Impact of age at diagnosis on long-term prognosis in patients with intestinal Behçet's disease.

BACKGROUND AND AIM: Although age at disease onset is considered to be a significant factor in the prognosis of Crohn's disease, little is known about its influence on the long-term prognosis of those with intestinal Behçet's disease (BD). This study aimed to evaluate the long-term clinical outcomes of patients with intestinal BD according to age of disease onset. METHODS: Patients diagnosed with intestinal BD at < 18, 18-60, and > 60 years of age were classified into early-onset, adult-onset, and late-onset groups, respectively. The influence of disease onset time on clinical prognosis, including specific medical requirements, BD-related intestinal surgery, hospitalization, and emergency room visits, was compared using the log-rank test in a large cohort of patients with intestinal BD. RESULTS: Among 780 patients, 21 (2.7%), 672 (86.2%), and 87 (11.1%) comprised the early-onset, adult-onset, and late-onset groups, respectively. Patients in the early-onset group were more likely to require immunosuppressants than those in the adult-onset group (P = 0.048). Nine (42.9%), 158 (23.5%), and 18 (20.7%) patients in the early-onset, adult-onset, and late-onset groups, respectively, underwent intestinal resection. The early-onset group exhibited a higher risk for intestinal resection than the late-onset (P = 0.043) and adult-onset (P = 0.030) groups. The late-onset group exhibited a higher risk for BD-related hospitalization than the adult-onset group (P = 0.023). CONCLUSIONS: Age at diagnosis affected the clinical course of intestinal BD, including intestinal surgery, hospitalization, and specific medical requirements. Different treatment strategies should be established according to age at diagnosis.

APP96-110 Elicits Neuroprotective Effects Following Ischemic Insult in Animal Models.

Competitive amyloidogenic pathways play an important role in many neurological diseases such as the onset of various degenerative diseases and ischemic stroke. Overexpression of amyloid precursor protein (APP) and amyloid-beta is modulated via the amyloidogenic pathway, which plays a crucial role in neuroinflammation. During ischemic conditions, the activity of the anti-inflammatory non-amyloidogenic pathway decreases, thus increasing the activity of amyloidogenic pathway. The soluble alpha form of APP (sAPPα), formed via the non-amyloidogenic pathway, exhibits neuroprotective effects against neurological diseases. sAPPα is thought to have a modulatory effect on several cell survival pathways, including its ability to inhibit the phosphoinositide 3-kinases (PI3K) pathway, thereby inhibiting the inflammatory response. The APP derivative, APP96-110, could act as a functional substitute for native sAPPα. Herein, we investigated whether APP96-110 has neuroprotective effects against neuroinflammation and damage following cerebral ischemic stroke. Treatment with diluted APP96-110 (0.005 mg/kg) in mice after 30 min of transient middle cerebral artery occlusion (tMCAO) showed improved motor function and reduced expression of the inflammatory marker CD86. APP96-110 decreased the infarct size and induced an anti-inflammatory response by inhibiting the PI3K pathway. These results suggest that the treatment of APP96-110 is efficacious in reducing neuroinflammation and infarct size in ischemic stroke.

Genotype-based Treatment With Thiopurine Reduces Incidence of Myelosuppression in Patients With Inflammatory Bowel Diseases.

BACKGROUND & AIMS: Thiopurine-related myelosuppression (most frequently leukopenia) interferes with thiopurine therapy for patients with inflammatory bowel diseases (IBD). We investigated whether pretreatment analyses genetic variants associated with thiopurine-induced leukopenia could be used to effectively identify patients who required dose adjustments. METHODS: We performed a multicenter, prospective study of patients with IBD at 5 tertiary medical centers in Korea, from January 2016 through September 2018. Seventy-two patients were randomly assigned to a group that underwent genotype analysis for the NUDT15 variant (rs116855232) and FTO variant (rs79206939) and 3 common TPMT variants (rs1800460, rs1800462, rs1142345) associated with myelosuppression and 92 patients were assigned to a group that did not undergo genotype analysis (non-genotyping group). Patients heterozygous for any variant received 50 mg azathioprine equivalents, whereas those who were homozygous for any variant received alternative drugs. Patients who did not carry any of the genetic variants and patients in the non-genotyping group received 50 mg azathioprine equivalents followed by dose escalation up to 2-2.5 mg/kg. Myelosuppression was defined as white blood cell counts below 3000/µL, levels of hemoglobin 10 g/dL, or platelet counts below 100 K/µL. RESULTS: Twelve patients (16.7%) in the genotype analysis group and 33 patients (35.9%) in the non-genotyping group developed myelosuppression (P=.005). A multivariate analysis revealed that body mass indices above 21 kg/m2 (hazard ratio [HR], 0.43; 95% CI, 0.22-0.81; P = .009), pretreatment genotype analysis (HR, 0.37; 95% CI, 0.18-0.77; P = .008), and the maximum dose of thiopurines (HR, 0.34; 95% CI, 0.19-0.59; P < .001) independently decreased risk of myelosuppression. Pretreatment genotype analysis reduced numbers of outpatient clinic visit and numbers of patients with drug discontinuation or dose reductions. CONCLUSIONS: In a randomized controlled study of patients undergoing thiopurine therapy for IBD, we found that selection of therapy based on genetic variants associated with thiopurine-induced leukopenia significantly reduced the proportion of patients with myelosuppression during treatment. ClinicalTrials.gov no: NCT03719118.

Designing Internal Hierarchical Porous Networks in Polymer Monoliths that Exhibit Rapid Removal and Photocatalytic Degradation of Aromatic Pollutants.

This paper describes the preparation of 3D polymer monoliths containing internal hierarchical porosity. The porous networks are fabricated based on Pickering high-internal-phase emulsions (HIPEs) stabilized by microporous ß-cyclodextrin-based polymer particles (CDPs) as the emulsifier; CDPs are facilely synthesized by the polyaddition reactions without the need for catalysts. The designed Pickering agents enable to form a bicontinuous internal phase in 8:2 cyclohexane-water v/v, and the oil droplets in the continuous water phase is found to be fairly stable up to 1 month. Furthermore, the addition of acrylamide and N,N'-methylenebis(acrylamide) results in polymer networks after in situ thermal polymerization at 60 °C in the water phase, and the monoliths include both interconnected macropores from the HIPE template and micro- and mesopores from the CDPs embedded at the interface. The porous monoliths rapidly absorb a variety of solvents taking advantage of multiscale porosity and amphiphilicity. Furthermore, the materials can be efficiently used for the removal of aromatic pollutants and then reused after washing and drying without the deterioration of performance. Also, they exhibit high photocatalytic capability and good recyclability as being used as a catalytic support when embedded with titanium dioxide (TiO2 ).

Thiopurine Therapy in Patients With Inflammatory Bowel Disease: A Focus on Metabolism and Pharmacogenetics.

Thiopurines have been widely used for the maintenance of remission or steroid sparing in patients with inflammatory bowel disease. However, potential drug-related adverse events frequently interfere with their use. Indeed, drug withdrawals associated with adverse reactions have been reported in approximately 25% of patients. To balance the efficacy, safety, and tolerability of thiopurines, regular monitoring of biomarkers (complete blood cell count, liver function test, and metabolic profiles), steady dose escalation, and pretreatment thiopurine S-methyltransferase (TPMT) genotype screening have been routinely recommended. However, the complex thiopurine metabolic pathway and individual differences attributed to pharmacogenetic diversity limit the effectiveness of these strategies in the optimization of thiopurine therapy. Recently, in an effort to facilitate more accurate and personalized prediction of thiopurine response or toxicity, novel genetic markers including NUDT15 and FTO genes were discovered. These discoveries are remarkable because TPMT screening has minimal efficacy for predicting myelosuppression especially in Asian populations, despite the fact that thee populations have a higher frequency of myelosuppression than Western populations. This review focuses on the current understanding of the metabolic pathway and the pharmacogenetics of thiopurines and suggests a personalized preventive strategy against potential adverse drug reactions to optimize their therapeutic application.

Pickering Emulsion Stabilized by Microporous Organic Polymer Particles for the Fabrication of a Hierarchically Porous Monolith.

A hierarchically porous monolith comprising the melamine-based microporous organic polymer (MOP) particles was prepared by the Pickering emulsion templating method. The MOP particles were synthesized by polycondensation of melamine and terephthaldicarboxaldehyde. Because of the balanced presence of hydrophilic nitrogen containing groups and hydrophobic benzene rings, the MOP particles showed good amphiphilicity. A Pickering emulsion was prepared, where cyclohexane droplets with an average size of about 25 µm were stabilized by the MOP particles (3.4 wt %) in an aqueous continuous phase. The cyclohexane internal phase fraction was slightly higher than 60%. The emulsion showed no phase separation even after two weeks. The Pickering emulsion containing a small amount of polyvinyl alcohol (1 wt %) in a continuous phase as a reinforcement was used as a template for the fabrication of a monolith of the MOP particles. The Pickering emulsion was freeze-dried to produce a hierarchically porous monolith. The MOP monolith possessed macropores templated by the oil droplets and micro- and mesopores in the MOP particles that constituted the macropore walls. The MOP monolith exhibited a high dye absorption ability in a solution of RhB in chloroform and a good absorption capacity for nonpolar organic solvents. After the absorption, the monolith could be regenerated by solvent exchange with cyclohexane and subsequent freeze-drying.

Does Medical Acceleration Improve Outcomes in Ulcerative Colitis Patients Who Are in Clinical Remission but Have Endoscopic Inflammation?

BACKGROUND: Discrepancies between clinical symptoms and mucosal inflammation have been reported in up to 50% of patients with ulcerative colitis (UC). However, there are no guidelines and only limited information for appropriate treatment manipulation. AIM: We aimed to evaluate long-term outcomes according to treatment strategies and determine predictive factors for disease relapse in UC patients who are in clinical remission (CR) but still have endoscopic inflammation. METHODS: A total of 204 patients who were confirmed as achieving CR but still had mucosal inflammation were included. CR was defined as "partial Mayo score ≤ 1" with no changes in medications or use of any corticosteroids during the past 3 months. An active mucosal lesion was defined as "endoscopic Mayo subscore > 0." RESULTS: The mean patient age was 43.5 years, and 53.9% were male. The mean disease duration was 89.9 months. During a mean follow-up of 34 months, 90 patients (44%) experienced disease relapse. The cumulative relapse-free rate did not differ by treatment strategy (maintenance of current therapy vs. dose elevation or step-up therapy). Multivariate analysis revealed that left-side colitis or pancolitis at diagnosis (OR 2.10; 95% CI 1.04-4.27; P = 0.040) and number of extraintestinal manifestations ≥ 2 (OR 5.62; 95% CI 1.10-28.68; P = 0.038) were independent predictive factors for disease relapse. CONCLUSIONS: The current medical acceleration treatment strategy did not have a significant influence on the long-term outcomes of UC patients in CR but with active mucosal inflammation. Disease extent at diagnosis and extraintestinal manifestations were independently predictive of disease relapse.

Triple therapy versus sequential therapy for the first-line Helicobacter pylori eradication.

BACKGROUND: The eradication rate of Helicobacter pylori (H. pylori) with triple therapy which was considered as standard first-line treatment has decreased to 70-85%. The aim of this study is to compare 7-day triple therapy versus 10-day sequential therapy as the first line treatment. METHODS: Data of 1240 H. pylori positive patients treated with triple therapy or sequential therapy from January 2013 to December 2015 were analyzed retrospectively. The patients who had undertaken previous H. pylori eradication therapy or gastric surgery were excluded. RESULTS: There were 872 (74.3%) patients in the triple therapy group, and 302 (25.7%) patients in the sequential therapy group. There was no significant difference between the two groups regarding age, residence, comorbidities or drug compliance, but several differences were noted in endoscopic characteristics and indication for the treatment. The eradication rate of H. pylori by intention to treat analysis was 64.3% in the triple therapy group, and 81.9% in the sequential therapy group (P = 0.001). In per protocol analysis, H. pylori eradication rate in the triple therapy and sequential therapy group was 81.9 and 90.3%, respectively (P = 0.002). There was no significant difference in overall adverse events between the two groups (P = 0.706). For the rescue therapy, bismuth-containing quadruple therapy showed comparable treatment efficacy after sequential therapy, as following triple therapy. CONCLUSIONS: The eradication rate of triple therapy was below the recommended threshold. Sequential therapy could be effective and tolerable candidate for the first-line H. pylori eradication therapy.

Clinical Features and Outcomes of Respiratory Complications in Patients with Thoracic Hyperkyphosis.

INTRODUCTION: There are few data about thoracic hyperkyphosis which focused on respiratory events and prognoses. We investigated the clinical features and outcomes of respiratory complications requiring hospitalization in patients with thoracic hyperkyphosis. METHODS: Following a retrospective review of the medical records between 2002 and 2011, we included 51 patients with thoracic hyperkyphosis who had visited the respiratory department due to respiratory symptoms. RESULTS: Of total 51 patients, 35 patients were hospitalized due to respiratory events. Among 56 total hospitalized events, acute respiratory failure (ARF) (n = 18) and exacerbation of a chronic airway disorder (n = 18) were the most common causes. Respiratory events related mortality was 13.7 % (7/51). The median value of the thoracic kyphosis angle was 89.0°. The ratio of the measured kyphosis angle to the normal value according to age and sex showed the median value of 2.38 (interquartile range 1.61-2.87). This ratio was negatively correlated with both predicted forced vital capacity (γ = -0.647, p < 0.0001) and predicted forced expiratory volume for 1 s (γ = -0.518, p = 0.008). After adjustments for age and sex, hyperkyphosis (angle ≥90°) was not found to influence the development of ARF (hazard ratio 3.2; 95 % confidence interval, 0.86-12.14; p = 0.082). CONCLUSIONS: Patients with thoracic hyperkyphosis presenting to a respiratory department with respiratory issues commonly experienced respiratory events requiring hospitalization and had a poor prognosis. In addition, the severity of the kyphosis angle was correlated with respiratory insufficiency although it was not a risk factor for the development of ARF.

Reversible thermochromic polymer film embedded with fluorescent organogel nanofibers.

We report a reversible thermochromic nanocomposite polymer film composed of fluorescent organogel fibers and a highly cross-linked polymer matrix. A series of cyano-substituted oligo(p-phenylenevinylene) (CN-OPV) derivatives were synthesized by the reaction of dialdehydes with phenyl or naphthyl acetonitrile under basic conditions. Among the CN-OPV derivatives, NA-DBA having naphtyl moieties and dodecyloxy chains formed a stable organogel in a cross-linkable monomeric solvent (ethylene glycol dimethacrylate). The organogel showed a thermoreversible sol-gel transition, accompanying the emission color change. A nanocomposite polymer film obtained by photopolymerization of the organogel between two quartz plates also exhibited reversible thermochromism. Under 365 nm irradiation, the orange color of the film at 25 °C became yellowish green at 120 °C. The fluorescence spectroscopy, DSC, and microscopy results determined that the thermally reversible self-assembly of NA-DBA occurred in the polymer matrix, resulting in reversible thermochromism. The melted gelator molecules at 120 °C did not diffuse into the polymer matrix probably because of poor interactions of the gelator molecules with the polymer matrix. The NA-DBA molecules dispersed in poly(methyl methacrylate), without forming a supramolecular structure, did not show thermochromism.

Coexistence of helical morphologies in columnar stacks of star-shaped discotic hydrazones.

Discotic hydrazone molecules are of particular interest as they form discotic phases where the discs are rigidified by intramolecular hydrogen bonds. Here, we investigate the thermotropic behavior and solid-state organizations of three discotic hydrazone derivatives with dendritic groups attached to their outer peripheries, containing six, eight, and ten carbons of linear alkoxy chains. On the basis of two-dimensional wide angle X-ray scattering (2DWAXS), the elevated temperature liquid crystalline (LC) phases were assigned to a hexagonal columnar (Colh) organization with nontilted hydrazone discs for all three compounds. With WAXS, advanced solid-state nuclear magnetic resonance (SSNMR) techniques, and ab initio computations, the compounds with six and ten carbons of achiral alkoxy side chains were further subjected to studies at 25 °C, revealing complex crystalline phases with rigid columns and flexible side chains. This combined approach led to models of coexisting helical columnar stacking morphologies for both systems with two different tilt/pitch angles between successive hydrazone molecules. The differences in tilt/pitch angles between the two compounds illustrate that the columns with short alkoxy chains (six carbons) are more influenced by the presence of other stacks in their vicinity, while those with long side chains are less tilted due to a larger alkoxy (ten carbons) buffer zone. The formation of different packing morphologies in the crystalline phase of a columnar LC has rarely been reported so far, which suggests the possibility of complex stacking structures of similar organic LC systems, utilizing small molecules as potential materials for applications in organic electronics.

Serum cystatin C during 30 postnatal days is dependent on the postconceptional age in neonates.

BACKGROUND: Cystatin C (CysC) is a promising endogenous marker for renal function. However, the reference serum CysC level is not sufficiently studied in neonates. This study was conducted to investigate the reference level of serum CysC for neonates, including very low birth weight infants according to the postconceptional age (PCA). METHODS: Serum CysC levels were measured in 883 blood samples (246 neonates including 127 premature infants). Infants with symptoms or signs of acute kidney injury, systemic illness, congenital anomaly, or renal pathology were excluded. CysC levels were analyzed for association between subgroups dichotomized by postnatal age and PCA. RESULTS: Reference ranges of serum CysC were determined and a decreasing trend of CysC levels was observed as PCA increased, except for the first 3 postnatal days. CysC levels were negatively correlated with gestational age at birth, and PCA (P < 0.001), while positively correlated with postnatal age and serum creatinine (P < 0.001). CONCLUSION: The reference level of serum CysC was determined according to postnatal age and PCA. As the reference CysC level was dependent on gestational age and PCA, consideration of these parameters is warranted when assessing CysC levels in neonates.

Development of functional gastrointestinal disorder symptoms following laparoscopic cholecystectomy: a prospective cohort study.

Background: The casual relationship between the role of cholecystectomy and functional gastrointestinal disorders (FGIDs) are a controversial clinical challenge. This study aimed to investigate: (1) the overlap of FGIDs before cholecystectomy and its long-term outcome after surgery in patients with symptomatic cholelithiasis, and (2) the incidence of new-onset FGIDs after cholecystectomy. Methods: Patients with symptomatic gallstone disease who underwent elective, laparoscopic cholecystectomy were prospectively enrolled. Healthy populations who underwent medical check-ups were selected as age- and sex-matched controls. Questionnaires regarding sociodemographic characteristics, gastrointestinal symptoms and a somatization symptom checklist (SSC) were completed at baseline and 12 months thereafter. Results: The prevalence of all FGID symptoms before cholecystectomy were significantly higher in the group of patients with symptomatic cholecystolithiasis compared to the control group. In cholecystectomy group, the preoperative FGID symptoms improved after surgery, except for chronic diarrhea. Compared to the controls, the new-onset FGIDs, including functional dyspepsia (14.8% vs. 6.9%; p = 0.040), functional diarrhea (6.6% vs. 0.2%; p < 0.001), and chronic abdominal pain (11.9% vs. 4.4%; p = 0.024), were more common at 1 year after cholecystectomy. Somatization was independent predictors of new-onset dyspepsia and abdominal pain, while newly occurring diarrhea was not realted to somatization. Conclusion: Overlap of FGIDs was common in patients with symptomatic cholelithiasis before surgery and at follow-up 1 year after cholecystectomy. Furthermore, new-onset FGIDs could be occurred after cholecystectomy. Therefore, a delicate diagnostic approaches and appropriate treatments about co-existent FGIDs should be given in patients with cholelithiasis before and after cholecystectomy.

Diagnosis and management of acute colonic diverticulitis: results of a survey among Korean gastroenterologists.

BACKGROUND/AIMS: Some management strategies for acute colonic diverticulitis remain controversial in Korean real-world practice because their clinical features differ from those in the West. This study aimed to investigate the opinions of Korean physicians regarding the diagnosis and treatment of acute diverticulitis. METHODS: A web-based survey was conducted among gastroenterologists specializing on treating lower gastrointestinal disorders. The questionnaires concerned overall management strategies for colonic diverticulitis, including diagnosis, treatment, and follow-up. RESULTS: In total, 209 gastroenterologists responded to the survey. Less than one-fourth of the respondents (23.6%) answered that left-sided colonic diverticulitis is more likely to be complicated than right-sided colonic diverticulitis. Most respondents agreed that immunocompromised patients with diverticulitis have worse clinical outcomes than immunocompetent patients (71.3%). Computed tomography was the most preferred tool for diagnosing diverticulitis (93.9%). Approximately 89% of the respondents answered that they believed antibiotic treatment is necessary to treat acute uncomplicated diverticulitis. Most respondents (92.6%) agreed that emergency surgery is not required for diverticulitis with an abscess or microperforation without panperitonitis. Further, 94.7% of the respondents agreed that colon cancer screening is necessary in patients aged ≥ 50 years with diverticulitis after they have recovered from acute illness. Many respondents (71.4%) agreed that surgery for recurrent diverticulitis should be individualized. CONCLUSION: Opinions regarding management strategies for colonic diverticulitis among Korean gastroenterologists were well agreed upon in some areas but did not agree well in other areas. Evidence-based guidelines that meet the practical needs of the Korean population should be developed.

Comparative outcomes of acute colonic diverticulitis in immunocompromised versus immunocompetent patients: a systematic review and meta-analysis.

BACKGROUND/AIMS: Immunocompromised patients with acute colonic diverticulitis are at high risk for complications and failure of non-surgical treatment. However, evidence on the comparative outcomes of immunocompromised and immunocompetent patients with diverticulitis is lacking. This systematic review and meta-analysis investigated the outcomes of medical treatment in immunocompromised and immunocompetent patients with diverticulitis. METHODS: A comprehensive literature search was conducted in PubMed, Embase, and the Cochrane Library. Studies comparing the clinical outcomes of immunocompromised and immunocompetent patients with diverticulitis were included. RESULTS: A total of 10 studies with 1,946,461 subjects were included in the quantitative synthesis. The risk of emergency surgery and postoperative mortality after emergency surgery was significantly higher in immunocompromised patients than in immunocompetent patients with diverticulitis (risk ratio [RR], 1.76; 95% confidence interval [CI], 1.31-2.38 and RR, 3.05; 95% CI, 1.70-5.45, respectively). Overall risk of complications associated with diverticulitis was non-significantly higher in immunocompromised than in immunocompetent patients (RR, 1.24; 95% CI, 0.95-1.63). Overall mortality irrespective of surgery was significantly higher in immunocompromised than in immunocompetent patients with diverticulitis (RR, 3.65; 95% CI, 1.73-7.69). By contrast, postoperative mortality after elective surgery was not significantly different between immunocompromised and immunocompetent patients with diverticulitis. In subgroup analysis, the risk of emergency surgery and recurrence was significantly higher in immunocompromised patients with complicated diverticulitis, whereas no significant difference was shown in mild disease. CONCLUSIONS: Immunocompromised patients with diverticulitis should be given the best medical treatment with multidisciplinary approach because they had increased risks of surgery, postoperative morbidity, and mortality than immunocompetent patients.

Korean Association for the Study of Intestinal Diseases guidance for clinical practice of adult inflammatory bowel disease during the coronavirus disease 2019 pandemic: expert consensus statements.

Many unexpected problems have resulted from the unprecedented coronavirus disease 2019 (COVID-19) pandemic. The optimal management of patients with inflammatory bowel disease (IBD) during the COVID-19 pandemic has also been a challenge. Therefore, the Korean Association for the Study of Intestinal Diseases (KASID) developed a consensus statement of experts regarding the management of IBD during the COVID-19 pandemic. This consensus statement made recommendations regarding the risk and treatment of COVID-19 in IBD patients. This statement emphasizes that IBD is not a risk factor for COVID-19, and care should be taken not to exacerbate IBD in patients in remission state by maintaining their medications, except for corticosteroids.

SARS-CoV-2 vaccination for adult patients with inflammatory bowel disease: expert consensus statement by KASID.

Coronavirus disease 2019 (COVID-19), caused by the novel coronavirus, is threatening global health worldwide with unprecedented contagiousness and severity. The best strategy to overcome COVID-19 is a vaccine. Various vaccines are currently being developed, and mass vaccination is in progress. Despite the very encouraging clinical trial results of these vaccines, there is insufficient information on the safety and efficacy of vaccines for inflammatory bowel disease (IBD) patients facing various issues. After reviewing current evidence and international guidelines, the Korean Association for the Study of Intestinal Diseases developed an expert consensus statement on COVID-19 vaccination issues for Korean IBD patients. This expert consensus statement emphasizes that severe acute respiratory syndrome coronavirus 2 vaccination be strongly recommended for IBD patients, and it is safe for IBD patients receiving immunomodulatory therapy.

Recent trends in neonatal mortality in very low birth weight Korean infants: in comparison with Japan and the USA.

With regard to the outcome of intensive neonatal care, one of the most important concerns in neonatology is the mortality rate of very low birth weight infants (VLBWI; birth weight < 1,500 g) and extremely low birth weight infants (ELBWI; birth weight < 1,000 g). The present study was conducted to analyze and compare the mortality of VLBWI and ELBWI and neonatal care among Korean, Japanese, and American newborns. In Korea, the survival rates of VLBWI have increased significantly; they were 31.8% in the early 1960s, 65.8% in the early 1990s, 77.5% in 2002, 84.7% in 2007, and 85.7% in 2009. The survival rates of ELBWI have also increased; they were 8.2% in the early 1960s, 37.4% in the early 1990s, 56.1% in 2002, 67.7% in 2007, and 71.8% in 2009. The survival rates of VLBWI and ELBWI have significantly improved over the past 50 yr in Korea. However, the Korean survival rates of VLBWI and ELBWI are still lower than for similar groups in Japan and the USA. To achieve better outcomes that reach the level of these countries, the organization of perinatal care centers, nationwide neonatal perinatal research networks, and regionalization are needed in Korea.

Decreasing trends of neonatal and infant mortality rates in Korea: compared with Japan, USA, and OECD nations.

Neonatal mortality rate (NMR) and infant mortality rate (IMR) are two of the most important indices reflecting the level of public health of a country. In this review, we investigated changes in NMR and IMR in Korea and compared the results with those of Japan, USA, and OECD nations. During the past 20 yr, NMR and IMR have lowered remarkably from 6.6 and 9.9 in 1993 to 1.7 and 3.2 in 2009, respectively, in Korea. It is an impressive finding that Korean IMR (3.2 in 2009) is lower than the average of OECD nations (4.7 in 2008), and USA (6.3 in 2009), although higher than Japanese IMR (2.8 in 2009). The proportion of NMR among the IMR calculation decreased from 66.7% in 1993 to 53.1% in 2009. The reason the value of Korea was higher than Japan but lower than USA was speculated to be an aspect of the health care service system. Several suggestions in perinatal, neonatal and infantile health care such as establishment of perinatal care center, research network system, regionalization, and new policies for care of pre-term and high risk pregnancy, are elucidated to achieve further improvement on NMR and IMR in Korea.