Early Mortality and Morbidity in Infants with Birth Weight of 500 Grams or Less in Japan

on behalf of the; Neonatal Research Network of Japan (NRNJ) Sapporo City General Hospital; Asahikawa Kosei General Hospital; Engaru-Kosei General Hospital; Kushiro Red Cross Hospital; Obihiro-Kosei General Hospital; Tenshi Hospital; NTT Higashinihon Sapporo Hospital; Nikko Memorial Hospital; Nayoro City General Hospital; Sapporo Medical University; Asahikawa Medical University; Aomori Prefectural Central Hospital; Iwate Medical University; Iwate Prefectural Ofunato Hospital; Iwate Prefectural Kuji Hospital; Iwate Prefectural Ninohe Hospital; Sendai Red Cross Hospital; Akita Red Cross Hospital; Tsuruoka Municipal Shonai Hospital; Yamagata University; Yamagata Prefectural Central Hospital; Fukushima Medical University; Takeda General Hospital; Fukushima National Hospital; Tsukuba University; Tsuchiura Kyodo Hospital; Ibaraki Children's Hospital; Dokkyo Medical University; Jichi Medical University; Ashikaga Red Cross Hospital; Gunma Children's Medical Center; Kiryu Kosei General Hospital; Fuji Heavy Industries Health Insurance Society Ota Memorial Hospital; Gunma University; Saitama Children's Medical Center; Nishisaitama-chuo National Hospital; Saitama Medical University Saitama Medical Center; Kawaguchi Municipal Medical Center; Jichi Medical University Saitama Medical Center; Asahi General Hospital; Chiba Kaihin Municipal Hospital; Kameda Medical Center; Tokyo Women's Medical University Yachiyo Medical Center; Juntendo University Urayasu Hospital; Tokyo Metropolitan Children's Medical Center; Tokyo Women's Medical University; Aiiku Hospital; Nihon University Itabashi Hospital; National Center for Global Health and Medicine; Tokyo Medical University; Teikyo University; Showa University; Japan Red Cross Medical Center; National Center for Child Health and Development; Tokyo Metropolitan Otsuka Hospital; Toho University; Tokyo Metropolitan Bokuto Hospital; Tokyo Jikei Medical University; Tokyo Medical and Dental University; Saint Luku's International Hospital; Juntendo University; Sanikukai Hospital; Katsushika Red Cross Hospital; Yokohama Rosai Hospital; Yokohama City University Medical Center; St. Marianna University School of Medicine Hospital; Kanagawa Children's Medical Center; Tokai University; Kitazato University; Odawara Municipal Hospital; Nippon Medical School Musashi Kosugi Hospital; Saiseikai Yokohamashi Tobu Hospital; National Hospital Organization Yokohama Medical Center; Yamanashi Prefectural Central Hospital; Nagano Children's Hospital; Shinshu University; Iida Municipal Hospital; National Hospital Organization Shinshu Ueda Medical Center; Saku General Hospital; Niigata University; Niigata Prefectural Central Hospital; Niigata Municipal Hospital; Nagaoka Red Cross Hospital; Koseiren Takaoka Hospital; Toyama Prefectural Central Hospital; Toyama University; Ishikawa Medical Center for Maternal and Child Health; Kanazawa Medical University; Kanazawa Medical Center; Fukui Prefectural Hospital; Fukui University; Gifu Prefectural General Medical Center; National Hospital Organization Nagara Medical Center; Takayama Red Cross Hospital; Seirei Hamamatsu Hospital; Shizuoka Saiseikai Hospital; Shizuoka Children's Hospital; Hamamatsu Medical University; Numazu Municipal Hospital; Yaizu City Hospital; Fujieda Municipal General Hospital; Nagoya Red Cross Daini Hospital; Nagoya University; Nagoya Red Cross Daiichi Hospital; Toyohashi Municipal Hospital; Nagoya City West Medical Center; Anjo Kosei Hospital; Tosei General Hospital; Komaki Municipal Hospital; TOYOTA Memorial Hospital; Okazaki Municipal Hospital; Konan Kosei Hospital; National Mie Central Medical Center; Ise Red Cross Hospital; Yokkaichi Municipal Hospital; Otsu Red Cross Hospital; Shiga University of Medical Science Hospital; Nagahama Red Cross Hospital; Uji Tokushukai Hospital; The Japan Baptist Hospital; Kyoto University; Kyoto Red Cross Daiichi Hospital; National Maizuru Medical Center; Fukuchiyama City Hospital; Kyoto Prefectural University of Medicine Hospital; Kyoto City Hospital; Mitsubishi Kyoto Hospital; Yodogawa Christian Hospital; Osaka Medical Center and Research Institute for Maternal and Child Health; Osaka University; Takatsuki General Hospital; Kansai Medical University; Osaka City General Hospital; Osaka City Sumiyoshi Hospital; Aizenbashi Hospital; Toyonaka Municipal Hospital; National Cerebral and Cardiovascular Center, Kitano Hospital; Saiseikai Suita Hospital; Chifune Hospital; Bellland General Hospital; Rinku General Medical Center; Osaka Red Cross Hospital; Yao Municipal Hospital; Osaka General Medical Center; Osaka City University; Hyogo Prefectural Kobe Children's Hospital; Kobe University; Kakogawa West City Hospital; Saiseikai Hyogoken Hospital; Kobe City Medical Center General Hospital; Hyogo College of Medicine Hospital; Himeji Red Cross Hospital; Toyooka Public Hospital; Hyogo Prefectural Awaji Medical Center; Nara Medical University; Wakayama Medical University; Tottori Prefectural Central Hospital; Tottori University; Shimane Prefectural Central Hospital; Matsue Red Cross Hospital; Kurashiki Central Hospital; Tsuyama Central Hospital; Kawasaki Medical School Hospital; National Hospital Organization Okayama Medical Center; Okayama Red Cross Hospital; Hiroshima City Hiroshima Citizens Hospital; Hiroshima Prefectural Hospital; Hiroshima University; Tsuchiya General Hospital; National Hospital Organization Kure Medical Center; Yamaguchi University; Yamaguchi Grand Medical Center; Tokushima University; Tokushima Municipal Hospital; Kagawa University; National Hospital Organization Kagawa Children's Hospital; Matsuyama Red Cross Hospital; Ehime Prefectural Central Hospital; Kochi Health Science Center; St.Mary's Hospital; National Kyushu Medical Center; Kurume University; Kitakyushu Municipal Medical Center; University of Occupational and Environmental Health; Fukuoka University; Kyushu University; Iizuka Hospital; National Hospital Organization Kokura Medical Center; National Hospital Organization Saga Hospital; National Hospital Organization Nagasaki Medical Center; Kumamoto City Hospital; Kumamoto University; Oita Prefectural Hospital; Almeida Memorial Hospital; Nakatsu Municipal Hospital; Miyazaki University; National Hospital Organization Miyakonojo Medical Center; Kagoshima City Hospital; Imakiire General Hospital; Okinawa Prefectural Nanbu Medical Center & Children's Medical Center; Okinawa Prefectural Chubu Hospital; Naha City Hospital; Okinawa Red Cross Hospital

doi:10.1016/j.jpeds.2017.05.017

Early Mortality and Morbidity in Infants with Birth Weight of 500 Grams or Less in Japan

on behalf of the, Neonatal Research Network of Japan (NRNJ) Sapporo City General Hospital, Asahikawa Kosei General Hospital, Engaru-Kosei General Hospital, Kushiro Red Cross Hospital, Obihiro-Kosei General Hospital, Tenshi Hospital, NTT Higashinihon Sapporo Hospital, Nikko Memorial Hospital, Nayoro City General Hospital, Sapporo Medical University, Asahikawa Medical University, Aomori Prefectural Central Hospital, Iwate Medical University, Iwate Prefectural Ofunato Hospital, Iwate Prefectural Kuji Hospital, Iwate Prefectural Ninohe Hospital, Sendai Red Cross Hospital, Akita Red Cross Hospital, Tsuruoka Municipal Shonai HospitalYamagata University, Yamagata Prefectural Central Hospital, Fukushima Medical University, Takeda General Hospital, Fukushima National Hospital, Tsukuba University, Tsuchiura Kyodo Hospital, Ibaraki Children's Hospital, Dokkyo Medical University, Jichi Medical University, Ashikaga Red Cross Hospital, Gunma Children's Medical Center, Kiryu Kosei General Hospital, Fuji Heavy Industries Health Insurance Society Ota Memorial Hospital, Gunma University, Saitama Children's Medical Center, Nishisaitama-chuo National Hospital, Saitama Medical University Saitama Medical Center, Kawaguchi Municipal Medical Center, Jichi Medical University Saitama Medical Center, Asahi General Hospital, Chiba Kaihin Municipal Hospital, Kameda Medical Center, Tokyo Women's Medical University Yachiyo Medical Center, Juntendo University Urayasu Hospital, Tokyo Metropolitan Children's Medical Center, Tokyo Women's Medical University, Aiiku Hospital, Nihon University Itabashi Hospital, National Center for Global Health and Medicine, Tokyo Medical University, Teikyo University, Showa University, Japan Red Cross Medical Center, National Center for Child Health and Development, Tokyo Metropolitan Otsuka Hospital, Toho University, Tokyo Metropolitan Bokuto Hospital, Tokyo Jikei Medical University, Tokyo Medical and Dental University, Saint Luku's International Hospital, Juntendo University, Sanikukai Hospital, Katsushika Red Cross Hospital, Yokohama Rosai Hospital, Yokohama City University Medical Center, St. Marianna University School of Medicine Hospital, Kanagawa Children's Medical Center, Tokai University, Kitazato University, Odawara Municipal Hospital, Nippon Medical School Musashi Kosugi Hospital, Saiseikai Yokohamashi Tobu Hospital, National Hospital Organization Yokohama Medical Center, Yamanashi Prefectural Central Hospital, Nagano Children's Hospital, Shinshu University, Iida Municipal Hospital, National Hospital Organization Shinshu Ueda Medical Center, Saku General Hospital, Niigata University, Niigata Prefectural Central Hospital, Niigata Municipal Hospital, Nagaoka Red Cross Hospital, Koseiren Takaoka Hospital, Toyama Prefectural Central Hospital, Toyama University, Ishikawa Medical Center for Maternal and Child Health, Kanazawa Medical University, Kanazawa Medical Center, Fukui Prefectural Hospital, Fukui University, Gifu Prefectural General Medical Center, National Hospital Organization Nagara Medical Center, Takayama Red Cross Hospital, Seirei Hamamatsu Hospital, Shizuoka Saiseikai Hospital, Shizuoka Children's Hospital, Hamamatsu Medical University, Numazu Municipal Hospital, Yaizu City Hospital, Fujieda Municipal General Hospital, Nagoya Red Cross Daini Hospital, Nagoya University, Nagoya Red Cross Daiichi Hospital, Toyohashi Municipal Hospital, Nagoya City West Medical Center, Anjo Kosei Hospital, Tosei General Hospital, Komaki Municipal Hospital, TOYOTA Memorial Hospital, Okazaki Municipal Hospital, Konan Kosei Hospital, National Mie Central Medical Center, Ise Red Cross Hospital, Yokkaichi Municipal Hospital, Otsu Red Cross Hospital, Shiga University of Medical Science Hospital, Nagahama Red Cross Hospital, Uji Tokushukai Hospital, The Japan Baptist Hospital, Kyoto University, Kyoto Red Cross Daiichi Hospital, National Maizuru Medical Center, Fukuchiyama City Hospital, Kyoto Prefectural University of Medicine Hospital, Kyoto City Hospital, Mitsubishi Kyoto Hospital, Yodogawa Christian Hospital, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka University, Takatsuki General Hospital, Kansai Medical University, Osaka City General Hospital, Osaka City Sumiyoshi Hospital, Aizenbashi Hospital, Toyonaka Municipal Hospital, National Cerebral and Cardiovascular Center, Kitano Hospital, Saiseikai Suita Hospital, Chifune Hospital, Bellland General Hospital, Rinku General Medical Center, Osaka Red Cross Hospital, Yao Municipal Hospital, Osaka General Medical Center, Osaka City University, Hyogo Prefectural Kobe Children's Hospital, Kobe University, Kakogawa West City Hospital, Saiseikai Hyogoken Hospital, Kobe City Medical Center General Hospital, Hyogo College of Medicine Hospital, Himeji Red Cross Hospital, Toyooka Public Hospital, Hyogo Prefectural Awaji Medical Center, Nara Medical University, Wakayama Medical University, Tottori Prefectural Central Hospital, Tottori University, Shimane Prefectural Central Hospital, Matsue Red Cross Hospital, Kurashiki Central Hospital, Tsuyama Central Hospital, Kawasaki Medical School Hospital, National Hospital Organization Okayama Medical Center, Okayama Red Cross Hospital, Hiroshima City Hiroshima Citizens Hospital, Hiroshima Prefectural Hospital, Hiroshima University, Tsuchiya General Hospital, National Hospital Organization Kure Medical Center, Yamaguchi University, Yamaguchi Grand Medical Center, Tokushima University, Tokushima Municipal Hospital, Kagawa University, National Hospital Organization Kagawa Children's Hospital, Matsuyama Red Cross Hospital, Ehime Prefectural Central Hospital, Kochi Health Science Center, St.Mary's Hospital, National Kyushu Medical Center, Kurume University, Kitakyushu Municipal Medical Center, University of Occupational and Environmental Health, Fukuoka University, Kyushu University, Iizuka Hospital, National Hospital Organization Kokura Medical Center, National Hospital Organization Saga Hospital, National Hospital Organization Nagasaki Medical Center, Kumamoto City Hospital, Kumamoto University, Oita Prefectural Hospital, Almeida Memorial Hospital, Nakatsu Municipal Hospital, Miyazaki University, National Hospital Organization Miyakonojo Medical Center, Kagoshima City Hospital, Imakiire General Hospital, Okinawa Prefectural Nanbu Medical Center & Children's Medical Center, Okinawa Prefectural Chubu Hospital, Naha City Hospital, Okinawa Red Cross Hospital

Research output: Contribution to journal › Article › peer-review

40 Citations (Scopus)

Abstract

Objective To assess the short-term prognosis of Japanese infants with a birth weight (BW) of ≤500 g. Study design Demographic and clinical data were reviewed for 1473 live born infants with a BW ≤500 g at gestational age ≥22 weeks who were treated in the 204 affiliated hospitals of the Neonatal Research Network of Japan between 2003 and 2012. Results Survival to hospital discharge occurred in 811 of 1473 infants (55%; 95% CI 53%-58%). The survival rates of BW ≤300 g, 301-400 g, and 401-500 g were 18% (95% CI 10%-31%), 41% (95% CI 36%-47%), and 60% (95% CI 57%-63%), respectively. In a multivariable Cox proportional hazards analysis, antenatal corticosteroid use (adjusted hazard ratio: 0.68; 95% CI 0.58-0.81; P <.01), cesarean delivery (0.69; 95% CI 0.56-0.85; P <.01), advanced gestational age per week (0.94; 95% CI 0.89-0.99; P =.02), BW per 100-g increase (0.55; 95% CI 0.49-0.64; P <.01), Apgar score ≥4 at 5 minutes (0.51; 95% CI 0.43-0.61; P <.01), and no major congenital abnormalities (0.38; 95% CI 0.29-0.51; P <.01) were associated with survival to discharge. Despite the improved survival rate over the 10-year study period (from 40% in 2003 [95% CI 30%-51%] to 68% in 2012 [95% CI 61%-75%]), at least 1 severe morbidity was present in 81%-89% of the survivors. Conclusions Improvements in perinatal-neonatal medicine have improved the survival, but not the rate of major morbidities, of infants with a BW ≤500 g in Japan.

Original language	English
Pages (from-to)	112-117.e3
Journal	Journal of Pediatrics
Volume	190
DOIs	https://doi.org/10.1016/j.jpeds.2017.05.017
Publication status	Published - Nov 2017

All Science Journal Classification (ASJC) codes

Pediatrics, Perinatology, and Child Health

Access to Document

10.1016/j.jpeds.2017.05.017

Cite this

on behalf of the, Neonatal Research Network of Japan (NRNJ) Sapporo City General Hospital, Asahikawa Kosei General Hospital, Engaru-Kosei General Hospital, Kushiro Red Cross Hospital, Obihiro-Kosei General Hospital, Tenshi Hospital, NTT Higashinihon Sapporo Hospital, Nikko Memorial Hospital, Nayoro City General Hospital, Sapporo Medical University, Asahikawa Medical University, Aomori Prefectural Central Hospital, Iwate Medical University, Iwate Prefectural Ofunato Hospital, Iwate Prefectural Kuji Hospital, Iwate Prefectural Ninohe Hospital, Sendai Red Cross Hospital, Akita Red Cross Hospital, ... Okinawa Red Cross Hospital (2017). Early Mortality and Morbidity in Infants with Birth Weight of 500 Grams or Less in Japan. Journal of Pediatrics, 190, 112-117.e3. https://doi.org/10.1016/j.jpeds.2017.05.017

on behalf of the, Neonatal Research Network of Japan (NRNJ) Sapporo City General Hospital, Asahikawa Kosei General Hospital, Engaru-Kosei General Hospital, Kushiro Red Cross Hospital, Obihiro-Kosei General Hospital, Tenshi Hospital, NTT Higashinihon Sapporo Hospital, Nikko Memorial Hospital, Nayoro City General Hospital, Sapporo Medical University, Asahikawa Medical University, Aomori Prefectural Central Hospital, Iwate Medical University, Iwate Prefectural Ofunato Hospital, Iwate Prefectural Kuji Hospital, Iwate Prefectural Ninohe Hospital, Sendai Red Cross Hospital, Akita Red Cross Hospital, Tsuruoka Municipal Shonai Hospital, Yamagata University, Yamagata Prefectural Central Hospital, Fukushima Medical University, Takeda General Hospital, Fukushima National Hospital, Tsukuba University, Tsuchiura Kyodo Hospital, Ibaraki Children's Hospital, Dokkyo Medical University, Jichi Medical University, Ashikaga Red Cross Hospital, Gunma Children's Medical Center, Kiryu Kosei General Hospital, Fuji Heavy Industries Health Insurance Society Ota Memorial Hospital, Gunma University, Saitama Children's Medical Center, Nishisaitama-chuo National Hospital, Saitama Medical University Saitama Medical Center, Kawaguchi Municipal Medical Center, Jichi Medical University Saitama Medical Center, Asahi General Hospital, Chiba Kaihin Municipal Hospital, Kameda Medical Center, Tokyo Women's Medical University Yachiyo Medical Center, Juntendo University Urayasu Hospital, Tokyo Metropolitan Children's Medical Center, Tokyo Women's Medical University, Aiiku Hospital, Nihon University Itabashi Hospital, National Center for Global Health and Medicine, Tokyo Medical University, Teikyo University, Showa University, Japan Red Cross Medical Center, National Center for Child Health and Development, Tokyo Metropolitan Otsuka Hospital, Toho University, Tokyo Metropolitan Bokuto Hospital, Tokyo Jikei Medical University, Tokyo Medical and Dental University, Saint Luku's International Hospital, Juntendo University, Sanikukai Hospital, Katsushika Red Cross Hospital, Yokohama Rosai Hospital, Yokohama City University Medical Center, St. Marianna University School of Medicine Hospital, Kanagawa Children's Medical Center, Tokai University, Kitazato University, Odawara Municipal Hospital, Nippon Medical School Musashi Kosugi Hospital, Saiseikai Yokohamashi Tobu Hospital, National Hospital Organization Yokohama Medical Center, Yamanashi Prefectural Central Hospital, Nagano Children's Hospital, Shinshu University, Iida Municipal Hospital, National Hospital Organization Shinshu Ueda Medical Center, Saku General Hospital, Niigata University, Niigata Prefectural Central Hospital, Niigata Municipal Hospital, Nagaoka Red Cross Hospital, Koseiren Takaoka Hospital, Toyama Prefectural Central Hospital, Toyama University, Ishikawa Medical Center for Maternal and Child Health, Kanazawa Medical University, Kanazawa Medical Center, Fukui Prefectural Hospital, Fukui University, Gifu Prefectural General Medical Center, National Hospital Organization Nagara Medical Center, Takayama Red Cross Hospital, Seirei Hamamatsu Hospital, Shizuoka Saiseikai Hospital, Shizuoka Children's Hospital, Hamamatsu Medical University, Numazu Municipal Hospital, Yaizu City Hospital, Fujieda Municipal General Hospital, Nagoya Red Cross Daini Hospital, Nagoya University, Nagoya Red Cross Daiichi Hospital, Toyohashi Municipal Hospital, Nagoya City West Medical Center, Anjo Kosei Hospital, Tosei General Hospital, Komaki Municipal Hospital, TOYOTA Memorial Hospital, Okazaki Municipal Hospital, Konan Kosei Hospital, National Mie Central Medical Center, Ise Red Cross Hospital, Yokkaichi Municipal Hospital, Otsu Red Cross Hospital, Shiga University of Medical Science Hospital, Nagahama Red Cross Hospital, Uji Tokushukai Hospital, The Japan Baptist Hospital, Kyoto University, Kyoto Red Cross Daiichi Hospital, National Maizuru Medical Center, Fukuchiyama City Hospital, Kyoto Prefectural University of Medicine Hospital, Kyoto City Hospital, Mitsubishi Kyoto Hospital, Yodogawa Christian Hospital, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka University, Takatsuki General Hospital, Kansai Medical University, Osaka City General Hospital, Osaka City Sumiyoshi Hospital, Aizenbashi Hospital, Toyonaka Municipal Hospital, National Cerebral and Cardiovascular Center, Kitano Hospital, Saiseikai Suita Hospital, Chifune Hospital, Bellland General Hospital, Rinku General Medical Center, Osaka Red Cross Hospital, Yao Municipal Hospital, Osaka General Medical Center, Osaka City University, Hyogo Prefectural Kobe Children's Hospital, Kobe University, Kakogawa West City Hospital, Saiseikai Hyogoken Hospital, Kobe City Medical Center General Hospital, Hyogo College of Medicine Hospital, Himeji Red Cross Hospital, Toyooka Public Hospital, Hyogo Prefectural Awaji Medical Center, Nara Medical University, Wakayama Medical University, Tottori Prefectural Central Hospital, Tottori University, Shimane Prefectural Central Hospital, Matsue Red Cross Hospital, Kurashiki Central Hospital, Tsuyama Central Hospital, Kawasaki Medical School Hospital, National Hospital Organization Okayama Medical Center, Okayama Red Cross Hospital, Hiroshima City Hiroshima Citizens Hospital, Hiroshima Prefectural Hospital, Hiroshima University, Tsuchiya General Hospital, National Hospital Organization Kure Medical Center, Yamaguchi University, Yamaguchi Grand Medical Center, Tokushima University, Tokushima Municipal Hospital, Kagawa University, National Hospital Organization Kagawa Children's Hospital, Matsuyama Red Cross Hospital, Ehime Prefectural Central Hospital, Kochi Health Science Center, St.Mary's Hospital, National Kyushu Medical Center, Kurume University, Kitakyushu Municipal Medical Center, University of Occupational and Environmental Health, Fukuoka University, Kyushu University, Iizuka Hospital, National Hospital Organization Kokura Medical Center, National Hospital Organization Saga Hospital, National Hospital Organization Nagasaki Medical Center, Kumamoto City Hospital, Kumamoto University, Oita Prefectural Hospital, Almeida Memorial Hospital, Nakatsu Municipal Hospital, Miyazaki University, National Hospital Organization Miyakonojo Medical Center, Kagoshima City Hospital, Imakiire General Hospital, Okinawa Prefectural Nanbu Medical Center & Children's Medical Center, Okinawa Prefectural Chubu Hospital, Naha City Hospital & Okinawa Red Cross Hospital 2017, 'Early Mortality and Morbidity in Infants with Birth Weight of 500 Grams or Less in Japan', Journal of Pediatrics, vol. 190, pp. 112-117.e3. https://doi.org/10.1016/j.jpeds.2017.05.017

on behalf of the, Neonatal Research Network of Japan (NRNJ) Sapporo City General Hospital, Asahikawa Kosei General Hospital, Engaru-Kosei General Hospital, Kushiro Red Cross Hospital, Obihiro-Kosei General Hospital et al. Early Mortality and Morbidity in Infants with Birth Weight of 500 Grams or Less in Japan. Journal of Pediatrics. 2017 Nov;190:112-117.e3. doi: 10.1016/j.jpeds.2017.05.017

@article{683006e6a9c646cd98de1dba95d7dd47,

title = "Early Mortality and Morbidity in Infants with Birth Weight of 500 Grams or Less in Japan",

abstract = "Objective To assess the short-term prognosis of Japanese infants with a birth weight (BW) of ≤500 g. Study design Demographic and clinical data were reviewed for 1473 live born infants with a BW ≤500 g at gestational age ≥22 weeks who were treated in the 204 affiliated hospitals of the Neonatal Research Network of Japan between 2003 and 2012. Results Survival to hospital discharge occurred in 811 of 1473 infants (55%; 95% CI 53%-58%). The survival rates of BW ≤300 g, 301-400 g, and 401-500 g were 18% (95% CI 10%-31%), 41% (95% CI 36%-47%), and 60% (95% CI 57%-63%), respectively. In a multivariable Cox proportional hazards analysis, antenatal corticosteroid use (adjusted hazard ratio: 0.68; 95% CI 0.58-0.81; P <.01), cesarean delivery (0.69; 95% CI 0.56-0.85; P <.01), advanced gestational age per week (0.94; 95% CI 0.89-0.99; P =.02), BW per 100-g increase (0.55; 95% CI 0.49-0.64; P <.01), Apgar score ≥4 at 5 minutes (0.51; 95% CI 0.43-0.61; P <.01), and no major congenital abnormalities (0.38; 95% CI 0.29-0.51; P <.01) were associated with survival to discharge. Despite the improved survival rate over the 10-year study period (from 40% in 2003 [95% CI 30%-51%] to 68% in 2012 [95% CI 61%-75%]), at least 1 severe morbidity was present in 81%-89% of the survivors. Conclusions Improvements in perinatal-neonatal medicine have improved the survival, but not the rate of major morbidities, of infants with a BW ≤500 g in Japan.",

author = "{on behalf of the} and {Neonatal Research Network of Japan (NRNJ) Sapporo City General Hospital} and {Asahikawa Kosei General Hospital} and {Engaru-Kosei General Hospital} and {Kushiro Red Cross Hospital} and {Obihiro-Kosei General Hospital} and {Tenshi Hospital} and {NTT Higashinihon Sapporo Hospital} and {Nikko Memorial Hospital} and {Nayoro City General Hospital} and {Sapporo Medical University} and {Asahikawa Medical University} and {Aomori Prefectural Central Hospital} and {Iwate Medical University} and {Iwate Prefectural Ofunato Hospital} and {Iwate Prefectural Kuji Hospital} and {Iwate Prefectural Ninohe Hospital} and {Sendai Red Cross Hospital} and {Akita Red Cross Hospital} and {Tsuruoka Municipal Shonai Hospital} and {Yamagata University} and {Yamagata Prefectural Central Hospital} and {Fukushima Medical University} and {Takeda General Hospital} and {Fukushima National Hospital} and {Tsukuba University} and {Tsuchiura Kyodo Hospital} and {Ibaraki Children's Hospital} and {Dokkyo Medical University} and {Jichi Medical University} and {Ashikaga Red Cross Hospital} and {Gunma Children's Medical Center} and {Kiryu Kosei General Hospital} and {Fuji Heavy Industries Health Insurance Society Ota Memorial Hospital} and {Gunma University} and {Saitama Children's Medical Center} and {Nishisaitama-chuo National Hospital} and {Saitama Medical University Saitama Medical Center} and {Kawaguchi Municipal Medical Center} and {Jichi Medical University Saitama Medical Center} and {Asahi General Hospital} and {Chiba Kaihin Municipal Hospital} and {Kameda Medical Center} and {Tokyo Women's Medical University Yachiyo Medical Center} and {Juntendo University Urayasu Hospital} and {Tokyo Metropolitan Children's Medical Center} and {Tokyo Women's Medical University} and {Aiiku Hospital} and {Nihon University Itabashi Hospital} and {National Center for Global Health and Medicine} and {Tokyo Medical University} and {Teikyo University} and {Showa University} and {Japan Red Cross Medical Center} and {National Center for Child Health and Development} and {Tokyo Metropolitan Otsuka Hospital} and {Toho University} and {Tokyo Metropolitan Bokuto Hospital} and {Tokyo Jikei Medical University} and {Tokyo Medical and Dental University} and {Saint Luku's International Hospital} and {Juntendo University} and {Sanikukai Hospital} and {Katsushika Red Cross Hospital} and {Yokohama Rosai Hospital} and {Yokohama City University Medical Center} and {St. Marianna University School of Medicine Hospital} and {Kanagawa Children's Medical Center} and {Tokai University} and {Kitazato University} and {Odawara Municipal Hospital} and {Nippon Medical School Musashi Kosugi Hospital} and {Saiseikai Yokohamashi Tobu Hospital} and {National Hospital Organization Yokohama Medical Center} and {Yamanashi Prefectural Central Hospital} and {Nagano Children's Hospital} and {Shinshu University} and {Iida Municipal Hospital} and {National Hospital Organization Shinshu Ueda Medical Center} and {Saku General Hospital} and {Niigata University} and {Niigata Prefectural Central Hospital} and {Niigata Municipal Hospital} and {Nagaoka Red Cross Hospital} and {Koseiren Takaoka Hospital} and {Toyama Prefectural Central Hospital} and {Toyama University} and {Ishikawa Medical Center for Maternal and Child Health} and {Kanazawa Medical University} and {Kanazawa Medical Center} and {Fukui Prefectural Hospital} and {Fukui University} and {Gifu Prefectural General Medical Center} and {National Hospital Organization Nagara Medical Center} and {Takayama Red Cross Hospital} and {Seirei Hamamatsu Hospital} and {Shizuoka Saiseikai Hospital} and {Shizuoka Children's Hospital} and {Hamamatsu Medical University} and {Numazu Municipal Hospital} and {Yaizu City Hospital} and {Fujieda Municipal General Hospital} and {Nagoya Red Cross Daini Hospital} and {Nagoya University} and {Nagoya Red Cross Daiichi Hospital} and {Toyohashi Municipal Hospital} and {Nagoya City West Medical Center} and {Anjo Kosei Hospital} and {Tosei General Hospital} and {Komaki Municipal Hospital} and {TOYOTA Memorial Hospital} and {Okazaki Municipal Hospital} and {Konan Kosei Hospital} and {National Mie Central Medical Center} and {Ise Red Cross Hospital} and {Yokkaichi Municipal Hospital} and {Otsu Red Cross Hospital} and {Shiga University of Medical Science Hospital} and {Nagahama Red Cross Hospital} and {Uji Tokushukai Hospital} and {The Japan Baptist Hospital} and {Kyoto University} and {Kyoto Red Cross Daiichi Hospital} and {National Maizuru Medical Center} and {Fukuchiyama City Hospital} and {Kyoto Prefectural University of Medicine Hospital} and {Kyoto City Hospital} and {Mitsubishi Kyoto Hospital} and {Yodogawa Christian Hospital} and {Osaka Medical Center and Research Institute for Maternal and Child Health} and {Osaka University} and {Takatsuki General Hospital} and {Kansai Medical University} and {Osaka City General Hospital} and {Osaka City Sumiyoshi Hospital} and {Aizenbashi Hospital} and {Toyonaka Municipal Hospital} and {National Cerebral and Cardiovascular Center, Kitano Hospital} and {Saiseikai Suita Hospital} and {Chifune Hospital} and {Bellland General Hospital} and {Rinku General Medical Center} and {Osaka Red Cross Hospital} and {Yao Municipal Hospital} and {Osaka General Medical Center} and {Osaka City University} and {Hyogo Prefectural Kobe Children's Hospital} and {Kobe University} and {Kakogawa West City Hospital} and {Saiseikai Hyogoken Hospital} and {Kobe City Medical Center General Hospital} and {Hyogo College of Medicine Hospital} and {Himeji Red Cross Hospital} and {Toyooka Public Hospital} and {Hyogo Prefectural Awaji Medical Center} and {Nara Medical University} and {Wakayama Medical University} and {Tottori Prefectural Central Hospital} and {Tottori University} and {Shimane Prefectural Central Hospital} and {Matsue Red Cross Hospital} and {Kurashiki Central Hospital} and {Tsuyama Central Hospital} and {Kawasaki Medical School Hospital} and {National Hospital Organization Okayama Medical Center} and {Okayama Red Cross Hospital} and {Hiroshima City Hiroshima Citizens Hospital} and {Hiroshima Prefectural Hospital} and {Hiroshima University} and {Tsuchiya General Hospital} and {National Hospital Organization Kure Medical Center} and {Yamaguchi University} and {Yamaguchi Grand Medical Center} and {Tokushima University} and {Tokushima Municipal Hospital} and {Kagawa University} and {National Hospital Organization Kagawa Children's Hospital} and {Matsuyama Red Cross Hospital} and {Ehime Prefectural Central Hospital} and {Kochi Health Science Center} and {St.Mary's Hospital} and {National Kyushu Medical Center} and {Kurume University} and {Kitakyushu Municipal Medical Center} and {University of Occupational and Environmental Health} and {Fukuoka University} and {Kyushu University} and {Iizuka Hospital} and {National Hospital Organization Kokura Medical Center} and {National Hospital Organization Saga Hospital} and {National Hospital Organization Nagasaki Medical Center} and {Kumamoto City Hospital} and {Kumamoto University} and {Oita Prefectural Hospital} and {Almeida Memorial Hospital} and {Nakatsu Municipal Hospital} and {Miyazaki University} and {National Hospital Organization Miyakonojo Medical Center} and {Kagoshima City Hospital} and {Imakiire General Hospital} and {Okinawa Prefectural Nanbu Medical Center & Children's Medical Center} and {Okinawa Prefectural Chubu Hospital} and {Naha City Hospital} and {Okinawa Red Cross Hospital} and Hirosuke Inoue and Masayuki Ochiai and Kazuaki Yasuoka and Koichi Tanaka and Hiroaki Kurata and Junko Fujiyoshi and Yuki Matsushita and Shutaro Suga and Kazuaki Nonaka and Tomoaki Taguchi and Kiyoko Kato and Shouichi Ohga",

note = "Funding Information: Institutions enrolled in the study of the Neonatal Research Network, Japan, include: Sapporo City General Hospital, Asahikawa Kosei General Hospital, Engaru-Kosei General Hospital, Kushiro Red Cross Hospital, Obihiro-Kosei General Hospital, Tenshi Hospital, NTT Higashinihon Sapporo Hospital, Nikko Memorial Hospital, Nayoro City General Hospital, Sapporo Medical University, Asahikawa Medical University, Aomori Prefectural Central Hospital, Iwate Medical University, Iwate Prefectural Ofunato Hospital, Iwate Prefectural Kuji Hospital, Iwate Prefectural Ninohe Hospital, Sendai Red Cross Hospital, Akita Red Cross Hospital, Tsuruoka Municipal Shonai Hospital, Yamagata University, Yamagata Prefectural Central Hospital, Fukushima Medical University, Takeda General Hospital, Fukushima National Hospital, Tsukuba University, Tsuchiura Kyodo Hospital, Ibaraki Children's Hospital, Dokkyo Medical University, Jichi Medical University, Ashikaga Red Cross Hospital, Gunma Children's Medical Center, Kiryu Kosei General Hospital, Fuji Heavy Industries Health Insurance Society Ota Memorial Hospital, Gunma University, Saitama Children's Medical Center, Nishisaitama-chuo National Hospital, Saitama Medical University Saitama Medical Center, Kawaguchi Municipal Medical Center, Jichi Medical University Saitama Medical Center, Asahi General Hospital, Chiba Kaihin Municipal Hospital, Kameda Medical Center, Tokyo Women's Medical University Yachiyo Medical Center, Juntendo University Urayasu Hospital, Tokyo Metropolitan Children's Medical Center, Tokyo Women's Medical University, Aiiku Hospital, Nihon University Itabashi Hospital, National Center for Global Health and Medicine, Tokyo Medical University, Teikyo University, Showa University, Japan Red Cross Medical Center, National Center for Child Health and Development, Tokyo Metropolitan Otsuka Hospital, Toho University, Tokyo Metropolitan Bokuto Hospital, Tokyo Jikei Medical University, Tokyo Medical and Dental University, Saint Luku's International Hospital, Juntendo University, Sanikukai Hospital, Katsushika Red Cross Hospital, Yokohama Rosai Hospital, Yokohama City University Medical Center, St. Marianna University School of Medicine Hospital, Kanagawa Children's Medical Center, Tokai University, Kitazato University, Odawara Municipal Hospital, Nippon Medical School Musashi Kosugi Hospital, Saiseikai Yokohamashi Tobu Hospital, National Hospital Organization Yokohama Medical Center, Yamanashi Prefectural Central Hospital, Nagano Children's Hospital, Shinshu University, Iida Municipal Hospital, National Hospital Organization Shinshu Ueda Medical Center, Saku General Hospital, Niigata University, Niigata Prefectural Central Hospital, Niigata Municipal Hospital, Nagaoka Red Cross Hospital, Koseiren Takaoka Hospital, Toyama Prefectural Central Hospital, Toyama University, Ishikawa Medical Center for Maternal and Child Health, Kanazawa Medical University, Kanazawa Medical Center, Fukui Prefectural Hospital, Fukui University, Gifu Prefectural General Medical Center, National Hospital Organization Nagara Medical Center, Takayama Red Cross Hospital, Seirei Hamamatsu Hospital, Shizuoka Saiseikai Hospital, Shizuoka Children's Hospital, Hamamatsu Medical University, Numazu Municipal Hospital, Yaizu City Hospital, Fujieda Municipal General Hospital, Nagoya Red Cross Daini Hospital, Nagoya University, Nagoya Red Cross Daiichi Hospital, Toyohashi Municipal Hospital, Nagoya City West Medical Center, Anjo kosei Hospital, Tosei General Hospital, Komaki Municipal Hospital, TOYOTA Memorial Hospital, Okazaki Municipal Hospital, Konan Kosei Hospital, National Mie Central Medical Center, Ise Red Cross Hospital, Yokkaichi Municipal Hospital, Otsu Red Cross Hospital, Shiga University of Medical Science Hospital, Nagahama Red Cross Hospital, Uji Tokushukai Hospital, The Japan Baptist Hospital, Kyoto University, Kyoto Red Cross Daiichi Hospital, National Maizuru Medical Center, Fukuchiyama City Hospital, Kyoto Prefectural University of Medicine Hospital, Kyoto City Hospital, Mitsubishi Kyoto Hospital, Yodogawa Christian Hospital, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka University, Takatsuki General Hospital, Kansai Medical University, Osaka City General Hospital, Osaka City Sumiyoshi Hospital, Aizenbashi Hospital, Toyonaka Municipal Hospital, National Cerebral and Cardiovascular Center, Kitano Hospital, Saiseikai Suita Hospital, Chifune Hospital, Bellland General Hospital, Rinku General Medical Center, Osaka Red Cross Hospital, Yao Municipal Hospital, Osaka General Medical Center, Osaka City University, Hyogo Prefectural Kobe Children's Hospital, Kobe University, Kakogawa West City Hospital, Saiseikai Hyogoken Hospital, Kobe City Medical Center General Hospital, Hyogo College of Medicine Hospital, Himeji Red Cross Hospital, Toyooka Public Hospital, Hyogo Prefectural Awaji Medical Center, Nara Medical University, Wakayama Medical University, Tottori Prefectural Central Hospital, Tottori University, Shimane Prefectural Central Hospital, Matsue Red Cross Hospital, Kurashiki Central Hospital, Tsuyama Central Hospital, Kawasaki Medical School Hospital, National Hospital Organization Okayama Medical Center, Okayama Red Cross Hospital, Hiroshima City Hiroshima Citizens Hospital, Hiroshima Prefectural Hospital, Hiroshima University, Tsuchiya General Hospital, National Hospital Organization Kure Medical Center, Yamaguchi University, Yamaguchi Grand Medical Center, Tokushima University, Tokushima Municipal Hospital, Kagawa University, National Hospital Organization Kagawa Children's Hospital, Matsuyama Red Cross Hospital, Ehime Prefectural Central Hospital, Kochi Health Science Center, St.Mary's Hospital, National Kyushu Medical Center, Kurume University, Kitakyushu Municipal Medical Center, University of Occupational and Environmental Health, Fukuoka University, Kyushu University, Iizuka Hospital, National Hospital Organization Kokura Medical Center, National Hospital Organization Saga Hospital, National Hospital Organization Nagasaki Medical Center, Kumamoto City Hospital, Kumamoto University, Oita Prefectural Hospital, Almeida Memorial Hospital, Nakatsu Municipal Hospital, Miyazaki University, National Hospital Organization Miyakonojo Medical Center, Kagoshima City Hospital, Imakiire General Hospital, Okinawa Prefectural Nanbu Medical Center & Children's Medical Center, Okinawa Prefectural Chubu Hospital, Naha City Hospital, Okinawa Red Cross Hospital. Funding Information: Supported by the Japan Society for the Promotion of Science KAKEN (15K19656 [to H.I.], 15K09717 [to M.O.], and 16K19688 [to J.F.]). The authors declare no conflicts of interest. Publisher Copyright: {\textcopyright} 2017 The Author(s)",

year = "2017",

month = nov,

doi = "10.1016/j.jpeds.2017.05.017",

language = "English",

volume = "190",

pages = "112--117.e3",

journal = "Journal of Pediatrics",

issn = "0022-3476",

publisher = "Mosby Inc.",

}

TY - JOUR

T1 - Early Mortality and Morbidity in Infants with Birth Weight of 500 Grams or Less in Japan

AU - on behalf of the

AU - Neonatal Research Network of Japan (NRNJ) Sapporo City General Hospital

AU - Asahikawa Kosei General Hospital

AU - Engaru-Kosei General Hospital

AU - Kushiro Red Cross Hospital

AU - Obihiro-Kosei General Hospital

AU - Tenshi Hospital

AU - NTT Higashinihon Sapporo Hospital

AU - Nikko Memorial Hospital

AU - Nayoro City General Hospital

AU - Sapporo Medical University

AU - Asahikawa Medical University

AU - Aomori Prefectural Central Hospital

AU - Iwate Medical University

AU - Iwate Prefectural Ofunato Hospital

AU - Iwate Prefectural Kuji Hospital

AU - Iwate Prefectural Ninohe Hospital

AU - Sendai Red Cross Hospital

AU - Akita Red Cross Hospital

AU - Tsuruoka Municipal Shonai Hospital

AU - Yamagata University

AU - Yamagata Prefectural Central Hospital

AU - Fukushima Medical University

AU - Takeda General Hospital

AU - Fukushima National Hospital

AU - Tsukuba University

AU - Tsuchiura Kyodo Hospital

AU - Ibaraki Children's Hospital

AU - Dokkyo Medical University

AU - Jichi Medical University

AU - Ashikaga Red Cross Hospital

AU - Gunma Children's Medical Center

AU - Kiryu Kosei General Hospital

AU - Fuji Heavy Industries Health Insurance Society Ota Memorial Hospital

AU - Gunma University

AU - Saitama Children's Medical Center

AU - Nishisaitama-chuo National Hospital

AU - Saitama Medical University Saitama Medical Center

AU - Kawaguchi Municipal Medical Center

AU - Jichi Medical University Saitama Medical Center

AU - Asahi General Hospital

AU - Chiba Kaihin Municipal Hospital

AU - Kameda Medical Center

AU - Tokyo Women's Medical University Yachiyo Medical Center

AU - Juntendo University Urayasu Hospital

AU - Tokyo Metropolitan Children's Medical Center

AU - Tokyo Women's Medical University

AU - Aiiku Hospital

AU - Nihon University Itabashi Hospital

AU - National Center for Global Health and Medicine

AU - Tokyo Medical University

AU - Teikyo University

AU - Showa University

AU - Japan Red Cross Medical Center

AU - National Center for Child Health and Development

AU - Tokyo Metropolitan Otsuka Hospital

AU - Toho University

AU - Tokyo Metropolitan Bokuto Hospital

AU - Tokyo Jikei Medical University

AU - Tokyo Medical and Dental University

AU - Saint Luku's International Hospital

AU - Juntendo University

AU - Sanikukai Hospital

AU - Katsushika Red Cross Hospital

AU - Yokohama Rosai Hospital

AU - Yokohama City University Medical Center

AU - St. Marianna University School of Medicine Hospital

AU - Kanagawa Children's Medical Center

AU - Tokai University

AU - Kitazato University

AU - Odawara Municipal Hospital

AU - Nippon Medical School Musashi Kosugi Hospital

AU - Saiseikai Yokohamashi Tobu Hospital

AU - National Hospital Organization Yokohama Medical Center

AU - Yamanashi Prefectural Central Hospital

AU - Nagano Children's Hospital

AU - Shinshu University

AU - Iida Municipal Hospital

AU - National Hospital Organization Shinshu Ueda Medical Center

AU - Saku General Hospital

AU - Niigata University

AU - Niigata Prefectural Central Hospital

AU - Niigata Municipal Hospital

AU - Nagaoka Red Cross Hospital

AU - Koseiren Takaoka Hospital

AU - Toyama Prefectural Central Hospital

AU - Toyama University

AU - Ishikawa Medical Center for Maternal and Child Health

AU - Kanazawa Medical University

AU - Kanazawa Medical Center

AU - Fukui Prefectural Hospital

AU - Fukui University

AU - Gifu Prefectural General Medical Center

AU - National Hospital Organization Nagara Medical Center

AU - Takayama Red Cross Hospital

AU - Seirei Hamamatsu Hospital

AU - Shizuoka Saiseikai Hospital

AU - Shizuoka Children's Hospital

AU - Hamamatsu Medical University

AU - Numazu Municipal Hospital

AU - Yaizu City Hospital

AU - Fujieda Municipal General Hospital

AU - Nagoya Red Cross Daini Hospital

AU - Nagoya University

AU - Nagoya Red Cross Daiichi Hospital

AU - Toyohashi Municipal Hospital

AU - Nagoya City West Medical Center

AU - Anjo Kosei Hospital

AU - Tosei General Hospital

AU - Komaki Municipal Hospital

AU - TOYOTA Memorial Hospital

AU - Okazaki Municipal Hospital

AU - Konan Kosei Hospital

AU - National Mie Central Medical Center

AU - Ise Red Cross Hospital

AU - Yokkaichi Municipal Hospital

AU - Otsu Red Cross Hospital

AU - Shiga University of Medical Science Hospital

AU - Nagahama Red Cross Hospital

AU - Uji Tokushukai Hospital

AU - The Japan Baptist Hospital

AU - Kyoto University

AU - Kyoto Red Cross Daiichi Hospital

AU - National Maizuru Medical Center

AU - Fukuchiyama City Hospital

AU - Kyoto Prefectural University of Medicine Hospital

AU - Kyoto City Hospital

AU - Mitsubishi Kyoto Hospital

AU - Yodogawa Christian Hospital

AU - Osaka Medical Center and Research Institute for Maternal and Child Health

AU - Osaka University

AU - Takatsuki General Hospital

AU - Kansai Medical University

AU - Osaka City General Hospital

AU - Osaka City Sumiyoshi Hospital

AU - Aizenbashi Hospital

AU - Toyonaka Municipal Hospital

AU - National Cerebral and Cardiovascular Center, Kitano Hospital

AU - Saiseikai Suita Hospital

AU - Chifune Hospital

AU - Bellland General Hospital

AU - Rinku General Medical Center

AU - Osaka Red Cross Hospital

AU - Yao Municipal Hospital

AU - Osaka General Medical Center

AU - Osaka City University

AU - Hyogo Prefectural Kobe Children's Hospital

AU - Kobe University

AU - Kakogawa West City Hospital

AU - Saiseikai Hyogoken Hospital

AU - Kobe City Medical Center General Hospital

AU - Hyogo College of Medicine Hospital

AU - Himeji Red Cross Hospital

AU - Toyooka Public Hospital

AU - Hyogo Prefectural Awaji Medical Center

AU - Nara Medical University

AU - Wakayama Medical University

AU - Tottori Prefectural Central Hospital

AU - Tottori University

AU - Shimane Prefectural Central Hospital

AU - Matsue Red Cross Hospital

AU - Kurashiki Central Hospital

AU - Tsuyama Central Hospital

AU - Kawasaki Medical School Hospital

AU - National Hospital Organization Okayama Medical Center

AU - Okayama Red Cross Hospital

AU - Hiroshima City Hiroshima Citizens Hospital

AU - Hiroshima Prefectural Hospital

AU - Hiroshima University

AU - Tsuchiya General Hospital

AU - National Hospital Organization Kure Medical Center

AU - Yamaguchi University

AU - Yamaguchi Grand Medical Center

AU - Tokushima University

AU - Tokushima Municipal Hospital

AU - Kagawa University

AU - National Hospital Organization Kagawa Children's Hospital

AU - Matsuyama Red Cross Hospital

AU - Ehime Prefectural Central Hospital

AU - Kochi Health Science Center

AU - St.Mary's Hospital

AU - National Kyushu Medical Center

AU - Kurume University

AU - Kitakyushu Municipal Medical Center

AU - University of Occupational and Environmental Health

AU - Fukuoka University

AU - Kyushu University

AU - Iizuka Hospital

AU - National Hospital Organization Kokura Medical Center

AU - National Hospital Organization Saga Hospital

AU - National Hospital Organization Nagasaki Medical Center

AU - Kumamoto City Hospital

AU - Kumamoto University

AU - Oita Prefectural Hospital

AU - Almeida Memorial Hospital

AU - Nakatsu Municipal Hospital

AU - Miyazaki University

AU - National Hospital Organization Miyakonojo Medical Center

AU - Kagoshima City Hospital

AU - Imakiire General Hospital

AU - Okinawa Prefectural Nanbu Medical Center & Children's Medical Center

AU - Okinawa Prefectural Chubu Hospital

AU - Naha City Hospital

AU - Okinawa Red Cross Hospital

AU - Inoue, Hirosuke

AU - Ochiai, Masayuki

AU - Yasuoka, Kazuaki

AU - Tanaka, Koichi

AU - Kurata, Hiroaki

AU - Fujiyoshi, Junko

AU - Matsushita, Yuki

AU - Suga, Shutaro

AU - Nonaka, Kazuaki

AU - Taguchi, Tomoaki

AU - Kato, Kiyoko

AU - Ohga, Shouichi

N1 - Funding Information: Institutions enrolled in the study of the Neonatal Research Network, Japan, include: Sapporo City General Hospital, Asahikawa Kosei General Hospital, Engaru-Kosei General Hospital, Kushiro Red Cross Hospital, Obihiro-Kosei General Hospital, Tenshi Hospital, NTT Higashinihon Sapporo Hospital, Nikko Memorial Hospital, Nayoro City General Hospital, Sapporo Medical University, Asahikawa Medical University, Aomori Prefectural Central Hospital, Iwate Medical University, Iwate Prefectural Ofunato Hospital, Iwate Prefectural Kuji Hospital, Iwate Prefectural Ninohe Hospital, Sendai Red Cross Hospital, Akita Red Cross Hospital, Tsuruoka Municipal Shonai Hospital, Yamagata University, Yamagata Prefectural Central Hospital, Fukushima Medical University, Takeda General Hospital, Fukushima National Hospital, Tsukuba University, Tsuchiura Kyodo Hospital, Ibaraki Children's Hospital, Dokkyo Medical University, Jichi Medical University, Ashikaga Red Cross Hospital, Gunma Children's Medical Center, Kiryu Kosei General Hospital, Fuji Heavy Industries Health Insurance Society Ota Memorial Hospital, Gunma University, Saitama Children's Medical Center, Nishisaitama-chuo National Hospital, Saitama Medical University Saitama Medical Center, Kawaguchi Municipal Medical Center, Jichi Medical University Saitama Medical Center, Asahi General Hospital, Chiba Kaihin Municipal Hospital, Kameda Medical Center, Tokyo Women's Medical University Yachiyo Medical Center, Juntendo University Urayasu Hospital, Tokyo Metropolitan Children's Medical Center, Tokyo Women's Medical University, Aiiku Hospital, Nihon University Itabashi Hospital, National Center for Global Health and Medicine, Tokyo Medical University, Teikyo University, Showa University, Japan Red Cross Medical Center, National Center for Child Health and Development, Tokyo Metropolitan Otsuka Hospital, Toho University, Tokyo Metropolitan Bokuto Hospital, Tokyo Jikei Medical University, Tokyo Medical and Dental University, Saint Luku's International Hospital, Juntendo University, Sanikukai Hospital, Katsushika Red Cross Hospital, Yokohama Rosai Hospital, Yokohama City University Medical Center, St. Marianna University School of Medicine Hospital, Kanagawa Children's Medical Center, Tokai University, Kitazato University, Odawara Municipal Hospital, Nippon Medical School Musashi Kosugi Hospital, Saiseikai Yokohamashi Tobu Hospital, National Hospital Organization Yokohama Medical Center, Yamanashi Prefectural Central Hospital, Nagano Children's Hospital, Shinshu University, Iida Municipal Hospital, National Hospital Organization Shinshu Ueda Medical Center, Saku General Hospital, Niigata University, Niigata Prefectural Central Hospital, Niigata Municipal Hospital, Nagaoka Red Cross Hospital, Koseiren Takaoka Hospital, Toyama Prefectural Central Hospital, Toyama University, Ishikawa Medical Center for Maternal and Child Health, Kanazawa Medical University, Kanazawa Medical Center, Fukui Prefectural Hospital, Fukui University, Gifu Prefectural General Medical Center, National Hospital Organization Nagara Medical Center, Takayama Red Cross Hospital, Seirei Hamamatsu Hospital, Shizuoka Saiseikai Hospital, Shizuoka Children's Hospital, Hamamatsu Medical University, Numazu Municipal Hospital, Yaizu City Hospital, Fujieda Municipal General Hospital, Nagoya Red Cross Daini Hospital, Nagoya University, Nagoya Red Cross Daiichi Hospital, Toyohashi Municipal Hospital, Nagoya City West Medical Center, Anjo kosei Hospital, Tosei General Hospital, Komaki Municipal Hospital, TOYOTA Memorial Hospital, Okazaki Municipal Hospital, Konan Kosei Hospital, National Mie Central Medical Center, Ise Red Cross Hospital, Yokkaichi Municipal Hospital, Otsu Red Cross Hospital, Shiga University of Medical Science Hospital, Nagahama Red Cross Hospital, Uji Tokushukai Hospital, The Japan Baptist Hospital, Kyoto University, Kyoto Red Cross Daiichi Hospital, National Maizuru Medical Center, Fukuchiyama City Hospital, Kyoto Prefectural University of Medicine Hospital, Kyoto City Hospital, Mitsubishi Kyoto Hospital, Yodogawa Christian Hospital, Osaka Medical Center and Research Institute for Maternal and Child Health, Osaka University, Takatsuki General Hospital, Kansai Medical University, Osaka City General Hospital, Osaka City Sumiyoshi Hospital, Aizenbashi Hospital, Toyonaka Municipal Hospital, National Cerebral and Cardiovascular Center, Kitano Hospital, Saiseikai Suita Hospital, Chifune Hospital, Bellland General Hospital, Rinku General Medical Center, Osaka Red Cross Hospital, Yao Municipal Hospital, Osaka General Medical Center, Osaka City University, Hyogo Prefectural Kobe Children's Hospital, Kobe University, Kakogawa West City Hospital, Saiseikai Hyogoken Hospital, Kobe City Medical Center General Hospital, Hyogo College of Medicine Hospital, Himeji Red Cross Hospital, Toyooka Public Hospital, Hyogo Prefectural Awaji Medical Center, Nara Medical University, Wakayama Medical University, Tottori Prefectural Central Hospital, Tottori University, Shimane Prefectural Central Hospital, Matsue Red Cross Hospital, Kurashiki Central Hospital, Tsuyama Central Hospital, Kawasaki Medical School Hospital, National Hospital Organization Okayama Medical Center, Okayama Red Cross Hospital, Hiroshima City Hiroshima Citizens Hospital, Hiroshima Prefectural Hospital, Hiroshima University, Tsuchiya General Hospital, National Hospital Organization Kure Medical Center, Yamaguchi University, Yamaguchi Grand Medical Center, Tokushima University, Tokushima Municipal Hospital, Kagawa University, National Hospital Organization Kagawa Children's Hospital, Matsuyama Red Cross Hospital, Ehime Prefectural Central Hospital, Kochi Health Science Center, St.Mary's Hospital, National Kyushu Medical Center, Kurume University, Kitakyushu Municipal Medical Center, University of Occupational and Environmental Health, Fukuoka University, Kyushu University, Iizuka Hospital, National Hospital Organization Kokura Medical Center, National Hospital Organization Saga Hospital, National Hospital Organization Nagasaki Medical Center, Kumamoto City Hospital, Kumamoto University, Oita Prefectural Hospital, Almeida Memorial Hospital, Nakatsu Municipal Hospital, Miyazaki University, National Hospital Organization Miyakonojo Medical Center, Kagoshima City Hospital, Imakiire General Hospital, Okinawa Prefectural Nanbu Medical Center & Children's Medical Center, Okinawa Prefectural Chubu Hospital, Naha City Hospital, Okinawa Red Cross Hospital. Funding Information: Supported by the Japan Society for the Promotion of Science KAKEN (15K19656 [to H.I.], 15K09717 [to M.O.], and 16K19688 [to J.F.]). The authors declare no conflicts of interest. Publisher Copyright: © 2017 The Author(s)

PY - 2017/11

Y1 - 2017/11

N2 - Objective To assess the short-term prognosis of Japanese infants with a birth weight (BW) of ≤500 g. Study design Demographic and clinical data were reviewed for 1473 live born infants with a BW ≤500 g at gestational age ≥22 weeks who were treated in the 204 affiliated hospitals of the Neonatal Research Network of Japan between 2003 and 2012. Results Survival to hospital discharge occurred in 811 of 1473 infants (55%; 95% CI 53%-58%). The survival rates of BW ≤300 g, 301-400 g, and 401-500 g were 18% (95% CI 10%-31%), 41% (95% CI 36%-47%), and 60% (95% CI 57%-63%), respectively. In a multivariable Cox proportional hazards analysis, antenatal corticosteroid use (adjusted hazard ratio: 0.68; 95% CI 0.58-0.81; P <.01), cesarean delivery (0.69; 95% CI 0.56-0.85; P <.01), advanced gestational age per week (0.94; 95% CI 0.89-0.99; P =.02), BW per 100-g increase (0.55; 95% CI 0.49-0.64; P <.01), Apgar score ≥4 at 5 minutes (0.51; 95% CI 0.43-0.61; P <.01), and no major congenital abnormalities (0.38; 95% CI 0.29-0.51; P <.01) were associated with survival to discharge. Despite the improved survival rate over the 10-year study period (from 40% in 2003 [95% CI 30%-51%] to 68% in 2012 [95% CI 61%-75%]), at least 1 severe morbidity was present in 81%-89% of the survivors. Conclusions Improvements in perinatal-neonatal medicine have improved the survival, but not the rate of major morbidities, of infants with a BW ≤500 g in Japan.

AB - Objective To assess the short-term prognosis of Japanese infants with a birth weight (BW) of ≤500 g. Study design Demographic and clinical data were reviewed for 1473 live born infants with a BW ≤500 g at gestational age ≥22 weeks who were treated in the 204 affiliated hospitals of the Neonatal Research Network of Japan between 2003 and 2012. Results Survival to hospital discharge occurred in 811 of 1473 infants (55%; 95% CI 53%-58%). The survival rates of BW ≤300 g, 301-400 g, and 401-500 g were 18% (95% CI 10%-31%), 41% (95% CI 36%-47%), and 60% (95% CI 57%-63%), respectively. In a multivariable Cox proportional hazards analysis, antenatal corticosteroid use (adjusted hazard ratio: 0.68; 95% CI 0.58-0.81; P <.01), cesarean delivery (0.69; 95% CI 0.56-0.85; P <.01), advanced gestational age per week (0.94; 95% CI 0.89-0.99; P =.02), BW per 100-g increase (0.55; 95% CI 0.49-0.64; P <.01), Apgar score ≥4 at 5 minutes (0.51; 95% CI 0.43-0.61; P <.01), and no major congenital abnormalities (0.38; 95% CI 0.29-0.51; P <.01) were associated with survival to discharge. Despite the improved survival rate over the 10-year study period (from 40% in 2003 [95% CI 30%-51%] to 68% in 2012 [95% CI 61%-75%]), at least 1 severe morbidity was present in 81%-89% of the survivors. Conclusions Improvements in perinatal-neonatal medicine have improved the survival, but not the rate of major morbidities, of infants with a BW ≤500 g in Japan.

UR - http://www.scopus.com/inward/record.url?scp=85020111028&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85020111028&partnerID=8YFLogxK

U2 - 10.1016/j.jpeds.2017.05.017

DO - 10.1016/j.jpeds.2017.05.017

M3 - Article

C2 - 28746032

AN - SCOPUS:85020111028

SN - 0022-3476

VL - 190

SP - 112-117.e3

JO - Journal of Pediatrics

JF - Journal of Pediatrics

ER -

Early Mortality and Morbidity in Infants with Birth Weight of 500 Grams or Less in Japan

Abstract

All Science Journal Classification (ASJC) codes

Access to Document

Other files and links

Fingerprint

Cite this