Korea National Health Insurance Claims Research Articles

The impact of the COVID-19 pandemic on infant obesity: A nationwide retrospective cohort study

BackgroundLifestyle changes, such as those related to the COVID-19 pandemic, including alterations in physical activity and dietary habits, are known to affect pregnancy outcomes. In particular, suboptimal intrauterine conditions during pregnancy are known to influence not only fetal growth but also growth during infancy. However, research on the impact of the environmental changes caused by the COVID-19 pandemic on the growth of infants and children during their early years is lacking. To address this issue, this study evaluated the effect of the COVID-19 pandemic on obesity in infants. MethodsThis retrospective cohort study used the data collected from the Korea National Health Insurance (KNHI) claims database. The data of 1985,678 women who delivered infants between 2015 and 2021 were collected. Women who delivered during the pandemic and those who delivered during the pre-pandemic period were matched in a 1:1 frequency-matched pair procedure for factors such as age, hypertension, diabetes mellitus, preeclampsia, gestational diabetes mellitus, mode of delivery, gestational age at delivery, offspring sex, and birth weight. Finally, 197,580 women were enrolled. The weight and head circumference of infants (4–6 months of age) of the COVID-19 pandemic group were compared with those of the pre-pandemic group. ResultsThe COVID-19 pandemic group infants exhibited significantly higher weight and prevalence of obesity at 4–6 months of age compared to infants in the pre-pandemic group. After adjustment for covariates, pandemic group infants had a higher risk of obesity (odds ratio: 1.54, 95% confidence interval: 1.51–1.57) compared to the pre-pandemic group infants. ConclusionThe COVID-19 pandemic has had a notable impact on the weight of infants aged 4–6 months. This suggests that pandemic conditions may influence the growth of newborns, underscoring the importance of monitoring and assessing trends in the growth of infants born during such crises.

Short-term neonatal and long-term neurodevelopmental outcome of children born term low birth weight

This study aimed to examine the impact of term LBW on short-term neonatal and long-term neurodevelopmental outcomes in children 5–7 years of age. This is a population-based cohort study that merged national data from the Korea National Health Insurance claims and National Health Screening Program for Infants and Children. The participants were women who gave birth at a gestational age of ≥ 37 weeks between 2013 and 2015 in the Republic of Korea, and were tracked during 2020 for the neurodevelopmental surveillance of their children. Among 830,806 women who gave birth during the study period, 31,700 (3.8%) of their babies weighed less than 2500 g. By Cox proportional hazard analysis, children aged 5–7 years who had LBW were associated with any developmental, motor developmental delay, cognitive developmental delay, autism spectrum, attention deficit hyperactivity disorders, and epileptic and febrile seizures.Children born with term LBW were more vulnerable to neurodevelopmental disorders at 5–7 years of age than those with normal and large birth weights. This study further substantiates counseling parents regarding the long-term outcomes of children being born underweight.

Machine learning analysis with population data for the associations of preterm birth with temporomandibular disorder and gastrointestinal diseases.

This study employs machine learning analysis with population data for the associations of preterm birth (PTB) with temporomandibular disorder (TMD) and gastrointestinal diseases. The source of the population-based retrospective cohort was Korea National Health Insurance claims for 489,893 primiparous women with delivery at the age of 25-40 in 2017. The dependent variable was PTB in 2017. Twenty-one predictors were included, i.e., demographic, socioeconomic, disease and medication information during 2002-2016. Random forest variable importance was derived for finding important predictors of PTB and evaluating its associations with the predictors including TMD and gastroesophageal reflux disease (GERD). Shapley Additive Explanation (SHAP) values were calculated to analyze the directions of these associations. The random forest with oversampling registered a much higher area under the receiver-operating-characteristic curve compared to logistic regression with oversampling, i.e., 79.3% vs. 53.1%. According to random forest variable importance values and rankings, PTB has strong associations with low socioeconomic status, GERD, age, infertility, irritable bowel syndrome, diabetes, TMD, salivary gland disease, hypertension, tricyclic antidepressant and benzodiazepine. In terms of max SHAP values, these associations were positive, e.g., low socioeconomic status (0.29), age (0.21), GERD (0.27) and TMD (0.23). The inclusion of low socioeconomic status, age, GERD or TMD into the random forest will increase the probability of PTB by 0.29, 0.21, 0.27 or 0.23. A cutting-edge approach of explainable artificial intelligence highlights the strong associations of preterm birth with temporomandibular disorder, gastrointestinal diseases and antidepressant medication. Close surveillance is needed for pregnant women regarding these multiple risks at the same time.

Long-Term Effect on Ovarian Function After Uterine Artery Embolization During the Postpartum Period: A Nationwide Population-Based Study.

Uterine artery embolization(UAE) is widely used in obstetrical indications, including postpartum bleeding and placental implantation abnormality, to manage many conditions to conserve the uterus. However, physicians are concerned about future fertility or ovarian function due to the occlusion of major pelvic vessels in the uterine artery embolization. However, there are limited data related to UAE usage during the postpartum period. This study was to evaluate the impact of UAE during the postpartum period on primary ovarian failure(POF), menstrual disorders, and infertility in women. Using the Korea National Health Insurance claims database, all pregnant women who delivered between January 2007 and December 2015 and underwent UAE during the postpartum period were identified. The occurrence of POF, female infertility, and menstrual disorders after delivery was evaluated. Using Cox proportional hazards models, the adjusted hazard ratios and 95% confidence intervals were estimated. 779,612 cases were analyzed in the study with 947 women in the UAE group. After delivery, the incidence of POF (0.84% vs.0.27%, P<.0001) and female infertility (10.24% vs. 6.89%, P<.0001) were higher in UAE group than in the control group. After adjusting for covariates, the POF risk was significantly higher in UAE group than in the control group (HR 2.37, 95% CI 1.16-4.82). The risk for the disorder of menstrual frequency (HR 1.28, 95% CI 1.10-1.50) and female infertility (HR 1.37, 95% CI 1.10-1.71) was significantly higher in UAE group than in the control group. This study confirmed UAE during the postpartum period is a risk factor for POF after delivery.

Preterm birth and maternal heart disease: A machine learning analysis using the Korean national health insurance database.

Maternal heart disease is suspected to affect preterm birth (PTB); however, validated studies on the association between maternal heart disease and PTB are still limited. This study aimed to build a prediction model for PTB using machine learning analysis and nationwide population data, and to investigate the association between various maternal heart diseases and PTB. A population-based, retrospective cohort study was conducted using data obtained from the Korea National Health Insurance claims database, that included 174,926 primiparous women aged 25-40 years who delivered in 2017. The random forest variable importance was used to identify the major determinants of PTB and test its associations with maternal heart diseases, i.e., arrhythmia, ischemic heart disease (IHD), cardiomyopathy, congestive heart failure, and congenital heart disease first diagnosed before or during pregnancy. Among the study population, 12,701 women had PTB, and 12,234 women had at least one heart disease. The areas under the receiver-operating-characteristic curves of the random forest with oversampling data were within 88.53 to 95.31. The accuracy range was 89.59 to 95.22. The most critical variables for PTB were socioeconomic status and age. The random forest variable importance indicated the strong associations of PTB with arrhythmia and IHD among the maternal heart diseases. Within the arrhythmia group, atrial fibrillation/flutter was the most significant risk factor for PTB based on the Shapley additive explanation value. Careful evaluation and management of maternal heart disease during pregnancy would help reduce PTB. Machine learning is an effective prediction model for PTB and the major predictors of PTB included maternal heart disease such as arrhythmia and IHD.

Prevalence of asthma in premature infants using data from 2002–2018 Korea national health insurance claims data

Prevalence of asthma in premature infants using data from 2002–2018 Korea national health insurance claims data

Associations of Preterm Birth with Dental and Gastrointestinal Diseases: Machine Learning Analysis Using National Health Insurance Data.

This study uses machine learning with large-scale population data to assess the associations of preterm birth (PTB) with dental and gastrointestinal diseases. Population-based retrospective cohort data came from Korea National Health Insurance claims for 124,606 primiparous women aged 25-40 and delivered in 2017. The 186 independent variables included demographic/socioeconomic determinants, disease information, and medication history. Machine learning analysis was used to establish the prediction model of PTB. Random forest variable importance was used for identifying major determinants of PTB and testing its associations with dental and gastrointestinal diseases, medication history, and socioeconomic status. The random forest with oversampling data registered an accuracy of 84.03, and the areas under the receiver-operating-characteristic curves with the range of 84.03-84.04. Based on random forest variable importance with oversampling data, PTB has strong associations with socioeconomic status (0.284), age (0.214), year 2014 gastroesophageal reflux disease (GERD) (0.026), year 2015 GERD (0.026), year 2013 GERD (0.024), progesterone (0.024), year 2012 GERD (0.023), year 2011 GERD (0.021), tricyclic antidepressant (0.020) and year 2016 infertility (0.019). For example, the accuracy of the model will decrease by 28.4%, 2.6%, or 1.9% if the values of socioeconomic status, year 2014 GERD, or year 2016 infertility are randomly permutated (or shuffled). By using machine learning, we established a valid prediction model for PTB. PTB has strong associations with GERD and infertility. Pregnant women need close surveillance for gastrointestinal and obstetric risks at the same time.

Blood Transfusion, All-Cause Mortality and Hospitalization Period in COVID-19 Patients: Machine Learning Analysis of National Health Insurance Claims Data.

This study presents the most comprehensive machine-learning analysis for the predictors of blood transfusion, all-cause mortality, and hospitalization period in COVID-19 patients. Data came from Korea National Health Insurance claims data with 7943 COVID-19 patients diagnosed during November 2019-May 2020. The dependent variables were all-cause mortality and the hospitalization period, and their 28 independent variables were considered. Random forest variable importance (GINI) was introduced for identifying the main factors of the dependent variables and evaluating their associations with these predictors, including blood transfusion. Based on the results of this study, blood transfusion had a positive association with all-cause mortality. The proportions of red blood cell, platelet, fresh frozen plasma, and cryoprecipitate transfusions were significantly higher in those with death than in those without death (p-values &lt; 0.01). Likewise, the top ten factors of all-cause mortality based on random forest variable importance were the Charlson Comorbidity Index (53.54), age (45.68), socioeconomic status (45.65), red blood cell transfusion (27.08), dementia (19.27), antiplatelet (16.81), gender (14.60), diabetes mellitus (13.00), liver disease (11.19) and platelet transfusion (10.11). The top ten predictors of the hospitalization period were the Charlson Comorbidity Index, socioeconomic status, dementia, age, gender, hemiplegia, antiplatelet, diabetes mellitus, liver disease, and cardiovascular disease. In conclusion, comorbidity, red blood cell transfusion, and platelet transfusion were the major factors of all-cause mortality based on machine learning analysis. The effective management of these predictors is needed in COVID-19 patients.

Trend changes and factor analysis of endometrial hyperplasia in patients with polycystic ovarian syndrome based on the Korean National Health Insurance Database

BackgroundPolycystic ovary syndrome (PCOS) is a common endocrine disorder associated with an increased risk of other gynecological disorders, such as endometrial hyperplasia (EH). However, substantial factors in the comorbidity of EH and PCOS remain to be investigated. We analyzed trend changes in PCOS and factors related to the comorbidity of PCOS and EH using data from the Korea National Health Insurance (KNHI) claims database.MethodsThe data for this population-based study of people diagnosed with PCOS or EH in Korea from 2009 to 2016 were collected from the KNHI claims database between 2007 and 2017. We conducted a trend analysis of the prevalence and incidence of PCOS and EH. In addition, we performed a logistic regression analysis to identify risk factors associated with EH incidence in people with PCOS using the matched case-control methodology.ResultsThe average annual growth rate of the incidence of PCOS was 14.1% from 2009 to 2016, whereas the EH rate increased by only 3.4% annually. Comorbidities, type 2 diabetes, obesity, hypertension, hyperlipidemia, and infertility, increased the risk of EH in PCOS patients. Additionally, the cumulative duration of oral contraceptive & progestin treatment for PCOS correlated highly with the comorbidity of EH and PCOS.ConclusionsWe confirmed the relationship between PCOS and EH using big data suitable for time series analyses of the diagnosis and treatment of diseases. Endometrial evaluation should be done with more caution if oral contraceptives & progestins have been used for a long time.

COVID-19 and vaccination during pregnancy: a systematic analysis using Korea National Health Insurance claims data.

This study systematically analyzed coronavirus disease 2019 (COVID-19) and vaccination details during pregnancy by using the national health insurance claims data. Population-based retrospective cohort data of 12,399,065 women aged 15-49 years were obtained from the Korea National Health Insurance Service claims database between 2019 and 2021. Univariate analysis was performed to compare the obstetric outcomes of pregnant women (ICD-10 O00-O94) and their newborns (ICD-10 P00-P96) with and without COVID-19. Univariate analysis was also performed to compare the age and obstetric outcomes of pregnant women receiving different types of vaccines. The percentage of pregnant women with COVID-19 during pregnancy was 0.11%. Some obstetric outcomes of pregnant women with COVID-19, including the rates of preterm birth or cesarean delivery, were significantly better than those of pregnant women without COVID-19. The rate of miscarriage was higher in pregnant women with COVID-19 than without COVID-19. However, the outcomes of newborns of women with and without COVID-19 were not significantly different. Regarding vaccination type, obstetric outcomes of pregnant women appeared to be worse with the viral vector vaccine than with the mRNA vaccine. To the best of our knowledge, this is the first study to systematically analyze COVID-19 and vaccination details during pregnancy using the national health insurance claims data in Korea. The obstetric outcomes in pregnant women with and without COVID-19 and their newborns were similar.

Prevalence and patterns of the concurrent use of anticholinergics for the motor symptoms of Parkinson’s disease and acetylcholinesterase inhibitors in Parkinson’s disease patients with dementia: a cross-sectional study using Korea National Health Insurance claims data

BackgroundThe concurrent use of anticholinergics and acetylcholinesterase inhibitors (ACHEIs) in Parkinson’s disease (PD) patients with dementia should be avoided because the opposing pharmacological actions of both drugs reduce the treatment efficacy. We aimed to investigate the prevalence of the concurrent use of these two types of drugs in Korean patients.MethodsIn the 2017 Health Insurance Review and Assessment Service–National Aged Patient Sample data, comprising insurance claims records for a 10% random sample of patients aged ≥ 65 years in Korea, “concurrent use” was defined as the overlapping of anticholinergic and ACHEI doses for at least 2 months.ResultsAmong 8,845 PD patients with dementia, 847 (9.58%) were co-administered anticholinergics, used to treat the motor symptoms of PD, and ACHEIs for a mean duration of 7.7 months. A total of 286 (33.77% of all co-administered) patients used both drug types concurrently all year. About 80% of concurrent users were prescribed each drug by the same prescriber, indicating that coadministration may not be due to a lack of information sharing between providers. Logistic regression analysis showed that patients mainly treated at clinics (odds ratio (OR), 1.541; 95% confidence interval (CI), 1.158–2.059), hospitals (OR, 2.135; 95% CI, 1.586–2.883), and general hospitals (OR, 1.568; 95% CI, 1.221–2.028) were more likely to be co-prescribed anticholinergics and ACHEIs than those mainly treated at tertiary-care hospitals. PD patients with dementia treated at healthcare organizations located in areas other than the capital city had an approximately 22% higher risk of concurrent use (OR: 1.227, 95% CI: 1.046–1.441).ConclusionsThe concurrent use of anticholinergics for the motor symptoms of PD and ACHEIs in elderly Korean PD patients with dementia cannot be ignored, and strategies that mitigate potentially inappropriate concurrent drug use are required.

The Potential Economic Benefits of an Alarm Service in Order Communication Systems in Korea: a Cost-Effectiveness Analysis of Less-Intensive Fracture Liaison Services Based on a Prospective Cohort Study.

An alarm service in an order communication system (OCS) was found to be effective at increasing the rate of dual-energy X-ray absorptiometry (DXA) testing and treatment in South Korea, but its cost-effectiveness remains unknown. We used a Markov model to determine the cost-effectiveness of the alarm service in the OCS compared to no alarm service for the post-fracture management of subjects aged 50years and older with fragility fractures. DXA testing and treatment data were collected from a prospective cohort study. The prevalence of osteoporotic fractures, the subsequent risk of hip fracture, and healthcare costs were obtained using Korea National Health Insurance claims data. The lifetime cost and quality-adjusted life-years (QALYs) gained were estimated from a healthcare perspective. A probabilistic sensitivity analysis was performed to examine the uncertainty of the results. The alarm service increased treatment by 125 per 1000 patients and prevented 3 hip fractures per 1000 patients. The alarm service cost an additional 249,393 KRW and resulted in an increase of 0.008 QALYs per patient compared to no alarm service. The incremental cost-effectiveness ratio was 31,174,125 KRW (26,843 USD) per QALY gained. The alarm service was cost-effective than no alarm service if the willingness to pay setting as 1GDP per capita (29,288 USD) per QALY gained. This study shows that less-intensive fracture liaison services, such as an alarm service, are cost-effective for patients aged 50years and older with osteoporotic fractures in Korea. An intensive model, including enhanced identification and education, could further prevent the risk of refracture and improve cost-effectiveness.

Fragmentation of care and colorectal cancer survival in South Korea: comparisons according to treatment at multiple hospitals.

Fragmented cancer care (FC) means that patients visit multiple providers for treatment, which is common in cancer care. While FC is associated with poor health outcomes in patients with colorectal cancer (CRC) worldwide, there is still a lack of evidence in South Korea. We investigated the association between FC and 5-year morality in patients with CRC using population-based claims data. The study population was followed up from 2002 to 2015. Data were collected from Korea National Health Insurance claims. Participants comprised patients with CRC diagnosed with International Classification of Diseases (ICD)-10 (C18.x-C20.x) and a special claim code for cancer (V193). Data were analyzed using the Kaplan-Meier curve with a log-rank test and Cox proportional hazard model. The effect of FC on patients' 5-year survival was examined. Of 3467 patients with CRC, 20.0% had experienced FC. FC was significantly associated with an increased risk of 5-year mortality (hazard ratio 1.516, 95% confidence interval 1.274-1.804). FC was prevalent in those who had a low income level, underwent chemotherapy, did not undergo radiation therapy, and did not visit a tertiary hospital for their first treatment. Efforts to decrease FC and integrate complex cancer care within appropriate healthcare delivery systems may improve survivorship among patients with CRC.

Prior pregnancy complications and maternal cardiovascular disease in young Korean women within 10\xa0years after pregnancy

BackgroundThis study aimed to compare obstetric outcomes in Korean women with and without future cardiovascular disease (CVD) within 10 years after pregnancy, and assessed whether pregnancy complications are independent risk factors, and whether the combination of pregnancy complications has an additive function for risk factors for CVD.MethodsThis was a nationwide population-based study combining the database of the Korea National Health Insurance claims and National Health Screening Programs to assess preeclampsia, low birth weight (LBW), and preterm delivery as risk factors for CVD. Cox proportional hazards models was used to evaluate the risk of total CVD, ischemic heart disease (IHD), and stroke after the pregnancy complications, with adjustment for potential confounding variables.ResultsWomen with CVD were likely to have a higher prevalence of pregnancy complications than women without CVD. The risk of total CVD was associated with preeclampsia (adjusted hazard ratio (HR), 1.60 [95% confidence interval (CI) 1.50–1.72]), LBW (1.20 [1.12–1.28]), and preterm delivery (1.32 [1.22–1.42]), after adjustment for confounders, including cardiovascular risk factors before pregnancy. The risk estimates of pregnancy complications for IHD were higher than those for stroke. In this study, the risk of total CVD was higher in the combined presence of preeclampsia and preterm delivery (2.23 [1.57–3.17] or all three complications (2.06 [1.76–2.40]), relative to no complications. The highest HR was noted in the risk of all pregnancy complications for IHD (2.39 [1.98–2.89]).ConclusionPreeclampsia, preterm delivery, and LBW were independently associated with CVD in young Korean women. In addition, the combination of pregnancy complications had less-than-additive effects on CVD incidence.

Relationship between continuity of care and clinical outcomes in patients with dyslipidemia in Korea: a real world claims database study

Dyslipidemia is a risk factor for atherosclerotic cardiovascular disease and requires proactive management. This study aimed to investigate the association between care continuity and the outcomes of patients with dyslipidemia. We conducted a retrospective cohort study on patients with dyslipidemia by employing the Korea National Health Insurance claims database during the period 2007–2018. The Continuity of Care Index (COCI) was used to measure continuity of care. We considered incidence of atherosclerotic cardiovascular disease as a primary outcome. A Cox's proportional hazards regression model was used to quantify risks of primary outcome. There were 236,486 patients newly diagnosed with dyslipidemia in 2008 who were categorized into the high and low COC groups depending on their COCI. The adjusted hazard ratio for the primary outcome was 1.09 times higher (95% confidence interval: 1.06–1.12) in the low COC group than in the high COC group. The study shows that improved continuity of care for newly-diagnosed dyslipidemic patients might reduce the risk of atherosclerotic cardiovascular disease.

The Effect of Statins on Mortality of Patients With Chronic Kidney Disease Based on Data of the Observational Medical Outcomes Partnership Common Data Model (OMOP-CDM) and Korea National Health Insurance Claims Database.

The role of statins in chronic kidney disease (CKD) has been extensively evaluated, but it remains controversial in specific population such as dialysis-dependent CKD. This study examined the effect of statins on mortality in CKD patients using two large databases. In data from the Observational Medical Outcomes Partnership Common Data Model (OMOP-CDM) from two hospitals, CKD was defined as an estimated glomerular filtration rate < 60 mL/min/m2; we compared survival between patients with or without statin treatment. As a sensitivity analysis, the results were validated with the Korea National Health Insurance (KNHI) claims database. In the analysis of CDM datasets, statin users showed significantly lower risks of all-cause and cardiovascular mortality in both hospitals, compared to non-users. Similar results were observed in CKD patients from the KNHI claims database. Lower mortality in the statin group was consistently evident in all subgroup analyses, including patients on dialysis and low-risk young patients. In conclusion, we found that statins were associated with lower mortality in CKD patients, regardless of dialysis status or other risk factors.

Joint Replacement Surgery in Patients with Rheumatoid Arthritis in South Korea: Analysis of a Large National Database.

We aimed to investigate the current trend of joint replacement surgery incidence in patients with rheumatoid arthritis (RA) in South Korea and to compare the incidence of joint replacement surgery in each affected joint. We performed this big data analysis to investigate the current trend of joint replacement surgery incidence in patients with RA in South Korea and to compare the incidence of joint replacement surgery in each affected joint. This retrospective study was based on data from the Korea National Health Insurance claims database. The prevalence of RA increased every year (0.13% in 2008, 0.25% in 2016). The number of newly diagnosed patients increased from 29,184 in 2010 to 38,347 in 2016. The incidence rate of joint replacement surgery in patients with RA increased from 0.72% in 2010 to 4.03% in 2016. The knee (68.3%) was the most commonly replaced joint. The relative risk (RR) of additional joint replacement surgery was highest for the shoulder joint (RR,1.454; 95% confidence interval, 0.763-2.771). The median time from diagnosis to surgery was the shortest in the elbow joint (379 days) and the longest in the shoulder joint (955 days). The median time for each joint was short in order of the elbows, ankles, hips, knees, and shoulders (p < 0.01). The most frequently and initially replaced joints were different, but the prevalence and incidence of RA, as well as those of joint replacement surgery, have recently increased in South Korea. Joint replacement surgery in RA was the highest for the knee joint. The median time from diagnosis to surgery was shortest for the elbow, followed by the ankle, hip, knee, and shoulder. Regardless of whether patients are symptomatic, evaluation of large joints such as the knee, elbow, ankle, and hip should be considered from an early stage.

In utero exposure to ritodrine during pregnancy and risk of autism in their offspring until 8\xa0years of age

Beta-2 adrenergic receptor (B2AR) agonists, used as asthma treatments and tocolytics during pregnancy, have recently been reported to be associated with autism in their offspring. However, the particular link between autism and ritodrine, a common type of B2AR agonist used solely as tocolytics, has never been substantiated with any nationwide database. Thus, we aimed to examine the association between in utero exposure of ritodrine and the risk of autism in their offspring using a national database. This population-based cohort study was conducted by merging the Korea National Health Insurance claims database and National Health Screening Program for Infants and Children database. These databases included all women who had delivered singleton between January 2007 and December 2008 in Korea. Out of the total 770,016 mothers, 30,959 (4.02%) were exposed to ritodrine during pregnancy, and 5583 (0.73%) of their children were identified as having autism, defined until 8 years of age. According to our analysis, the overall cumulative incidence of autism up to 8 years was 1.37% in ritodrine exposure group and 0.70% in ritodrine non-exposure group (p < 0.05, log-rank test). By Cox proportional hazard analysis, use of ritodrine in preterm birth was associated with significantly higher hazard of autism [adjusted hazard ratio: 1.23, 95% CI 1.04–1.47], after adjusting for confounding variables including maternal age, parity, cesarean section, preterm labor, steroid use, birth weight, gender, and preeclampsia. Thus, in utero exposure to ritodrine was associated with an increased risk of autism in their offspring.

Mortality and morbidity in children with asthma: A nationwide study in Korea

ObjectiveChildhood mortality due to asthma remains problematic; however, asthma-related mortality in Korean children has not been previously described. This study aimed to estimate asthma mortality and morbidity and determine to what extent asthma contributes to childhood mortality in Korea. MethodsData from 9 to 12 million children (aged < 18 years) per year recorded for each year between 2002 and 2015 were retrieved from the Korea National Health Insurance claims database. Patients with asthma during the year preceding death were investigated. Causes of death were analysed using data obtained from the Korean Statistical Information Service database. Cause-specific mortality was examined, and the mortality rate of children with asthma was compared to that of the general paediatric population with respect to the cause of death and age. Hospital use by patients with asthma, including intensive care unit admission and hospitalisation, was analysed. ResultsAsthma mortality decreased from 0.09 per 100,000 children in 2003 to 0.02 per 100,000 children in 2014, with an average mortality of 0.06 per 100,000 children. Mortality due to respiratory diseases was four times more common in patients with asthma than in the general population of children aged >5 years, despite decreases in asthma-related mortality. Asthma-related hospitalisations and intensive care interventions tended to decrease throughout the study period. ConclusionsAsthma mortality declined in children between 2003 and 2015 in Korea. Children with asthma are at a higher risk of death from respiratory diseases than the general population.

Pregnancy Outcomes Following Laparoscopic and Open Surgery in Pelvis during Pregnancy: a Nationwide Population-based Study in Korea.

BackgroundNon-obstetric surgery during pregnancy is associated with adverse obstetric and fetal outcomes. The aim of this study was to investigate the risk of adverse pregnancy outcomes for women who underwent non-obstetric pelvic surgery during pregnancy compared with that of women that did not undergo surgery.MethodsStudy data from women who gave birth in Korea were collected from the Korea National Health Insurance claims database between 2006 and 2016. We identified pregnant women who underwent abdominal non-obstetric pelvic surgery by laparoscopy or laparotomy from the database. Pregnancy outcomes including preterm birth, low birth weight (LBW), cesarean section (C/S), gestational hypertension, gestational diabetes, and postpartum hemorrhage were identified. The adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the pregnancy outcomes were estimated by multivariate regression models.ResultsData from 4,439,778 women were collected for this study. From 2006–2016, 9,417 women from the initial cohort underwent non-obstetric pelvic surgery (adnexal mass resection, appendectomy) during pregnancy. Multivariate logistic regression analysis indicated that preterm birth (HR, 2.01; 95% CI, 1.81–2.23), LBW (HR, 1.62; 95% CI, 1.46–1.79), C/S (HR, 1.13; 95% CI, 1.08–1.18), and gestational hypertension (HR, 1.35; 95% CI, 1.18–1.55) were significantly more frequent in women who underwent non-obstetric surgery during pregnancy compared to pregnant women who did not undergo surgery. When the laparoscopic and laparotomy groups were compared for risk of fetal outcomes, the risk of LBW was significantly decreased in laparoscopic adnexal resection during pregnancy compared to laparotomy (odds ratio, 0.62; 95% CI, 0.40–0.95).ConclusionNon-obstetric pelvic surgery during pregnancy was associated with a higher risk of preterm birth, LBW, gestational hypertension, placenta previa, placental abruption, and C/S. Although the benefits and safety of laparoscopy during pregnancy appear similar to those of laparotomy in regard to pregnancy outcomes, laparoscopic adnexal mass resection was associated with a lower risk of LBW.