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Postnatal Factors (postnatal + factor)
Selected AbstractsBronchopulmonary dysplasia and brain white matter damage in the preterm infant: a complex relationshipPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 6 2009Luigi Gagliardi Summary We analysed the relationship between bronchopulmonary dysplasia (BPD) and brain white matter damage (WMD) in very preterm infants, adjusting for common risk factors and confounders. We studied a cohort of infants <32 weeks gestational age (GA) and <1500 g, admitted to 12 hospitals in Northern Italy in 1999,2002. The association between BPD and WMD was estimated by generalised estimating equations and conditional logistic models, adjusting for centre, GA, propensity score for prolonged ventilation and other potential confounders. Directed acyclic graphs (DAG) were used to depict the underlying causal structure and guide analysis. Of the 1209 infants reaching 36 weeks, 192 (15.8%) developed BPD (supplemental oxygen at 36 weeks) and 88 (7.3%) ultrasound-defined WMD (cystic periventricular leukomalacia). In crude analysis, BPD was a strong risk factor for WMD [odds ratio (OR) = 5.9]. With successive adjustments, the OR progressively decreased to 3.88 when adjusting for GA, to 2.72 adding perinatal risk factors, and further down to 2.16 [95% confidence interval 1.1, 3.9] when ventilation was also adjusted for. Postnatal factors did not change the OR. Significant risk factors for WMD, in addition to BPD, were a low GA, a lower Apgar score, a higher illness severity score, ventilation and early-onset sepsis, while antenatal steroids, being small for GA, and surfactant were associated with a reduced risk. In conclusion, our data suggest that BPD is associated with an increased risk of WMD; most of the effect is due to shared risk factors and causal pathways. DAGs helped clarify the complex confounding of this scenario. [source] Impact of chorioamnionitis and preeclampsia on neurodevelopmental outcome in preterm infants below 32 weeks gestational ageACTA PAEDIATRICA, Issue 10 2010Luregn J Schlapbach Abstract Aim:, Intrauterine conditions may interfere with foetal brain development. We compared the neurodevelopmental outcome between infants <32 weeks gestational age after maternal preeclampsia or chorioamnionitis and controls. Methods:, Case-control study on infants with maternal preeclampsia, chorioamnionitis and controls (each n = 33) matched for gestational age. Neurodevelopment at 2 years was assessed with the Bayley Scales of Infant Development II. Results:, A total of 99 infants were included with a median gestational age of 29 weeks (range 25,32). Median mental developmental index (MDI) was 96 in the control, 90 in the chorioamnionitis and 86 in the preeclampsia group. Preeclampsia infants had a lower MDI compared with the control group (univariate p = 0.021, multivariate p = 0.183) and with the chorioamnionitis group (univariate p = 0.242; multivariate p = 0.027). Median psychomotor index was 80.5 in the control, 80 in the preeclampsia and 85 in the chorioamnionitis group and was not different between these three groups (p > 0.05). Chorioamnionitis or preeclampsia exposure was not associated with major neurodevelopmental impairments (cerebral palsy, MDI<70, PDI<70). Conclusion:, The results of this preliminary study suggest that preeclampsia and chorioamnionitis play a relatively minor role among risk factors for adverse neurodevelopment outcome. Postnatal factors such as ventilation and bronchopulmonary dysplasia may have a greater impact on neurodevelopmental outcome. [source] Association between pacifier use and breast-feeding, sudden infant death syndrome, infection and dental malocclusionINTERNATIONAL JOURNAL OF EVIDENCE BASED HEALTHCARE, Issue 6 2005Ann Callaghan RN RM BNurs(Hons) Executive summary Objective, To critically review all literature related to pacifier use for full-term healthy infants and young children. The specific review questions addressed are: What is the evidence of adverse and/or positive outcomes of pacifier use in infancy and childhood in relation to each of the following subtopics: ,breast-feeding; ,sudden infant death syndrome; ,infection; ,dental malocclusion. Inclusion criteria, Specific criteria were used to determine which studies would be included in the review: (i) the types of participants; (ii) the types of research design; and (iii) the types of outcome measures. To be included a study has to meet all criteria. Types of participants,The participants included in the review were healthy term infants and healthy children up to the age of 16 years. Studies that focused on preterm infants, and infants and young children with serious illness or congenital malformations were excluded. However, some total population studies did include these children. Types of research design, It became evident early in the review process that very few randomised controlled trials had been conducted. A decision was made to include observational epidemiological designs, specifically prospective cohort studies and, in the case of sudden infant death syndrome research, case,control studies. Purely descriptive and cross-sectional studies were excluded, as were qualitative studies and all other forms of evidence. A number of criteria have been proposed to establish causation in the scientific and medical literature. These key criteria were applied in the review process and are described as follows: (i) consistency and unbiasedness of findings; (ii) strength of association; (iii) temporal sequence; (iv) dose,response relationship; (v) specificity; (vi) coherence with biological background and previous knowledge; (vii) biological plausibility; and (viii) experimental evidence. Studies that did not meet the requirement of appropriate temporal sequencing of events and studies that did not present an estimate of the strength of association were not included in the final review. Types of outcome measures,Our specific interest was pacifier use related to: ,breast-feeding; ,sudden infant death syndrome; ,infection; ,dental malocclusion. Studies that examined pacifier use related to procedural pain relief were excluded. Studies that examined the relationship between pacifier use and gastro-oesophageal reflux were also excluded as this information has been recently presented as a systematic review. Search strategy, The review comprised published and unpublished research literature. The search was restricted to reports published in English, Spanish and German. The time period covered research published from January 1960 to October 2003. A protocol developed by New Zealand Health Technology Assessment was used to guide the search process. The search comprised bibliographic databases, citation searching, other evidence-based and guidelines sites, government documents, books and reports, professional websites, national associations, hand search, contacting national/international experts and general internet searching. Assessment of quality, All studies identified during the database search were assessed for relevance to the review based on the information provided in the title, abstract and descriptor/MeSH terms, and a full report was retrieved for all studies that met the inclusion criteria. Studies identified from reference list searches were assessed for relevance based on the study title. Keywords included: dummy, dummies, pacifier(s), soother(s), comforter(s), non-nutritive sucking, infant, child, infant care. Initially, studies were reviewed for inclusion by pairs of principal investigators. Authorship of articles was not concealed from the reviewers. Next, the methodological quality of included articles was assessed independently by groups of three or more principal investigators and clinicians using a checklist. All 20 studies that were accepted met minimum set criteria, but few passed without some methodological concern. Data extraction, To meet the requirements of the Joanna Briggs Institute, reasons for acceptance and non-acceptance at each phase were clearly documented. An assessment protocol and report form was developed for each of the three phases of review. The first form was created to record investigators' evaluations of studies included in the initial review. Those studies that failed to meet strict inclusion criteria were excluded at this point. A second form was designed to facilitate an in-depth critique of epidemiological study methodology. The checklist was pilot tested and adjustments were made before reviewers were trained in its use. When reviewers could not agree on an assessment, it was passed to additional reviewers and discussed until a consensus was reached. At this stage, studies other than cohort, case,control and randomised controlled trials were excluded. Issues of clarification were also addressed at this point. The final phase was that of integration. This phase, undertaken by the principal investigators, was assisted by the production of data extraction tables. Through a process of trial and error, a framework was formulated that adequately summarised the key elements of the studies. This information was tabulated under the following headings: authors/setting, design, exposure/outcome, confounders controlled, analysis and main findings. Results, With regard to the breast-feeding outcome, 10 studies met the inclusion criteria, comprising two randomised controlled trials and eight cohort studies. The research was conducted between 1995 and 2003 in a wide variety of settings involving research participants from diverse socioeconomic and cultural backgrounds. Information regarding exposure and outcome status, and potential confounding factors was obtained from: antenatal and postnatal records; interviews before discharge from obstetric/midwifery care; post-discharge interviews; and post-discharge postal and telephone surveys. Both the level of contact and the frequency of contact with the informant, the child's mother, differed widely. Pacifier use was defined and measured inconsistently, possibly because few studies were initiated expressly to investigate its relationship with breast-feeding. Completeness of follow-up was addressed, but missing data were not uniformly identified and explained. When comparisons were made between participants and non-participants there was some evidence of differential loss and a bias towards families in higher socioeconomic groups. Multivariate analysis was undertaken in the majority of studies, with some including a large number of sociodemographic, obstetric and infant covariates and others including just maternal age and education. As might be expected given the inconsistency of definition and measurement, the relationship between pacifier use and breast-feeding was expressed in many different ways and a meta-analysis was not appropriate. In summary, only one study did not report a negative association between pacifier use and breast-feeding duration or exclusivity. Results indicate an increase in risk for a reduced overall duration of breast-feeding from 20% to almost threefold. The data suggest that very infrequent use may not have any overall negative impact on breast-feeding outcomes. Six sudden infant death syndrome case,control studies met the criteria for inclusion. The research was conducted with information gathered between 1984 and 1999 in Norway, UK, New Zealand, the Netherlands and USA. Exposure information was obtained from a variety of sources including: hospital and antenatal records, death scene investigation, and interview and questionnaire. Information for cases was sought within 2 days after death, within 2,4 weeks after death and in one study between 3 and 11 years after death. Information for controls was sought from as early as 4 days of a nominated sudden infant death syndrome case, to between 1 and 7 weeks from the case date, and again in one study some 3,11 years later. In the majority of the studies case ascertainment was determined by post-mortem. Pacifier use was again defined and measured somewhat inconsistently. All studies controlled for confounding factors by matching and/or using multivariate analysis. Generally, antenatal and postnatal factors, as well as infant care practices, and maternal, family and socioeconomic issues were considered. All five studies reporting multivariate results found significantly fewer sudden infant death syndrome cases used a pacifier compared with controls. That is, pacifier use was associated with a reduced incidence of sudden infant death syndrome. These results indicate that the risk of sudden infant death syndrome for infants who did not use a pacifier in the last or reference sleep was at least twice, and possibly five times, that of infants who did use a pacifier. Three studies reported a moderately sized positive association between pacifier use and a variety of infections. Conversely, one study found no positive association between pacifier use at 15 months of age and a range of infections experienced between the ages of 6 and 18 months. Given the limited number of studies available and the variability of results, no meaningful conclusions could be drawn. Five cohort studies and one case,control study focused on the relationship between pacifier use and dental malocclusion. Not one of these studies reported a measure of association, such as an estimate of relative risk. It was therefore not possible to include these studies in the final review. Implications for practice, It is intended that this review be used as the basis of a ,best practice guideline', to make health professionals aware of the research evidence concerning these health and developmental consequences of pacifier use, because parents need clear information on which they can base child care decisions. With regard to the association between pacifier use and infection and dental malocclusion it was found that, due to the paucity of epidemiological studies, no meaningful conclusion can be drawn. There is clearly a need for more epidemiological research with regard to these two outcomes. The evidence for a relationship between pacifier use and sudden infant death syndrome is consistent, while the exact mechanism of the effect is not well understood. As to breast-feeding, research evidence shows that pacifier use in infancy is associated with a shorter duration and non-exclusivity. It is plausible that pacifier use causes babies to breast-feed less, but a causal relationship has not been irrefutably proven. Because breast-feeding confers an important advantage on all children and the incidence of sudden infant death syndrome is very low, it is recommended that health professionals generally advise parents against pacifier use, while taking into account individual circumstances. [source] Cohort variation in offspring growth and survival: prenatal and postnatal factors in a late-maturing viviparous snakeJOURNAL OF ANIMAL ECOLOGY, Issue 3 2010Jean-Pierre Baron Summary 1. Recruitment to adulthood plays an important role in the population dynamics of late-maturing organisms as it is usually variable. Compared to birds and mammals, few studies assessing the contributions to this variation of environmental factors, offspring traits and maternal traits have been carried out for late-maturing snakes. 2. Cohort variation in recruitment through offspring growth and survival in the meadow viper (Vipera ursinii ursinii) was evaluated from 13 years of mark,recapture data collected at Mont Ventoux, France. In this species, females are mature at the age of 4,6 years and adult survival and fecundity rates are high and constant over time. 3. Offspring were difficult to catch during the first 3 years of their lives, but their mean annual probability of survival was reasonably high (0·48 ± 0·11 SE). Mass and body condition at birth (mass residuals) varied significantly between years, decreased with litter size, and increased with maternal length. 4. Cohorts of offspring in better condition at birth grew faster, but offspring growth was not affected by sex, habitat or maternal traits. 5. Survival varied considerably between birth cohorts, some cohorts having a high-survival rate and others having essentially no survivors. No difference in mass or body condition at birth was found between cohorts with ,no survival' and ,good survival'. However, offspring survival in cohorts with good survival was positively correlated with mass at birth and negatively correlated with body condition at birth. 6. Thus, variation in offspring performance was influenced by direct environmental effects on survival and indirect environmental effects on growth, mediated by body condition at birth. Effects of maternal traits were entirely channelled through offspring traits. [source] PERINATAL AND CHILDHOOD PRECURSORS OF ADULT CARDIOVASCULAR DISEASECLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 2007Lawrence Beilin SUMMARY 1Longitudinal studies from the US, Australia and Europe have demonstrated tracking of childhood risk factors for cardiovascular disease from adolescence into adult life. These factors include obesity, blood cholesterol levels, blood pressure and measures of insulin resistance. Worldwide increases in childhood obesity and overweight are already resulting in increases in adolescent diabetes and are likely to translate into earlier onset hypertension and cardiovascular disease in adults. 2Low birth weight has also been associated with increased risk of adult cardiovascular disease, diabetes and high blood pressure, but there is considerable debate as to the relative importance of pre- and postnatal influences. 3These issues are discussed in the context of results of a longitudinal cohort study of cardiovascular and metabolic risk factors in Western Australia, the ,Raine' childhood cohort, which showed that in a well-nourished Australian population at age 8 there was a U-shaped relationship between birth weight and a cluster of factors predisposing to adult cardiovascular disease, with postnatal weight gain being the dominant factor. 4Future public health programmes should focus on both pre- and early postnatal factors predisposing to obesity, hypertension and diabetes. 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