Salt sensitivity of children with low birth weight

Compromised intrauterine fetal growth leading to low birth weight (<2500 g) is associated with adulthood renal and cardiovascular disease. The aim of this study was to assess the effect of salt intake on blood pressure (salt sensitivity) in children with low birth weight. White children (n=50; mean age: 11.3+/-2.1 years) born with low (n=35) or normal (n=15) birth weight and being either small or appropriate for gestational age (n=25 in each group) were investigated. The glomerular filtration rate was calculated using the Schwartz formula, and renal size was measured by ultrasound. Salt sensitivity was assigned if mean 24-hour blood pressure increased by >or=3 mm Hg on a high-salt diet as compared with a controlled-salt diet. Baseline office blood pressure was higher and glomerular filtration rate lower in children born with low birth weight as compared with children born at term with appropriate weight (P<0.05). Salt sensitivity was present in 37% and 47% of all of the low birth weight and small for gestational age children, respectively, higher even than healthy young adults from the same region. Kidney length and volume (both P<0.0001) were reduced in low birth weight children. Salt sensitivity inversely correlated with kidney length (r(2)=0.31; P=0.005) but not with glomerular filtration rate. We conclude that a reduced renal mass in growth-restricted children poses a risk for a lower renal function and for increased salt sensitivity. Whether the changes in renal growth are causative or are the consequence of the same abnormal "fetal programming" awaits clarification.

Does the choice of bottle nipple affect the oral feeding performance of very-low-birthweight (VLBW) infants?

BACKGROUND: There is a continuous debate regarding the best bottle nipple to be used to enhance the bottle-feeding performance of a preterm infant. Aim: To verify that feeding performance can be improved by using the bottle nipple with the physical characteristics that enhance infants' sucking skills. METHODS: Ten "healthy" VLBW infants (941+/-273 g) were recruited. Feeding performance was monitored at two time periods, when taking 1-2 and 6-8 oral feedings/d. At each time and within 24 h, performance was monitored using three different bottle nipples offered in a randomized order. Rate of milk transfer (ml/min) was the primary outcome measure. The sucking skills monitored comprised stage of sucking, suction amplitude, and duration of the generated negative intraoral suction pressure. RESULTS: At both times, infants demonstrated a similar rate of milk transfer among all three nipples. However, the stage of sucking, suction amplitude, and duration of the generated suction were significantly different between nipples at 1-2, but not 6-8 oral feedings/d.CONCLUSION: We did not identify a particular bottle nipple that enhanced bottle feeding in healthy VLBW infants. Based on the notion that afferent sensory feedback may allow infants to adapt to changing conditions, we speculate that infants can modify their sucking skills in order to maintain a rate of milk transfer that is appropriate with the level of suck-swallow-breathe coordination achieved at a particular time. Therefore, it is proposed that caretakers should be more concerned over monitoring the coordination of suck-swallow-breathe than over the selection of bottle nipples.

Ethnic/racial diversity, maternal stress, lactation and very low birthweight infants.

OBJECTIVE: (1) To compare maternal characteristics and psychological stress profile among African-American, Caucasian and Hispanic mothers who delivered very low birthweight infants. (2) To investigate associations between psychosocial factors, frequency of milk expression, skin-to-skin holding (STS), and lactation performance, defined as maternal drive to express milk and milk volume. STUDY DESIGN: Self-reported psychological questionnaires were given every 2 weeks after delivery over 10 weeks. Milk expression frequency, STS, and socioeconomic variables were collected. RESULT: Infant birthweight, education, and milk expression frequency differed between groups. Trait anxiety, depression and parental stress in a neonatal intensive care unit (PSS:NICU) were similar. African-American and Caucasian mothers reported the lowest scores in state anxiety and social desirability, respectively. Maternal drive to express milk, measured by maintenance of milk expression, correlated negatively with parental role alteration (subset of PSS:NICU) and positively with infant birthweight and STS. Milk volume correlated negatively with depression and positively with milk expression frequency and STS. CONCLUSION: Differences between groups were observed for certain psychosocial factors. The response bias to self-reported questionnaires between groups may not provide an accurate profile of maternal psychosocial profile. With different factors correlating with maintenance of milk expression and milk volume, lactation performance can be best enhanced with a multi-faceted intervention program, incorporating parental involvement in infant care, close awareness and management of maternal mental health, and encouragement for frequent milk expression and STS.

Aggressive vs. conservative phototherapy for infants with extremely low birth weight.

BACKGROUND: It is unclear whether aggressive phototherapy to prevent neurotoxic effects of bilirubin benefits or harms infants with extremely low birth weight (1000 g or less). METHODS: We randomly assigned 1974 infants with extremely low birth weight at 12 to 36 hours of age to undergo either aggressive or conservative phototherapy. The primary outcome was a composite of death or neurodevelopmental impairment determined for 91% of the infants by investigators who were unaware of the treatment assignments. RESULTS: Aggressive phototherapy, as compared with conservative phototherapy, significantly reduced the mean peak serum bilirubin level (7.0 vs. 9.8 mg per deciliter [120 vs. 168 micromol per liter], P<0.01) but not the rate of the primary outcome (52% vs. 55%; relative risk, 0.94; 95% confidence interval [CI], 0.87 to 1.02; P=0.15). Aggressive phototherapy did reduce rates of neurodevelopmental impairment (26%, vs. 30% for conservative phototherapy; relative risk, 0.86; 95% CI, 0.74 to 0.99). Rates of death in the aggressive-phototherapy and conservative-phototherapy groups were 24% and 23%, respectively (relative risk, 1.05; 95% CI, 0.90 to 1.22). In preplanned subgroup analyses, the rates of death were 13% with aggressive phototherapy and 14% with conservative phototherapy for infants with a birth weight of 751 to 1000 g and 39% and 34%, respectively (relative risk, 1.13; 95% CI, 0.96 to 1.34), for infants with a birth weight of 501 to 750 g. CONCLUSIONS: Aggressive phototherapy did not significantly reduce the rate of death or neurodevelopmental impairment. The rate of neurodevelopmental impairment alone was significantly reduced with aggressive phototherapy. This reduction may be offset by an increase in mortality among infants weighing 501 to 750 g at birth. (ClinicalTrials.gov number, NCT00114543.)

Less invasive ventilation in extremely low birth weight infants from 1997 to 2011: survey versus evidence.

UNLABELLED Evidence for target values of arterial oxygen saturation (SaO2), CO2, and pH has changed substantially over the last 20 years. A representative survey concerning treatment strategies in extremely low-birth-weight infants (ELBW) was sent to all German neonatal intensive care units (NICUs) treating ELBW infants in 1997. A follow-up survey was conducted in 2011 and sent to all NICUs in Germany, Austria, and Switzerland. During the observation period, NICUs targeting SaO2 of 80, 85, and 90 % have increased, while units aiming for 94 and 96 % decreased (all p < 0.001). Similarly, NICUs aiming for pH 7.25 or lower increased, while 7.35 or higher decreased (both p < 0.001). Furthermore, more units targeted a CO2 of 50 mmHg (7.3 kPa) or higher (p < 0.001), while fewer targeted 40 or 35 mmHg (p < 0.001). Non-invasive ventilation (NIV) was used in 80.2 % of NICUs in 2011. The most frequently used ventilation modes were synchronized intermittent mandatory ventilation (SIMV) (67.5 %) and intermittent positive pressure ventilation (IPPV) (59.7 %) in 1997 and SIMV (77.2 %) and synchronized intermittent positive pressure ventilation (SIPPV) (26.8 %) in 2011. NICUs reporting frequent or always use of IPPV decreased to 11.0 % (p < 0.001). SIMV (77.2 %) and SIPPV (26.8 %) did not change from 1997 to 2011, while high-frequency oscillation (HFO) increased from 9.1 to 19.7 % (p = 0.018). Differences between countries, level of care, and size of the NICU were minimal. CONCLUSIONS Target values for SaO2 decreased, while CO2 and pH increased significantly during the observation period. Current values largely reflect available evidence at time of the surveys. WHAT IS KNOWN • Evidence concerning target values of oxygen saturation, CO 2 , and pH in extremely low-birth-weight infants has grown substantially. • It is not known to which extent this knowledge is transferred into clinical practice and if treatment strategies have changed. WHAT IS NEW • Target values for oxygen saturation in ELBW infants decreased between 1997 and 2011 while target values for CO 2 and pH increased. • Similar treatment strategies existed in different countries, hospitals of different size, or university versus nonuniversity hospitals in 2011.

Contribution of parental blood pressures to association between low birth weight and adult high blood pressure: cross sectional study

Objective: To examine the possibility that low birth weight is a feature of the inherited predisposition to high blood pressure.

Investigation of H19/RsaI Polymorphism in Children With Low Birth Weight in Pernambuco, Brazil

Background: H19 is a strong candidate gene for influencing birth weight variation and is exclusively imprinted maternally. In an attempt to understand the relationship of this gene polymorphism with low birth weight children, we investigated association of H19/RsaI polymorphism with low birth weight and normal birth weight in children and their mothers. Objectives: The aim of our study was to establish the association between H19 gene polymorphism and LW in children born in Pernambuco, state of Brazil. Patients and Methods: It were selected 89 children, 40 low birth weight (LW) and 49 normal birth weight (NW) and 71 mothers (40 mothers of newborns NW and 31 mothers of newborns LW) attended at Dom Malan Hospital, Petrolina, Pernambuco - Brazil. Peripheral blood samples were collected from patients and genomic DNA was extracted and detected by electrophoresis agarose gel, stained by Blue Green Loading Dye. DNA PCR amplification was done using the primers H1 (sense) and H3 (antisense). PCR products were digested with RsaI and electrophoresed on agarose gel stained by ethidium bromide. Statistical analyses were performed using the program BioEstat version 5.0. Results: The RsaI polymorphism in the H19 gene showed that genotype frequencies did not differ statistically between low birth weight (AA = 12.5%, AB = 45%, BB = 42.5%) and control (AA = 8.6% AB = 36.73%, BB= 55.10% groups) and the allele frequencies were not significantly different (P = 0.2897). We also did not observe any association between maternal H19 allele polymorphism and low birth weight newborns (P =0.7799) or normal birth weight children (P = 0.8976). Conclusions: The small size of sample may be the explanation for these results; future studies with more patients are needed to confirm the effect of H19/RsaI polymorphism on birth weight of LW newborns.

Antibiotic Therapy for Very Low BirthWeigh Newborns in NICU

Background: Prolonged empiric antibiotics therapy in neonates results in several adverse consequences including widespread antibiotic resistance, late onset sepsis (LOS), necrotizing enterocolitis (NEC), prolonged hospital course (HC) and increase in mortality rates. Objectives: To assess the risk factors and the outcome of prolonged empiric antibiotic therapy in very low birth weight (VLBW) newborns. Materials and Methods: Prospective study in VLBW neonates admitted to NICU and survived > 2 W, from July 2011 - June 2012. All relevant perinatal and postnatal data including duration of antibiotics therapy (Group I < 2W vs Group II > 2W) and outcome up to the time of discharge or death were documented and compared. Results: Out of 145 newborns included in the study, 62 were in group I, and 83 in Group II. Average duration of antibiotic therapy was 14 days (range 3 - 62 days); duration in Group I and Group II was 102.3 vs 25.510.5 days. Hospital stay was 22.311.5 vs 44.3 14.7 days, respectively. Multiple regression analysis revealed following risk factors as significant for prolonged empiric antibiotic therapy: VLBW especially < 1000 g, (P < 0.001), maternal Illness (P = 0.003), chorioamnionitis (P = 0.048), multiple pregnancy (P = 0.03), non-invasive ventilation (P < 0.001) and mechanical ventilation (P < 0.001). Seventy (48.3%) infants developed LOS; 5 with NEC > stage II, 12 (8.3%) newborns died. Infant mortality alone and with LOS/NEC was higher in group II as compared to group I (P < 0.002 and < 0.001 respectively). Conclusions: Prolonged empiric antibiotic therapy caused increasing rates of LOS, NEC, HC and infant mortality

Effect of type and timing of oil supplements to sows during pregnancy on the growth performance and endocrine profile of low and normal birth weight offspring

Eighty-eight multiparous sows were used to evaluate whether type and timing of oil supplementation during gestation influences the incidence of low birth weight (LBW). Sows were allocated (eight per treatment) commercial sow pellets (3 kg/d; control diet) or an experimental diet consisting of control diet plus 10 % extra energy in the form of excess pellets, palm oil, olive oil (OO), sunflower oil (SO) or fish oil; experimental diets were fed during either the first half (G1) or second half (G2) of gestation. Growth performance and endocrine profile of LBW ( < 1·09 kg) and normal birth weight (NBW; 1·46–1·64 kg) offspring were compared. Maternal dietary supplementation altered the distribution curve for piglet birth weight. SOG1 sows had a greater proportion of LBW piglets (P < 0·05), whilst it was reduced in the OOG1 group (P < 0·05). Growth rate of LBW piglets was lower compared with their NBW siblings (P < 0·05) when dietary supplementation was offered in G2 but were similar for G1. At birth, LBW offspring of supplemented animals possessed more fat compared with the control group (P < 0·05); LBW offspring of control animals exhibited a more rapid decline in fat free mass/kg prior to weaning. Plasma metabolites and insulin concentrations were influenced by maternal diet and birth weight. In conclusion, maternal dietary supplementation altered the distribution of piglet birth weights and improved the energy status of LBW piglets. Supplementation with MUFA during G1 reduced the incidence of LBW, whereas PUFA had the reverse effect.

Low and high birth weight as risk factors for obesity among 4 to 5 year old Australian children : does gender matter?

Studies testing whether birth weight and childhood obesity differ by gender are lacking. We aimed to describe the relationship between birth weight and childhood overweight/obesity and investigate the influence that gender has on this relationship among 4 to 5-year-old children. We performed a secondary analysis of an Australian nationally representative cross-sectional study in 4 to 5-year-old children. The main outcome measure was child overweight and obesity. We found that low birth weight (LBW) was associated with lower risk of overweight/obesity among girls at 4–5 years before (OR 0.50, 95%CI 0.32, 0.77) and after adjusting for socio-demographic factors (OR 0.51 95%CI 0.33, 0.80) and ethnicity (OR 0.52, 95%CI 0.33, 0.81) but was not associated with child overweight/obesity among boys before or after adjustment. High birth weight (HBW) was associated with a higher risk of overweight/obesity among both girls (adjusted OR: 1.76, 95%CI 1.12, 2.78) and boys (adjusted OR: 2.42 95% CI 2.06, 2.86). Conclusion: There are gender differences in the association of birth weight with child overweight/obesity. HBW was associated with a higher risk of child overweight/obesity in boys and girls before and after adjustment for socio-demographic factors. However, LBW was associated with a lower risk of child overweight/obesity in girls but not in boys. These gender differences need to be considered when planning interventions to reduce child overweight/obesity.

School entry age outcomes for infants with birth weight ≤ 800 grams

To evaluate the mortality and long-term morbidity rates of extremely low birth weight (ELBW) infants admitted to neonatal intensive care units (NICUs).

Language development at 3 years in pre-term children of birth weight below 1000 g

Language development at 3 years of pre-term children born below 1000 g birth weight was compared with full-term controls matched for social background. The pre-term group used less complex expressive language and showed lower receptive understanding, auditory memory and verbal reasoning. Language outcome was related to intraventricular haemorrhage but not to global indication of postnatal illness such as number of days on the ventilator. Average verbal intelligence in environmentally low risk, extremely low birth weight children is an insufficient indicator of complex language functioning.

Still Unequal at Birth: Birth Weight, Socioeconomic Status and Outcomes at Age 9

The prevalence of low birth weight is an important aspect of public health which has been linked to increased risk of infant death, increased cost of care, and a range of later life outcomes. Using data from a new Irish cohort study, I document the relationship between birth weight and socio-economic status. The association of maternal education with birth weight does not appear to be due to the timing of birth or complications during pregnancy, even controlling for a wide range of background characteristics. However, results do suggest intergenerational persistence in the transmission of poor early life conditions. Birth weight predicts a number of outcomes at age 9, including test scores, hospital stays and health. An advantage of the data is that I am able to control for a number of typically unmeasured variables. I determine whether parental investments (as measured by the quality of interaction with the child, parenting style, or school quality) mediate the association between birth weight and later indicators. For test scores, there is evidence of non-linearity, and boys are more adversely affected than girls. I also consider whether there are heterogeneous effects by ability using quantile regression. These results are consistent with a literature which finds that there is a causal relationship between early life conditions and later outcomes.