A Quantitative Review of Mortality and Developmental Disability in Extremely Premature Newborns
ABSTRACT To summarize the literature on mortality rates and prevalences of major neurodevelopmental disabilities and to examine trends of these outcomes over time in extremely premature neonates.
MEDLINE was used to search the English literature for studies published since 1970 reporting on both mortality and disability in infants born at or before 26 weeks' gestation (extremely immature [EI] cohort), with a birth weight of 800 g or less (extremely small [ES] cohort), or subgroups of these.
Studies were included in the analysis if all of the following were reported: mortality; direct examination of 75% or more of the survivors; and the proportion of patients with at least 1 of the following disabilities: cerebral palsy, mental retardation, blindness, and deafness. Studies reporting cohorts included as a subset of cohorts in another study were excluded. Forty-two studies providing mortality and disability data for 20 cohorts of 4116 EI infants and 38 cohorts of 4345 ES infants born after 1972 met the inclusion criteria.
Data were abstracted from all studies that met these criteria by two of us (J.M.L. and D.E.W.), independently; the data were then cross-checked to ensure accuracy.
Survival averaged 41% for EI infants and 30% for ES infants, and it increased significantly with time. In contrast to mortality, the prevalences of major neurodevelopmental disabilities among survivors have not changed over time. The most common major disability was mental retardation, found in 14% of EI and ES survivors. Cerebral palsy was found in 12% of EI survivors and 8% of ES survivors, blindness was found in 8% of EI and ES survivors, and deafness was found in 3% of EI and ES survivors. Overall, 22% of EI survivors and 24% of ES survivors were classified as having at least 1 major disability. Each 100 EI or ES livebirths yielded 7 children with major disabilities; this prevalence was correlated with survival across cohorts.
The prevalence of disabilities had not changed among EI or ES survivors with increasing survival. However, increasing survival of these infants has resulted in a steadily increasing prevalence of children with disabilities.
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ABSTRACT: Preterm birth is defined as any delivery before 37 complete weeks of gestation. It is a universal challenge in the field of obstetrics owing to its high rate of mortality, long-term morbidity, associated human suffering and economic burden. In the United States, about 12.18% deliveries in 2009 were preterm, producing an exorbitant cost of $5.8 billion. Infection-associated premature rupture of membranes (PROM) accounts for 40% of extremely preterm births (<28 weeks of gestation). Major research efforts are directed towards improving the understanding of the pathophysiology of preterm birth and ways to prevent or at least postpone delivery. Endothelin-1 (ET-1) is a potent vasoconstrictor that plays a significant role in infection-triggered preterm birth. Its involvement in a number of pathological mechanisms and its elevation in preterm delivered amniotic fluid samples implicate it in preterm birth. Sphingosine kinase (SphK) is a ubiquitous enzyme responsible for the production of sphingosine-1-phosphate (S1P). S1P acts as second messenger in a number of cell proliferation and survival pathways. SphK is found to play a key role in ET-1 mediated myometrial contraction. This review highlights SphK as a prospective target with great potential to prevent preterm birth.Obstetrics and Gynecology International 05/2013; 2013:302952. DOI:10.1155/2013/302952
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ABSTRACT: Extremely low and very low gestational age (ELGA and VLGA) constitutes a risk factor for development even in absence of cerebral damage, as an immature central nervous system is exposed to invasive and inadequate stimulation. We tested the hypothesis that GA impacts developmental outcomes and trajectories of preterms without major cerebral damage in the first 2 years of life, expecting poorer developmental outcomes and higher rate of impairment with the decreasing of GA. We also evaluated whether GA, together with developmental outcomes in the first year of life, was related to developmental outcomes at 24 months. Eighty-eight infants, divided into three GA groups (ELGA: ≤28 weeks; VLGA: 29-32 weeks; full term: >37 weeks) were assessed longitudinally at 6, 12, 18 and 24 months using the Griffiths Mental Development Scales. Use of a repeated measure multivariate analysis of variance resulted in several significant findings. GA was associated with the developmental quotient (DQ) scores (P= 0.006); and locomotor (P < 0.001), eye and hand co-ordination (P= 0.016) and performance (P= 0.040) sub-scale quotient (SQ) scores; age of evaluation was also associated with DQ scores (P= 0.002), and locomotor (P < 0.001) and performance (P < 0.001) SQ scores. In particular, ELGAs exhibited lower DQ and SQ scores compared with the VLGA and full-term groups; some ELGAs showed mild, moderate or severe cognitive impairments, while few VLGAs mild impairments. Linear regression analysis showed that GA (P= 0.034) and 12-month developmental outcome (P < 0.001) were related to 24-month developmental outcome. Different developmental trajectories emerged in relation to GA, with poorer developmental outcomes and higher rates of impairment in ELGAs and few mild impairments in VLGAs. The relevance of taking into account both GA and repeated assessments in the first 2 years of life was shown.Child Care Health and Development 01/2011; 37(1):26-36. DOI:10.1111/j.1365-2214.2010.01143.x · 1.83 Impact Factor
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