Statistics Korea Research Articles

Association between nut consumption and mortality risk: a 20-year cohort study in Korea with a stratified analysis by health-related variables.

Although nuts are a well-known healthy food group, the relationship between nut consumption and mortality remains unclear, particularly among Asians. This prospective cohort study examined the association between nut consumption and the risk of all-cause, cardiovascular disease (CVD), and cancer mortality in Korean adults. Data from two cohorts (the Ansan-Ansung and Health-Examinees) from the Korean Genome and Epidemiology Study were used. A total of 114,140 individuals aged 40-79 years were included in the data analyses. Nut consumption was assessed using a validated semi-quantitative food frequency questionnaire and categorized into four groups: non-consumers, less than 1 serving/week, 1-2 servings/week, and 2 or more servings/week (one serving was 15g of nuts). Mortality outcomes were determined based on the 2001-2021 death records from Statistics Korea. Cox proportional hazard regression analysis was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality across nut consumption categories. A stratified subgroup analysis by health-related variables was also performed. During a mean follow-up of 12.3 years, 4,559 deaths were recorded. After adjusting for covariates, the HR for all-cause mortality was 0.877 (95% CI = 0.772-0.996, p for trend = 0.006) in individuals with a nut consumption of 2 or more servings/week compared with that in non-consumers. Multivariable HRs for CVD mortality were 0.800 (95% CI = 0.681-0.939) in individuals consuming less than 1 serving/week, 0.656 (95% CI = 0.469-0.918) in those consuming 1-2 servings/week, and 1.009 (95% CI = 0.756-1.347) in those consuming 2 or more servings/week compared with that in non-consumers (p for trend = 0.080). No association was observed between nut consumption and cancer mortality. Stratified analysis identified significant interactions in the association between nut consumption and all-cause mortality by age, body mass index, and physical activity. Nut consumption was linearly associated with the reduced risk of all-cause mortality and showed a non-linear dose-response relationship with CVD mortality in Koreans, but had no association with cancer mortality. The effects of nut consumption, which have been inadequately investigated in this population, varied across different subgroups. These findings suggest that incorporating nuts into the diet should be encouraged for long-term health of Korean adults.

Incidence and Influencing Factors of Avoidable Mortality in South Korea from 2013-2022: Analysis of Cause-of-Death Statistics.

This study aimed to identify trends in avoidable mortality (AVM) in 16 provincial and metropolitan regions of South Korea and determine the factors influencing AVM. First, the AVM rate (AVMR) was calculated using the Statistics Korea cause-of-death and population data by age and region from 2013 to 2022. Second, a health determinants model was built, and we identified the factors influencing AVM using generalized estimating equations analysis. Although the AVMR per 100,000 people displayed a steadily decreasing trend from 2013 to 2020, it began to increase in 2021. Meanwhile, Jeonnam, Jeonbuk, Gyeongnam, Gyeongbuk, Chungnam, Chungbuk, and Gangwon Provinces showed a higher AVMR than the national average. The analysis revealed that each 1-unit increase in the older adult population, smoking, perceived stress, or nonlocal medical utilization was associated with an increase in the AVMR. Conversely, 1-unit increases in the male-to-female ratio, marriage rate, positive self-rated health, local medical utilization, doctor population, influenza vaccination rate, cancer screening rate, or financial independence were associated with decrease in the AVMR. This study established that the AVMR, which had been continuously decreasing across the 16 regions, shifted to an increasing trend in 2021. We also identified several factors influencing AVM. Further studies are needed to confirm the reasons for this shift in the AVMR and explore the factors that influence AVM across Korea's 16 provincial and metropolitan regions.

Characteristics of the Factors of Associated with Death in Older Adults due to Dementia: Focusing on the Chungbuk Region

Objectives: The purpose of this study is to analyze the characteristics of the factors associated with death due to dementia among the older adults in Chungbuk.Methods: A total of 1,685 the older adults aged 65 years or older who died of dementia in Chungbuk were selected as subjects for the study using raw data on the causes of death for the last five years (2018-2022) from Statistics Korea. Statistical analysis was conducted using frequency analysis and multinomial logistic regression analysis.Results: The mortality rate of dementia among the older adults aged 65 and older in Chungbuk was 3.5%, lower than the national average. There were 147 female deaths per 100,000 population, more than 87 male deaths, and by age, 1,367 were in their 90s and older, 269 were in their 80s, and 22 were in their 70s and younger (65-79). The place of death was 68.5% in medical institutions and 22.4% in social welfare facilities. Alzheimer’s disease was the most common type of dementia causing death (67.0%). The highest number of older adults with dementia died in November, and the lowest in August and September. The highest number of dementia deaths occurred on the 19th, and the lowest on the 29th and 31st, with a difference of 29 deaths. The highest number of deaths occurred at 8:00 a.m. with 102 deaths and the lowest at 2:00 a.m. with 47 deaths. Female gender and type of dementia were significantly associated with dementia death among those aged 70 and younger compared to those aged 90 and older, and female gender and place of death in a medical institution were associated with dementia death among those aged 80 and older.Conclusions: Based on this study, it is recommended to establish a policy to promote mental health in Chungbuk.

기업가적 지향성과 경영성과 간 관계: 기업 수명주기 단계별 차이 분석

This study empirically analyzes the impact of the managerial environment, CEO's vision and strategy, and organizational management system on entrepreneurial orientation in domestic companies, as well as the relationship between entrepreneurial orientation and business performance. Additionally, it examines how these relationships differ across various stages of the corporate life cycle. The analysis utilizes data from the 2022 Entrepreneurial Activity Survey (Company Edition) conducted by the Korea Youth Entrepreneurship Foundation, designated as official statistics by Statistics Korea, which surveyed 3,120 companies. The results of the empirical analysis are as follows First, business environment, vision and strategy are significantly positively related to entrepreneurial orientation. In terms of firm life cycle, we find that firms in the start-up phase are slightly more sensitive to the business environment, while vision and strategy are important regardless of firm life cycle. Second, the operating system of the firm does not have a statistically significant effect on entrepreneurial orientation, and the hypothesis is rejected. It seems that it is important to have an operating system in place from the start-up stage in terms of the business life cycle. Third, a significant positive relationship was found between entrepreneurial orientation and managerial performance, and entrepreneurial orientation had a positive impact on managerial performance regardless of the firm's life cycle. The results of this study expand the factors influencing entrepreneurial orientation and provide theoretical and policy insights by analyzing the corporate life cycle, which is rarely addressed in the field of entrepreneurship, by distinguishing between the startup phase and other phases.

Source Attribution of Health Burdens From Ambient PM2.5, O3, and NO2 Exposure for Assessment of South Korean National Emission Control Scenarios by 2050.

We quantify anthropogenic sources of health burdens associated with ambient air pollution exposure in South Korea and forecast future health burdens using domestic emission control scenarios by 2050 provided by the United Nations Environment Programme (UNEP). Our health burden estimation framework uses GEOS-Chem simulations, satellite-derived NO2, and ground-based observations of PM2.5, O3, and NO2. We estimate 19,000, 3,300, and 8,500 premature deaths owing to long-term exposure to PM2.5, O3, and NO2, respectively, and 23,000 NO2-associated childhood asthma incidences in 2016. Next, we calculate anthropogenic emission contributions to these four health burdens from each species and grid cell using adjoint sensitivity analysis. Domestic sources account for 56%, 38%, 87%, and 88% of marginal emission contributions to the PM2.5-, O3-, and NO2-associated premature deaths and the NO2-associated childhood asthma incidences, respectively. We project health burdens to 2050 using UNEP domestic emission scenarios (Baseline and Mitigation) and population forecasts from Statistics Korea. Because of population aging alone, there are 41,000, 10,000, and 20,000 more premature deaths associated with PM2.5, O3, and NO2 exposure, respectively, and 9,000 fewer childhood asthma incidences associated with NO2. The Mitigation scenario doubles the NO2-associated health benefits over the Baseline scenario, preventing 24,000 premature deaths and 13,000 childhood asthma incidences by 2050. It also slightly reduces PM2.5- and O3-associated premature deaths by 9.9% and 7.0%, unlike the Baseline scenario where these pollutants increase. Furthermore, we examine foreign emission impacts from nine SSP/RCP-based scenarios, highlighting the need for international cooperation to reduce PM2.5 and O3 pollution.

이주배경 독거청년노동자의 한국생활만족도에 영향을 미치는 요인분석

The purpose of this study is to examine factors that affect the satisfaction with life in Korea among young migrant workers living alone. To do this, this study used the 2022 Survey on Immigrant’s Living Conditions and Labour Force data conducted by Statistics Korea and Ministry of Justice. The sample consisted of 2,138 young migrant worker living alone between the ages of 15 and 39. The data were subjected to descriptive statistical analysis, T-test, one-way ANOVA, correlation analysis and hierarchical regression analysis using the SPSS 26.0 statistical program. The main results of this study are as follows: First, satisfaction with life in Korea was correlated with Korean language proficiency level, subjective health status, discrimination experience, and crisis helper. Second, ultimately factors affecting life satisfaction in Korea included subjective health status, experience discrimination, and crisis helper, excluding Korean language proficiency level. Based on those study results, this study discussed practical and policy implications for enhancing the satisfaction with life in Korea among young migrant workers living alone.

Association of physical activity and socio-economic status on mortality in older adults: a retrospective cohort study of KNHANES-mortality linked data

We examined the joint association of physical activity (PA) and socio-economic status (SES) on all-causes and cardiovascular disease (CVD) mortality in 6945 elderly Koreans (mean age: 71.6 years, 41.8% male) using data from the Korean National Health and Nutrition Examination Survey (2007–2013) and death data from Statistics Korea (2019). The SES included household income and education level. PA was assessed using the IPAQ and categorized according to the 2018 PA Guidelines. In stratified analyses using Cox proportional hazards by SES adherence to PA guidelines those who low household income group was associated with a reduced risk of all-cause mortality and CVD mortality, while in the lowest educational level group, it was associated with a reduced risk of all-cause mortality and CVD mortality. In the joint analysis, PA was associated with a significant reduction in all-cause mortality in all groups when compared with those who did not meet PA those who had the lowest SES. However, PA with CVD mortality risk was not significantly associated in the ‘upper-middle’ income and ‘high school’ education groups. The study revealed that PA significantly association mortality, particularly among older adults with low SES. This finding suggests the potential for targeted government interventions to promote healthy aging.

Financial Policies for Single-Person Household Housing in South Korea

We investigated the determinants of awareness, utilization, and satisfaction regarding financial aid programs for single-person households in South Korea and proposed policy enhancements. Our analysis employed logistic regression on microdata from the “2020 Housing Survey” by Statistics Korea, covering the nation and all age groups. We categorized single-person household traits affecting program awareness, utilization, and satisfaction into demographic, socio-economic, housing, and housing perception factors. The dependent variables included awareness, utilization status, and satisfaction levels of government-sponsored financial support programs, which were measured on a four-point Likert scale. The independent variables encompassed demographic, socio-economic, and housing characteristics, which were analyzed comprehensively. We identified factors that influenced awareness, utilization, and satisfaction and recommended tailored policy measures. The findings revealed lower awareness among elderly individuals, women, rural residents, and rental households. Moreover, older age, lower income, rental, and one-room dwelling households exhibited lower utilization rates, with decreased housing and residential environment satisfaction correlating with diminished program satisfaction. Due to the diverse characteristics of single-person households, strategic interventions are crucial. Measures to bridge information gaps, establish comprehensive long-term support systems, and develop differentiated policies tailored to single-person household traits are imperative for improving financial aid programs for this demographic.

Data Resource Profile: The Cancer Public Library Database in South Korea.

This paper provides a comprehensive overview of the Cancer Public Library Database (CPLD), established under the Korean Clinical Data Utilization for Research Excellence project (K-CURE). The CPLD links data from four major population-based public sources: the Korea National Cancer Incidence Database in the Korea Central Cancer Registry, cause-of-death data in Statistics Korea, the National Health Information Database in the National Health Insurance Service, and the National Health Insurance Research Database in the Health Insurance Review & Assessment Service. These databases are linked using an encrypted resident registration number. The CPLD, established in 2022 and updated annually, comprises 1,983,499 men and women newly diagnosed with cancer between 2012 and 2019. It contains data on cancer registration and death, demographics, medical claims, general health checkups, and national cancer screening. The most common cancers among men in the CPLD were stomach (16.1%), lung (14.0%), colorectal (13.3%), prostate (9.6%), and liver (9.3%) cancers. The most common cancers among women were thyroid (20.4%), breast (16.6%), colorectal (9.0%), stomach (7.8%), and lung (6.2%) cancers. Among them, 571,285 died between 2012 and 2020 owing to cancer (89.2%) or other causes (10.8%). Upon approval, the CPLD is accessible to researchers through the K-CURE portal. The CPLD is a unique resource for diverse cancer research to investigate medical use before a cancer diagnosis, during initial diagnosis and treatment, and long-term follow-up. This offers expanded insight into healthcare delivery across the cancer continuum, from screening to end-of-life care.

Cancer Statistics in Korea: Incidence, Mortality, Survival, and Prevalence in 2021.

The current study provides national cancer statistics and their secular trends in Korea, including incidence, mortality, survival, and prevalence in 2021. Incidence, survival, and prevalence rates of cancer were calculated using the Korea National Cancer Incidence Database, from 1999 to 2021, with survival follow-up until December 31, 2022. Deaths from cancer were assessed using causes-of-death data obtained from Statistics Korea. The number of new cancer diagnoses in 2021 increased by 27,002 cases (10.8%) compared to 2020. In 2021, newly diagnosed cancer cases and deaths from cancer were reported as 277,523 (age-standardized rate [ASR], 289.3 per 100,000) and 82,688 (ASR, 67.6 per 100,000), respectively. The overall cancer incidence rates increased by 3.3% annually from 1999 to 2012, and decreased by 5.3% from 2012 to 2015, thereafter, followed by non-significant changes. Cancer mortality rates have been decreasing since 2002, with more rapid decline in recent years (annual decrease of 2.8% from 2002 to 2013; 3.2% from 2013 to 2021). The 5-year relative survival between 2017 and 2021 was 72.1%, which contributed to prevalent cases reaching over 2.4 million in 2021. In 2021, the number of newly diagnosed cancer patients increased as healthcare utilization recovered from the coronavirus disease 2019-related declines of 2020. Revised cancer registration guidelines expanded the registration scope, particularly for stomach and colorectal cancer. Survival rates have improved over the years, leading to a growing population of cancer survivors, necessitating a comprehensive cancer control strategy. The long-term impact of the pandemic on cancer statistics requires future investigation.

Temporal trend of microenvironmental time-activity patterns of the Seoul population from 2004 to 2022 and its potential impact on exposure assessment.

Time-activity pattern (TAP) is an important parameter for determining personal exposure to environmental pollutants. Changes in TAPs could have significant implications for the alterations in outcomes of exposure assessments. This study aimed to evaluate the Seoul population's long-term change in TAPs, along with variations by sociodemographic group. In 2004, 2009, 2014, and 2019, the Time Use Survey of Statistics Korea collected the TAP information of 4036, 2610, 3337, and 2793 Seoul residents, respectively. In 2022, the TAP information of 4401 Seoul residents was collected for Korean Air Pollutant Exposure (KAPEX) research. The microenvironmental TAP changes in the Seoul population from 2004 to 2022 were assessed based on age, gender, work status, and day type. From 2004 to 2022, Seoul people increasingly spent more time in indoor residences (from 14.8 ± 5.1 h to 15.8 ± 4.5 h) and less time in other indoors (from 7.2 ± 4.5 h to 5.9 ± 4.2 h). Their transit time constantly decreased from 2004 (1.4 ± 1.8 h) to 2022 (1.2 ± 1.3 h), whereas the outdoor time fluctuated throughout the years. From 2004 to 2022, the time of the day spent by Seoul people in residential indoor shifted to later in the morning (2004: 8:30 am; 2022: 9:00 am) and earlier in the evening (2004: 9:30 pm; 2022: 7:00 pm); however, the opposite was true for other indoors (2004: from 8:30 am to 9:30 pm; 2022: from 9:00 am to 7:00 pm) and transits (2004: 7:30-9:30 am and 3:00-8:00 pm; 2022: 7:30-9:00 pm and 5:00-9:00). The time of the day spent in outdoors increased from 2004 to 2019, with a distinct peak observed in 2022 (12:00 pm-2:00 pm). The microenvironmental time trends of adolescents and late-adulthoods differed from those of the other age groups, while those of males differed from females. Also, the microenvironmental time trends of the employed differed from those of the unemployed, and those during weekdays differed from those during weekends. Microenvironmental TAP should be essentially considered to estimate the actual exposure to pollutants. This study demonstrates the Seoul population's long-term changes in TAP throughout the 18 years as the significant parameter in exposure assessment. Notably, the microenvironmental TAPs of Seoul people shifted, with variations across different sociodemographic groups. Previous studies in Korea did not consider the TAP shifts in exposure assessment; this study highlights the importance of aligning TAP data with concurrent environmental pollutant data and emphasizes the need for refined data collection in future exposure assessments.

Prediction of Cancer Incidence and Mortality in Korea, 2024.

This study aimed to report the projected cancer incidence and mortality for the year 2024 to estimate Korea's current cancer burden. Cancer incidence data from 1999 to 2021 were obtained from the Korea National Cancer Incidence Database, and cancer mortality data from 1993 to 2022 were acquired from Statistics Korea. Cancer incidence and mortality were projected by fitting a linear regression model to observed age-specific cancer rates against their respective years and multiplying the projected age-specific rates by the anticipated age-specific population for 2024. A joinpoint regression model was used to determine the year in which the linear trend changed significantly; we only used the data of the latest trend for prediction. In total, 292,221 new cancer cases and 83,770 cancer deaths are expected to occur in Korea in 2024. The most common cancer site is expected to be the thyroid, followed by the colon and rectum, lung, breast, and stomach. These five cancers are expected to represent 55.7% of the overall burden of cancer in Korea. The most common type of cancer leading to death is expected to be lung cancer, followed by liver, colorectal, pancreatic, and stomach cancers. The age-standardized incidence rates for female breast and prostate cancers are estimated to continue to increase. These up-to-date estimates of the cancer burden in Korea could be an important resource for planning and evaluating cancer-control programs.

Association of periodontal disease treatment with mortality in patients with dementia: a population-based retrospective cohort study (2002–2018)

Dementia is one of the leading causes of death worldwide. In this study, we analyzed the association of periodontal treatment with the risk of death in patients with dementia. The analyzed data were obtained by linking the National Health Insurance Corporation claims data between 2002 and 2018 to the Statistics Korea death registry. In total, 1,131,406 patients with dementia aged ≥ 65 years had undergone dental treatment during the study period. Time-dependent Cox proportional hazards model was performed. The mortality rate was approximately 10% among the patients with dementia. The 17-years cumulative survival rates for patients who received periodontal treatment and their untreated counterparts were 83.5% and 71.5%, respectively. The crude hazard ratio of the periodontal group was approximately twice as high as that of the non-periodontal group (1.99; P < 0.001). Furthermore, in the regression model that was adjusted for socio-demographic variables and systematic chronic diseases, the risk of death in the non-periodontal group was approximately 1.83 times higher than that of the periodontal group (P < 0.00). These findings suggest that preventive periodontal treatment may decrease mortality risk in older people with dementia.

COVID-19 vaccine safety: Background incidence rates of anaphylaxis, myocarditis, pericarditis, Guillain-Barré Syndrome, and mortality in South Korea using a nationwide population-based cohort study.

To properly assess an association between vaccines and specific adverse events requires a comparison between the observed and background rates; however, studies in South Korea are currently limited. Therefore, in this study, we estimated the background incidence of anaphylaxis, myocarditis, pericarditis, Guillain-Barré syndrome (GBS), and mortality in South Korea. A retrospective cohort study was conducted using the National Sample Cohort (NSC) data. Using NSC, the background incidence rate was estimated by dividing the number of episodes during 2009-2019 by the total population by year and then multiplying by 100,000. Using Statistics Korea data, the background mortality rate was estimated by dividing the number of deaths, during 2009-2019 by the standard population for that year and then multiplying by 100,000. Using background mortality rates, we predicted mortality rates for 2021 using autoregressive integrated moving average models. Further, the expected mortality rates were compared with observed mortality rates. The age-adjusted incidence rate (AIR) of anaphylaxis increased from 4.28 to 22.90 cases per 100,000 population (p = 0.003); myocarditis showed no significant increase, changing from 0.56 to 1.26 cases per 100,000 population (p = 0.276); pericarditis increased from 0.94 to 1.88 cases per 100,000 population (p = 0.005); and GBS increased from 0.78 to 1.21 cases per 100,000 population (p = 0.013). The age-adjusted mortality rate decreased from 645.24 to 475.70 deaths per 100,000 population (p <0.001). The 2021 observed/expected mortality rates for overall (ratio: 1.08, 95% confidence interval [CI]: 1.07-1.08), men (ratio: 1.07, 95% CI: 1.07-1.08), and women (ratio: 1.08, 95% CI: 1.07-1.09), were all significantly higher. When stratified by age group, those aged ≥80 (ratio: 1.16, 95% CI: 1.15-1.17), 60-69 (ratio: 1.11, 95% CI: 1.10-1.13), and 20-29 years old (ratio: 1.07, 95% CI: 1.02-1.13) were also significantly higher. Through the estimation of background rates related to anaphylaxis, myocarditis, pericarditis, GBS, and mortality, we established a reference point for evaluating the potential excess occurrence of adverse events following COVID-19 vaccination. This reference point serves as substantive evidence supporting the safety profile of COVID-19 vaccines.

Extrahepatic Malignancies Are the Leading Cause of Death in Patients with Chronic Hepatitis B without Cirrhosis: A Large Population-Based Cohort Study.

(1) Background: Accurate statistics on the causes of death in patients with chronic hepatitis B (CHB) are lacking. We investigated mortality rates and causes of death over time. (2) Methods: Data on patients newly diagnosed with CHB from 2007 to 2010 (cohort 1, n = 223,424) and 2012 to 2015 (cohort 2, n = 177,966) were retrieved from the Korean National Health Insurance Service. Mortality data were obtained from Statistics Korea. The causes of death were classified as liver-related (hepatic decompensation or hepatocellular carcinoma [HCC]) or extrahepatic (cardiovascular-related, cerebrovascular-related, or extrahepatic malignancy-related). (3) Results: Over a 10-year follow-up period of 223,424 patients (cohort 1) with CHB, the overall mortality was 1.54 per 100 person-years. The mortality associated with HCC was the highest (0.65 per 100 person-years), followed by mortality related to extrahepatic malignancies (0.26 per 100 person-years), and cardio/cerebrovascular diseases (0.18 per 100 person-years). In the non-cirrhotic CHB (87.4%), 70% (11,198/15,996) of patients died due to non-liver-related causes over ten years. The 10-year overall mortality was 0.86 per 100 person-years. Among these, mortality due to extrahepatic malignancies had the highest rate (0.23 per 100 person-years), followed by mortality related to HCC (0.20 per 100 person-years), and cardio/cerebrovascular diseases (0.16 per 100 person-years). The 5-year mortality associated with extrahepatic malignancies increased from 0.36 per 100 person-years (cohort 1) to 0.40 per 100 person-years (cohort 2). (4) Conclusions: Mortality related to HCC decreased, whereas mortality related to extrahepatic malignancies increased in the antiviral era. Extrahepatic malignancies were the leading cause of death among patients with CHB without cirrhosis.

Relationship between metformin use and mortality in tuberculosis patients with diabetes: a nationwide cohort study.

To determine whether metformin, which is considered a host-directed therapy for tuberculosis (TB), is effective in improving the prognosis of patients with TB and diabetes mellitus (DM), who have higher mortality than those without DM. This cohort study included patients who were registered as having TB in the National Tuberculosis Surveillance System. The medical and death records of matched patients were obtained from the National Health Information Database and Statistics Korea, respectively, and data from 2011 to 2017 were collected retrospectively. We classified patients according to metformin use among participants who used diabetes drugs for more than 28 days. The primary outcome was all-cause mortality during TB treatment. Double propensity score adjustment was applied to reduce the effects of confounding and multivariable Cox proportional hazard models were used to estimate adjusted hazard ratio (aHR) with 95% confidence interval (CI). The all-cause mortality rate during TB treatment was lower (9.5% vs. 12.4%, p < 0.01) in the metformin user group. The hazard of death due to all causes after double propensity score adjustment was also lower in the metformin user group (aHR 0.76, 95% CI 0.67-0.86, p < 0.01). There was no significant difference in mortality between metformin users and non-users for TB-related deaths (p = 0.22); however, there was a significant difference in the non-TB-related deaths (p < 0.01). Metformin use in patients with TB-DM co-prevalence is associated with reduced all-cause mortality, suggesting the potential for metformin adjuvant therapy in these patients.

A Quasi-experimental Study on the Effect of Pre-entry Tuberculosis Screening for Immigrants on Treatment Outcomes in South Korea: A Difference-in-Differences Analysis

ObjectiveThis study ascertains the effects of the pre-entry tuberculosis (TB) screening policy, which was implemented as a strategy for managing TB among immigrants, on the treatment outcomes of immigrants in South Korea.MethodsThis study linked three different datasets from 2013 to 2018, namely (1) Korean National Tuberculosis Surveillance System; (2) National Health Information Database for patients diagnosed with TB with ICD code A15-A19, B90, or U84.3; and (3) Statistics Korea database related to cause of deaths. To identify the effect of the policy, cohorts comprising Korean and immigrant TB patients notified before (January 1, 2013–December 31, 2015) and after (September 1, 2016–December 31, 2018), the implementations of the policy were established. A difference-in-differences (DID) analysis of the treatment success and mortality rates was performed.ResultsData from 100,262 TB patients were included in the analysis (before policy implementation: 1240 immigrants and 65,723 Koreans; after policy implementation: 256 immigrants and 33,043 Koreans). The propensity score matching-DID analysis results showed that the difference in the treatment success rate between immigrants and Koreans decreased significantly, from 16% before to 6% after the policy implementation. The difference in the mortality rate between the two groups decreased from − 3% before to − 1% after the policy implementation; however, this difference was insignificant.ConclusionThe treatment outcomes of immigrant TB patients in South Korea improved after the implementation of the pre-entry active TB screening policy. Future immigrant TB policies should consider establishing active patient support strategies and a healthcare collaboration system between countries.

Estimating Excess Mortality During the COVID-19 Pandemic Between 2020-2022 in Korea.

The persistent coronavirus disease 2019 (COVID-19) pandemic has had direct and indirect effects on mortality, making it essential to analyze excess mortality to fully understand the impact of the pandemic. In this study, we constructed a mathematical model using number of deaths from Statistics Korea and analyzed excess mortality between 2020 and 2022 according to age, sex, and dominant severe acute respiratory syndrome coronavirus 2 variant period. Number of all-cause deaths between 2010 and 2022 were obtained from the annual cause-of-death statistics provided by Statistics Korea. COVID-19 mortality data were acquired from the Korea Disease Control and Prevention Agency. A multivariate linear regression model with seasonal effect, stratified by sex and age, was used to estimate the number of deaths in the absence of COVID-19. The estimated excess mortality rate was calculated. Excess mortality was not significant between January 2020 and October 2021. However, it started to increase monthly from November 2021 and reached its highest point during the omicron-dominant period. Specifically, in March and April 2022, during the omicron BA.1/BA.2-dominant period, the estimated median values for excess mortality were the highest at 17,634 and 11,379, respectively. Both COVID-19-related deaths and excess mortality increased with age. A notable increase in excess mortality was observed in individuals aged ≥ 65 years. In the context of excess mortality per 100,000 population based on the estimated median values in March 2022, the highest numbers were found among males and females aged ≥ 85 years at 1,048 and 910, respectively. This study revealed that the prolonged COVID-19 pandemic coupled with its high transmissibility not only increased COVID-19-related deaths but also had a significant impact on overall mortality rates, especially in the elderly. Therefore, it is crucial to concentrate healthcare resources and services on the elderly and ensure continued access to healthcare services during pandemics. Establishing an excess mortality monitoring system in the early stages of a pandemic is necessary to understand the impact of infectious diseases on mortality and effectively evaluate pandemic response policies.

Development of blood demand prediction model using artificial intelligence based on national public big data.

Modern healthcare systems face challenges related to the stable and sufficient blood supply of blood due to shortages. This study aimed to predict the monthly blood transfusion requirements in medical institutions using an artificial intelligence model based on national open big data related to transfusion. Data regarding blood types and components in Korea from January 2010 to December 2021 were obtained from the Health Insurance Review and Assessment Service and Statistics Korea. The data were collected from a single medical institution. Using the obtained information, predictive models were developed, including eXtreme Gradient Boosting (XGBoost), Light Gradient Boosting Machine (LGBM), and category boosting (CatBoost). An ensemble model was created using these three models. The prediction performance of XGBoost, LGBM, and CatBoost demonstrated a mean absolute error ranging from 14.6657 for AB+ red blood cells (RBCs) to 84.0433 for A+ platelet concentrate (PC) and a root mean squared error ranging from 18.5374 for AB+ RBCs to 118.6245 for B+ PC. The error range was further improved by creating ensemble models, wherein the department requesting blood was the most influential parameter affecting transfusion prediction performance for different blood products and types. Except for the department, the features that affected the prediction performance varied for each product and blood type, including the number of RBC antibody screens, crossmatch, nationwide blood donations, and surgeries. Based on blood-related open big data, the developed blood-demand prediction algorithm can efficiently provide medical facilities with an appropriate volume of blood ahead of time.

Unmet healthcare needs and the local extinction index: an analysis of regional disparities impacting South Korea's older adults.

This study examines the factors affecting unmet healthcare experiences by integrating individual-and community-level extinction indices. Using spatial autocorrelation and multilevel modeling, the study utilizes data from the Community Health Survey and Statistics Korea for 218 local government regions from 2018 to 2019. The analysis identifies significant clustering, particularly in non-metropolitan regions with a higher local extinction index. At the individual level, some factors affect unmet medical needs, and unmet healthcare needs increase as the local extinction index at the community level increases. The findings underscore the need for strategic efforts to enhance regional healthcare accessibility, particularly for vulnerable populations and local infrastructure development.