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1.
JAMA Netw Open ; 3(6): e206757, 2020 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-32520359

RESUMEN

Importance: Racial/ethnic disparities in quality of care among extremely preterm infants are associated with adverse outcomes. Objective: To assess whether racial/ethnic disparities in major outcomes and key care practices were changing over time among extremely preterm infants. Design, Setting, and Participants: This observational cohort study used prospectively collected data from 25 US academic medical centers. Participants included 20 092 infants of 22 to 27 weeks' gestation with a birth weight of 401 to 1500 g born at centers participating in the National Institute of Child Health and Human Development Neonatal Research Network from 2002 to 2016. Of these infants, 9316 born from 2006 to 2014 were eligible for follow-up at 18 to 26 months' postmenstrual age (excluding 5871 infants born before 2006, 2594 infants born after 2014, and 2311 ineligible infants including 64 with birth weight >1000 g and 2247 infants with gestational age >26 6/7 weeks), of whom 745 (8.0%) did not have known follow-up outcomes at 18 to 26 months. Main Outcomes and Measures: Rates of mortality, major morbidities, and care practice use over time were evaluated using models adjusted for baseline characteristics, center, and birth year. Data analyses were conducted from 2018 to 2019. Results: In total, 20 092 infants with a mean (SD) gestational age of 25.1 (1.5) weeks met the inclusion criteria and were available for the primary outcome: 8331 (41.5%) black infants, 3701 (18.4%) Hispanic infants, and 8060 (40.1%) white infants. Hospital mortality decreased over time in all groups. The rate of improvement in hospital mortality over time did not differ among black and Hispanic infants compared with white infants (black infants went from 35% to 24%, Hispanic infants went from 32% to 27%, and white infants went from 30% to 22%; P = .59 for race × year interaction). The rates of late-onset sepsis among black infants (went from 37% to 24%) and Hispanic infants (went from 45% to 23%) were initially higher than for white infants (went from 36% to 25%) but decreased more rapidly and converged during the most recent years (P = .02 for race × year interaction). Changes in rates of other major morbidities did not differ by race/ethnicity. Death before follow-up decreased over time (from 2006 to 2014: black infants, 14%; Hispanic infants, 39%, white infants, 15%), but moderate-severe neurodevelopmental impairment increased over time in all racial/ethnic groups (increase from 2006 to 2014: black infants, 70%; Hispanic infants, 123%; white infants, 130%). Rates of antenatal corticosteroid exposure (black infants went from 72% to 90%, Hispanic infants went from 73% to 83%, and white infants went from 86% to 90%; P = .01 for race × year interaction) and of cesarean delivery (black infants went from 45% to 59%, Hispanic infants went from 49% to 59%, and white infants went from 62% to 63%; P = .03 for race × year interaction) were initially lower among black and Hispanic infants compared with white infants, but these differences decreased over time. Conclusions and Relevance: Among extremely preterm infants, improvements in adjusted rates of mortality and most major morbidities did not differ by race/ethnicity, but rates of neurodevelopmental impairment increased in all groups. There were narrowing racial/ethnic disparities in important care practices, including the use of antenatal corticosteroids and cesarean delivery.


Asunto(s)
Corticoesteroides/efectos adversos , Disparidades en Atención de Salud/etnología , Mortalidad Hospitalaria/tendencias , Trastornos del Neurodesarrollo/etnología , Peso al Nacer , Estudios de Casos y Controles , Cesárea/estadística & datos numéricos , Salud Infantil/etnología , Salud Infantil/tendencias , Estudios de Cohortes , Etnicidad , Femenino , Edad Gestacional , Humanos , Recien Nacido Extremadamente Prematuro , Recién Nacido , Morbilidad/tendencias , Trastornos del Neurodesarrollo/epidemiología , Embarazo , Atención Prenatal , Estudios Prospectivos , Estados Unidos/etnología
2.
Arch Dis Child Fetal Neonatal Ed ; 105(2): 138-144, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31229956

RESUMEN

OBJECTIVE: To identify achieved oxygen saturations (SpO2) associated with increased risk of severe retinopathy of prematurity (ROP). DESIGN: This is a secondary analysis of the Surfactant Positive Airway Pressure and Pulse Oximetry Trial (SUPPORT)randomised controlled trial. SpO2 was recorded up to 36 weeks' postmenstrual age. Saturations through 9 postnatal weeks were explored graphically, and logistic regression models were created to predict severe ROP. SETTING: 20 centres of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. PATIENTS: 984 surviving infants of 24-27 weeks' gestational age born in 2005-2009. INTERVENTIONS: SUPPORT targeted SpO2 to a lower (85%-89%) or higher (91%-95%) range through 36 weeks' postmenstrual age or off respiratory support. MAIN OUTCOME MEASURES: Severe ROP defined as threshold ROP, ophthalmological surgery or bevacizumab treatment. RESULTS: There were statistically significant interactions between duration of oxygen supplementation and percentage of time in certain achieved saturation ranges. Specifically, for infants who spent at least 2 weeks on oxygen in postnatal weeks 1-5, a higher percentage of time at 91%-96% SpO2 was associated with increased odds of severe ROP. For infants who spent at least 3 weeks on oxygen in postnatal weeks 6-9, a higher percentage of time at 97%-100% SpO2 was associated with increased odds of severe ROP. Other significant risk factors were lower gestational age and birth weight, non-Hispanic white versus black race, prospectively defined severe illness, late-onset sepsis or meningitis, and clinical centre. CONCLUSIONS: Among extremely preterm survivors to discharge, the association between SpO2 and severe ROP depended on the timing and duration of oxygen supplementation.


Asunto(s)
Recien Nacido Extremadamente Prematuro , Terapia por Inhalación de Oxígeno/efectos adversos , Terapia por Inhalación de Oxígeno/métodos , Oxígeno/sangre , Retinopatía de la Prematuridad/epidemiología , Retinopatía de la Prematuridad/terapia , Peso al Nacer , Relación Dosis-Respuesta a Droga , Femenino , Edad Gestacional , Humanos , Recién Nacido , Modelos Logísticos , Masculino , Oximetría , Retinopatía de la Prematuridad/sangre , Factores de Riesgo , Índice de Severidad de la Enfermedad
3.
J Pediatr ; 204: 96-102.e4, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30337189

RESUMEN

OBJECTIVE: To assess whether length of hospital stay is decreased among moderately preterm infants weaned from incubator to crib at a lower vs higher weight. STUDY DESIGN: This trial was conducted in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. Infants with gestational ages 29-33 weeks, birthweight <1600 g, and in an incubator were randomly assigned to a weaning weight of 1600 or 1800 g. Within 60 to 100 g of weaning weight, the incubator temperature was decreased by 1.0°C to 1.5°C every 24 hours until 28.0°C. The infants were weaned to the crib following stable temperature at 36.5°C to 37.4°C for 8 to 12 hours. Clothing and bedcoverings were standardized. The primary outcome was length of hospital stay from birth to discharge; secondary outcomes included length of stay and growth velocity from weaning to discharge. Adverse events were monitored. RESULTS: Of 1565 infants screened, 885 were eligible, and 366 enrolled-187 to the 1600-g and 179 to the 1800-g group. Maternal and neonatal characteristics did not differ among weight groups. Length of hospital stay was a median of 43 days in the lower and 41 days in the higher weight group (P = .12). Growth velocity from completion of weaning to discharge was higher in the lower weight group, 13.7 g/kg/day vs 12.8 g/kg/day (P = .005). Groups did not differ in adverse events. CONCLUSIONS: Among moderately preterm neonates, weaning from incubator to crib at a lower weight did not decrease length of stay, but was safe and was accompanied by higher weight gain after weaning. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02160002.


Asunto(s)
Incubadoras para Lactantes/estadística & datos numéricos , Equipo Infantil/estadística & datos numéricos , Tiempo de Internación/estadística & datos numéricos , Alta del Paciente/estadística & datos numéricos , Peso Corporal , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro/fisiología , Unidades de Cuidado Intensivo Neonatal/estadística & datos numéricos , Masculino
4.
Am J Obstet Gynecol ; 218(1): 130.e1-130.e13, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29138031

RESUMEN

BACKGROUND: Antenatal corticosteroids are given primarily to induce fetal lung maturation but results from meta-analyses of randomized controlled trials have not shown mortality or pulmonary benefits for extremely preterm infants although these are the infants most at risk of mortality and pulmonary disease. OBJECTIVE: We sought to determine if exposure to antenatal corticosteroids is associated with a lower rate of death and pulmonary morbidities by 36 weeks' postmenstrual age. STUDY DESIGN: Prospectively collected data on 11,022 infants 22 0/7 to 28 6/7 weeks' gestational age with a birthweight of ≥401 g born from Jan. 1, 2006, through Dec. 31, 2014, were analyzed. The rate of death and the rate of physiologic bronchopulmonary dysplasia by 36 weeks' postmenstrual age were analyzed by level of exposure to antenatal corticosteroids using models adjusted for maternal variables, infant variables, center, and epoch. RESULTS: Infants exposed to any antenatal corticosteroids had a lower rate of death (2193/9670 [22.7%]) compared to infants without exposure (540/1302 [41.5%]) (adjusted relative risk, 0.71; 95% confidence interval, 0.65-0.76; P < .0001). Infants exposed to a partial course of antenatal corticosteroids also had a lower rate of death (654/2520 [26.0%]) compared to infants without exposure (540/1302 [41.5%]); (adjusted relative risk, 0.77; 95% confidence interval, 0.70-0.85; P < .0001). In an analysis by each week of gestation, infants exposed to a complete course of antenatal corticosteroids had lower mortality before discharge compared to infants without exposure at each week from 23-27 weeks' gestation and infants exposed to a partial course of antenatal corticosteroids had lower mortality at 23, 24, and 26 weeks' gestation. Rates of bronchopulmonary dysplasia in survivors did not differ by antenatal corticosteroid exposure. The rate of death due to respiratory distress syndrome, the rate of surfactant use, and the rate of mechanical ventilation were lower in infants exposed to any antenatal corticosteroids compared to infants without exposure. CONCLUSION: Among infants 22-28 weeks' gestational age, any or partial antenatal exposure to corticosteroids compared to no exposure is associated with a lower rate of death while the rate of bronchopulmonary dysplasia in survivors did not differ.


Asunto(s)
Glucocorticoides/uso terapéutico , Recien Nacido Extremadamente Prematuro , Efectos Tardíos de la Exposición Prenatal , Displasia Broncopulmonar/epidemiología , Utilización de Medicamentos , Femenino , Edad Gestacional , Humanos , Lactante , Mortalidad Infantil , Recien Nacido con Peso al Nacer Extremadamente Bajo , Recién Nacido , Masculino , Embarazo , Estudios Prospectivos , Surfactantes Pulmonares/uso terapéutico , Respiración Artificial/estadística & datos numéricos , Síndrome de Dificultad Respiratoria del Recién Nacido/mortalidad , Estados Unidos/epidemiología
5.
Pediatr Infect Dis J ; 36(8): 774-779, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28709162

RESUMEN

BACKGROUND: Late-onset sepsis (LOS) is an important cause of death and neurodevelopmental impairment in premature infants. The purpose of this study was to assess overall incidence of LOS, distribution of LOS-causative organisms and center variation in incidence of LOS for extremely premature infants over time. METHODS: In a retrospective analysis of infants 401-1000 g birth weight and 22-28 6/7 weeks of gestational age born at 12 National Institute of Child Health and Human Development Neonatal Research Network centers in the years 2000-2005 (era 1) or 2006-2011 (era 2) who survived >72 hours, we compared the incidence of LOS and pathogen distribution in the 2 eras using the χ test. We also examined the effect of birth year on the incidence of LOS using multivariable regression to adjust for nonmodifiable risk factors and for center. To assess whether the incidence of LOS was different among centers in era 2, we used a multivariable regression model to adjust for nonmodifiable risk factors. RESULTS: Ten-thousand one-hundred thirty-one infants were studied. LOS occurred in 2083 of 5031 (41%) infants in era 1 and 1728 of 5100 (34%) infants in era 2 (P < 0.001). Birth year was a significant predictor of LOS on adjusted analysis, with birth years 2000-2009 having a significantly higher odds of LOS than the reference year 2011. Pathogens did not differ, with the exception of decreased fungal infection (P < 0.001). In era 2, 9 centers had significantly higher odds of LOS compared with the center with the lowest incidence. CONCLUSIONS: The incidence of LOS decreased over time. Further investigation is warranted to determine which interventions have the greatest impact on infection rates.


Asunto(s)
Recien Nacido Extremadamente Prematuro , Sepsis Neonatal/epidemiología , Femenino , Humanos , Recién Nacido , Masculino , Estudios Retrospectivos , Estados Unidos/epidemiología
6.
Pediatr Res ; 82(2): 297-304, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28419085

RESUMEN

BackgroundExtremely preterm infants (EPT, <29 weeks' gestation) represent only 0.9% of births in the United States; yet these infants are the focus of most published research. Moderately preterm neonates (MPT, 29-336/7 weeks) are an understudied group of high-risk infants.MethodsTo determine the neonatal outcomes of MPT infants across the gestational age spectrum, and to compare these with EPT infants. A prospective observational cohort was formed in 18 level 3-4 neonatal intensive care units (NICUs) in the Eunice Kennedy Shriver NICHD Neonatal Research Network. Participants included all MPT infants admitted to NICUs and all EPT infants born at sites between January 2012 and November 2013. Antenatal characteristics and neonatal morbidities were abstracted from records using pre-specified definitions by trained neonatal research nurses.ResultsMPT infants experienced morbidities similar to, although at lower rates than, those of EPT infants. The main cause of mortality was congenital malformation, accounting for 43% of deaths. Central Nervous System injury occurred, including intraventricular hemorrhage. Most MPT infants required respiratory support, but sequelae such as bronchopulmonary dysplasia were rare. The primary contributors to hospitalization beyond 36 weeks' gestation were inability to achieve adequate oral intake and persistent apnea.ConclusionsMPT infants experience morbidity and prolonged hospitalization. Such morbidity deserves focused research to improve therapeutic and prevention strategies.


Asunto(s)
Recien Nacido Prematuro , Adulto , Femenino , Humanos , Lactante , Mortalidad Infantil , Recién Nacido , Embarazo , Estudios Prospectivos , Sistema de Registros , Resultado del Tratamiento , Estados Unidos/epidemiología , Adulto Joven
7.
J Pediatr ; 176: 62-68.e4, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27344218

RESUMEN

OBJECTIVE: To test whether infants randomized to a lower oxygen saturation (peripheral capillary oxygen saturation [SpO2]) target range while on supplemental oxygen from birth will have better growth velocity from birth to 36 weeks postmenstrual age (PMA) and less growth failure at 36 weeks PMA and 18-22 months corrected age. STUDY DESIGN: We evaluated a subgroup of 810 preterm infants from the Surfactant, Positive Pressure, and Oxygenation Randomized Trial, randomized at birth to lower (85%-89%, n = 402, PMA 26 ± 1 weeks, birth weight 839 ± 186 g) or higher (91%-95%, n = 408, PMA 26 ± 1 weeks, birth weight 840 ± 191 g) SpO2 target ranges. Anthropometric measures were obtained at birth, postnatal days 7, 14, 21, and 28; then at 32 and 36 weeks PMA; and 18-22 months corrected age. Growth velocities were estimated with the exponential method and analyzed with linear mixed models. Poor growth outcome, defined as weight <10th percentile at 36 weeks PMA and 18-22 months corrected age, was compared across the 2 treatment groups by the use of robust Poisson regression. RESULTS: Growth outcomes including growth at 36 weeks PMA and 18-22 months corrected age, as well as growth velocity were similar in the lower and higher SpO2 target groups. CONCLUSION: Targeting different oxygen saturation ranges between 85% and 95% from birth did not impact growth velocity or reduce growth failure in preterm infants.


Asunto(s)
Crecimiento , Oximetría , Oxígeno/metabolismo , Respiración Artificial , Femenino , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Masculino , Oxígeno/administración & dosificación
8.
Arch Dis Child Fetal Neonatal Ed ; 101(3): F201-6, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26567120

RESUMEN

OBJECTIVE: To investigate the relationships between early blood pressure (BP) changes, receipt of antihypotensive therapy and 18-22 months' corrected age (CA) outcomes for extremely preterm infants. DESIGN: Prospective observational study of infants 23(0/7)-26(6/7) weeks' gestational age (GA). Hourly BP values and antihypotensive therapy exposure in the first 24 h were recorded. Four groups were defined: infants who did or did not receive antihypotensive therapy in whom BP did or did not rise at the expected rate (defined as an increase in the mean arterial BP of ≥5 mm Hg/day). Random-intercept logistic modelling controlling for centre clustering, GA and illness severity was used to investigate the relationship between BP, antihypotensive therapies and infant outcomes. SETTING: Sixteen academic centres of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. MAIN OUTCOME MEASURES: Death or neurodevelopmental impairment/developmental delay (NIDD) at 18-22 months' CA. RESULTS: Of 367 infants, 203 (55%) received an antihypotensive therapy, 272 (74%) survived to discharge and 331 (90%) had a known outcome at 18-22 months' CA. With logistic regression, there was an increased risk of death/NIDD with antihypotensive therapy versus no treatment (OR 1.836, 95% CI 1.092 to 3.086), but not NIDD alone (OR 1.53, 95% CI 0.708 to 3.307). CONCLUSIONS: Independent of early BP changes, antihypotensive therapy exposure was associated with an increased risk of death/NIDD at 18-22 months' CA when controlling for risk factors known to affect survival and neurodevelopment. CLINICAL TRIAL REGISTRATION NUMBER: clinicaltrials.gov #NCT00874393.


Asunto(s)
Presión Sanguínea , Discapacidades del Desarrollo/epidemiología , Hipotensión/tratamiento farmacológico , Mortalidad Infantil , Recien Nacido Extremadamente Prematuro , Centros Médicos Académicos , Cardiotónicos/uso terapéutico , Soluciones Cristaloides , Dobutamina/uso terapéutico , Dopamina/uso terapéutico , Epinefrina/uso terapéutico , Estudios de Seguimiento , Edad Gestacional , Humanos , Hidrocortisona/uso terapéutico , Lactante , Recién Nacido , Soluciones Isotónicas/uso terapéutico , Modelos Logísticos , Estudios Prospectivos , Simpatomiméticos/uso terapéutico , Estados Unidos/epidemiología
9.
JAMA ; 314(10): 1039-51, 2015 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-26348753

RESUMEN

IMPORTANCE: Extremely preterm infants contribute disproportionately to neonatal morbidity and mortality. OBJECTIVE: To review 20-year trends in maternal/neonatal care, complications, and mortality among extremely preterm infants born at Neonatal Research Network centers. DESIGN, SETTING, PARTICIPANTS: Prospective registry of 34,636 infants, 22 to 28 weeks' gestation, birth weight of 401 to 1500 g, and born at 26 network centers between 1993 and 2012. EXPOSURES: Extremely preterm birth. MAIN OUTCOMES AND MEASURES: Maternal/neonatal care, morbidities, and survival. Major morbidities, reported for infants who survived more than 12 hours, were severe necrotizing enterocolitis, infection, bronchopulmonary dysplasia, severe intracranial hemorrhage, cystic periventricular leukomalacia, and/or severe retinopathy of prematurity. Regression models assessed yearly changes and were adjusted for study center, race/ethnicity, gestational age, birth weight for gestational age, and sex. RESULTS: Use of antenatal corticosteroids increased from 1993 to 2012 (24% [348 of 1431 infants]) to 87% (1674 of 1919 infants]; P < .001), as did cesarean delivery (44% [625 of 1431 births] to 64% [1227 of 1921]; P < .001). Delivery room intubation decreased from 80% (1144 of 1433 infants) in 1993 to 65% (1253 of 1922) in 2012 (P < .001). After increasing in the 1990s, postnatal steroid use declined to 8% (141 of 1757 infants) in 2004 (P < .001), with no significant change thereafter. Although most infants were ventilated, continuous positive airway pressure without ventilation increased from 7% (120 of 1666 infants) in 2002 to 11% (190 of 1756 infants) in 2012 (P < .001). Despite no improvement from 1993 to 2004, rates of late-onset sepsis declined between 2005 and 2012 for infants of each gestational age (median, 26 weeks [37% {109 of 296} to 27% {85 of 320}]; adjusted relative risk [RR], 0.93 [95% CI, 0.92-0.94]). Rates of other morbidities declined, but bronchopulmonary dysplasia increased between 2009 and 2012 for infants at 26 to 27 weeks' gestation (26 weeks, 50% [130 of 258] to 55% [164 of 297]; P < .001). Survival increased between 2009 and 2012 for infants at 23 weeks' gestation (27% [41 of 152] to 33% [50 of 150]; adjusted RR, 1.09 [95% CI, 1.05-1.14]) and 24 weeks (63% [156 of 248] to 65% [174 of 269]; adjusted RR, 1.05 [95% CI, 1.03-1.07]), with smaller relative increases for infants at 25 and 27 weeks' gestation, and no change for infants at 22, 26, and 28 weeks' gestation. Survival without major morbidity increased approximately 2% per year for infants at 25 to 28 weeks' gestation, with no change for infants at 22 to 24 weeks' gestation. CONCLUSIONS AND RELEVANCE: Among extremely preterm infants born at US academic centers over the last 20 years, changes in maternal and infant care practices and modest reductions in several morbidities were observed, although bronchopulmonary dysplasia increased. Survival increased most markedly for infants born at 23 and 24 weeks' gestation and survival without major morbidity increased for infants aged 25 to 28 weeks. These findings may be valuable in counseling families and developing novel interventions. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00063063.


Asunto(s)
Corticoesteroides/uso terapéutico , Recien Nacido Extremadamente Prematuro , Enfermedades del Prematuro/epidemiología , Adulto , Displasia Broncopulmonar/epidemiología , Cesárea/estadística & datos numéricos , Cesárea/tendencias , Presión de las Vías Aéreas Positiva Contínua/estadística & datos numéricos , Presión de las Vías Aéreas Positiva Contínua/tendencias , Enterocolitis Necrotizante/epidemiología , Femenino , Edad Gestacional , Humanos , Recién Nacido , Recien Nacido Prematuro , Enfermedades del Prematuro/mortalidad , Enfermedades del Prematuro/terapia , Infecciones/epidemiología , Cuidado Intensivo Neonatal/estadística & datos numéricos , Hemorragias Intracraneales/epidemiología , Leucomalacia Periventricular/epidemiología , Masculino , Embarazo , Retinopatía de la Prematuridad/epidemiología , Análisis de Supervivencia , Estados Unidos/epidemiología
10.
Pediatrics ; 135(1): e32-42, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25554820

RESUMEN

BACKGROUND: Extremely preterm infants are at risk for neurodevelopmental impairment (NDI). Early cranial ultrasound (CUS) is usual practice, but near-term brain MRI has been reported to better predict outcomes. We prospectively evaluated MRI white matter abnormality (WMA) and cerebellar lesions, and serial CUS adverse findings as predictors of outcomes at 18 to 22 months' corrected age. METHODS: Early and late CUS, and brain MRI were read by masked central readers, in a large cohort (n = 480) of infants <28 weeks' gestation surviving to near term in the Neonatal Research Network. Outcomes included NDI or death after neuroimaging, and significant gross motor impairment or death, with NDI defined as cognitive composite score <70, significant gross motor impairment, and severe hearing or visual impairment. Multivariable models evaluated the relative predictive value of neuroimaging while controlling for other factors. RESULTS: Of 480 infants, 15 died and 20 were lost. Increasing severity of WMA and significant cerebellar lesions on MRI were associated with adverse outcomes. Cerebellar lesions were rarely identified by CUS. In full multivariable models, both late CUS and MRI, but not early CUS, remained independently associated with NDI or death (MRI cerebellar lesions: odds ratio, 3.0 [95% confidence interval: 1.3-6.8]; late CUS: odds ratio, 9.8 [95% confidence interval: 2.8-35]), and significant gross motor impairment or death. In models that did not include late CUS, MRI moderate-severe WMA was independently associated with adverse outcomes. CONCLUSIONS: Both late CUS and near-term MRI abnormalities were associated with outcomes, independent of early CUS and other factors, underscoring the relative prognostic value of near-term neuroimaging.


Asunto(s)
Encéfalo/crecimiento & desarrollo , Discapacidades del Desarrollo/diagnóstico , Ecoencefalografía , Imagen por Resonancia Magnética , Neuroimagen , Femenino , Humanos , Lactante , Recien Nacido Extremadamente Prematuro , Recién Nacido , Masculino , Estudios Prospectivos
11.
N Engl J Med ; 372(4): 331-40, 2015 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-25607427

RESUMEN

BACKGROUND: Understanding the causes and timing of death in extremely premature infants may guide research efforts and inform the counseling of families. METHODS: We analyzed prospectively collected data on 6075 deaths among 22,248 live births, with gestational ages of 22 0/7 to 28 6/7 weeks, among infants born in study hospitals within the National Institute of Child Health and Human Development Neonatal Research Network. We compared overall and cause-specific in-hospital mortality across three periods from 2000 through 2011, with adjustment for baseline differences. RESULTS: The number of deaths per 1000 live births was 275 (95% confidence interval [CI], 264 to 285) from 2000 through 2003 and 285 (95% CI, 275 to 295) from 2004 through 2007; the number decreased to 258 (95% CI, 248 to 268) in the 2008-2011 period (P=0.003 for the comparison across three periods). There were fewer pulmonary-related deaths attributed to the respiratory distress syndrome and bronchopulmonary dysplasia in 2008-2011 than in 2000-2003 and 2004-2007 (68 [95% CI, 63 to 74] vs. 83 [95% CI, 77 to 90] and 84 [95% CI, 78 to 90] per 1000 live births, respectively; P=0.002). Similarly, in 2008-2011, as compared with 2000-2003, there were decreases in deaths attributed to immaturity (P=0.05) and deaths complicated by infection (P=0.04) or central nervous system injury (P<0.001); however, there were increases in deaths attributed to necrotizing enterocolitis (30 [95% CI, 27 to 34] vs. 23 [95% CI, 20 to 27], P=0.03). Overall, 40.4% of deaths occurred within 12 hours after birth, and 17.3% occurred after 28 days. CONCLUSIONS: We found that from 2000 through 2011, overall mortality declined among extremely premature infants. Deaths related to pulmonary causes, immaturity, infection, and central nervous system injury decreased, while necrotizing enterocolitis-related deaths increased. (Funded by the National Institutes of Health.).


Asunto(s)
Mortalidad Infantil/tendencias , Recien Nacido Extremadamente Prematuro , Enfermedades del Prematuro/mortalidad , Causas de Muerte , Anomalías Congénitas/mortalidad , Enterocolitis Necrotizante/mortalidad , Edad Gestacional , Humanos , Lactante , Recién Nacido , Recién Nacido de muy Bajo Peso , Factores de Riesgo , Estados Unidos/epidemiología
12.
Am J Obstet Gynecol ; 212(1): 94.e1-7, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25046806

RESUMEN

OBJECTIVE: Antenatal magnesium (anteMg) is used for various obstetric indications including fetal neuroprotection. Infants exposed to anteMg may be at risk for respiratory depression and delivery room (DR) resuscitation. The study objective was to compare the risk of acute cardiorespiratory events among preterm infants who were and were not exposed to anteMg. STUDY DESIGN: This was a retrospective analysis of prospective data collected in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network's Generic Database from April 1, 2011, through March 31, 2012. The primary outcome was DR intubation or respiratory support at birth or on day 1 of life. Secondary outcomes were invasive mechanical ventilation, hypotension treatment, neonatal morbidities, and mortality. Logistic regression analysis evaluated the risk of primary outcome after adjustment for covariates. RESULTS: We evaluated 1544 infants <29 weeks' gestational age (1091 in anteMg group and 453 in nonexposed group). Mothers in the anteMg group were more likely to have higher education, pregnancy-induced hypertension, and antenatal corticosteroids, while their infants were younger in gestation and weighed less (P < .05). The primary outcome (odds ratio [OR], 1.2; 95% confidence interval [CI], 0.88-1.65) was similar between groups. Hypotension treatment (OR, 0.70; 95% CI, 0.51-0.97) and invasive mechanical ventilation (OR, 0.54; 95% CI, 0.41-0.72) were significantly less in the anteMg group. CONCLUSION: Among preterm infants age <29 weeks' gestation, anteMg exposure was not associated with an increase in cardiorespiratory events in the early newborn period. The safety of anteMg as measured by the need for DR intubation or respiratory support on day 1 of life was comparable between groups.


Asunto(s)
Cardiopatías/inducido químicamente , Enfermedades del Prematuro/inducido químicamente , Sulfato de Magnesio/efectos adversos , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Trastornos Respiratorios/inducido químicamente , Enfermedad Aguda , Adulto , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Embarazo , Estudios Retrospectivos , Adulto Joven
13.
Pediatrics ; 134(5): e1369-77, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25349317

RESUMEN

OBJECTIVE: Prophylactic indomethacin reduces severe intraventricular hemorrhage but may increase spontaneous intestinal perforation (SIP) in extremely low birth weight (ELBW) infants. Early feedings improve nutritional outcomes but may increase the risk of SIP. Despite their benefits, use of these therapies varies largely by physician preferences in part because of the concern for SIP. METHODS: This was a cohort study of 15,751 ELBW infants in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network from 1999 to 2010 who survived beyond 12 hours after birth. The risk of SIP was compared between groups of infants with and without exposure to prophylactic indomethacin and early feeding in unadjusted analyses and in analyses adjusted for center and for risks of SIP. RESULTS: Among infants exposed to prophylactic indomethacin, the risk of SIP did not differ between the indomethacin/early-feeding group compared with the indomethacin/no-early-feeding group (adjusted relative risk [RR] 0.74, 95% confidence interval [CI] 0.49-1.11). The risk of SIP was lower in the indomethacin/early-feeding group compared with the no indomethacin/no-early-feeding group (adjusted RR 0.58, 95% CI 0.37-0.90, P = .0159). Among infants not exposed to indomethacin, early feeding was associated with a lower risk of SIP compared with the no early feeding group (adjusted RR 0.53, 95% CI 0.36-0.777, P = .0011). CONCLUSIONS: The combined or individual use of prophylactic indomethacin and early feeding was not associated with an increased risk of SIP in ELBW infants.


Asunto(s)
Indometacina/administración & dosificación , Recien Nacido con Peso al Nacer Extremadamente Bajo , Perforación Intestinal/diagnóstico , Perforación Intestinal/prevención & control , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Recien Nacido con Peso al Nacer Extremadamente Bajo/crecimiento & desarrollo , Recién Nacido , Masculino , Estudios Prospectivos , Estudios Retrospectivos
14.
JAMA Pediatr ; 168(8): 746-54, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24934607

RESUMEN

IMPORTANCE: Reduced death and neurodevelopmental impairment among infants is a goal of perinatal medicine. OBJECTIVE: To assess the association between surgery during the initial hospitalization and death or neurodevelopmental impairment of very low-birth-weight infants. DESIGN, SETTING, AND PARTICIPANTS: A retrospective cohort analysis was conducted of patients enrolled in the National Institute of Child Health and Human Development Neonatal Research Network Generic Database from 1998 through 2009 and evaluated at 18 to 22 months' corrected age. Twenty-two academic neonatal intensive care units participated. Inclusion criteria were birth weight 401 to 1500 g, survival to 12 hours, and availability for follow-up. A total of 12 111 infants were included in analyses. EXPOSURES: Surgical procedures; surgery also was classified by expected anesthesia type as major (general anesthesia) or minor (nongeneral anesthesia). MAIN OUTCOMES AND MEASURES: Multivariable logistic regression analyses planned a priori were performed for the primary outcome of death or neurodevelopmental impairment and for the secondary outcome of neurodevelopmental impairment among survivors. Multivariable linear regression analyses were performed as planned for the adjusted mean scores of the Mental Developmental Index and Psychomotor Developmental Index of the Bayley Scales of Infant Development, Second Edition, for patients born before 2006. RESULTS: A total of 2186 infants underwent major surgery, 784 had minor surgery, and 9141 infants did not undergo surgery. The risk-adjusted odds ratio of death or neurodevelopmental impairment for all surgery patients compared with those who had no surgery was 1.29 (95% CI, 1.08-1.55). For patients who had major surgery compared with those who had no surgery, the risk-adjusted odds ratio of death or neurodevelopmental impairment was 1.52 (95% CI, 1.24-1.87). Patients classified as having minor surgery had no increased adjusted risk. Among survivors who had major surgery compared with those who had no surgery, the adjusted risk of neurodevelopmental impairment was greater and the adjusted mean Bayley scores were lower. CONCLUSIONS AND RELEVANCE: Major surgery in very low-birth-weight infants is independently associated with a greater than 50% increased risk of death or neurodevelopmental impairment and of neurodevelopmental impairment at 18 to 22 months' corrected age. The role of general anesthesia is implicated but remains unproven.


Asunto(s)
Discapacidades del Desarrollo/epidemiología , Enfermedades del Recién Nacido/cirugía , Recién Nacido de muy Bajo Peso , Enfermedades del Sistema Nervioso/epidemiología , Anestesia/métodos , Femenino , Humanos , Recién Nacido , Enfermedades del Recién Nacido/mortalidad , Masculino , Estudios Retrospectivos , Factores de Riesgo , Estados Unidos/epidemiología
15.
J Pediatr ; 165(2): 240-249.e4, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24725582

RESUMEN

OBJECTIVE: To explore the early childhood pulmonary outcomes of infants who participated in the National Institute of Child Health and Human Development's Surfactant Positive Airway Pressure and Pulse Oximetry Randomized Trial (SUPPORT), using a factorial design that randomized extremely preterm infants to lower vs higher oxygen saturation targets and delivery room continuous positive airway pressure (CPAP) vs intubation/surfactant. STUDY DESIGN: The Breathing Outcomes Study, a prospective secondary study to the Surfactant Positive Airway Pressure and Pulse Oximetry Randomized Trial, assessed respiratory morbidity at 6-month intervals from hospital discharge to 18-22 months corrected age (CA). Two prespecified primary outcomes-wheezing more than twice per week during the worst 2-week period and cough longer than 3 days without a cold-were compared for each randomized intervention. RESULTS: One or more interviews were completed for 918 of the 922 eligible infants. The incidences of wheezing and cough were 47.9% and 31.0%, respectively, and did not differ between the study arms of either randomized intervention. Infants randomized to lower vs higher oxygen saturation targets had a similar risk of death or respiratory morbidity (except for croup and treatment with oxygen or diuretics at home). Infants randomized to CPAP vs intubation/surfactant had fewer episodes of wheezing without a cold (28.9% vs 36.5%; P<.05), respiratory illnesses diagnosed by a doctor (47.7% vs 55.2%; P<.05), and physician or emergency room visits for breathing problems (68.0% vs 72.9%; P<.05) by 18-22 months CA. CONCLUSION: Treatment with early CPAP rather than intubation/surfactant is associated with less respiratory morbidity by 18-22 months CA. Longitudinal assessment of pulmonary morbidity is necessary to fully evaluate the potential benefits of respiratory interventions for neonates.


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua/métodos , Oximetría/métodos , Oxígeno/uso terapéutico , Surfactantes Pulmonares/uso terapéutico , Síndrome de Dificultad Respiratoria del Recién Nacido/terapia , Salas de Parto , Femenino , Humanos , Lactante , Recien Nacido Extremadamente Prematuro , Recién Nacido , Recien Nacido Prematuro , Masculino , Estudios Prospectivos , Encuestas y Cuestionarios , Resultado del Tratamiento , Estados Unidos
16.
JAMA Pediatr ; 168(2): 137-47, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24378638

RESUMEN

IMPORTANCE: Chorioamnionitis is strongly linked to preterm birth and neonatal infection. The association between histological and clinical chorioamnionitis and cognitive, behavioral, and neurodevelopmental outcomes among extremely preterm neonates is less clear. We evaluated the impact of chorioamnionitis on 18- to 22-month neurodevelopmental outcomes in a contemporary cohort of extremely preterm neonates. OBJECTIVE: To compare the neonatal and neurodevelopmental outcomes of 3 groups of extremely low-gestational-age infants with increasing exposure to perinatal inflammation: no chorioamnionitis, histological chorioamnionitis alone, or histological plus clinical chorioamnionitis. DESIGN, SETTING, AND PARTICIPANTS: Longitudinal observational study at 16 centers of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network. Two thousand three hundred ninety extremely preterm infants born at less than 27 weeks' gestational age (GA) between January 1, 2006, and December 31, 2008, with placental histopathology and 18 to 22 months' corrected age follow-up data were eligible. MAIN EXPOSURE: Chorioamnionitis. MAIN OUTCOMES AND MEASURES: Outcomes included cerebral palsy, gross motor functional limitation, behavioral scores (according to the Brief Infant-Toddler Social and Emotional Assessment), cognitive and language scores (according to the Bayley Scales of Infant and Toddler Development, Third Edition), and composite measures of death/neurodevelopmental impairment. Multivariable logistic and linear regression models were developed to assess the association between chorioamnionitis and outcomes while controlling for important variables known at birth. RESULTS: Neonates exposed to chorioamnionitis had a lower GA and higher rates of early-onset sepsis and severe periventricular-intraventricular hemorrhage as compared with unexposed neonates. In multivariable models evaluating death and neurodevelopmental outcomes, inclusion of GA in the model diminished the association between chorioamnionitis and adverse outcomes. Still, histological plus clinical chorioamnionitis was associated with increased risk of cognitive impairment as compared with no chorioamnionitis (adjusted odds ratio [OR], 2.38 [95% CI, 1.32 to 4.28] without GA; adjusted OR, 2.00 [95% CI, 1.10 to 3.64] with GA as a covariate). Histological chorioamnionitis alone was associated with lower odds of death/neurodevelopmental impairment as compared with histological plus clinical chorioamnionitis (adjusted OR, 0.68 [95% CI, 0.52 to 0.89] without GA; adjusted OR, 0.66 [95% CI, 0.49 to 0.89] with GA as a covariate). Risk of behavioral problems did not differ statistically between groups. CONCLUSIONS AND RELEVANCE: Antenatal exposure to chorioamnionitis is associated with altered odds of cognitive impairment and death/neurodevelopmental impairment in extremely preterm infants.


Asunto(s)
Corioamnionitis/epidemiología , Recien Nacido Extremadamente Prematuro , Enfermedades del Prematuro/epidemiología , Parálisis Cerebral/epidemiología , Trastornos de la Conducta Infantil/epidemiología , Trastornos del Conocimiento/epidemiología , Discapacidades del Desarrollo/epidemiología , Femenino , Edad Gestacional , Humanos , Lactante , Modelos Lineales , Modelos Logísticos , Estudios Longitudinales , Masculino , Embarazo , Factores de Riesgo , Estados Unidos/epidemiología
17.
Pediatrics ; 133(2): 226-35, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24446439

RESUMEN

OBJECTIVE: Little is known about how very low birth weight (VLBW) affects survival and morbidities among infants with trisomy 13 (T13) or trisomy 18 (T18). We examined the care plans for VLBW infants with T13 or T18 and compared their risks of mortality and neonatal morbidities with VLBW infants with trisomy 21 and VLBW infants without birth defects. METHODS: Infants with birth weight 401 to 1500 g born or cared for at a participating center of the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network during the period 1994-2009 were studied. Poisson regression models were used to examine risk of death and neonatal morbidities among infants with T13 or T18. RESULTS: Of 52,262 VLBW infants, 38 (0.07%) had T13 and 128 (0.24%) had T18. Intensity of care in the delivery room varied depending on whether the trisomy was diagnosed before or after birth. The plan for subsequent care for the majority of the infants was to withdraw care or to provide comfort care. Eleven percent of infants with T13 and 9% of infants with T18 survived to hospital discharge. Survivors with T13 or T18 had significantly increased risk of patent ductus arteriosus and respiratory distress syndrome compared with infants without birth defects. No infant with T13 or T18 developed necrotizing enterocolitis. CONCLUSIONS: In this cohort of liveborn VLBW infants with T13 or T18, the timing of trisomy diagnosis affected the plan for care, survival was poor, and death usually occurred early.


Asunto(s)
Trastornos de los Cromosomas/complicaciones , Trastornos de los Cromosomas/mortalidad , Síndrome de Down/complicaciones , Síndrome de Down/mortalidad , Recién Nacido de muy Bajo Peso , Trisomía , Cromosomas Humanos Par 13 , Cromosomas Humanos Par 18 , Femenino , Humanos , Recién Nacido , Masculino , Estudios Retrospectivos , Síndrome de la Trisomía 13 , Síndrome de la Trisomía 18
18.
Pediatrics ; 132(1): e175-84, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23753096

RESUMEN

OBJECTIVE: To examine factors affecting center differences in mortality for extremely low birth weight (ELBW) infants. METHODS: We analyzed data for 5418 ELBW infants born at 16 Neonatal Research Network centers during 2006-2009. The primary outcomes of early mortality (≤12 hours after birth) and in-hospital mortality were assessed by using multilevel hierarchical models. Models were developed to investigate associations of center rates of selected interventions with mortality while adjusting for patient-level risk factors. These analyses were performed for all gestational ages (GAs) and separately for GAs <25 weeks and ≥25 weeks. RESULTS: Early and in-hospital mortality rates among centers were 5% to 36% and 11% to 53% for all GAs, 13% to 73% and 28% to 90% for GAs <25 weeks, and 1% to 11% and 7% to 26% for GAs ≥25 weeks, respectively. Center intervention rates significantly predicted both early and in-hospital mortality for infants <25 weeks. For infants ≥25 weeks, intervention rates did not predict mortality. The variance in mortality among centers was significant for all GAs and outcomes. Center use of interventions and patient risk factors explained some but not all of the center variation in mortality rates. CONCLUSIONS: Center intervention rates explain a portion of the center variation in mortality, especially for infants born at <25 weeks' GA. This finding suggests that deaths may be prevented by standardizing care for very early GA infants. However, differences in patient characteristics and center intervention rates do not account for all of the observed variability in mortality; and for infants with GA ≥25 weeks these differences account for only a small part of the variation in mortality.


Asunto(s)
Mortalidad Hospitalaria , Hospitales Universitarios/estadística & datos numéricos , Recien Nacido con Peso al Nacer Extremadamente Bajo , Enfermedades del Prematuro/mortalidad , Unidades de Cuidado Intensivo Neonatal/estadística & datos numéricos , Causas de Muerte , Femenino , Edad Gestacional , Humanos , Recién Nacido , Enfermedades del Prematuro/terapia , Masculino , Pautas de la Práctica en Medicina/estadística & datos numéricos , Sistema de Registros/estadística & datos numéricos , Factores de Riesgo , Estados Unidos
19.
Pediatrics ; 132(1): 49-61, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23733791

RESUMEN

OBJECTIVE: Birth defects (BDs) are an important cause of infant mortality and disproportionately occur among low birth weight infants. We determined the prevalence of BDs in a cohort of very low birth weight (VLBW) infants cared for at the Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network (NRN) centers over a 10-year period and examined the relationship between anomalies, neonatal outcomes, and surgical care. METHODS: Infant and maternal data were collected prospectively for infants weighing 401 to 1500 g at NRN sites between January 1, 1998, and December 31, 2007. Poisson regression models were used to compare risk of outcomes for infants with versus without BDs while adjusting for gestational age and other characteristics. RESULTS: A BD was present in 1776 (4.8%) of the 37 262 infants in our VLBW cohort. Yearly prevalence of BDs increased from 4.0% of infants born in 1998 to 5.6% in 2007, P < .001. Mean gestational age overall was 28 weeks, and mean birth weight was 1007 g. Infants with BDs were more mature but more likely to be small for gestational age compared with infants without BDs. Chromosomal and cardiovascular anomalies were most frequent with each occurring in 20% of affected infants. Mortality was higher among infants with BDs (49% vs 18%; adjusted relative risk: 3.66 [95% confidence interval: 3.41-3.92]; P < .001) and varied by diagnosis. Among those surviving >3 days, more infants with BDs underwent major surgery (48% vs 13%, P < .001). CONCLUSIONS: Prevalence of BDs increased during the 10 years studied. BDs remain an important cause of neonatal morbidity and mortality among VLBW infants.


Asunto(s)
Anomalías Congénitas/diagnóstico , Anomalías Congénitas/mortalidad , Recién Nacido de muy Bajo Peso , Adulto , Peso al Nacer , Causas de Muerte , Aberraciones Cromosómicas , Estudios de Cohortes , Anomalías Congénitas/genética , Anomalías Congénitas/cirugía , Estudios Transversales , Femenino , Edad Gestacional , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/genética , Cardiopatías Congénitas/mortalidad , Cardiopatías Congénitas/cirugía , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Masculino , Edad Materna , National Institute of Child Health and Human Development (U.S.) , Distribución de Poisson , Sistema de Registros , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento , Estados Unidos
20.
Pediatrics ; 131(6): e1865-73, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23650301

RESUMEN

OBJECTIVE: To investigate the relationships among blood pressure (BP) values, antihypotensive therapies, and in-hospital outcomes to identify a BP threshold below which antihypotensive therapies may be beneficial. METHODS: Prospective observational study of infants 23(0/7) to 26(6/7) weeks' gestational age. Hourly BP values and antihypotensive therapy use in the first 24 hours were recorded. Low BP was investigated by using 15 definitions. Outcomes were examined by using regression analysis controlling for gestational age, the number of low BP values, and illness severity. RESULTS: Of 367 infants enrolled, 203 (55%) received at least 1 antihypotensive therapy. Treated infants were more likely to have low BP by any definition (P < .001), but for the 15 definitions of low BP investigated, therapy was not prescribed to 3% to 49% of infants with low BP and, paradoxically, was administered to 28% to 41% of infants without low BP. Treated infants were more likely than untreated infants to develop severe retinopathy of prematurity (15% vs 8%, P = .03) or severe intraventricular hemorrhage (22% vs 11%, P < .01) and less likely to survive (67% vs 78%, P = .02). However, with regression analysis, there were no significant differences between groups in survival or in-hospital morbidity rates. CONCLUSIONS: Factors other than BP contributed to the decision to use antihypotensive therapies. Infant outcomes were not improved with antihypotensive therapy for any of the 15 definitions of low BP investigated.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Utilización de Medicamentos/estadística & datos numéricos , Hipotensión/tratamiento farmacológico , Enfermedades del Prematuro/tratamiento farmacológico , Femenino , Humanos , Hipotensión/complicaciones , Recien Nacido Extremadamente Prematuro , Recién Nacido , Masculino , Estudios Prospectivos , Análisis de Regresión , Resultado del Tratamiento
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