The cascade of care for latent tuberculosis infection in congregate settings: A national cohort analysis, Korea, 2017-2018.

Background: In 2017, Korea implemented a nationwide project to screen and treat latent tuberculosis infection (LTBI) in high-risk for transmission public congregate settings. We aimed to assess programme success using a cascade of care framework. Materials and methods: We undertook a cohort study of people from three congregate settings screened between March 2017 and December 2018: (1) first-grade high school students, (2) employees of educational institutions, (3) employees of social welfare facilities. We report percentages of participants with LTBI completing each step in the cascade of care model. Poisson regression models were used to determine factors associated with not visiting clinics, not initiating treatment, and not completing treatment. Results: Among the 96,439 participants who had a positive interferon-gamma release assay result, the percentage visiting clinics for further assessment, to initiate treatment, and who then completed treatment were 50.7, 34.7, and 28.9%, respectively. Compared to those aged 20-34 years, individuals aged < 20 years and aged ≥ 65 years were less likely to visit clinics, though more likely to complete treatment once initiated. Using public health centres rather than private hospitals was associated with people "not initiating treatment" (adjusted risk ratio [aRR], 3.72; 95% confidence interval [CI], 3.95-3.86). Nine-month isoniazid monotherapy therapy was associated with "not completing treatment," compared to 3-month isoniazid and rifampin therapy (aRR, 1.28; 95% CI, 1.16-1.41). Conclusion: Among participants with LTBI from three congregate settings, less than one third completed treatment. Age, treatment centre, and initial regimen were important determinants of losses to care through the cascade.

Continuing Quality Assessment Program Improves Clinical Outcomes of Hospitalized Community-Acquired Pneumonia: A Nationwide Cross-Sectional Study in Korea.

BACKGROUND: Pneumonia, which is the third leading cause of death in South Korea, is continuously increasing with the aging society. The Health Insurance Review and Assessment of South Korea conducted a quality assessment (QA) for improving the outcome of community-acquired pneumonia (CAP). METHODS: We conducted a nationwide cross-sectional study of hospitalized CAP in South Korea. First to third QA data were gathered into a single database. The national health insurance database was merged with the QA database for analyzing the medical claims data. Comorbidities, pneumonia severity, and pneumonia care appropriateness were calculated using Charlson comorbidity index (CCI), CURB-65, and core assessment of CAP scores (CAP scores), respectively. RESULTS: Overall, 54,307 patients were enrolled. The CAP scores significantly improved on QA program implementation (P < 0.001). All the variables demonstrated an association with in-hospital mortality, hospital length of stay (LOS), and 30-day mortality in the univariate analyses. Following the adjustments, higher CCI and CURB-65 scores were associated with higher in-hospital mortality, longer hospital LOS, and higher 30-day mortality. Male sex was associated with higher in-hospital/30-day mortality and shorter hospital LOS. Higher CAP scores were associated with shorter hospital LOS (P < 0.001). Upon QA program implementation, in-hospital mortality (P < 0.001), hospital LOS (P < 0.001), and 30-day mortality (P < 0.001) improved. CONCLUSION: Continuing QA program is effective in improving the clinical outcomes of hospitalized CAP.

Prevalence of latent tuberculosis infection among participants of the national LTBI screening program in South Korea - A problem of low coverage rate with current LTBI strategy.

Background: The Government of South Korea launched a national preemptive latent tuberculosis infection (LTBI) screening program in 2016, including more than 1. 6 million population in congregate settings. The objective of this study was to analyze LTBI prevalence and its risk factors in each setting. Additionally, the proportion of LTBI pool covered by the current national LTBI strategy was investigated. Methods: Database for results of interferon gamma release assay (IGRA), X-ray, and baseline demographic information was linked with National Health Information Database, national tuberculosis (TB) surveillance database, and national contact investigation database. Participants were categorized into three groups: Group A, workers of postpartum care centers, social welfare facilities and educational institutions; Group B, first year students in high school and out-of-school youths; and Group C, inmates of correctional facilities. Relative risks of LTBI by sex, age, place of living, income level, and comorbidities were calculated. Results: A total of 444,394 participants in Group A, 272,224 participants in Group B, and 11,511 participants in Group C who participated in the national LTBI screening program between 2017 and 2018 were included, with LTBI prevalence of 20.7, 2.0, and 33.2%, respectively. Age was the single most important risk factor in Group A and Group C. Low-income level was another risk factor commonly identified in all groups. Among participants with positive IGRA results, 2.7, 4.4, and 3.3% in Groups A, B and C, respectively, had past TB exposure history since 2013. Current LTBI guideline targeting high or moderate TB risk disease covered 6.5, 0.6, and 1.1% of participants with positive IGRA results in Groups A, B and C, respectively. Conclusion: Only a small proportion of participants with positive IGRA results could be covered by the current LTBI strategy. Expansion of LTBI strategy by identifying further high-TB risk group in the general population is required.

Differential impact of working hours on unmet medical needs by income level: a longitudinal study of Korean workers.

OBJECTIVES: Unmet medical need is defined as the perceived need for medical service that is not received. Although the association between unmet medical needs and working hours has been explored before, the combined effect of household income has not been investigated thus far. This study, therefore, aimed to examine the differential association between working hours and the risk of unmet medical needs according to household income. METHODS: A total of 7047 participants enrolled in the Korea Health Panel data 2011-2014 were considered. The analytical method used in this study was a generalized estimating equation model that accounted for repeated measured participants. By controlling for time-invariant individual-fixed effects, we identified the relationship between long working hours and the risk of unmet medical needs. RESULTS: The association between long working hours and the risk of unmet medical needs differed according to household income. In the highest quintile of household income, the risk of unmet medical needs was 1.58-fold higher among those who worked >52 hours per week than among those who worked 30-52 hours per week. However, this association was not significant in the lowest quintile group. CONCLUSIONS: The current study implies that financial hardship might be a more fundamental health hazard than working longer hours among the low-income group. Future policies should consider not only limiting working hours but also compensating workers' income to adequately protect low-income workers from the health risks associated with long working hours.

Latent Tuberculosis Infection Screening and Treatment in Congregate Settings (TB FREE COREA): Demographic Profiles of Interferon-Gamma Release Assay Cohort.

In 2017, the Korean government launched an unprecedentedly large-scaled latent tuberculosis infection (LTBI) screening project which covered more than a million individuals in congregate settings. A total of 1,047,689 participants of source population (n = 2,336,157) underwent LTBI testing from 2017 to 2018. The overall LTBI test uptake rate during this project was 44.8%. Workers in daycare centers (83.5%) and kindergartens (78.9%) showed high participation rate. A total of 1,012,206 individuals with valid results of interferon-gamma release assay (IGRA) were selected to constitute the IGRA cohort. Most of the enrolled participants in the IGRA cohort were in their working age. Approximately, three-quarters of total enrolled population were female. Investigating the LTBI prevalence, stages of LTBI care cascade, natural history of LTBI, efficacy of LTBI treatment and cost-effectiveness of LTBI screening are feasible within this IGRA cohort.

Is Educational Level Linked to Unable to Work Due to Ill-health?

BACKGROUND: This study aimed to examine the association between educational level and unable to work due to ill-health (UWdIH) among 30- to 79-year-old South Koreans. METHODS: A cross-sectional nationwide survey of the 2010-2016 Korea National Health and Nutritional Evaluation Survey was used for analyses. A total of 29,930 participants aged ≥30 and < 80 years, who do not have any disability in their daily life because of health problems, were included. Educational level and reason for nonworking are self-reported with multiple choices. Multivariate logistic regression was used to examine an association between education level and UWdIH by setting those who graduated college as their final education (n = 6,997) as a baseline while controlling for potential confounding factors. RESULTS: In the age-stratified result, the ratio of UWdIH was increased as age increases in 3 educational groups (p < .0001). There was a tendency that low-level educated [International Standard Classification of Education (0-2)] participants showed higher ratio of UWdIH than high-level educated [International Standard Classification of Education (5≤)] participants in both sexes (odds ratio: 2.54, 95% confidence interval: 2.12-3.05). CONCLUSION: There is a clear link between educational level and UWdIH; the less the educated, the more likely to be UWdIH. Policy priority should be given to plans that can help this vulnerable social group to work and enjoy healthy lives.

Association between morbidity of non-communicable disease and employment status: a comparison between Korea and the United States.

BACKGROUND: Globally, the prevalence of chronic disease continues to rise and is likely to grow further over the coming decades due to population ageing. Since older age is associated closely with development of chronic disease, it stands to reason that demographic changes will increase the proportion of older workers with chronic disease. The aim of the present study was to determine how chronic diseases affect employment status in Korea and the USA. METHODS: The study was based on National Health and Nutrition Survey data (2007-2014) obtained by the Korean and American Centers for Disease Control and Prevention. A total of 44,693 subjects were categorized into two geographical groups: Korea (29,260 subjects) and the USA (15,433 subjects). A chi-square test was used to compare the groups in terms of socio-demographic factors, health-related factors, and chronic disease. Multivariate logistic regression analysis was conducted to determine the effect of five chronic diseases (hypertension, diabetes, dyslipidemia, cardiovascular disease, and cancer) on employment status. RESULTS: There were 29,260 Korean and 15,433 American respondents. Chronic disease increased the risk of unemployment in Korea markedly (Odds ratio [OR] range, 1.17-2.47). Cardiovascular disease and cancer had the most profound negative effect on Korean unemployment (OR = 2.47 and 2.03, respectively). The risk of unemployment was generally 2-3-fold lower in the USA (OR range, 0.5-1.04). CONCLUSIONS: Chronic disease had a significant impact on economic activity in Korea, but a smaller impact in the USA. This difference may be related to different health insurance schemes and cultural approaches to people with diseases in the two countries. It is important to explore factors that limit economic participation by people with chronic diseases, and to identify social policies that will overcome these factors. Further between-country studies are needed to identify social solutions to the socio-economic burden of chronic illness.

Factors Associated with General Health Screening Participation among Married Immigrant Women in Korea.

Background: The number of married female immigrants living in Korea has been increasing and is expected to increase further. This study was performed to identify factors associated with national general health screening participation among married immigrant women living in South Korea. Methods: The Korean National Health Insurance System's (NHIS) customized database for the years 2014 and 2015 was used. The targets of this study were women aged 19 years old and above. To identify factors associated with national general health screening participation, the following analyses were employed: frequency, chi-square, simple regression, and multiple regression. Results: A total of 11,213 women were identified in the NHIS database. Overall, 67.4% participated in national general health screenings, lower than the 74.6% participation rate of the entire women's health screening program. Married immigrant women with a job had higher health screening participation than those without a job (OR = 2.822, p < 0.0001). Age, socioeconomic status, and duration of stay were related to health screening behaviors among employed married immigrant women. Nationality, socioeconomic status, duration of stay, and disease status were associated with general health screening behaviors among unemployed immigrant women. The odds ratios decreased as the length of stay increased, regardless of employment status. Conclusion: The results of this study showed that employment status and duration of stay in Korea are significantly associated with general health screening participation. Accordingly, to improve awareness about health screening and health care disparities, programs promoting health screening participation for socially vulnerable classes, including immigrant women and unemployed women, should be instigated.

Incidence and costs of cervical intraepithelial neoplasia in the Korean population.

OBJECTIVE: The purpose of this study was to assess the incidence rate of cervical intraepithelial neoplasia (CIN) and cervical cancer, and their costs according to age. METHODS: We collected data on annual incidence and medical costs of CIN and cervical cancer from 2010 until the end of 2014 from the Health Insurance Review and Assessment (HIRA) service. The CIN was classified into CIN3 (high-grade) requiring conization and CIN1/2 (low-grade) requiring observation. RESULTS: Incidence rates of CIN3 and cervical cancer are reducing over time, whereas CIN1/2 is increasing significantly (p for trend: <0.001). The peak ages of incidence were 25-29, 30-34, and 70-74 years old for CIN1/2, CIN3, and cervical cancer, respectively. The crude incidence of CIN1/2 increased by approximately 30% in 2014 compared to 5 years ago and demonstrated an increasing trend in all age groups. The CIN3 showed a significantly increasing trend in the age group of 30-39 years old, the cervical cancer was significantly reduced in all ages, except the 35-39 years old. The treatment for cervical cancer costs $3,342 per year, whereas the treatment for CIN3 and CIN1/2 cost $467 and $83, respectively. CONCLUSION: The crude incidence rate of cervical cancer is currently decreasing among Korean women, but the incidence rates and medical costs of CIN and cervical cancer are increasing in women in their 30s in Korea. These findings suggest that different strategies by age will be required for prevention of cervical cancer in Korea.

Outcomes of Direct Oral Anticoagulants in Patients With Mitral Stenosis.

BACKGROUND: Patients with mitral stenosis and atrial fibrillation (AF) require anticoagulation for stroke prevention. Thus far, all studies on direct oral anticoagulants (DOACs) have excluded patients with moderate to severe mitral stenosis. OBJECTIVES: The aim of this study was to validate the efficacy of DOACs in patients with mitral stenosis. METHODS: The study population was enrolled from the Health Insurance Review and Assessment Service (HIRA) database in the Republic of Korea, and it included patients who were diagnosed with mitral stenosis and AF and either were prescribed DOACs for off-label use or received conventional treatment with warfarin. The primary efficacy endpoint was ischemic strokes or systemic embolisms, and the safety outcome was intracranial hemorrhage. RESULTS: A total of 2,230 patients (mean age 69.7 ± 10.5 years; 682 [30.6%] males) were included in the present study. Thromboembolic events occurred at a rate of 2.22%/year in the DOAC group, and 4.19%/year in the warfarin group (adjusted hazard ratio for DOAC: 0.28; 95% confidence interval: 0.18 to 0.45). Intracranial hemorrhage occurred in 0.49% of the DOAC group and 0.93% of the warfarin group (adjusted hazard ratio for DOAC: 0.53; 95% confidence interval: 0.22 to 1.26). CONCLUSIONS: In patients with AF accompanied with mitral stenosis, DOAC use is promising and hypothesis generating in preventing thromboembolism. Our results need to be replicated in a randomized trial.

Participation inequality in the National General Health Examination based on enterprise size.

BACKGROUND: Health examinations are performed so that diseases can be identified and treated earlier. Several studies have evaluated the determinants of participation in health examinations including cancer screening, but few have evaluated the relationship between the size of the enterprise and their participation in Workers' General Health Examinations (WGHE). The aim of the present study was to estimate the association of WGHE participation with the size of the enterprise and the type of policyholder. METHODS: The eligible population from 2006 through 2013 was extracted from the National Health Insurance Service (NHIS) database. The population size ranged from 14-17 million. After adjustment for age and gender, multiple logistic regression analysis was performed to estimate the odds ratios of participating in the WGHE (by age group) based on the type of policyholder (reference: public officers) and the size of the enterprise (reference: enterprise size ≥300 employees), respectively. RESULTS: Workers employed at enterprises with <50 persons were less likely to participate in WGHEs than those employed at enterprises with ≥300 persons. After policyholders were stratified by type (non-office workers vs. public officers), a disparity in the WGHE participation rate was found between the different types of policyholders at enterprises with <50 employees (reference: those employed at enterprises with ≥300 employees); the odds ratios for subjects in their 40s and 50s were 0.2-0.3 for non-office workers vs. 0.8-2.0 for public officers. CONCLUSION: Workplace policyholders at small enterprises comprised a vulnerable group less likely to participate in WGHEs. Efforts should be made to raise the WGHE participation rate among the vulnerable employees belonging to small enterprises, as well as among their dependents.

The current condition of the workers' general health examination in South Korea: a retrospective study.

BACKGROUND: Business owners in the Republic of Korea must take part in the workers' general health examination. However, there have been few formal analyses of the uptake of this examination by employees. In the present study, we examined the rates of participation in medical examinations according to age group, health insurance type, and enterprise size, and then compared these results with those of the national general health screening. Furthermore, we determined the distribution of patients with abnormal results for diabetes and hypertension, and outlined the significance and history of domestic health examinations. METHODS: We started by comparing participation rates extracted from the among health examination data of the National Health Insurance Service from 2006-2013 by sex, age, insurance type, and enterprise size of workplace health insurance beneficiaries (i.e., those whose insurance is provided by their workplace). In addition, we analyzed the prevalence rates of abnormal results for hypertension and diabetes, and explored the history and significance of health examinations in the Republic of Korea. RESULTS: The overall participation rate in the primary health examination in 2006 was 56%, and this increased to 72% in 2013. However, the rates of the secondary screening did not increase much. Among workplace policyholders (i.e., those whose insurance is provided by their workplace), the participation rates of workers in enterprises with less than 50 employees were lower than were those in enterprises with 50 or more employees. Notably, the rates and odds ratios of patients with abnormal results for diabetes and hypertension were relatively high, particularly among those working in smaller enterprises. CONCLUSIONS: Although the workers' general health examination has been replaced with the national general health screening, it remains necessary to ensure uniform health management services among all workers in the Republic of Korea. This can, in turn, promote occupational health and improve working conditions throughout the Republic of Korea.

The modifying role of caregiver burden on predictors of quality of life of caregivers of hospitalized chronic stroke patients.

BACKGROUND: Caregiver burden is an important predictor of quality of life (QoL) among caregivers of stroke patients. While caregiver burden and QoL might be closely related, caregiver burden seems also to be a potential modifier of the associations between patients' and caregivers' characteristics and caregivers' QoL. OBJECTIVE: The purpose of this study was to investigate the effect of caregiver burden in caregivers of hospitalized chronic stroke patients and the predictors of caregivers' QoL by level of caregiver burden. METHODS: A total of 238 patients and their caregivers were interviewed using questionnaires consisting of the Zarit Burden Interview and the Korean-version of the World Health Organization Quality of Life-BREF. Multiple hierarchical regression analyses were performed to determine the predictors of caregivers' QoL among caregivers stratified by median caregiver burden score (high/low). RESULTS: Caregiver burden had a modifying effect on caregivers' QoL. In caregivers with high burden, the patient characteristics of being unemployed and the caregiver characteristics of poor health status, lower income, and being a spouse were negative predictors of caregivers' QoL. In caregivers with low burden, the patient characteristics of being hospitalized for a longer duration and the caregiver characteristics of poor health status were negative predictors of caregivers' QoL (all ps < 0.05). CONCLUSIONS: This study found that in South Korea, more attention should be paid to spouses who are caring for hospitalized chronic stroke patients, particularly with regard to their health status and financial problems. Further studies are needed to examine the impact of factors not examined in the Korean cultural context.

Weekend work and depressive symptoms among Korean employees.

The purpose of this study was to quantify the association between weekend work and depressive symptoms in a representative sample of Korean employees. Subjects were 29 171 employees of companies in Korea. Data were obtained as part of the 2011 Korean Working Conditions Survey. Depressive symptoms were measured as a score of ≤7 on the World Health Organization Well-being Index. The association between weekend work and depressive symptoms was quantified using logistic regression, controlling for sociodemographic and work-related factors including the number of hours worked per week and stratified by gender. The prevalence of depressive symptoms was higher in employees who reported working at least one weekend day in the past month than in employees who reported working no weekend days in the past month. After controlling for confounders, including the number of hours worked per week, 1-4 days of weekend work in the past month (odds ratio [95% confidence interval] of 1.36 [1.18-1.57] in males and 1.32 [1.12-1.58] in females) and >4 days of weekend work in the past month (odds ratio [95% confidence interval] of 1.45 [1.19-1.78] in males and 1.36 [1.07-1.73] in females) were significantly associated with depressive symptoms. Weekend work was related with a significant increase in the prevalence of depressive symptoms in Korean workers.

Work-related infectious diseases among Korean workers compensated under the Industrial Accident Compensation Insurance Law, 2006-2011.

BACKGROUND: Korea has no surveillance system for work-related infectious disease. However, these diseases are compensated by the Korea Workers' Compensation & Welfare Service (KCOMWEL). OBJECTIVES: To understand the nature and distribution of compensated occupational infectious diseases in Korea. METHODS: We used the KCOMWEL electronic database to analyze compensated cases of work-related occupational infectious disease. We reviewed and confirmed diagnoses excluding denied claims, secondary infections, dermatoid diseases, duplicated cases and those with missing information. We calculated the distribution of work-related infectious disease in Korea by occupation, calendar year, gender, age, and employment duration, as well as the annual compensated claim rates (per million). RESULTS: We included 1,062 compensated cases of work-related infectious disease. The most common was scrub typhus (n = 567, 53.4%), followed by tuberculosis (n = 227, 21.4%), viral hepatitis (n = 55, 5.2%), and viral influenza (n = 53, 5.0%). A sudden increase in scrub typhus was observed in 2009. Unskilled laborers, including short-term contract workers in public sectors, were most commonly affected by these diseases, followed by health care professionals. CONCLUSIONS: Workers employed in forestry care in the public sectors and in hospitals were most vulnerable to infections. Proper surveillance systems to monitor infectious diseases among vulnerable working groups and improved prevention measures are needed.

Impacts of household income and economic recession on participation in colorectal cancer screening in Korea.

To assess the impact of household income and economic recession on participation in CRC screening, we estimated annual participating proportions from 2007 to 2009 for different CRC screening modalities according to household income levels. A total of 8,042 subjects were derived from the fourth Korean National Health and Nutrition Examination Survey (KNHANES IV). Multivariate logistic regression analysis was used to estimate odds ratios and 95% confidence intervals for CRC screening with household income quartiles by gender in each year. People were less likely to attend a high-cost CRC screening such as a sigmoidoscopy or colonoscopy independent of the income quartile during the economic recession. Income disparities for participating in opportunistic cancer screening appear to have existed among both males and females during the three years (2007-2009), but were most distinctive in 2009. An increase in mortality of CRC can therefore be expected due to late detection in periods of economic crisis. Accordingly, the government should expand the coverage of CRC screening to prevent excess deaths by reducing related direct and indirect costs during the economic recession.

The effect of socioeconomic position on bone health among Koreans by gender and menopausal status.

While studies suggest that socioeconomic position (SEP) influences bone health and risk of osteoporotic fracture in postmenopausal women, few studies have simultaneously examined gender and menopause differences as they relate to SEP and bone health. Here, we investigated the relationship between SEP and bone mineral density (BMD) among Korean men, premenopausal women, and postmenopausal women using the BMD data set (n = 9,995) of the Korean National Health and Nutrition Examination Survey IV. The relationship between SEP and BMD was estimated using analysis of covariance (ANCOVA); adjustments were made for age and body mass index (BMI) in the multivariate models. The relationship between SEP and osteoporosis prevalence was estimated using logistic regression. Relative index of inequality (RII) in osteoporosis was estimated using log-binomial regression. ANCOVA (adjusted for age and for age plus BMI) showed a significant positive association between SEP and BMD among men and postmenopausal women. Logistic regression showed a significant negative association between SEP and osteoporosis prevalence among men and postmenopausal women but not in premenopausal women. The RII, estimated by log-binomial regression, showed the impact of SEP on osteoporosis to be significant in men and postmenopausal women (p < 0.05) but not in premenopausal women. Overall, low SEP was associated with both low BMD and high risk of osteoporosis among men and postmenopausal women. Efforts to reduce the economic burden of morbidity and mortality from osteoporosis should target men and postmenopausal women with low SEP.

Disparities of metabolic syndrome prevalence by age, gender and occupation among Korean adult workers.

Occupation can influence the prevalence of metabolic syndrome. Age and gender could interact with the association between occupation and metabolic syndrome. This study aimed to investigate the prevalence of metabolic syndrome among the Korean working population and determine whether the prevalence differed according to occupation, age and gender. We conducted a cross-sectional study in Korean adults using the Third Korean National Health and Nutrition Examination Survey (KNHANES III). The analysis included 3,288 workers over 19 yr old. The prevalence odds ratios (PORs) of metabolic syndrome among representative types of occupations were estimated after stratification for age and gender by logistic regression. Female manual workers had a higher prevalence of metabolic syndrome than female non-manual workers among those younger than age 50 (POR=1.95, 95%CI=1.12-3.40). However, female manual workers aged 50 and older had a lower prevalence of metabolic syndrome than female non-manual workers (POR=0.36, 95%CI=0.22-0.59). Manual occupations can be a risk factor for metabolic syndrome, but this correlation is limited to younger female workers. The effects of occupation on the prevalence of metabolic syndrome were different between older and younger workers, which could be due to longitudinal transition of socio-cultural structure.