Research Achievements - Original paper -
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Takeshi Arimitsu, Rika Fukutomi, Mayuko Kumagai, Hayato Shibuma, Yoko Yamanishi, Kei-Ichi Takahashi, Hirotaka Gima, Yoshitaka Seto, Hiroyuki Adachi, Hirokazu Arai, Masakatsu Higuchi, Shohei Ohgi, Hidenobu Ohta
Frontiers in neuroscience ( Frontiers in Neuroscience ) 17 1152959 - 1152959 2023.08 [Refereed]
Research paper (journal)
Previous studies suggest the importance of stable circadian environments for fetuses to achieve sound physiology and intrauterine development. This idea is also supported by epidemiological and animal studies, in which pregnant females exposed to repeated shifting of light-dark cycles had increased rates of reproductive abnormalities and adverse pregnancy outcomes. In response to such findings, artificial circadian environments with light-dark (LD) cycles have been introduced to NICUs to promote better physical development of preterm infants. Such LD cycles, however, may not be fully effective for preterm infants who are less than 30 weeks gestational age (WGA) since they are too premature to be adequately responsive to light. Instead, circadian rhythmicity of incubated preterm infants less than 30 WGA may be able to be developed through stimulation of the non-visual senses such as touch and sound.
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Fumiya Tanji, Syohei Miyamoto, Atsushi Iwasawa, Hidenobu Ohta, Kyoichi Ono
Journal of primary care & community health ( Journal of Primary Care and Community Health ) 14 21501319231212317 - 21501319231212317 2023 [Invited]
Research paper (journal)
INTRODUCTION: While there may be differences in the choice of suicide methods between attempters with and those without a history of psychiatric disorders, it is not clear whether these differences predict the actual degree of physical injury. The present study aimed to investigate the association between the history of psychiatric disorder and the degree of physical injury among suicide attempters in a Japanese rural area. METHODS: We conducted a cross-sectional study analyzing secondary data of 806 suicide attempters from April 2012 to March 2022 obtained from a Japanese rural city. The exposure variable was a history of psychiatric disorders. The primary outcome was the degree of physical injury of suicide attempters: moderate and severe. We conducted a multivariate Poisson regression analysis to estimate the prevalence ratios (PRs) and 95% confidence intervals (CIs). RESULTS: Among 806 suicide attempters, a significant negative association between the history of psychiatric disorder and the degree of physical injury was observed (PR = 0.40; 95% CI, 0.28-0.59). Those with and without psychiatric disorders were more likely to choose low- and severe-lethality suicide methods such as drug or psychotropic overdoses and hanging or deep wrist injuries, respectively (P < .001). CONCLUSIONS: The present study highlights the importance of considering suicide attempters, both with and without psychiatric disorders, while formulating targeted suicide prevention strategies.
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The shape of disposable diaper affects spontaneous movements of lower limbs in young infants.
Gima H, Teshima M, Tagami E, Sato T, Ohta H.
Sci Rep. 9 ( 1 ) 16176 2019.11 [Refereed]
Research paper (journal) Domestic Co-author
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アクティワッチ(小型照度・活動量計)による極低出生体重児の発達予後予測の可能性
下風 朋章, 太田 英伸, 兼次 洋介, 斎藤 朋子, 豊島 勝昭
日本新生児成育医学会雑誌 ( (公社)日本新生児成育医学会 ) 31 ( 3 ) 744 - 744 2019.10
Research paper (journal)
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Combined effects of body position and sleep status on the cardiorespiratory stability of near-term infants
Yoshihisa Oishi, Hidenobu Ohta, Takako Hirose, Sachiko Nakaya, Keiji Tsuchiya, Machiko Nakagawa, Isao Kusakawa, Toshihiro Sato, Toshimasa Obonai, Hiroshi Nishida, Hitoshi Yoda
Scientific Reports ( Nature Publishing Group ) 8 ( 1 ) 8845 2018.12
Research paper (journal)
The purpose of this study was to determine the effects of body position (prone, supine and lateral) together with sleep status (wake and sleep) on the cardiorespiratory stability of near-term infants. A total of 53 infants (gestational age at birth 33.2 ± 3.5 weeks
birth weight 1,682 ± 521 g
gestational age at recording 38.6 ± 2.1 weeks
weight at recording: 2,273 ± 393 g) were monitored for 24 hours for clinically significant apnea (>
15 seconds), bradycardia (<
100 bpm), and oxygen desaturation (SpO2 <
90%) in alternating body positions (prone, supine and lateral) by cardiorespiratory monitors and 3-orthogonal-axis accelerometers. Sleep status of the infants was also continuously monitored by actigraphs. No apnea was observed. During wake, severe bradycardia was most frequently observed in the lateral position while, during sleep, severe bradycardia was most frequently observed in the supine position. Desaturation was most frequently observed in the supine and lateral positions during both wake and sleep. Our study suggests that the cardiorespiratory stability of infants is significantly compromised by both body position and sleep status. During both wake and sleep, prone position induces the most stable cardiorespiratory functions of near-term infants. -
Entrainment of the Circadian Clock in Neural Stem Cells by Epidermal Growth Factor is Closely Associated with ERK1/2-mediated Induction of Multiple Clock-related Genes
Asuka Mogi, Ryo Yomoda, Syunya Kimura, Chisato Tsushima, Jun Takouda, Miho Sawauchi, Tomoko Maekawa, Hidenobu Ohta, Satoshi Nishino, Masatake Kurita, Nariyasu Mano, Noriko Osumi, Takahiro Moriya
Neuroscience ( Elsevier Ltd ) 379 45 - 66 2018.05
Research paper (journal)
The mitotic activity of certain tissues in the body is closely associated with circadian clock function. However, the effects of growth factors on the molecular clockwork are not fully understood. Stimulation of neural stem cells (NSCs) with epidermal growth factor (EGF), a well-known mitogen, is known to cause synchronized cell cycle progression with a period of approximately 24 h, closely associated with the Per2 gene expression rhythm. Here, we examined the effects of EGF on the molecular clockwork of NSCs. Treatment of cultured NSCs derived from embryonic mouse forebrain with EGF (20 ng/mL) caused a phase shift in the PER2::LUCIFERASE bioluminescence rhythm in a stimulation time-dependent manner. The EGF phase-response curve differed from that of forskolin (FK)—a well-known chemical resetting stimulus—both in the advance/delay ratio and stimulation time-dependency. PCR array analysis followed by quantitative PCR validation demonstrated that EGF treatment transiently induced multiple clock-related genes including Per1, Per2, Dec1, e4bp4, and Noct, whereas FK treatment induced a limited number of genes (Per1 and Dec1), suggesting that the mode of entrainment of NSC molecular clock was different for EGF and FK. EGF led to gene induction in the presence of cycloheximide, suggesting that de novo protein synthesis is unnecessary. Pretreatment with the MEK1/2 inhibitor U0126 significantly suppressed the acute induction of Per2, Dec1, and Noct by EGF and also abolished the EGF-induced phase shift of the PER2::LUCIFERASE rhythm in NSCs. These results suggest a unique effect of EGF on the molecular clockwork of NSCs.
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TSH and PRL, side-effect markers in aripiprazole treatment: Adjunctive aripiprazole-induced thyrotropin oversuppression in a young man with schizophrenia
Hidenobu Ohta, Satoru Inoue, Koichiro Hara, Akihiko Watanabe
BMJ Case Reports ( BMJ Publishing Group ) 2017 2017
Research paper (journal)
A 26-year-old Japanese man was admitted to our unit with exacerbated paranoid schizophrenia. Prior to his admission, daily administration of olanzapine had been sufficient to maintain a partial remission of his schizophrenia, but due to an exacerbation of his delusions, he had then also been prescribed aripiprazole, which had been followed by no improvement in symptoms and a gradual further exacerbation of auditory delusions. Physical examinations, brain MRI and neurophysiological assessment were unremarkable. Blood analysis, however, revealed extremely low thyroid-stimulating hormone (TSH) and prolactin-releasing hormone (PRL) concentration. Interestingly, after aripiprazole discontinuation, he returned to partial remission with an increase in plasma TSH and PRL concentration.
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Daytime nap controls toddlers' nighttime sleep
Machiko Nakagawa, Hidenobu Ohta, Yuko Nagaoki, Rinshu Shimabukuro, Yoko Asaka, Noriko Takahashi, Takayo Nakazawa, Yousuke Kaneshi, Keita Morioka, Yoshihisa Oishi, Yuriko Azami, Mari Ikeuchi, Mari Takahashi, Michio Hirata, Miwa Ozawa, Kazutoshi Cho, Isao Kusakawa, Hitoshi Yoda
SCIENTIFIC REPORTS ( NATURE PUBLISHING GROUP ) 6 27246 2016.06
Research paper (journal)
Previous studies have demonstrated that afternoon naps can have a negative effect on subsequent nighttime sleep in children. These studies have mainly been based on sleep questionnaires completed by parents. To investigate the effect of napping on such aspects of sleep quality, we performed a study in which child activity and sleep levels were recorded using actigraphy. The parents were asked to attach actigraphy units to their child's waist by an adjustable elastic belt and complete a sleep diary for 7 consecutive days. 50 healthy young toddlers of approximately 1.5 years of age were recruited. There was a significant negative correlation between nap duration and both nighttime sleep duration and sleep onset time, suggesting that long nap sleep induces short nighttime sleep duration and late sleep onset time. We also found a significant negative correlation between nap timing and nighttime sleep duration and also a significant positive correlation between nap timing and sleep onset time, suggesting that naps in the late afternoon also lead to short nighttime sleep duration and late sleep onset. Our findings suggest that duration-controlled naps starting early in the afternoon can induce a longer nighttime sleep in full-term infants of approximately 1.5 years of age.
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Influence of light exposure at nighttime on sleep development and body growth of preterm infants
Yosuke Kaneshi, Hidenobu Ohta, Keita Morioka, Itaru Hayasaka, Yutaka Uzuki, Takuma Akimoto, Akinori Moriichi, Machiko Nakagawa, Yoshihisa Oishi, Hisanori Wakamatsu, Naoki Honma, Hiroki Suma, Ryuichi Sakashita, Sei-ichi Tsujimura, Shigekazu Higuchi, Miyuki Shimokawara, Kazutoshi Cho, Hisanori Minakami
SCIENTIFIC REPORTS ( NATURE PUBLISHING GROUP ) 6 21680 2016.02
Research paper (journal)
Previous studies have demonstrated that a light-dark cycle has promoted better sleep development and weight gain in preterm infants than constant light or constant darkness. However, it was unknown whether brief light exposure at night for medical treatment and nursing care would compromise the benefits brought about by such a light-dark cycle. To examine such possibility, we developed a special red LED light with a wavelength of > 675 nm which preterm infants cannot perceive. Preterm infants born at < 36 weeks' gestational age were randomly assigned for periodic exposure to either white or red LED light at night in a light-dark cycle after transfer from the Neonatal Intensive Care Unit to the Growing Care Unit, used for supporting infants as they mature. Activity, nighttime crying and body weight were continuously monitored from enrolment until discharge. No significant difference in restactivity patterns, nighttime crying, or weight gain was observed between control and experimental groups. The data indicate that nursing care conducted at 3 to 4-hour intervals exposing infants to light for < 15 minutes does not prevent the infants from developing circadian rest-activity patterns, or proper body growth as long as the infants are exposed to regular light-dark cycles.
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Electrochemical analysis of optical switchable filter with a NiO thin film for high-performance incubators
K. Tajima, M. Nakagavva, Y. Oishi, H. Ohta
ECS Transactions ( Electrochemical Society Inc. ) 75 ( 51 ) 1 - 7 2016
Research paper (journal)
We report an optical switchable light filter fabricated from all solid-state materials for use in preterm infant incubators. The nickel oxide (NiO) thin film in the filter was fabricated by magnetron sputtering. The properties of the NiO thin film were also investigated. The optical switchable light filter also contained a W-Ir-0 thin film, because the widely used WO3 thin film shows an unsuitable EC color change to dark blue. The W-Ir-0 thin film did not absorb the longer wavelengths in the visible range, which is required for incubators. The optical switchable light filter containing the NiO thin film changed between pale yellow and dark yellow when a voltage was applied. The optical switching speed from the pale yellow to dark yellow state was around 60 s, and the reverse process was around 60 s. The fabrication of filters with a suitable color change for incubators requires further investigation.
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Artificial oxygen carriers rescue placental hypoxia and improve fetal development in the rat pre-eclampsia model
Heng Li, Hidenobu Ohta, Yu Tahara, Sakiko Nakamura, Kazuaki Taguchi, Machiko Nakagawa, Yoshihisa Oishi, Yu-ichi Goto, Keiji Wada, Makiko Kaga, Masumi Inagaki, Masaki Otagiri, Hideo Yokota, Shigenobu Shibata, Hiromi Sakai, Kunihiro Okamura, Nobuo Yaegashi
SCIENTIFIC REPORTS ( NATURE PUBLISHING GROUP ) 5 15271 2015.10
Research paper (journal)
Pre-eclampsia affects approximately 5% of all pregnant women and remains a major cause of maternal and fetal morbidity and mortality. The hypertension associated with pre-eclampsia develops during pregnancy and remits after delivery, suggesting that the placenta is the most likely origin of this disease. The pathophysiology involves insufficient trophoblast invasion, resulting in incomplete narrow placental spiral artery remodeling. Placental insufficiency, which limits the maternal-fetal exchange of gas and nutrients, leads to fetal intrauterine growth restriction. In this study, in our attempt to develop a new therapy for pre-eclampsia, we directly rescued placental and fetal hypoxia with nano-scale size artificial oxygen carriers (hemoglobin vesicles). The present study is the first to demonstrate that artificial oxygen carriers successfully treat placental hypoxia, decrease maternal plasma levels of anti-angiogenic proteins and ameliorate fetal growth restriction in the pre-eclampsia rat model.
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Correlation between umbilical cord hemoglobin and rate of jaundice requiring phototherapy in healthy newborns
Machiko Nakagawa, Yasushi Ishida, Yuko Nagaoki, Hidenobu Ohta, Rinshu Shimabukuro, Michio Hirata, Michiko Yamanaka, Isao Kusakawa
PEDIATRICS INTERNATIONAL ( WILEY-BLACKWELL ) 57 ( 4 ) 626 - 628 2015.08
Research paper (journal)
BackgroundDelay of umbilical cord clamping by at least 1min is recommended for newborns not requiring resuscitation in the International Liaison Committee On Resuscitation-Consensus on Science with Treatment Recommendations (ILCOR-CoSTR) 2010 guidelines. The delay in clamping improves iron status through early infancy but may increase the likelihood of jaundice requiring phototherapy. The present study investigated the relationship between umbilical cord hemoglobin and the rate of jaundice requiring phototherapy in healthy Japanese newborns.
MethodsCord hemoglobin was measured in healthy newborns and the rate of infants receiving phototherapy for jaundice and other data were obtained from medical records.
ResultsJaundice requiring phototherapy mostly occurred in association with high cord blood hemoglobin, which is increased by delayed cord clamping.
ConclusionsHigher cord hemoglobin may increase neonatal jaundice in newborns in Japan, therefore the present results support the Japan Resuscitation Council guideline 2010, which does not recommend delay of umbilical cord clamping by at least 1min, in contrast to the ILCOR guidelines. -
Designing artificial environments for preterm infants based on circadian studies on pregnant uterus.
Shimpei Watanabe, Shizuko Akiyama, Takushi Hanita, Heng Li, Machiko Nakagawa, Yousuke Kaneshi, Hidenobu Ohta
Frontiers in endocrinology 4 113 - 113 2013.09
Research paper (journal)
Using uterine explants from Per1::Luc rats and in situ hybridization, we recently reported that the circadian property of the molecular clock in the uterus and placenta is stably maintained from non-pregnancy, right through to the end stage of pregnancy under regular light-dark (LD) cycles. Despite long-lasting increases in progesterone during gestation and an increase in estrogen before delivery, the uterus keeps a stable Per1::Luc rhythm throughout the pregnancy. The study suggests the importance of stable circadian environments for fetuses to achieve sound physiology and intrauterine development. This idea is also supported by epidemiological and animal studies, in which pregnant females exposed to repeated shifting of the LD cycles have increased rates of reproductive abnormalities and adverse pregnancy outcomes. Leading from this, we introduced artificial circadian environments with controlled lighting conditions to human preterm infants by developing and utilizing a specific light filter which takes advantage of the unique characteristics of infants' developing visual photoreceptors. In spite of growing evidence of the physiological benefits of nighttime exposure to darkness for infant development, many Japanese Neonatal Intensive Care Units (NICUs) still prefer to maintain constant light in preparation for any possible emergencies concerning infants in incubators. To protect infants from the negative effects of constant light on their development in the NICU, we have developed a new device similar to a magic mirror, by which preterm infants can be shielded from exposure to their visible wavelengths of light even in the constant light conditions of the NICU while simultaneously allowing medical care staff to visually monitor preterm infants adequately. The device leads to significantly increased infant activity during daytime than during night time and better weight gains.
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Kazuki Tajima, Mika Shimoike, Heng Li, Masumi Inagaki, Hitomi Izumi, Misaki Akiyama, Yukiko Matsushima, Hidenobu Ohta
APPLIED PHYSICS LETTERS ( AMER INST PHYSICS ) 102 ( 16 ) 161913-161913-4 2013.04
Research paper (journal)
We have fabricated a controllable light filter using an all-solid-state switchable mirror incorporating a Mg-Ir thin film for use in preterm infant incubators. The solid-state switchable mirror device was fabricated by depositing a multilayer on a glass substrate. The mixed hydride of MgH2 and Mg6Ir2H11 created from the Mg-Ir thin film is red in the transparent state. The optical switching speeds between the reflective and transparent red states depended on applied voltage. The device showed three states, namely, reflective, black, and transparent red, due to the properties of the switchable mirror material. These results suggest that the material could be used as a controllable light filter for preterm infant incubators, since it eliminates the light wavelength that disturbs regular sleep-wake cycles of preterm infants. (C) 2013 AIP Publishing LLC. [http://dx.doi.org/10.1063/1.4801848]
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Behavioral and cortical EEG evaluations confirm the roles of both CCKA and CCKB receptors in mouse CCK-induced anxiety
Heng Li, Hidenobu Ohta, Hitomi Izumi, Yoshiki Matsuda, Mika Seki, Takako Toda, Misaki Akiyama, Yukiko Matsushima, Yu-ichi Goto, Makiko Kaga, Masumi Inagaki
BEHAVIOURAL BRAIN RESEARCH ( ELSEVIER SCIENCE BV ) 237 325 - 332 2013.01
Research paper (journal)
This study investigated the roles of cholecystokinin (CCK)(A) and CCKB receptors on CCK-4-induced anxiety-like behaviors in mice through behavioral and neural evaluations. Anxiety-like behaviors in mice were induced by an intracerebroventricular (icy.) administration of CCK-4, which can bind to both CCKA and CCKB receptors. The effects of CCKA and CCKB receptor antagonists (devazepide and CI-988, respectively) were examined using mouse anxiety tests (elevated-plus maze and light-dark box) and also by examining neuronal activities through EEG monitoring and c-Fos immunohistochemistry in the cortex and amygdala. CCK-4 (3 mu g/kg of body weight i.c.v.) significantly induced mouse anxiety-like behaviors in the anxiety tests and also affected their EEG patterns with respect to pre-drug tracing, resulting in increase in spectral power in relative power distribution in the delta and theta bands (0.5-5 Hz frequency bands) and also in increase in c-Fos immunopositive neuron counts. These CCK-4 effects were completely suppressed by 1.0 mg/kg CCKB receptor antagonist, CI-988, while the same amount of CCKA receptor antagonist, devazepide was partly able to suppress the same effects. These findings indicated that not only CCKB receptors but also CCKA receptors in the brain play important roles in regulating anxiety-like behaviors in mice. The present study also proposed a possibility that cortical EEG is useful for assessing anxiety. (C) 2012 Elsevier B.V. All rights reserved.
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Developmental change of visuo-spatial working memory in children: Quantitative evaluation through an Advanced Trail Making Test
Naomi Kokubo, Masumi Inagaki, Atsuko Gunji, Tomoka Kobayashi, Hidenobu Ohta, Osami Kajimoto, Makiko Kaga
BRAIN & DEVELOPMENT ( ELSEVIER SCIENCE BV ) 34 ( 10 ) 799 - 805 2012.11
Research paper (journal)
Aim: The present study aimed to investigate the developmental change in Visuo-Spatial Working Memory (VSWM) in typically developed children using a specially designed Advanced Trail Making Test for children (ATMT-C). Methods: We developed a new method for evaluating VSWM efficiency in children using a modified version ATMT to suit their shorter sustained attention. The ATMT-C consists of two parts; a number-based ATMT and a hiragana (Japanese phonogram)-based ATMT, both employing symbols familiar to young children. A total of 94 healthy participants (6-28 years of age) were enrolled in this study. Results: A non-linear developmental change of VSWM efficiency was observed in the results from the ATMT-C. In the number-based ATMT, children under 8 years of age showed a relatively rapid increase in VSWM efficiency while older children (9-12 years) had a more gradual increase in VSWM efficiency. Results from the hiragana-based ATMT-C showed a slightly delayed increase pattern in VSWM efficiency compared to the pattern from the number-based ATMT. There were no significant differences in VSWM efficiency for gender, handedness and test order. Interpretation: VSWM in children gradually matures in a non steady-state manner and there is an important stage for VSWM maturation before reaching 12 years of age. VSWM efficiency may also vary depending on developmental condition of its cognitive subsystems. (C) 2012 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.
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Liposome-encapsulated hemoglobin (hemoglobin-vesicle) is not transferred from mother to fetus at the late stage of pregnancy in the rat model
Maiko Kaga, Heng Li, Hidenobu Ohta, Kazuaki Taguchi, Shigeru Ogaki, Hitomi Izumi, Masumi Inagaki, Shigeru Tsuchiya, Kunihiro Okamura, Masaki Otagiri, Hiromi Sakai, Nobuo Yaegashi
LIFE SCIENCES ( PERGAMON-ELSEVIER SCIENCE LTD ) 91 ( 11-12 ) 420 - 428 2012.10
Research paper (journal)
Aims: Liposome-encapsulated hemoglobin (hemoglobin vesicles: HbV; diameter 250 nm) is reconstructed from human hemoglobin and developed as an artificial oxygen carrier for use as a transfusion alternative. Previous studies using rodent models closely investigated the safety of daily repeated infusions (DRI) of HbV and reported that the reticuloendothelial system was physiologically capable of degrading HbV to maintain plasma clinical chemistry within normal ranges. The present study examined the effect of DRI of HbV on the pregnant rat mother and fetal development, focusing on placental transfer of HbV in pregnancy.
Main methods: Pregnant rats intravenously received HbV bolus injections at 2 ml/kg/day for the last 7 consecutive days till term. The cumulative infusion volume (14 ml/kg) was equal to 25% of the whole blood volume (56 ml/kg).
Key findings: Maternal DRI of HbV had no obvious side effects on the pregnant mother or on fetal development. Maternal vital signs, plasma clinical chemistry, and blood gas parameters were overall normal after DRI of HbV. In addition, maternal/fetal transfer of HbV was limited to the placenta and HbV did not reach the fetus. Histopathological examination with human hemoglobin antibody detected HbV accumulation in the maternal spleen, liver, kidney, and placenta, but not in the fetuses. These results were also confirmed by a pharmacokinetic study using I-125-labeled HbV.
Significance: This safety study of HbV use in the pregnant mother and fetus will contribute to a possible application of HbV as a potential treatment for fetal hypoxia by supplying oxygen through the placenta. Crown Copyright (c) 2012 Published by Elsevier Inc. All rights reserved. -
Physiolgical capacity of the reticuloendothelial system for the degradation of hemoglobin-vesicles (artificial oxygen carriers) after massive intravenous doses by daily repeated infusion for 7 days in Pregnant rats and fetuses.
M. Kaga, H. Ohta, Y. Lee, R. Kamii, H. Yamamoto, S. Akiyama, S. Watanabe, T. Matsuda, Y. Kimura, S. Tsuchiya, H. Tei, L. Okamura, H. Sakai, N. Yaegashi
Life Sci. 91 420-428 2012
Research paper (journal)
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Antenatal Corticosteroids Promote Survival of Extremely Preterm Infants Born at 22 to 23 Weeks of Gestation
Rintaro Mori, Satoshi Kusuda, Masanori Fujimura
JOURNAL OF PEDIATRICS ( MOSBY-ELSEVIER ) 159 ( 1 ) 110 - U137 2011.07
Research paper (journal)
Objective To evaluate the effectiveness of antenatal corticosteroid (ACS) to improve neonatal outcomes for infants born at <24 weeks of gestation.
Study design We performed a retrospective analysis of 11 607 infants born at 22 to 33 weeks of gestation between 2003 and 2007 from the Neonatal Research Network of Japan. We evaluated the gestational age effects of ACS administered to mothers with threatened preterm birth on several factors related to neonatal morbidity and mortality.
Results By logistic regression analysis, ACS exposure decreased respiratory distress syndrome and severe intraventricular hemorrhage in infants born between 24 and 29 weeks of gestation. Cox regression analysis revealed that ACS exposure was associated with a significant decrease in mortality of preterm infants born at 22 or 23 weeks of gestation (adjusted hazard ratio, 0.72; 95% Cl, 0.53 to 0.97; P = .03). This effect was also observed at 24 to 25 and 26 to 27 weeks of gestation and in the overall study population.
Conclusions ACS exposure improved survival of extremely preterm infants. ACS treatment should be considered for threatened preterm birth at 22 to 23 weeks of gestation. (J Pediatr 2011; 159:110-4).