between the groups. Low birthweight infants fed by the nasojejunal route from birth should be transferred to nasogastric feeding as soon as possible.     

Growth patterns in preterm infants born appropriate for gestational age

Aim:   This study aimed to document the growth patterns of a contemporary cohort of preterm infants born appropriate for gestational age (AGA). It was hypothesised that preterm AGA (PT-AGA) infants would display poorer growth than full-term AGA (FT-AGA) infants.
Methods:   Sixty-four PT-AGA infants and 64 FT-AGA infants were assessed at 0, 4, 8 and 12 months of corrected age (CA). Measurements of weight and length were recorded at each of the specified ages. Centers for Disease Control and Prevention growth data were used to calculate Z-scores for weight and length based on CA.
Results:   The mean length and weight Z-scores of PT-AGA infants were found to be significantly less than those of FT-AGA infants at term, 4, 8 and 12 months of CA ( P  < 0.001). The mean weight Z-score of PT-AGA infants was found to be less than their mean length Z-score at each time point, though the differences were not significant.
Conclusions:   The results of this study suggest that PT-AGA infants are likely to display poorer growth than FT-AGA infants until at least 1 year of CA. Long-term growth monitoring in this population is recommended.     

A COMPARATIVE STUDY OF VARYING PROTEIN INTAKE IN LOW BIRTHWEIGHT INFANT FEEDING

Svenningsen, N.W., Lindroth, M. and Lindquist, B. (Department of Paediatrics, University of Lund, Sweden). A comparative study of varying protein intake in low birthweight infant feeding. Acta Paediatr Scand. Suppl. 296: 28, 1982. — In a prospective longitudinal study of 48 very low birthweight and preterm infants with mean birthweight 1 385±343 and gestational age 30.8±2.9 w an assessment was made of the impact of varying the protein intake in the postnatal period from the 3rd to 7th week of life. The infants were randomly allocated to one of three dietary groups with isocaloric energy supply but different protein content—i.e. human milk (1.6 g/100 kcal), formula 1 (2.3 g/100 kcal) and formula 2 (3.0 g/100 kcal). In the human milk group 12 of 18 infants were fed their own mother's breastmilk. During the study period the mean weight gain was slightly higher in the infants fed formula 1 and 2. There were no group differences in S-albumin whereas B-urea-N and B-base deficit were significantly increased in the formula fed infants in comparison to infants fed human milk. After the study period until around 15 weeks of age the slope in weight gain remained slightly higher for formula fed infants. However, the gain in body length and head circumference was equal in all three groups. After around 8 months of age there was no difference in any growth parameter. Neurodevelopmental examinations showed no group differences during the follow-up period to 2 years of age.     

Meeting zinc and copper intake requirements in the parenterally fed preterm and full-term infant

To determine the intravenous zinc and copper intakes required to build up body stores in the preterm infant and achieve positive retention in full-term infants, balance studies were completed in 38 preterm, full-term, and full-term SGA infants who received complete intravenously delivered nutrient formulations excluding zinc and copper. Zinc as ZnSo4 and copper as CuCl2 were then added to individual infants' formulations, with intakes ranging from 91 to 824 micrograms/kg/day (zinc) and 8 to 92 micrograms/kg/day (copper). Samples of infusate as well as urine, stool, and aspirate were collected for 72 hours and analyzed for zinc and copper by atomic absorption spectrophotometry. Zinc and copper retention correlated significantly with intake (r = 0.89; 0.82, P less than 0.01) and were independent of gestational age, postnatal age, and birth weight. In full-term and full-term SGA infants, intakes of zinc at greater than 150 and copper at greater than 16 micrograms/kg/day were adequate to replace ongoing losses and prevent acute deficiencies. The dosage for copper is similar to the current recommendation of the American Medical Association; the zinc dosage is 50% higher. Preterm infants receiving intakes of zinc at 438 and copper at 63 micrograms/kg/day achieve in utero retention rates. These dosages are significantly higher than AMA recommendations. Both combinations can be delivered by peripheral or central line without complications.     

Zinc deficiency in rapidly growing preterm infants

Symptomatic zinc deficiency was observed in a 24-week gestation, 640g birthweight infant fed exclusively with maternal breast milk. Our hypothesis was that subclinical Zn deficiency is not uncommon in very low birthweight infants because fortified human milk and preterm formula may contain little Zn. Zinc serum concentrations determined in 26 consecutive very low birthweight infants (gestational age 23-32, median 27 weeks), prior to discharge, at a chronological age of 37-121 (median 72) d, were found between 1.0 and 14.0 (median 6.4) μmol/l, in 14 infants they were below the normal range of 7.6-15.0μmol/l. Serum alkaline phosphatase and iron intake did not correlate with Zn concentrations. Nutritional supply of Zn and other trace elements by breast milk fortifiers and infant formulas currently used in Germany does not appear to meet the demands of rapidly growing extremely low birthweight infants during the first months of life.     

Body composition in infants with chronic lung disease after treatment with dexamethasone

The aim of this study was to study the effect of chronic lung disease (CLD) and dexamethasone treatment on body composition in preterm infants (birthweight < 1500 g). In addition, anthropometric measurement of body composition were compared with dual-energy X-ray absorptiometry (DXA). Fourteen preterm infants with CLD and a comparison group of 18 preterm infants were studied until 3 mo corrected age. CLD infants received approximately 20 kcal kg-1 per day extra nutritional intake during dexamethasone treatment until term. At term no differences were found between CLD and no CLD infants for percentage bone mass (1.4 +/- 0.2 vs 1.4 +/- 0.1%), fat mass (18.7 +/- 4.5 vs 17.4 +/- 3.5%), lean body mass (79.9 +/- 4.6 vs 81.2 +/- 3.5%) or bone mineral density (0.15 +/- 0.02 vs 0.15 +/- 0.01%). At 3 mo corrected age both groups were also similar for bone mass (1.6 +/- 0.1 vs 1.6 +/- 0.2%), fat mass (22.6 +/- 5.5 vs 24.5 +/- 5.7%), lean body mass (75.8 +/- 5.7 vs 74.0 +/- 5.8%) and bone mineral density (0.20 +/- 0.02 vs 0.20 +/- 0.01%). All anthropometric measurements showed a high correlation with body composition. However, calculated fat mass was 56.7 +/- 8.8% lower than fat mass measured with DXA. CONCLUSION: Body composition at term and 3 mo corrected age in preterm infants treated with dexamethasone for CLD, who received extra caloric intake until term, did not differ from that in preterm infants without CLD.