Risk of cancer, cardiovascular disease, thromboembolism, and mortality in patients with rheumatoid arthritis receiving Janus kinase inhibitors: a real-world retrospective observational study using Korean health insurance data.

OBJECTIVES: This study investigated whether Janus kinase inhibitors (JAKis) raise the risk of cardiovascular disease (CVD), venous thromboembolism (VTE), and cancer in patients with rheumatoid arthritis (RA). METHODS: We conducted a real-world retrospective observational study using data obtained from the Korean National Health Insurance Service database. Two data sets were analyzed: tumor necrosis factor inhibitor (TNFi)/JAKi-naive RA patients (set 1) and all RA patients who used TNFis or JAKis (set 2). The incidence rate ratios (IRRs) and hazard ratios (HRs) for acute myocardial infarction (AMI), stroke, cardiovascular (CV)-related mortality, major adverse cardiovascular events (MACE), VTE, arterial thromboembolism (ATE), cancer, and all-cause mortality were compared between the JAKi and TNFi groups. RESULTS: Set 1 included 1,596 RA patients (JAKi group: 645; TNFi group: 951), and set 2 included 11,765 RA patients (JAKi group: 2,498; TNFi group: 9,267). No adverse events (AEs) showed significantly higher IRRs in the JAKi groups than in the TNFi groups of sets 1 and 2. The HRs for MACE in the JAKi groups of sets 1 and 2 were 0.59 (95% confidence [CI], 0.35 to 0.99) and 0.80 (95% CI, 0.67 to 0.97), respectively. The JAKi group of set 2 showed a significantly higher risk of all-cause mortality (HR, 1.71; 95% CI, 1.32 to 2.20), but the other AEs did not demonstrate increased risks in the JAKi groups. CONCLUSIONS: In this study, JAKis did not increase the risk of AMI, stroke, CV-related mortality, MACE, VTE, ATE, or cancer in Korean RA patients relative to TNFis.

Income-Related Mortality Inequalities and Its Social Factors among Middle-Aged and Older Adults at the District Level in Aging Seoul: An Ecological Study Using Administrative Big Data.

This study investigated income-related health inequality at sub-national level, focusing on mortality inequality among middle-aged and older adults (MOAs). Specifically, we examined income-related mortality inequality and its social factors among MOAs across 25 districts in Seoul using administrative big data from the National Health Insurance Service (NHIS). We obtained access to the NHIS's full-population micro-data on both incomes and demographic variables for the entire residents of Seoul. Slope Index of Inequality (SII) and Relative Index of Inequality (RII) were calculated. The effects of social attributes of districts on SIIs and RIIs were examined through ordinary least squares and spatial regressions. There were clear income-related mortality gradients. Cross-district variance of mortality rates was greater among the lowest income group. SIIs were smaller in wealthier districts. Weak spatial correlation was found in SIIs among men. Lower RIIs were linked to lower Gini coefficients of income for both genders. SIIs (men) were associated with higher proportions of special occupational pensioners and working population. Lower SIIs and RIIs (women) were associated with higher proportions of female household heads. The results suggest that increasing economic activities, targeting households with female heads, reforming public pensions, and reducing income inequality among MOAs can be good policy directions.

Disparities in the Diagnosis and Treatment of Gastric Cancer in Relation to Disabilities.

INTRODUCTION: We investigated potential disparities in the diagnosis, treatment, and survival of gastric cancer (GC) patients with and without disabilities. METHODS: We linked Korean National Disability Registry data with the Korean National Health Insurance database and Korean Central Cancer Registry data. This study included a total of 16,849 people with disabilities and 58,872 age- and sex-matched control subjects in whom GC had been diagnosed. RESULTS: When compared to GC patients without disabilities, patients with disabilities tended to be diagnosed at a later stage (localized stage 53.7% vs 59.0% or stage unknown 10.7% vs 6.9%), especially those with severe disabilities (P < 0.001). This was more evident in patients with mental impairment (localized stage 41.7% and stage unknown 15.2%). In addition, not receiving treatment was more common in patients with disabilities than those without disabilities (29.3% vs 27.2%, P < 0.001), and this disparity was more evident in those with severe disabilities (35.4%) and in those with communication (36.9%) and mental (32.3%) impairment. Patients with disabilities were at slightly higher risk of overall mortality as well as GC-specific mortality compared to people without disabilities (adjusted hazard ratio [aHR] = 1.18, 95% confidence interval: 1.14-1.21 and aHR = 1.12, 95% confidence interval: 1.09-1.16, respectively), and these disparities were more pronounced in those with severe disabilities (aHR = 1.62 and 1.51, respectively). DISCUSSION: Patients with disabilities, especially severe disabilities, were diagnosed with GC at a later stage, received less staging evaluation and treatment, and their overall survival rate was slightly worse compared to those without disabilities.

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.

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.

Geographic variation and factors associated with rates of knee arthroplasty in Korea-a population based ecological study.

BACKGROUND: The recent increase in knee arthroplasty (KA) use in Korea is among the highest in the world. The rapid increase in KA use suggests that the KA use in Korea could have been affected by medically unjustifiable factors. This study aimed to examine the geographic variation in the rate of KA and its associated factors in Korea. METHODS: We used the data from the National Health Insurance in Korea in 2013, from which a total of 67,086 claims for KA were obtained. We calculated the age-sex-standardized KA rates of the entire population and the crude rates of the age groups 0-64 and 65 and over in 251 districts. We assessed the geographic variation of the KA rates and examined the associated factors with a multivariate linear regression with the KA rate as a dependent variable. RESULTS: The overall rate of KA in Korea was 132.7 per 100,000 persons. The rates of KA showed a four-fold variation. The deprivation index score and the number of beds in the small to medium sized hospitals showed a positive association with the rates of KA while the number of orthopedic surgeons showed a negative association. CONCLUSIONS: Korea has been experiencing a rapid increase in the use of KA for the last decade or so, which was most prominent among the elderly population aged 65 and older. Our results suggest that the higher rate of KA is strongly related to a higher supply of beds and the socioeconomically deprived conditions. Considering that the decision concerning KA has room for discretion and also affects a considerable portion of health care expenditures, the use of KA should be thoroughly monitored with more emphasis on standardization in the decision making process and preventive measures that can lessen the need for KA.

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.

Trends in inequality in life expectancy at birth between 2004 and 2017 and projections for 2030 in Korea: multiyear cross-sectional differences by income from national health insurance data.

OBJECTIVES: The current status, time trends and future projections of a national health equity target are crucial elements of national health equity surveillance. This study examined time trends in inequality by income in life expectancy (LE) at birth between 2004 and 2017 and made future projections for the year 2030 in Korea. DESIGN: Using individually linked mortality data, time trends in inequality by income in LE at birth were examined. The LE projection was made with the Lee-Carter model. SETTING: Total Korean population and death data derived from the National Health Information Database of the National Health Insurance Service. PARTICIPANTS: A total of 685 773 157 subjects and 3 486 893 deaths between 2004 and 2017 were analysed. PRIMARY AND SECONDARY OUTCOME MEASURES: Annual LE and the magnitude of inequality by income in LE between 2004 and 2030. RESULTS: Inequality by income in LE among the total Korean population increased during the past 14 years, and this inequality is projected to become even greater in the future. In 2030, the magnitude of inequality by income in LE is projected to increase by 0.25 years in comparison to the magnitude in 2017. The increase in LE inequality was projected to be more prominent among women, with a projected 1.08 year increase in LE inequality between 2017 and 2030. CONCLUSION: Aggressive policies should be developed to close the increasing LE gap in Korea. LE inequalities by income should be considered as a measurable target for health equity in the process of establishing the National Health Plan 2030 in Korea.

An ecological study of geographic variation and factors associated with cesarean section rates in South Korea.

BACKGROUND: Korea is in a condition where the impact of patient and supplier factors on cesarean section rates can be clearly described. The cesarean section rates in Korea are among the highest in the world while the number of obstetricians is decreasing sharply. This study aimed to investigate the geographic variation in cesarean section rates in Korea and its factors. METHODS: The data were obtained from the National Health Insurance database in Korea in 2013. We calculated the age-standardized and crude cesarean section rates of 251 districts in Korea and variation statistics. A linear regression analysis was performed to determine factors for cesarean section rates. RESULTS: The overall cesarean section rate in Korea was 364.6 cases per 1000 live births. The deprivation index score was strongly associated with the increase in the cesarean section rate while the density of hospital obstetricians and hospital beds showed a negative association. Average maternal age and total fertility rate showed a negative relationship with the cesarean section rate. CONCLUSIONS: Korea is suffering from a continuing decrease in obstetricians. Our study shows that this decline has more of an effect on mothers in the disadvantaged areas. Securing equal access to obstetric care among areas is necessary, and measures to encourage obstetricians and mothers not to opt for cesarean section are required.

Hospitalizations for ambulatory care sensitive conditions as an indicator of access to primary care and excess of bed supply.

BACKGROUND: Ambulatory care sensitive conditions (ACSC) hospitalization is a widely accepted measure of the access to primary care. However, given its discretionary characteristics, the ACSC hospitalization can be a measure reflecting the influence of hospital bed supply. In Korea, where the quality of primary care and oversupply of hospital beds are coexistent concerns, ACSC hospitalization can be used to examine the impact of both factors. This study was performed to investigate the ACSC hospitalization rate as a measure of the hospital bed supply as well as access to primary care. METHODS: Data were obtained from the National Health Insurance Database for 2015. We calculated the age-sex standardized hospitalization rates for ACSC in the total population and crude rates of ACSC hospitalization for three different age groups in 252 districts in Korea. We calculated the variation statistics of ACSC hospitalization rates, and we estimated a linear regression model to investigate the factors for ACSC hospitalization. RESULTS: There was a very high geographic variation in ACSC hospitalization rates. Higher density of primary care physicians was associated with a decreased ACSC hospitalization rate while a higher density of hospital beds in small to medium sized hospitals was associated with an increased rate. The deprivation index score had a strongly positive association with the ACSC hospitalization rates. CONCLUSION: ACSC hospitalization, while being a negative index of primary care access, can also be a measure indicating the impact of the hospital bed supply, and it is still a valid measure of the disparity of health care, the original motivation for this topic.

Combined effects of four major geriatric syndromes on adverse outcomes based on Korean National Health Insurance claims data.

AIM: Geriatric syndromes are common among older individuals, and can affect their health and quality of life. The present study aimed to determine if combinations of geriatric syndromes affected adverse outcomes among older Koreans. METHODS: Korean national health insurance data were collected for a cohort of 5 058 720 individuals who were aged ≥65 years in 2008. The same data source was used to follow these individuals until 2015. Diagnostic codes were used to assess four major geriatric syndromes (delirium, fall-related fractures, incontinence and pressure ulcers) and adverse outcomes (mortality and nursing home institutionalization). RESULTS: The prevalence of geriatric syndromes was 0.3% for delirium, 3.49% for fall-related fractures, 1.08% for incontinence and 0.82% for pressure ulcers. All four geriatric syndromes were associated with increased risks of institutionalization (adjusted hazard ratio [aHR] 2.18, 95% CI 2.08-2.17 for delirium; aHR 1.59, 95% CI 1.58-1.60 for fall-related fractures; aHR 1.43, 95% CI 1.41-1.44 for incontinence; and aHR 2.51, 95% CI 2.47-2.55 for pressure ulcers) and increased risks of mortality (aHR 2.13, 95% CI 2.08-2.17 for delirium; aHR 1.41, 95% CI 1.40-1.42 for fall-related fractures; aHR 1.09, 95% CI 1.07-1.10 for incontinence; and aHR 3.23, 95% CI 3.20-3.27 for pressure ulcers). The aHR for institutionalization were 1.64 (95% CI 1.63-1.65) for one geriatric syndrome, 2.40 (95% CI 2.35-2.44) for two coexisting geriatric syndromes and 2.56 (95% CI 2.35-2.74) for three coexisting geriatric syndromes. The aHR for mortality were 1.52 (95% CI 1.51-1.53) for one geriatric syndrome, 2.36 (95% CI 2.32-2.40) for two coexisting geriatric syndromes and 2.90 (95% CI 2.72-3.09) for three coexisting geriatric syndromes. CONCLUSIONS: Delirium, fall-related fractures, incontinence and pressure ulcers were associated with increased risks of institutionalization and mortality. The magnitude of these risks increased with increasing numbers of coexisting geriatric syndromes. Geriatr Gerontol Int 2018; 18: 1463-1468.

Comparison of District-level Smoking Prevalence and Their Income Gaps from Two National Databases: the National Health Screening Database and the Community Health Survey in Korea, 2009-2014.

BACKGROUND: We compared age-standardized prevalence of cigarette smoking and their income gaps at the district-level in Korea using the National Health Screening Database (NHSD) and the Community Health Survey (CHS). METHODS: Between 2009 and 2014, 39,049,485 subjects participating in the NHSD and 989,292 participants in the CHS were analyzed. The age-standardized prevalence of smoking and their interquintile income differences were calculated for 245 districts of Korea. We examined between-period correlations for the age-standardized smoking prevalence at the district-level and investigated the district-level differences in smoking prevalence and income gaps between the two databases. RESULTS: The between-period correlation coefficients of smoking prevalence for both genders were 0.92-0.97 in NHSD and 0.58-0.69 in CHS, respectively. When using NHSD, we found significant income gaps in all districts for men and 244 districts for women. However, when CHS was analyzed, only 167 and 173 districts for men and women, respectively, showed significant income gaps. While correlation coefficients of district-level smoking prevalence from two databases were 0.87 for men and 0.85 for women, a relatively weak correlation between income gaps from the two databases was found. CONCLUSION: Based on two databases, income gaps in smoking prevalence were evident for nearly all districts of Korea. Because of the large sample size for each district, NHSD may provide stable district-level smoking prevalence and its income gap and thus should be considered as a valuable data source for monitoring district-level smoking prevalence and its socioeconomic inequality.

Geographic Variation in Morbidity and Mortality of Cerebrovascular Diseases in Korea during 2011-2015.

BACKGROUND: Little is known about within-country variation in morbidity and mortality of cerebrovascular diseases (CVDs). Geographic differences in CVD morbidity and mortality have yet to be properly examined. This study examined geographic variation in morbidity and mortality of CVD, neighborhood factors for CVD morbidity and mortality, and the association between CVD morbidity and mortality across the 245 local districts in Korea during 2011-2015. METHODS: District-level health care utilization and mortality data were obtained to estimate age-standardized CVD morbidity and mortality. The bivariate Pearson correlation was used to examine the linear relationship between district-level CVD morbidity and mortality Z-scores. Simple linear regression and multivariate analyses were conducted to investigate the associations of area characteristics with CVD morbidity, mortality, and discrepancies between morbidity and mortality. RESULTS: Substantial variation was found in CVD morbidity and mortality across the country, with 1074.9 excess CVD inpatients and 73.8 excess CVD deaths per 100,000 between the districts with the lowest and highest CVD morbidity and mortality, respectively. Higher rates of CVD admissions and deaths were clustered in the noncapital regions. A moderate geographic correlation between CVD morbidity and mortality was found (Pearson correlation coefficient = .62 for both genders). Neighborhood level indicators for socioeconomic disadvantages, undersupply of health care resources, and unhealthy behaviors were positively associated with CVD morbidity and mortality and the relative standing of CVD mortality vis-à-vis morbidity. CONCLUSIONS: Policy actions targeting life-course socioeconomic conditions, equitable distribution of health care resources, and behavioral risk factors may help reduce geographic differences in CVD morbidity and mortality in Korea.

Level of Agreement and Factors Associated With Discrepancies Between Nationwide Medical History Questionnaires and Hospital Claims Data.

OBJECTIVES: The objectives of this study were to investigate the agreement between medical history questionnaire data and claims data and to identify the factors that were associated with discrepancies between these data types. METHODS: Data from self-reported questionnaires that assessed an individual's history of hypertension, diabetes mellitus, dyslipidemia, stroke, heart disease, and pulmonary tuberculosis were collected from a general health screening database for 2014. Data for these diseases were collected from a healthcare utilization claims database between 2009 and 2014. Overall agreement, sensitivity, specificity, and kappa values were calculated. Multiple logistic regression analysis was performed to identify factors associated with discrepancies and was adjusted for age, gender, insurance type, insurance contribution, residential area, and comorbidities. RESULTS: Agreement was highest between questionnaire data and claims data based on primary codes up to 1 year before the completion of self-reported questionnaires and was lowest for claims data based on primary and secondary codes up to 5 years before the completion of self-reported questionnaires. When comparing data based on primary codes up to 1 year before the completion of self-reported questionnaires, the overall agreement, sensitivity, specificity, and kappa values ranged from 93.2 to 98.8%, 26.2 to 84.3%, 95.7 to 99.6%, and 0.09 to 0.78, respectively. Agreement was excellent for hypertension and diabetes, fair to good for stroke and heart disease, and poor for pulmonary tuberculosis and dyslipidemia. Women, younger individuals, and employed individuals were most likely to under-report disease. CONCLUSIONS: Detailed patient characteristics that had an impact on information bias were identified through the differing levels of agreement.

Using the National Health Information Database of the National Health Insurance Service in Korea for Monitoring Mortality and Life Expectancy at National and Local Levels.

This study explores whether the National Health Information Database (NHID) can be used to monitor health status of entire population in Korea. We calculated the crude mortality rate and life expectancy (LE) at birth across the national, provincial, and municipal levels using the NHID eligibility database from 2004 to 2015, and compared the results with the corresponding values obtained from the Korean Statistical Information Service (KOSIS) of Statistics Korea. The study results showed that the ratio of crude mortality rate between the two data was 0.99. The absolute difference between the LE of the two data was not more than 0.5 years, and did not exceed 0.3 years in gender specific results. The concordance correlation coefficients (CCC) between the crude mortality rates from NHID and the rates from KOSIS ranged 0.997-0.999 among the municipalities. For LE, the CCC between the NHID and KOSIS across the municipalities were 0.990 in 2004-2009 and 0.985 in 2010-2015 among men, and 0.952 in 2004-2009 and 0.914 in 2010-2015 among women, respectively. Overall, the NHID was a good source for monitoring mortality and LE across national, provincial, and municipal levels with the population representativeness of entire Korean population. The results of this study indicate that NHID may well contribute to the national health promotion policy as a part of the health and health equity monitoring system.

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 Effect of Geographic Units of Analysis on Measuring Geographic Variation in Medical Services Utilization.

OBJECTIVES: We aimed to evaluate the effect of geographic units of analysis on measuring geographic variation in medical services utilization. For this purpose, we compared geographic variations in the rates of eight major procedures in administrative units (districts) and new areal units organized based on the actual health care use of the population in Korea. METHODS: To compare geographic variation in geographic units of analysis, we calculated the age-sex standardized rates of eight major procedures (coronary artery bypass graft surgery, percutaneous transluminal coronary angioplasty, surgery after hip fracture, knee-replacement surgery, caesarean section, hysterectomy, computed tomography scan, and magnetic resonance imaging scan) from the National Health Insurance database in Korea for the 2013 period. Using the coefficient of variation, the extremal quotient, and the systematic component of variation, we measured geographic variation for these eight procedures in districts and new areal units. RESULTS: Compared with districts, new areal units showed a reduction in geographic variation. Extremal quotients and inter-decile ratios for the eight procedures were lower in new areal units. While the coefficient of variation was lower for most procedures in new areal units, the pattern of change of the systematic component of variation between districts and new areal units differed among procedures. CONCLUSIONS: Geographic variation in medical service utilization could vary according to the geographic unit of analysis. To determine how geographic characteristics such as population size and number of geographic units affect geographic variation, further studies are needed.

Trends of antidiabetic drug use in adult type 2 diabetes in Korea in 2002-2013: Nationwide population-based cohort study.

This study investigated trends in the prescription of antidiabetic medications for patients with type 2 diabetes, focusing on changing patterns of prescriptions and the cost of drugs during the last 10 years. Retrospective data on patients with type 2 diabetes aged 30 years or older were analyzed using information from the National Health Information Database collected by the National Health Insurance Service in Korea from January 2002 to December 2013. We identified patients with type 2 diabetes who had at least one service claim in each year during the study period. The prescribing information was collected and fixed-dose combination tablets were counted as each of their constituent classes. The total number of adults with type 2 diabetes who were treated using antidiabetic agents increased from 0.87 million in 2002 to 2.72 million in 2013 in Korea. Among antidiabetic medications in 2002, sulfonylurea (SU) was the most commonly used agent (87.2%), and metformin was the second (52.9%). However, in 2013, the use of metformin increased to 80.4% of the total antidiabetic prescriptions. The use of dipeptidyl peptidase-4 (DPP-4) inhibitor increased remarkably after release in late 2008 and composed one-third of the market share with 1 million prescriptions (38.4%) in 2013. Among the prescriptions for monotherapy, only 13.0% were metformin in 2002, but the amount increased to 53.2% by 2013. In contrast, the use of SU declined dramatically from 75.2% in 2002 to 30.6% in 2013. Dual and triple combinations steadily increased from 35.0% and 6.6% in 2002 to 44.9% and 15.5% in 2013, respectively. In 2013, SU with metformin (41.7%) and metformin with DPP-4 inhibitor (32.5%) combination were most frequently prescribed. The total antidiabetic medication cost increased explosively from U.S. $70 million (82.5 billion won) in 2002 to U.S. $4 billion (480 billion won) in 2013.The use of antidiabetic agents and their costs have been increasing steadily. Metformin is the most commonly used drug recently. The use of DPP-4 inhibitor increased significantly over the past decade, whereas the use of SU decreased. However, SUs still remain the most commonly prescribed second-line agents with metformin in 2013.

The relationship between the social network of community-living elders and their health-related quality of life in Korean province.

OBJECTIVES: This study aimed to collect information that will help enhance the social networks and improve the quality of life among elderly people by observing the relationship between their social network and health-related quality of life (HRQoL) and by analyzing social network factors affecting HRQoL. METHODS: This study was based on the 2008 Community Health Survey in Yeoncheon County. Three hundred elders were included in the study population. We compared the revised Lubben Social Network Scale (LSNS-R) score and Euro quality of life-5 dimensions health status index by demographic characteristics and chronic disease prevalence. We analyzed the data using multiple regression and tobit regression by setting the HRQoL as the dependent variable and social network and other characteristics as the independent variables. We analyzed social network factors by using factor analysis. RESULTS: The LSNS-R score differed significantly according to age and existence of a spouse. According to the results from the hierarchical multiple regression analysis, the LSNS-R explained 0.10 of the variance and LSNS-R friends factor explained 0.10 of the variance. The tobit regression indicated that the contribution of the LSNS-R family size factor to the regression coefficient of the independent variable that affected the HRQoL was B(T)=2.96, that of the LSNS-R family frequency factor was B(T)=3.60, and that of LSNS-R friends factor was B(T)=5.41. CONCLUSIONS: Social networks among elderly people had a significant effect on HRQoL and their networks of friends had a relatively higher effect than those of family members.