National trend in the prevalence and mortality of COPD in South Korea from 2008 to 2017.

BACKGROUND: Existing studies on chronic obstructive pulmonary disease (COPD) in Korea lack full population coverage, relying on small sample sizes. Therefore, this study aims to investigate the prevalence and mortality of COPD in the entire Korean population. METHODS: This serial cross-sectional study used national databases, linking the National Health Information Database (2008-2017) with Causes of Death Statistics. Identification of individuals with COPD used diagnostic codes (International Classification of Diseases-10: J41-J44) or a history of COPD-related hospitalisation, focusing on adults aged 40 and above. Prevalence and mortality rates, calculated for 2008-2017, encompassed both crude and age-standardised and sex-standardised measures. A multivariate Poisson regression model estimated the association between COPD and all-cause and cause-specific mortality, presenting incidence rate ratios (IRRs) and 95% CIs, using data from the year 2017. RESULTS: Age-adjusted COPD prevalence exhibited a notable increase from 2008 (7.9%) to 2017 (16.7%) in both sexes. The prevalences of diabetes mellitus, hypertension, dyslipidaemia, ischaemic heart disease, cancer, osteoporosis and tuberculosis were higher in the COPD group than in the group without COPD (p for all <0.001). The incidence of stroke and myocardial infarction (p for all <0.001) and overall mortality were higher in the COPD group (adjusted IRR 1.23, 95% CI 1.22 to 1.24, p<0.001). In particular, incidence rate and risk of mortality due to lung cancer were higher than that of those without COPD compared with other cancer types (adjusted IRR 2.51, 95% CI 2.42 to 2.60, p<0.001). It was significantly higher the incidence rate and risk of mortality among group with COPD than those without COPD in lower respiratory disease (adjusted IRR 16.62, 95% CI 15.07 to 18.33, p<0.001), asthma (adjusted IRR 6.41, 95% CI 5.47 to 7.51, p<0.001) and bronchiectasis (adjusted IRR 11.77, 95% CI 7.59 to 18.26, p<0.001), respectively. DISCUSSION: Our study showed that the prevalence of COPD is gradually increasing from 9.2% in 2009 to 16.7% in 2018. Furthermore, in overall (all-cause) mortality, it was significantly higher in group with COPD than in group without COPD. The mortality rate of group with COPD was much higher than the overall mortality rate but is gradually decreasing.

Oleanolic Acid Acetate Alleviates Cisplatin-Induced Nephrotoxicity via Inhibition of Apoptosis and Necroptosis In Vitro and In Vivo.

Cisplatin is a widely used anti-cancer drug for treating solid tumors, but it is associated with severe side effects, including nephrotoxicity. Various studies have suggested that the nephrotoxicity of cisplatin could be overcome; nonetheless, an effective adjuvant drug has not yet been established. Oleanolic acid acetate (OAA), a triterpenoid isolated from Vigna angularis, is commonly used to treat inflammatory and allergic diseases. This study aimed to investigate the protective effects of OAA against cisplatin-induced apoptosis and necroptosis using TCMK-1 cells and a mouse model. In cisplatin-treated TCMK-1 cells, OAA treatment significantly reduced Bax and cleaved-caspase3 expression, whereas it increased Bcl-2 expression. Moreover, in a cisplatin-induced kidney injury mouse model, OAA treatment alleviated weight loss in the body and major organs and also relieved cisplatin-induced nephrotoxicity symptoms. RNA sequencing analysis of kidney tissues identified lipocalin-2 as the most upregulated gene by cisplatin. Additionally, necroptosis-related genes such as receptor-interacting protein kinase (RIPK) and mixed lineage kinase domain-like (MLKL) were identified. In an in vitro study, the phosphorylation of RIPKs and MLKL was reduced by OAA pretreatment in both cisplatin-treated cells and cells boosted via co-treatment with z-VAD-FMK. In conclusion, OAA could protect the kidney from cisplatin-induced nephrotoxicity and may serve as an anti-cancer adjuvant.

Bakuchicin alleviates ovalbumin-induced allergic asthma by regulating M2 macrophage polarization.

OBJECTIVE: Asthma is an airway inflammatory disease caused by activation of numerous immune cells including macrophages. Bakuchicin (BKC) is known to exhibit anti-inflammatory effects and type 2 T helper (Th2) regulation, but has not been investigated for airway inflammation. This study aimed to evaluate the effects of BKC on airway inflammation and demonstrate the mechanisms of macrophage polarization. METHODS: The anti-inflammatory effects were determined using lipopolysaccharide (LPS)-stimulated macrophages. The ovalbumin (OVA)-induced asthma mouse model was used to evaluate the effects of BKC on airway inflammation and Th2 responses. Moreover, the effect of BKC on macrophage polarization was confirmed in bone marrow-derived macrophages (BMDMs) differentiation. RESULTS: BKC suppressed nitric oxide production and expression of pro-inflammatory cytokines by inhibiting signaling pathway in LPS-stimulated macrophages. In an OVA-induced asthma model, BKC treatment alleviated histological changes and mast cell infiltration and reduced the levels of eosinophil peroxidase, ß-hexosaminidase, and immunoglobulin levels. In addition, BKC alleviated Th2 responses and M2 macrophage populations in bronchoalveolar fluid. In BMDMs, BKC suppressed IL-4-induced M2 macrophage polarization and the expression of M2 markers such as arginase-1 and Fizz-1 through inhibiting sirtuin 2 levels. CONCLUSION: BKC could be a drug candidate for the treatment of allergic asthma.

Anti-Inflammatory Effects of Clematis terniflora Leaf on Lipopolysaccharide-Induced Acute Lung Injury.

For centuries, natural products are regarded as vital medicines for human survival. Clematis terniflora var. mandshurica (Rupr.) Ohwi is an ingredient of the herbal medicine, Wei Ling Xian, which has been used in Chinese medicine to alleviate pain, fever, and inflammation. In particular, C. terniflora leaves have been used to cure various inflammatory diseases, including tonsillitis, cholelithiasis, and conjunctivitis. Based on these properties, this study aimed to scientifically investigate the anti-inflammatory effect of an ethanol extract of leaves of C. terniflora (EELCT) using activated macrophages that play central roles in inflammatory response. In this study, EELCT inhibited the essential inflammatory mediators, such as nitric oxide, cyclooxygenase-2, tumor necrosis factor-α, interleukin- (IL-) 6, IL-1ß, and inducible nitric oxide synthase, by suppressing the nuclear factor-κB and mitogen-activated protein kinase activation in macrophages. Acute lung injury (ALI) is a fatal respiratory disease accompanied by serious inflammation. With high mortality rate, the disease has no effective treatments. Therefore, new therapeutic agents must be developed for ALI. We expected that EELCT can be a promising therapeutic agent for ALI by reducing inflammatory responses and evaluated its action in a lipopolysaccharide- (LPS-) induced ALI model. EELCT alleviated histological changes, immune cell infiltration, inflammatory mediator production, and protein-rich pulmonary edema during ALI. Collectively, our results may explain the traditional usage of C. terniflora in inflammatory diseases and suggest the promising potential of EELCT as therapeutic candidate for ALI.

Data resource profile: the allergic disease database of the Korean National Health Insurance Service.

Researchers have been interested in probing how the environmental factors associated with allergic diseases affect the use of medical services. Considering this demand, we have constructed a database, named the Allergic Disease Database, based on the National Health Insurance Database (NHID). The NHID contains information on demographic and medical service utilization for approximately 99% of the Korean population. This study targeted 3 major allergic diseases, including allergic rhinitis, atopic dermatitis, and asthma. For the target diseases, our database provides daily medical service information, including the number of daily visits from 2013 and 2017, categorized by patients' characteristics such as address, sex, age, and duration of residence. We provide additional information, including yearly population, a number of patients, and averaged geocoding coordinates by eup, myeon, and dong district code (the smallest-scale administrative units in Korea). This information enables researchers to analyze how daily changes in the environmental factors of allergic diseases (e.g., particulate matter, sulfur dioxide, and ozone) in certain regions would influence patients' behavioral patterns of medical service utilization. Moreover, researchers can analyze long-term trends in allergic diseases and the health effects caused by environmental factors such as daily climate and pollution data. The advantages of this database are easy access to data, additional levels of geographic detail, time-efficient data-refining and processing, and a de-identification process that minimizes the exposure of identifiable personal information. All datasets included in the Allergic Disease Database can be downloaded by accessing the National Health Insurance Service data sharing webpage (https://nhiss.nhis.or.kr).

Income differences in screening, incidence, postoperative complications, and mortality of thyroid cancer in South Korea: a national population-based time trend study.

BACKGROUND: The incidence of thyroid cancer (TC) has increased rapidly over the past few decades in Korea. This study investigated whether the TC epidemic has been driven by overdiagnosis. METHODS: We calculated the TC screening rate from mid-2008 through mid-2014, and the incidence, postoperative complication, and mortality rates of TC between 2006 and 2015, using data from the Korea Community Health Survey, the National Health Insurance Database, and the cause-of-death data of Statistics Korea. Trends in age-standardized rates of all indicators were examined, along with income gaps therein. Analyses were conducted for lung cancer and stroke as negative control outcomes. RESULTS: The incidence rate of TC increased from 46.6 per 100,000 to 115.0 per 100,000 between 2006 and 2012, and then decreased to 63.5 per 100,000 in 2015. Despite these remarkable changes in incidence, mortality did not fluctuate during the same period. High income was associated with high rates of screening, incidence, and postoperative complications, while low income showed an association with a high mortality rate. Analyses using negative control outcomes showed that high income was associated with low rates of both incidence and mortality, which contrasted with the patterns of TC. The recent decreases in TC incidence and postoperative complications, which reflect societal concerns about the overdiagnosis of TC, were more pronounced in high-income individuals than in low-income individuals. CONCLUSIONS: The time trends in income gaps in screening, incidence, postoperative complications, and mortality of TC, as well as negative control outcomes, provided corroborating evidence of TC overdiagnosis in Korea.

AGK2 ameliorates mast cell-mediated allergic airway inflammation and fibrosis by inhibiting FcεRI/TGF-ß signaling pathway.

Asthma is characterized by airway hyperresponsiveness and allergic inflammation, detrimentally affecting the patients' quality of life. The development of new drugs for the treatment of asthma is warranted to alleviate these issues. Recent studies have demonstrated that sirtuin2 (SIRT2) aggravates asthmatic inflammation by up-regulation of T-helper type 2 responses and macrophage polarization. However, effects of SIRT2 on mast cell activation remain obscure. In this study, we investigated the effects of AGK2, an inhibitor for SIRT2, on mast cell-mediated allergic airway inflammation. Pre-treatment with AGK2 inhibited degranulation of mast cells by suppressing the FcεRI signaling pathway and intracellular calcium influx. The expression of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-4, IL-5, IL-6, and IL-8, was inhibited via regulation of transcription factors such as NF-κB and NRF2. These effects of AGK2 were verified in passive cutaneous anaphylaxis and acute lung injury animal models. AGK2 attenuated Evans blue pigmentation by inhibiting mast cell activation and lung barrier dysfunction by inhibiting inflammatory responses in these animal models. In the ovalbumin (OVA)-induced allergic airway inflammation murine model, AGK2 alleviated allergic asthma symptoms such as lung histological changes (immune cell and mast cell infiltration, collagen deposition, and α-smooth muscle actin expression) and serum immunoglobulins (Ig) levels (IgE, OVA-specific IgE, IgG1, and IgG2a). Moreover, AGK2 reduced the levels of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-4, IL-5, and IL-6) and inflammatory mediators (myeloperoxidase, eosinophil peroxidase, and tumor growth factor-α) in the bronchoalveolar lavage fluid and lung tissues. In addition, the anti-fibrotic effects of AGK2 were verified using lung epithelial cells and TGF-ß/Smad reporter stable cells. In conclusion, our findings suggest that SIRT2 plays a role in mast cell-mediated airway inflammatory disease. Therefore, AGK2 is a good potential candidate for treating allergic asthma and lung inflammation.

Differences in diagnosis, treatment, and survival rate of acute myeloid leukemia with or without disabilities: A national cohort study in the Republic of Korea.

We analyzed the patterns of diagnosis, treatment, and prognoses of acute myeloid leukemia (AML) patients with and without disabilities. The data were collected from the National Disability Database, the Korean Central Cancer Registry, and the Korean National Health Insurance claim database. We built a cohort of 2 776 450 people with disabilities and a nondisabled cohort of 8 329 350 people who were selected at a ratio of 1:3 by matching age and sex. From this population, adult patients who were diagnosed with AML were analyzed. The number of patients with AML were 26.74 per 100 000 in people without disabilities and 20.39 per 100 000 in those with disabilities (P < .0001). The proportion of AML patients receiving chemotherapy and those of patients receiving transplants were significantly lower in the disabled population than that of nondisabled populations (71.2% vs 77.1%, P = .0031, and 17.5% vs 26.9%, P = .002). This trend was more pronounced in subgroups of communication disability and major internal organ disorder. The median survival was 10.8 months for patients with disabilities, which was significantly shorter than 17.1 months for those without a disability (P = .002). Individuals with disabilities have a low diagnosis rate of AML and undergo less active treatment, which results in inferior prognosis.

Income-related inequality in quality-adjusted life expectancy in Korea at the national and district levels.

BACKGROUND: The aim of this study was to measure differences in quality-adjusted life expectancy (QALE) by income in Korea at the national and district levels. METHODS: Mortality rates and EuroQol-5D (EQ-5D) scores were obtained from the National Health Information Database of the National Health Insurance Service and the Korea Community Health Survey, respectively. QALE and differences in QALE among income quintiles were calculated using combined 2008-2014 data for 245 districts in Korea. Correlation analyses were conducted to investigate the associations of neighborhood characteristics with QALE and income gaps therein. RESULTS: QALE showed a graded pattern of inequality according to income, and increased over time for all levels of income and in both sexes, except for low-income quintiles among women, resulting in a widened inequality in QALE among women. In all 245 districts, pro-rich inequalities in QALE were found in both men and women. Districts with higher QALE and smaller income gaps in QALE were concentrated in metropolitan areas, while districts with lower QALE and larger income gaps in QALE were found in rural areas. QALE and differences in QALE by income showed relatively close correlations with socioeconomic characteristics, but relatively weak correlations with health behaviors, except for smoking and indicators related to medical resources. CONCLUSIONS: This study provides evidence of income-based inequalities in health measured by QALE in all subnational areas in Korea. Furthermore, QALE and differences in QALE by income were closely associated with neighborhood-level socioeconomic characteristics.

Breast cancer screening disparities between women with and without disabilities: A national database study in South Korea.

BACKGROUND: Health disparities among individuals with disabilities remain underrecognized. The objective of the current study was to investigate: 1) whether disparities exist in breast cancer screening rates among women with disabilities compared with women without disabilities; 2) whether breast cancer screening rates vary according to the type and severity of disabilities; and 3) trends in breast cancer screening disparities according to disability status over time. METHODS: Using national administrative databases concerning disability status and national cancer screening programs in Korea, age-standardized participation rates were calculated according to the type and severity of disabilities. RESULTS: The age-standardized rate for breast cancer screening in individuals with disabilities increased from 30.2% in 2006 to 53.7% in 2015 (change of +23.5%), whereas that among those without a disability increased from 29.3% to 60.1% (change of +30.8%). In general, disability was associated with slightly lower breast cancer screening rates (adjusted odds ratio [aOR], 0.824; 95% CI, 0.820-0.828). However, screening rates were especially low in women with severe disabilities (aOR, 0.465; 95% CI, 0.461-0.469) and among women with autism (aOR, 0.235; 95% CI, 0.143-0.388), renal failure (aOR, 0.342; 95% CI, 0.337-0.348), brain injury (aOR, 0.349; 95% CI, 0.346-0.352), intellectual disabilities (aOR, 0.403; 95% CI, 0.397-0.410), mental disorders (aOR, 0.494; 95% CI, 0.488-0.501), or ostomies (aOR, 0.529; 95% CI, 0.512-0.546). CONCLUSIONS: Even without a cost barrier, significant disparities were found in breast cancer screening participation, especially in women with severe disabilities and brain-related and/or mental disabilities. Policy efforts, such as ensuring the accessibility of information and equipment, transportation support, and access to a usual source of care, should be made to decrease this disparity.

Prunus serrulata var. spontanea inhibits mast cell activation and mast cell-mediated anaphylaxis.

ETHNOPHARMACOLOGICAL RELEVANCE: A promising approach to treat a variety of diseases are considered as complementary and alternative herbal medicines. Prunus serrulata var. spontanea L. (Rosaceae) is used as herbal medicine to treat allergic diseases according to the Donguibogam, a tradition medical book of the Joseon Dynasty in Korea. AIM OF THE STUDY: We prepared the aqueous extract of the bark of P. serrulata (AEBPS) and aimed to investigate the effects in mouse anaphylaxis models and various types of mast cells, including RBL-2H3, primary cultured peritoneal and bone marrow-derived mast cells. MATERIALS AND METHODS: We used ovalbumin (OVA)-induced active systemic anaphylaxis (ASA) and immunoglobulin (Ig) E-mediated passive cutaneous anaphylaxis (PCA) models, in vivo. The control drug dexamethasone (10 mg/kg) was used to compare the effectiveness of AEBPS (1-100 mg/kg). In vitro, IgE-stimulated mast cells were used to confirm the role of AEBPS (1-100 µg/mL). For statistical analyses, p values less than 0.05 were considered to be significant. RESULTS: In ASA model, oral administration of AEBPS suppressed the hypothermia and increased level of serum histamine in a dose-dependent manner. AEBPS attenuated the serum IgE, OVA-specific IgE, and interleukin (IL)-4. Oral administration of AEBPS also blocked mast cell-dependent PCA. AEBPS suppressed degranulation of mast cells by reducing intracellular calcium level in mast cells. AEBPS inhibited tumor necrosis factor-α and IL-4 expression and secretion in a concentration-dependent manner through the reduction of nuclear factor-κB. CONCLUSIONS: On the basis of these findings, AEBPS could serve as a potential therapeutic target for the management of mast cell-mediated allergic inflammation and as a regulator of mast cell activation.

The Effect of Disability on the Diagnosis and Treatment of Multiple Myeloma in Korea: A National Cohort Study.

PURPOSE: This study aimed to determine whether the diagnosis, treatment approach, and prognosis of multiple myeloma (MM) vary according to the presence and type of disability. Materials and Methods: Demographic, socioeconomic, and medical data were obtained from the National Disability Database, the Korean Central Cancer Registry, and the Korean National Health Insurance claims database. An age- and sex-matched cohort was established using a 1:3 ratio constituted with 2,776,450 people with disabilities and 8,329,350 people without disabilities. Adult patients diagnosed with MM were subsequently selected from this cohort. Disabilities were categorized as physical, communication, intellectual or psychological, and affecting the major internal organs. RESULTS: The cohort included 4,090 patients with MM, with a significantly lower rate per 100,000 persons among people with disabilities than among people without disabilities (29.1 vs. 39.4, p < 0.001). People with disabilities were more likely to undergo dialysis treatment at the time of diagnosis (16.3% vs. 10.0%, p < 0.001), but were less likely to undergo autologous stem cell transplantation (37.5% vs. 43.7%, p=0.072). This trend was more evident among patients with intellectual or psychological disabilities. The median overall survival among patients with disabilities was significantly shorter than that among patients without disabilities (36.8 months vs. 51.2 months, p < 0.001). CONCLUSION: In Korea, people with disabilities generally have a lower rate of MM diagnosis, receive less intensive treatment, and have a lower survival rate than people without disabilities.

Cynanchum atratum Ameliorates Airway Inflammation via Maintaining Alveolar Barrier and Regulating Mast Cell-Mediated Inflammatory Responses.

Asthma is a common allergic airway inflammatory disease, characterized by abnormal breathing due to bronchial inflammation. Asthma aggravates the patient's quality of life and needs continuous pharmacological treatment. Therefore, discovery of drugs for the treatment of asthma is an important area of human health. The aim of the present study was to evaluate whether Cynanchum atratum extract (CAE) modulates the asthma-like allergic airway inflammation and to study its possible mechanism of action using ovalbumin (OVA)-induced airway inflammation and lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice, as well as a mast cell-based in vitro model. The histological analysis showed that CAE reduced the airway constriction and immune cell infiltration. CAE also inhibited release of ß-hexosaminidase and expression of inflammatory cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-4, and IL-5 in bronchoalveolar lavage fluid and lung tissues. In addition, CAE reduced the OVA-specific immunoglobulin (Ig) E, total IgE, IgG1, and IgG2a levels in the serum. In the LPS-induced ALI model, CAE suppressed the LPS-induced lung barrier dysfunction and the release of proinflammatory cytokines. Because allergic airway inflammatory responses are associated with the activation of mast cells, RBL-2H3 cells were used to evaluate the underlying mechanism of CAE effects. In RBL-2H3 cells, CAE down-regulated release of ß-hexosaminidase and histamine by reducing the intracellular calcium influx. In addition, CAE suppressed the expression of proinflammatory cytokines by inhibiting nuclear translocation of nuclear factor-κB. Taken together, our findings suggest that CAE may help in the prevention or treatment of airway inflammatory diseases.

Family tree database of the National Health Information Database in Korea.

We constructed the family tree database (DB) by using a new family code system that can logically express interpersonal family relationships and by comparing and complementing health insurance eligibility data and resident register data of the National Health Information Database (NHID). In the family tree DB, Parents and grandparents are matched for more than 95% of those who were born between 2010 and 2017. Codes for inverse relationships and extended relationships are generated using sequences of the three-digit basic family codes. The family tree DB contains variables such as sex, birth year, family relations, and degree of kinship (maximum of 4) between subjects and family members. Using the family tree DB, we find that prevalence rates of hypertension, diabetes, ischemic heart disease, cerebrovascular disease, and cancer are higher for those with family history. The family tree DB may omit some relationships due to incomplete past data, and some family relations cannot be uniquely determined because the source data only contain relationships between head and members of the household. The family tree DB is a part of the NHID, and researchers can submit requests for data on the website at http://nhiss.nhis.or.kr. Requested data will be provided after approval from the data service review board. However, the family tree DB can be limitedly provided for studies with high public value in order to maximize personal information protection.

Interactions of Behavioral Changes in Smoking, High-risk Drinking, and Weight Gain in a Population of 7.2 Million in Korea.

OBJECTIVES: To identify simultaneous behavioral changes in alcohol consumption, smoking, and weight using a fixed-effect model and to characterize their associations with disease status. METHODS: This study included 7 000 529 individuals who participated in the national biennial health-screening program every 2 years from 2009 to 2016 and were aged 40 or more. We reconstructed the data into an individual-level panel dataset with 4 waves. We used a fixed-effect model for smoking, heavy alcohol drinking, and overweight. The independent variables were sex, age, lifestyle factors, insurance contribution, employment status, and disease status. RESULTS: Becoming a high-risk drinker and losing weight were associated with initiation or resumption of smoking. Initiation or resumption of smoking and weight gain were associated with non-high-risk drinkers becoming high-risk drinkers. Smoking cessation and becoming a high-risk drinker were associated with normal-weight participants becoming overweight. Participants with newly acquired diabetes mellitus, ischemic heart disease, stroke, and cancer tended to stop smoking, discontinue high-risk drinking, and return to a normal weight. CONCLUSIONS: These results obtained using a large-scale population-based database documented interactions among lifestyle factors over time.

Cohort Profile: National health insurance service-senior (NHIS-senior) cohort in Korea.

PURPOSE: The National Health Insurance Service (NHIS)-Senior was set up to provide high-quality longitudinal data that can be used to explore various aspects of changes in the socio-economical and health status of older adults, to predict risk factors and to investigate their health outcomes. PARTICIPANTS: The NHIS-Senior cohort, a Korean nationwide retrospective administrative data cohort, is composed of older adults aged 60 years and over in 2002. It consists of 558 147 people selected by 10% simple random sampling method from a total of 5.5 million subjects aged 60+ in the National Health Information Database. The cohort was followed up through 2015 for all subjects, except for those who were deceased. FINDINGS TO DATE: The healthcare utilisation and admission rates were the highest for acute upper respiratory infections and influenza (75.2%). The age-standardised (defined with reference to the world standard population) mortality rate for 10 years (through 2012) was 4333 per 100 000 person-years. Malignant neoplasms were the most common cause of death in both sexes (1032.1 per 100 000 person-years for men, 376.7 per 100 000 person-years for women). A total of 34 483 individuals applied for long-term care service in 2008, of whom 17.9% were assessed as grade 1, meaning that they were completely dependent on the help of another person to live daily life. FUTURE PLANS: The data are provided for the purposes of policy and academic research under the Act on Promotion of the Provision and Use of Public Data in Korea. The NHIS-Senior cohort data are only available for Korean researchers at the moment, but it is possible for researchers outside the country to gain access to the data by conducting a joint study with a Korean researcher. The cohort will be maintained and continuously updated by the NHIS.

Use of the National Health Information Database for Estimating Town-Level Mortality in Korea: Comparison with the National Administrative Data, 2014-2017.

BACKGROUND: This study addressed town-level mortality rates using the National Health Information Database (NHID) of the National Health Insurance Service in Korea in comparison with those derived from the National Administrative Data (NAD) of the Ministry of Interior and Safety. METHODS: We employed the NHID and NAD between 2014 and 2017. We compared the numbers of population and deaths at the national level between these two data sets. We also compared the distribution of the town-level numbers of population and deaths of the two data sets. Correlation analyses were performed to investigate the relation between the NHID and NAD in the town-level numbers of population and deaths, crude mortality rate, and standardized mortality ratio (SMR). RESULTS: The numbers of population and deaths in the NHID were almost identical to those in the NAD, regardless of gender. The distribution of the town-level numbers of population and deaths was also similar between the two data sets during the entire study period. Throughout the study period, the Pearson correlation coefficients between the two databases for the town-level numbers of population and deaths and the crude mortality rate were 0.996 or over. The correlation coefficients for the SMR ranged from 0.937 to 0.972. CONCLUSION: Town-level mortality showed significant correlation and concordance between the NHID and NAD. This result highlights the possibility of producing future analyses of town-level health-related indicators in Korea, including the mortality rate, using the NHID.

Provider factors influencing prescriptions of recommended antihypertensive medications among patients with diabetes and hypertension
.

OBJECTIVE: Managing hypertension to prevent complications in patients with diabetes requires appropriate pharmacotherapy. This study aimed to analyze healthcare provider factors influencing prescriptions of angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs) as the first-line therapy in managing hypertension among patients with diabetes in primary care. MATERIALS: This study used National Health Insurance Claims Data in Korea. METHODS: We calculated the prescription rate of angiotensin-converting enzyme inhibitors (ACE inhibitors) or ARBs by dividing the number of patients prescribed an ACE inhibitor or an ARB by the number of patients with diabetes prescribed hypoglycemic agents and antihypertensive agents. We performed a logistic regression to investigate the factors influencing the prescription rate of ACE inhibitors or ARBs. RESULTS: The mean prescription rate of ACE inhibitors or ARBs was 69.8%. The prescription rate of ACE inhibitors or ARBs decreased with increasing physician and patient age. The rate was higher for male patients than for females. The rate was higher in institutions with a greater number of physicians and among internists than among general practitioners, surgery-related and internal medicine-related specialists. The rate was significantly influenced by the mean monthly number of patients with hypertension per medical institution, the number of physicians per medical institution, and the physician's age and specialty. CONCLUSION: The age and specialty of the prescribing physician influenced the use of ACE inhibitors or ARBs in patients with diabetes and hypertension in primary care. Efforts are needed to promote information exchange among physicians and the appropriate prescriptions of antihypertensive agents in patients with diabetes and hypertension in primary care.

Cancer risk among young men with weight gain after smoking cessation: A population-based cohort study.

BACKGROUND: Smoking cessation may help the current smokers to reduce cancer risk. However, weight gain following smoking cessation may attenuate the protective association of cessation with cancer. PATIENTS AND METHODS: Our study included 1,278,794 men who were aged 20-39 years and underwent two consecutive health examinations by the National Health Insurance Service, without previous diagnosis of cancer. Participants were categorized into continual smokers, quitters with different degree of body weight change, and never smokers based on the biennial national health screening program (2002-2003 and 2004-2005) and were followed from January 1, 2006 to December 31, 2015. Cox proportional hazard models and restricted cubic spline model was used to evaluate the association of post-cessation weight change and cancer risk after adjustment for potential confounders. RESULTS: During the 10 years of follow-up, the analyses included 1,278,794 men with 21,494 cancer incidences. Compared to continual smokers, quitters without weight gain of 2.0 kg had significantly lower risk of obesity-related cancer (hazard ratio [HR], 0.88; 95% confidence interval [CI], 0.79-0.97), smoking-related cancer (HR, 0.90; 95% CI, 0.83 to 0.98), and gastrointestinal cancer (HR, 89; 95% CI, 0.80 to 0.98). Weight gain among quitters attenuated the risk reduction of cancer compared to continual smoking. Among quitters, weight gain up to 5.0 kg with smoking cessation showed protective association with cancer risk among quitters without weight gain. CONCLUSION: Excessive weight gain with smoking cessation among quitters was not associated with reduced risk of several cancer types. This association should be taken into account when recommending smoking cessation to prevent cancer.