Search

Background Opportunities for paid employment provide meaningful ways for those with disabilities to participate in society and achieve financial independence. Although the onset age of disabilities can alter individuals’ attitudes toward accepting their disabilities and their desire for work, the lack of data limits relevant empirical research. The purpose of this study is to examine the effect of the onset age on employment, job security (permanent vs. temporary), and wage level among visually impaired adults in South Korea. Methods We used three years of the National Survey on Persons with Disabilities data, 2011, 2014, and 2017, and included 583 participants in this study. We used a logistic regression model for the employment status and a multinomial logistic regression model for job security. We analyzed log monthly wage by a multivariate linear regression model, which subdivided the age groups, with 20–49 years old denoting prime-aged (n = 245) and 50–64 years old denoting late-middle-aged (n = 338). For each age group, we conducted a sub-analysis by sex. Results For prime-aged adults, the employment probability decreased as the age of visual impartment onset increased, and women in particular experienced a lower employment rate for both permanent and temporary jobs when their disability onset age was above 25. However, among permanent employees, monthly wages were higher if the onset age was 25 + compared to when the onset age was 0–5 years old. In late middle-aged adults, adult onset disabilities were associated with higher odds of employment and higher wages for temporary jobs, implying these individuals worked unskilled or manual jobs. Conclusions In prime-aged adults, higher monthly wages among permanent employees showed that they were more likely to continue their original work, whereas in late-middle-aged adults, adult-onset disabilities were associated with a higher employment rate and higher wages for temporary jobs, suggesting the need for further investigation into job quality. These findings indicate a need for differentiated policy approaches considering the onset age of visual impairment to improve labor market outcomes throughout individuals’ lifespans.

The National Health Insurance Service in South Korea has conducted a telephone outreach program to improve medication adherence for hypertension and diabetes patients since 2014.To evaluate the direct outcomes of the program.Patients were identified among those who visited an outpatient clinic at least twice or used an inpatient service at least once for hypertension or diabetes during 6-month intervals and who were nonadherent based on the proportion of days covered (PDC) calculated. As a preliminary intervention, participants were mailed an information leaflet on their own medication adherence and other tips for effective self-management of chronic diseases. For the intervention, two phone calls and three phone messages were made to patients by 24 participating regional offices. Ultimately, 2,428 hypertension patients and 884 diabetes patients received the intervention. Propensity matching was used based on age, sex, and the Charlson Comorbidity Index to select 12,140 hypertension and 4,420 diabetes patients as controls in the non-participating regions. The outcome was PDC. Multivariate ordinary least squares or logistic regression analysis were used with difference-in-difference specification.The adjusted quarterly PDC increased by 1.96%p for hypertension (p = 0.023) and by 7.79%p for diabetes patients (p 0.001). Approximately 40.6% and 51.7% of hypertension and diabetes patients in the treatment arm (p = 0.0069) became adherent after the intervention, whereas the corresponding proportions were 37.7% and 41.4% (p 0.001) in the control group. Both treatment groups showed a higher likelihood of good medication adherence (hypertension: odds ratio = 1.157, 95% CI [1.058, 1.265]; diabetes: odds ratio = 1.532, 95% CI [1.323, 1.774]). The control group, who received only a print intervention with a mailed leaflet, also showed a dramatic increase in medication adherence.An insurer-coordinated telephone-administered program resulted in improvement of medication adherence among patients with hypertension and diabetes.

Background Although severe dementia could protect against suicide death by decreasing a person’s capacity to implement a suicide plan, patients with early dementia may have better cognition, giving them more sustained insight into their disease and better enabling them to carry out a suicide plan. This study investigated suicide risk in older adults within 1 year of receiving a diagnosis of dementia. Methods This study used National Health Insurance Service Senior Cohort data and included 36 541 older adults with newly diagnosed dementia (a Mini-Mental State Examination score ≤ 26 and a Clinical Dementia Rating score ≥ 1 or a Global Deterioration Scale score ≥ 3), including Alzheimer disease, vascular dementia and other/unspecified dementia, from 2004 to 2012. We selected older adults without dementia through 1:1 propensity-score matching using sex, age, comorbidities and index year, with follow-up throughout 2013. We estimated adjusted hazard ratios (AHRs) of suicide deaths within 1 year after diagnosis using a time-dependent Cox proportional hazards model. Results We verified 46 suicide deaths during the first year after a dementia diagnosis. Older adults with dementia had an increased risk of suicide death compared to those without dementia (AHR 2.57; 95% confidence interval [CI] 1.49–4.44). Older adults with Alzheimer disease (AHR 2.50; 95% CI 1.41–4.44) or other/unspecified dementia (AHR 4.32; 95% CI 2.04–9.15) had an increased risk of suicide death compared to those without dementia. Patients with dementia but without other mental disorders (AHR 1.96; 95% CI 1.02–3.77) and patients with dementia and other mental disorders (AHR 3.22; 95% CI 1.78–5.83) had an increased risk of suicide death compared to patients without dementia. Patients with dementia and schizophrenia (AHR 8.73; 95% CI 2.57–29.71), mood disorders (AHR 2.84; 95% CI 1.23–6.53) or anxiety or somatoform disorders (AHR 3.53; 95% CI 1.73–7.21), respectively, had an increased risk of suicide death compared to patients with those conditions but without dementia. Limitations This study examined only elderly patients in South Korea, a population with a substantially higher suicide rate than the global population. Caution must be exercised when generalizing the results to populations with dissimilar backgrounds. Conclusion Patients with dementia had an increased risk of suicide death within 1 year after diagnosis compared to those without dementia.

Background: The introduction of new vaccines has been delayed in some countries in the Asia-Pacific region, which has led to delays in accessing vaccines for target patients. However, the approval lag of vaccines in the Asia-Pacific region has not been assessed. The objective of this study is to assess the availability and approval lag of vaccines in Asia-Pacific countries and compare them among Asia-Pacific countries, the United States (US), and Europe (EU). Methods: The information on vaccines prequalified by the World Health Organization (WHO) between 2010 and 2019 was obtained primarily from the WHO website. The date of approval of the WHO prequalified vaccine in Australia, India, South Korea, Thailand, Singapore, Malaysia, the US, and EU was retrieved from the official website of national regulatory agencies. The vaccines were divided into two groups based on their first approval pathway, that is, vaccines that were first approved by SRA (Stringent Regulatory Authority including the US, EU, and WHO) and those that were first approved by non-SRA. The absolute approval lag represented the availability of the vaccine. Relative approval lag represented the lag time between the approval date of the country of interest and the first global approval date and was measured as the median approval lag. A Mann–Whitney U test was used to examine statistical differences between relative approval lag between the SRA first and the non-SRA first groups. Results: A total of 92 vaccines were prequalified by the WHO between 2010 and 2019, but only 61 vaccines were included in the analysis. Over 50% of vaccines were first licensed by non-SRAs. Of all the WHO-prequalified vaccines, the median approval lag in the ASEAN countries in this study was longer than those in the US and EU, with a median of 30 months in Australia, 15 months in South Korea, 52 months in Thailand, and 23 months in Singapore, compared to 0 months in the US and EU. The differences in approval lags between SRA first vaccines and non-SRA first vaccines were statistically significant in South Korea and Thailand (p < 0.05). Conclusions: The approval lag of vaccines was observed in the Asia-Pacific region, indicating a gap between the Asia-pacific region and the US and EU in regard to access to new vaccines. Future studies need to analyze the background factors related to the gap in availability and vaccine approval lag in the Asia-Pacific region and assess the impact of vaccine approval lag in the region.

Background We evaluated the effect of statin use on new-onset type 2 diabetes among individuals without atherosclerotic cardiovascular disease (ASCVD) using nationally representative South Korean claims data (2002–2013, N = 1,016,820). Methods A total of 13,698 patients (statin users 5273, non-statin users 5273) aged 40–74 years, newly diagnosed with dyslipidemia but without any history of diabetes or ASCVD, were selected in 2005. We followed up the final sample until 2013 and evaluated the cumulative incidence of type 2 diabetes. We used extended Cox regression models to estimate the time-varying adjusted hazard ratios of statin use on new-onset type 2 diabetes. We performed further analyses based on the cumulative defined daily dose of statin received per year to evaluate the degree of risk compared to non-statin users. Results Over the mean follow-up period of 7.1 years, 3034 patients developed type 2 diabetes; the number of statin users exceeded that of non-users, demonstrating that statin use significantly increased the risk of new-onset type 2 diabetes. The risk of new-onset type 2 diabetes differed among statin users according to cDDD per year (adjusted HR = 1.31 [95% CI 1.18–1.46] for less than 30 cDDD per year; 1.58 [1.43–1.75] for 30–120 cDDD per year; 1.83 [1.62–2.08] for 120–180 cDDD per year; and 2.83 [2.51–3.19] for more than 180 cDDD per year). The diabetogenic effect of pitavastatin was not statistically significant, but the risk was the largest for atorvastatin. Long-term exposure (≥ 5 years) to statins was associated with a statistically significant increase in the risk of new onset type 2 diabetes in all statin subtypes explored, with the highest magnitude for simvastatin (HR = 1.916, 95% CI 1.647–2.228) followed by atorvastatin (HR = 1.830, 95% CI 1.487–2.252). Conclusions Statin use was significantly associated with an increased risk of new-onset type 2 diabetes. We also found a dose–response relationship in terms of statin use duration and dose maintenance. Periodic screening and monitoring for incident type 2 diabetes may be warranted in long-term statin users.

Single-tablet regimens (STRs) should be considered for patients with HIV/AIDS to increase medication compliance and improve clinical outcomes. This study compared variations in the prescription trends between STRs and multiple-tablet regimens (MTRs) for treatment-naïve patients with HIV/AIDS after the approval of the new STRs, a proxy indicator for improvement in medication adherence. The medical and pharmacy claim data were retrospectively obtained from the Health Insurance Review and Assessment service, which contains basic information on the patients’ sociodemographic characteristics and treatment information for the entire Korean population. From 2013 to 2018, a total of 6737 patients with HIV/AIDS were included. Most patients were men (92.8%, n = 6251) and insured through the National Health Insurance (95.1%, n = 6410). The mean number of pills in their antiretroviral treatment regimens decreased from 2.8 ± 1.2 in 2013 to 1.2 ± 1.0 in 2018. After the first STR (EVG/c/TDF/FTC) was approved in 2014, prescription transitions from MTR to STR were observed among more than 38% of patients. In 2018, most treatment-naïve patients were prescribed STRs (91.2%). There was a time lag for STR prescription trends in non-metropolitan hospitals compared with those in metropolitan cities. Our data provide a valuable perspective for evaluating ART regimen prescription patterns on a national scale.

Objectives The present study evaluated suicide risk within 1 year after discharge among older adults with stroke as a function of depression onset. Method We used the Korean National Health Insurance Service-Senior cohort data and included first discharged patients with a stroke as the principal diagnosis. The comparison group was selected by a 1:2 case-control propensity score matching for age, sex, Charlson comorbidity index, and diagnosis year between 2005 and 2012. Suicide deaths were measured by code for causes of death from Statistics Korea, and the main outcome was suicide death within 1 year following discharge. An adjusted hazard ratio (AHR) of suicidal risk was measured using a Cox proportional hazard model. Results In the total sample of 128 286 older adults (aged 63-114 years), the higher suicidal risk was examined for stroke patients vs the comparison group (AHR = 1.4; 95% confidence interval [CI], 1.1-1.8). Stroke patients with depression had an increased suicide risk (AHR = 2.9; 95% CI, 1.8-4.8) but only for poststroke depression (AHR = 4.1; 95% CI, 1.8-9.5). Pre and poststroke depression suicidality (AHR = 4.8; 95% CI, 2.1-11.1) was also higher when compared to stroke patients without depression. Conclusions Poststroke patients are at increased suicidal risk during 1 year following discharge. Furthermore, patients who were diagnosed with depression after a stroke are more likely to commit suicide than stroke patients without depression. This suggests a necessity for early suicide preventive intervention for stroke patients while considering depressive symptomology.

Inappropriate antibiotic use is a main driver in microbes' development of antibiotic resistance. This study explored the extent to which patient, provider, and other factors contribute to antibiotic prescriptions for acute upper respiratory tract infection. We exploited exogenous patients' temporary and permanent migration from their residential area to robustly separate patient-related, provider-related, and other factors in terms of their contributions to antibiotic use. We analyzed claims of 914,013 URI patients from the 2002-2019 Korean National Health Insurance Sample Cohort Database. The results showed that both patient- and provider-related factors affect antibiotic use for upper respiratory tract infection treatment, although providers' impact is stronger than that of patients. Further decomposition analysis confirmed that provider-related factors explain about 55% of the total variance in antibiotic use. The demand side contributes to approximately 33-34% of the variance. Providers' local market share and market competitiveness are associated with antibiotic prescription. The findings suggest that regulations to reduce antibiotic consumption in Korea should target both patients and providers with appropriate quantifiable penalties.

Background Evidence regarding the risk of coronavirus disease (COVID-19) and the major adverse clinical outcomes of COVID-19 among people with disabilities (PwDs) is scarce. Objective This study investigated the association of disability status with the risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) test positivity and the risk of major adverse clinical outcomes among participants who tested positive for SARS-CoV-2. Methods This study included all patients (n = 8070) who tested positive for SARS-CoV-2 and individuals without COVID-19 (n = 121,050) in South Korea from January 1 to May 30, 2020. The study variables included officially registered disability status from the government, SARS-CoV-2 test positivity, and major adverse clinical outcomes of COVID-19 (admission to the intensive care unit, invasive ventilation, or death). Results The study participants included 129,120 individuals (including 7261 PwDs), of whom 8070 (6.3%) tested positive for SARS-CoV-2. After adjusting for potential confounding factors, PwDs had an increased risk of SARS-CoV-2 test positivity compared with people without disabilities (odds ratio [OR]: 1.36, 95% confidence interval [CI]: 1.24–1.48). Among participants who tested positive for SARS-CoV-2, PwDs were associated with an increased risk of major adverse clinical outcomes from COVID-19 compared to those without disabilities (OR: 1.43, 95% CI: 1.11–1.86). Conclusions PwDs had an increased risk of COVID-19 and major adverse clinical outcomes of COVID-19 compared with people without disabilities. Given the higher vulnerability of PwDs to COVID-19, tailored policy and management to protect against the risk of COVID-19 are required.

Objectives We aimed to identify the impact of poverty on suicide risk in older adults. Method The data used in this study was obtained from the National Health Insurance Service-Senior claims database from 2002 to 2013. A total of 558 147 individuals were followed for up to 12 years. Poverty was assessed from insurance premium levels, and causes of death were analysed by linking individuals' deaths to the data for causes of death from the National Statistics Office in South Korea. Cox proportional hazard models were used to analyse the associations between poverty and suicide deaths after adjustments for possible confounders. Results Among 558 147 older adults (aged 60-119 years), the poverty group had an increased risk of suicide compared with the high-income group (adjusted hazard ratio [AHR], 1.34; 95% confidence interval [CI], 1.22-1.47), and poverty-group males had a significantly higher risk of suicide than males in the high-income group (AHR, 1.50; 95% CI, 1.33-1.68). Adults aged 60 to 74 years in the poverty group had a higher risk of suicide than those with a high income in the same age group (AHR, 1.41; 95% CI, 1.27-1.57). However, no statistically significant income gradient was found for females or adults aged 75 years or older. Conclusions Our findings revealed that poverty is a risk factor for death by suicide in older adults. Suicide prevention strategies for older adults should be specifically tailored by income level.

Background Patients with psychiatric disorders are considered to be at increased suicide risk following discharge. We aimed to identify suicide risk during one year after discharge among adults with psychiatric disorders compared to those without psychiatric disorders. Method This study used a nationally representative cohort including patients discharged with an initial primary diagnosis of a psychiatric disorder and control subjects selected by 1:3 case-control propensity matching between 2005 and 2012. The dependent variable was death by suicide during one year after discharge. Adjusted hazard ratios (AHR) of suicide risk were estimated by the Cox proportional hazard model. Results In a cohort of 50,868 adults, the suicide rate was higher for patients with a psychiatric disorder compared to non-psychiatric patients (AHR 7.2, 95% confidence interval [CI] 4.9–10.6), especially in young adults (AHR 18.6, 95%CI 6.4–54.1), and patients with multiple psychiatric disorders (AHR 12.5, 95%CI 7.9–20.0). Among psychiatric disorder categories, the suicide rate was highest for depressive disorder, followed by bipolar disorder, substance use disorder, schizophrenia. Patients with psychiatric disorders who received outpatient care during one year after discharge were at lower risk of suicide than those who did not receive or otherwise received fewer outpatient treatments. Limitations Data were not available on risk factors such as suicide attempts. The suicide risk for shorter periods could not be determined due to the limited data. Conclusions Patients with psychiatric disorders are at high suicide risk during one year after hospital discharge. Outpatient follow-up is an effective prevention strategy.

Background Studies on healthcare service use among persons with visual impairments in countries with different healthcare systems are needed for drawing global inferences. Objective The goal was to assess the impact of visual impairment on healthcare service use. Methods A retrospective cohort study on health insurance claims data from the National Health Insurance System (NHIS) was conducted. All data from 2002 to 2013 for 2206 and 8824 persons with and without visual impairments, respectively, were extracted and aggregated monthly, generating a total of 162,876 and 568,459 person-month observations, respectively. The dependent variable was total expenditures. Difference-in-difference estimations based on a multivariate log-normal random-effect regression were employed. Results Persons with visual impairments spent 5.7% and 6.8% more on total healthcare expenditures per month and outpatient healthcare expenditures, respectively, than those without visual impairments, after adjusting for pre-impairment differences. Further results revealed an upward trend in expenditures, particularly among those with visual impairments; this increase was the highest during the year prior impairment (approximately 32% and 21% more for total and outpatient services, respectively, compared with baseline). Inpatient healthcare expenditures showed a similar increase (by approximately 26%) during the year prior impairment compared with baseline; however, the magnitude dropped to approximately 14% and 6% during the 1st and 2nd years of impairment, respectively. Conversely, the annual pattern of expenditure increase was parallel over time for persons without visual impairments, regardless of service. Conclusion Our findings suggest a need for health management and effective care use, particularly the year prior to visual impairment onset.

ObjectiveThe aim of the present study was to compare selected obesity indicators with comprehensive health status.DesignThe study employed a pooled cross-sectional design.SettingBMI, waist circumference, waist-to-height ratio (WHtR) and body fat percentage were considered as indirect obesity indicators. The Edmonton Obesity Staging System (EOSS) was used as a composite indicator to comprehensively reflect obesity-related co-morbidities. Cohen’sκcoefficient was used to evaluate inter-measurement agreement for obesity. Conformity of indirect obesity indicators to the EOSS was assessed based on percentage agreement (proportion classified as obese and severely unhealthy as a result of obesity among the total sample), sensitivity (proportion classified as obese among individuals severely unhealthy as a result of obesity) and specificity (proportion classified as non-obese among fairly healthy individuals). Logistic regression analysis was used to identify the sociodemographic factors most strongly associated with conformity.ParticipantsThe study included 17338 adults from the Korea National Health and Nutrition Examination survey conducted between July 2008 and May 2011.ResultsLevel of conformity to the EOSS was highest for WHtR (60·77 %) and lowest for BMI (35·96 %). WHtR and BMI had the highest sensitivity (53·7 %) and specificity (98·4 %), respectively. Predictability of conformity was lower among men for all indirect obesity indicators.ConclusionsWHtR has the greatest potential to identify individuals at risk of health problems due to obesity. Individual demographic factors must be considered in selecting the most appropriate obesity measurement.

Objectives This study analyzed the relative time trends of prices of healthy versus unhealthy foods in South Korea for the 20 years from 1995 to 2015. Study design Time series analysis was used. Methods We analyzed price trends of selected food items in the food groups of grains, vegetables, meats, sweets, spices, fast foods, and non-alcoholic beverages. We obtained nominal prices from the monthly reports of the 2006 Consumer Price Survey for representative items in each food group. Results The real price of processed meat increased by 1.2 percentage points less than the overall Consumer Price Index (CPI) increase, whereas beef prices increased by 2.4 percentage points more than the CPI increase. The price of soda was cheaper than that of other non-alcoholic beverages, whereas the real prices of milk showed statistically significantly larger yearly increases (by 1.4 percentage points, respectively) than that of the CPI. The yearly increases in the real prices of pizza, hamburgers, and fried chicken—three representative fast-food items that were mostly consumed by eating out or through home delivery—were statistically significantly less than those of the CPI (by 1.5, 1.4, and 0.3 percentage points, respectively). Conclusions Our results show that relatively healthy foods showed higher real price increases than the CPI increase, whereas the opposite occurred for unhealthy foods.

Influenza is an important public health concern. We propose a new real-time influenza-like illness (ILI) surveillance system that utilizes a nationwide prospective drug utilization monitoring in Korea. We defined ILI-related claims as outpatient claims that contain both antipyretic and antitussive agents and calculated the weekly rate of ILI-related claims, which was compared to weekly ILI rates from clinical sentinel surveillance data during 2014–2018. We performed a cross-correlation analysis using Pearson’s correlation, time-series analysis to explore actual correlations after removing any dubious correlations due to underlying non-stationarity in both data sets. We used the moving epidemic method (MEM) to estimate an absolute threshold to designate potential influenza epidemics for the weeks with incidence rates above the threshold. We observed a strong correlation between the two surveillance systems each season. The absolute thresholds for the 4-years were 84.64 and 86.19 cases per 1000claims for claims data and 12.27 and 16.82 per 1000 patients for sentinel data. The epidemic patterns were more similar in the 2016–2017 and 2017–2018 seasons than the 2014–2015 and 2015–2016 seasons. ILI claims data can be loaded to a drug utilization review system in Korea to make an influenza surveillance system.

Background: The high prevalence of chronic diseases has been an ongoing public concern. The psychological factors, including lack of social support and perceived lack of control, were found to be highly associated with an increased risk of the diseases. In fact, the effect of disease management programs (DMP) in patients diagnosed with chronic diseases were assessed in multiple studies to measure health-related quality of life (HR = QoL), which measured in the EuroQol 5-Dimension Questionnaire (EQ-5D) index score, also known as self-perceived health. Methods: The study was conducted using the Korea National Health and Nutrition Examination Survey (KNHANES) from 2007 to 2012 and through descriptive statistics and multiple linear regression to investigate the association of participation in DMP and the EQ-5D index score. Results: The results revealed that the subjects diagnosed with hypertension were shown to have a lower quality of life to those without the diagnosis ( P .05). Conclusion: Our study has assessed the association of DMP and EQ-5D index score in hypertensive patients only although it is still uncertain the effect of DMP on other chronic diseases therefore, further studies should be conducted to investigate the importance of DMP in Korea for the patients with such diseases in improving their quality of life.

Background Little is known about the risk of acquired disability diagnosed by a physician in relation to baseline BMI and weight change, particularly in the Asian population. Objective This study assessed the association of baseline BMI and weight change with incidence of disability. Methods This study included 331,900 individuals aged ≥40 years who participated in two health-screening programs since 2002 or 2003 and who were followed up until 2013. This study measured the baseline BMI and weight change for two years and estimated the adjusted hazard ratio (aHR) of the risk of acquired disability diagnosed by a physician using a Cox proportional hazards model. Results This study identified 1758 incident disability cases during an average follow-up period of 10.7 ± 1.3 years from baseline (9.1 ± 1.4 years from the follow-up health screening). Baseline underweight (BMI Conclusion This study demonstrated that baseline underweight and weight changes (both loss and gain) are associated with an increased risk of acquired disability.

This study aimed to compare the utilization of Alzheimer's disease (AD) treatments, donepezil, galantamine, rivastigmine, and memantine, in Korea with Australia and other countries with universal health coverage.Reimbursement criteria and the patent status of four AD treatments in Korea and Australia were reviewed. The monthly spending and utilization of the treatments were extracted from the national electronic database in Korea and Australia. The defined daily dose per 1000 elderly population per day (DDD/1000e/day) were calculated from July 2008 to June 2019. Annual cost trends of Norway and England were compared with Korea and Australia.With the highest share of the use of donepezil in both countries, the cost and utilization of AD treatments in Korea increased more rapidly and remained higher than Australia. The cost of AD treatments in Korea increased by 15.5% every year during the study period, while the spending of the same drugs in Australia decreased by 10.5% annually. The utilization in DDD/1000e/day of AD treatments in Korea increased by 18.3% annually compared with 1.4% in Australia. When compared with Norway and England, countries with similar universal health coverage (UHC) system and elderly polupation, the cost of AD treatments in Korea was still higher with the opposite trend from other countries.Despite the similar UHC systems, there were considerable differences in the post-market utilization of AD treatments in Korea from Australia and other countries. This results can be attributed to differences in re-assessment system, pricing and reimbursement policies, and prescribing culture. This study provides a baseline to explore more comprehensive cross-country studies on rational use of medicines.

Introduction This study investigates the association of smoking cessation and postcessation weight gain with the development of type 2 diabetes mellitus and hypertension. Methods A total of 96,524 individuals without diabetes mellitus and hypertension aged ≥20 years between 2006 and 2008 were included, with follow-up until December 31, 2015. Smoking status and weight changes were monitored for 2 years. Hazard ratios and 95% CIs were calculated for the respective risks of the 2 conditions. Analyses were completed in 2020. Results Compared with current smokers, the adjusted hazard ratios for the risk of type 2 diabetes and hypertension were 0.90 (95% CI=0.85, 0.96) and 1.00 (95% CI=0.95, 1.05) in recent quitters, 0.89 (95% CI=0.84, 0.95) and 0.92 (95% CI=0.88, 0.97) in long-term quitters, and 0.82 (95% CI=0.78, 0.86) and 0.92 (95% CI=0.89, 0.95) in never smokers. Compared with current smokers, the adjusted hazard ratios for the risk of type 2 diabetes and hypertension were 0.86 (95% CI=0.80, 0.93) and 0.98 (95% CI=0.92, 1.04) in recent quitters with no weight gain, 0.94 (95% CI=0.87, 1.03) and 1.00 (95% CI=0.94, 1.07) in those with 0.1–5 kg weight gain, 0.93 (95% CI=0.73, 1.19) and 1.14 (95% CI=0.96, 1.36) in those with 5.1–10 kg weight gain, and 1.49 (95% CI=0.84, 2.62) and 1.10 (95% CI=0.68, 1.77) in those with a weight gain of >10 kg. Conclusions Smoking cessation with no subsequent weight gain is associated with a reduced risk of developing type 2 diabetes. However, weight gain after smoking cessation attenuates the reduced risk of type 2 diabetes. The association between recent quitting and incident hypertension was nonsignificant, whereas long-term quitters had reduced risk of developing hypertension and type 2 diabetes.

This study analyzed the impact of visual impairment on socioeconomic and physical health status and its heterogeneity by severity of visual impairment. We used nationally representative cohort data based on Korean national health insurance claims (2002–2013), which were extracted for 11,030 persons (2206 visually impaired, 8824 control). This was restructured as monthly data for each person (person-month). Multivariate and ordered logistic regressions were conducted, and the pre-impairment status between the visually impaired and non-visually impaired people was adjusted by difference-in-difference (DiD) estimation. Focusing on medical aid (a public healthcare service assistance program for people who cannot afford health insurance premiums), the DiD estimate showed that the likelihood of receiving aid was higher among visually impaired compared with non-impaired people. Mildly and severely visually impaired people were more likely to be medical aid recipients than their counterparts. The severely visually impaired group was more likely to be unemployed. The visually impaired group were less likely to have no comorbidity. Our findings show that the socioeconomic and physical health status of visually impaired people is more likely to deteriorate than that of their non-visually impaired counterparts following onset of impairment.

South Korea is unique in that it leads global markets in R&D as well as production of biosimilar products and was the first market into which some biosimilar products were introduced. We analyzed the time trend of market penetration and simulated saved spending by biosimilars in South Korea. We pulled Korean National Health Insurance claims data from January 2012–December 2018 for second-generation biologics, including infliximab, rituximab, and trastuzumab, and examined the time trends of expenditure, utilization in defined daily dose, and price. We also assessed market penetration by biosimilars and simulated expenditure savings gained due to their introduction. We comparatively examined time trends and spending savings during the same period for selected small-molecule generic drugs to understand any specifics limited to biosimilars for time trends of market share and quantity-standardized prices. The market share for infliximab biosimilar plateaued at over 30%, which is smaller than the market penetration of esomeprazole (over 60%), a small-molecule comparator. Despite a shorter observation period, rituximab and trastuzumab biosimilars also showed larger utilization rates (12.89% and 13.93%, respectively) than infliximab (9.05%) in their second year after market entry. Infliximab was associated with approximately US $82–114 million expenditure savings over 6 years after its biosimilar entry to the market. Rituximab and trastuzumab biosimilars each also resulted in reduction in total spending by approximately US $9–14 million, in less than 2 years. Biosimilars captured the market rapidly, despite a heterogeneous uptake rate by product in South Korea. However, expansion of biosimilar use in the market and consequent expenditure savings need to be supported by pre-emptive policy measures to encourage price competition and boost utilization.

We explore the association with self-reported asthma and pulmonary function based on spirometry measurements using different measures to determine obesity because body mass index (BMI) is limited in not differentiating fat and muscle mass.A multi-year cross-sectional study using Korean National Health and Nutrition Examination Survey data was conducted between July 2008 and May 2011. A total of 9409 subjects were included in the final analysis.Obesity was associated with self-reported asthma and pulmonary function limitations mainly in adult women aged between 40 and 65 years and elderly men aged 65 or older. The association was stronger when the measurement of obesity was based on body fat percentage or waist-to-height ratio (WHtR), compared to BMI. There was a higher self-reported asthma risk among obese women according to the WHtR [odds ratio (OR) = 1.817, 95% CI: (1.208, 2.735)]. There was an increased risk of pulmonary function limitation with abdominal obesity [OR 1.418, 95% CI (1.020, 1.972)], weight-to-height ratio [OR 1.467, 95% CI (1.058, 2.034)], and obesity with regard to body fat percentage [OR 1.753, 95% CI (1.251, 2.457)] in adult women. In elderly men, obesity based on body fat percentage was associated with an increased risk of pulmonary function limitation [OR 1.93, 95% CI (1.098, 3.388)].Measures other than BMI should be examined when investigating the effect of obesity on self-reported asthma and pulmonary function limitation.

Background The dose response relationship of nine-year cumulative anticholinergic exposure and dementia onset was investigated using the Korean version anticholinergic burden scale (KABS) in comparison with the Anticholinergic Cognitive Burden Scale (ACB). We also examined the effect of weak anticholinergics in the prediction of dementia. Methods A retrospective case-control study was conducted comprising 86,576 patients after 1:2 propensity score matching using the longitudinal national claims database. For cumulative anticholinergic burden estimation, average daily anticholinergic burden score during the 9 years prior to dementia onset was calculated using KABS and ACB and categorized as minimal, Results Patients with high exposure according to KABS and ACB comprised 3.2 and 3.4% of the dementia cohort and 2.1 and 2.8% of the non-dementia cohort, respectively. Dose-response relationships were observed between anticholinergic burden and incident dementia. After adjusting covariates, compared with minimal exposure, patients with high exposure according to KABS and ACB had a significantly higher risk for incident dementia with aOR of 1.71 (95% confidence interval (CI) 1.55–1.87) and 1.22 (CI 1.12–1.33), respectively. With the exclusion of weak anticholinergics, the association became stronger, i.e., 1.41 (CI 1.14–1.75) with ACB whereas the association became slightly weaker with KABS, i.e., 1.60 (CI 1.38–1.86). Conclusion This study confirmed the dose response relationship for cumulative anticholinergic burden measured using the Korean specific anticholinergic burden scale with incident dementia.

ObjectiveThis study aimed to examine the association of employment status and income with self-rated health among waged workers with disabilities in South Korea.MethodsThis study used the Panel Survey of Employment for the Disabled from 2011 to 2015. A total of 951 waged workers with disabilities were selected as baseline subjects in 2011 and were followed up for 5 years. This study used a generalised linear mixed model after adjusting for covariates.ResultsAmong 951 waged workers with disabilities, the results showed that 39.3% of workers with disabilities reported poor self-rated health. Workers with disabilities with a precarious employment status and lower income were 1.22 (95% CI 1.21 to 1.23) and 1.81 (95% CI 1.80 to 1.83) times more likely to have poor self-rated health than those with permanent employment and higher income, respectively. A subgroup analysis found that precarious workers with disabilities in lower income households had higher possibilities of poor self-rated health.ConclusionThis study suggests that precarious employment and lower income of waged workers with disabilities are significantly associated with poor self-rated health compared with those with permanent jobs or higher income.

Previous studies reported that hearing impairment has been associated with depressive disorders, but little is known about the risk of newly diagnosed depression after hearing impairment diagnosed by a physician and registered with the government. We evaluated the risk of new-onset depressive disorders following hearing impairment in adults. We used data from the Korean National Health Insurance Service-National Sample Cohort and included adults with hearing impairment, and a comparison group without hearing impairment, selected by a 1:3 propensity score matching between 2004 and 2012. The dependent variable was a depressive disorder diagnosis. The hazard ratio of risk of depression was estimated using a Cox proportional hazard model. In the sample of 14,212 adults, 15.0% of people with hearing impairment (n = 3,553) experienced a depressive disorder following their hearing impairment. Those who had not experienced depression previously were more likely to develop a new-onset depressive disorder following hearing impairment than the comparison group. Male, female, old adults (60–74 years) and very-old adults (≥ 75 years) with hearing impairment were associated with an increased risk for a new-onset depressive disorders than their matched counterparts. These findings suggest a need for psychological support along with hearing rehabilitation, especially for older adults.

The current study explores the moderation of the relationship between obesity and labor market outcomes by direct employment efforts such as job hunting and job training of young adults. The study used data provided by the Korean Education and Employment Panel, a longitudinal data survey comprising middle and high school students from 2004 to 2015. Two dependent variables were assessed in this study: employment status and wage. The individual-level fixed effects were controlled. Despite having more direct employment efforts of either or both experience in job hunting and job training, compared to normal-weight counterparts, underweight men and overweight and obese women were reported to have a disadvantage in both dependent variables. Underweight men with job training experience were 12.02% less likely to be employed, while overweight and obese men had 6.80 times higher monthly wages when job training experience was accompanied compared to no such experience. For overweight and obese women, compared to that of their normal-weight counterparts, employment probability decreased by 4.78% per week-increase in job hunting, by 2.81% if any experience in job hunting. For underweight women, compared to that of their normal-weight counterparts, employment probability increased by 4.56 times per week-increase in job hunting and by 5.59 times if experience in job hunting, and by 6.96% if experience in job training. The results indicate that employment efforts do not fully moderate the presence of obesity penalty for labor market outcomes on those early in their careers.

Type 2 diabetes mellitus (T2DM) is a chronic disease that requires long-term therapy and regular check-ups to prevent complications. In this study, insurance claim data from the National Health Insurance Service (NHIS) of Korea were used to investigate insulin use in T2DM patients according to the economic status of patients and their access to primary physicians, operationally defined as the frequently used medical care providers at the time of T2DM diagnosis. A total of 91,810 participants were included from the NHIS claims database for the period between 2002 and 2013. The utilization pattern of insulin was set as the dependent variable and classified as one of the following: non-use of antidiabetic drugs, use of oral antidiabetic drugs only, or use of insulin with or without oral antidiabetic drugs. The main independent variables of interest were level of income and access to a frequently-visited physician. Multivariate Cox proportional hazards analysis was performed. Insulin was used by 9,281 patients during the study period, while use was 2.874 times more frequent in the Medical-aid group than in the highest premium group [hazard ratio (HR): 2.874, 95% confidence interval (CI): 2.588-3.192]. Insulin was also used ~50% more often in the patients managed by a frequently-visited physician than in those managed by other healthcare professionals (HR: 1.549, 95% CI: 1.434-1.624). The lag time to starting insulin was shorter when the patients had a low income and no frequently-visited physicians. Patients with a low level of income were more likely to use insulin and to have a shorter lag time from diagnosis to starting insulin. The likelihood of insulin being used was higher when the patients had a frequently-visited physician, particularly if they also had a low level of income. Therefore, the economic statuses of patients should be considered to ensure effective management of T2DM. Utilizing frequently-visited physicians might improve the management of T2DM, particularly for patients with a low income.

This paper assesses the relationship between obesity and the job market by focusing on young adults early on in their careers, while considering the factor of gender and the individuals&rsquo, job qualifications. This study extracted data on high school students for four years from the Korean Education and Employment Panel (from 2010 to 2013), a nationally representative dataset comprising of 2000 middle school students and 4000 high school seniors. The individual-level fixed effects were controlled using conditional logistic regression models and an ordinary least squares model. Obese and overweight men were 1.46 times more likely to be placed in professional jobs and had 13.9% higher monthly wages than their normal-weight counterparts. However, obese and overweight women were 0.33 times less likely to have service jobs, earned 9.0% lower monthly wages, and half as likely to have jobs with bonuses than that of their normal-weight counterparts. However, such penalty among women was found only when they had none of the assessed job market qualifications. Given that initial jobs and job conditions have lingering impacts in long-term job performance, the cumulative penalty for overweight or obesity could be more substantial for young adults in particular.

Background This study aimed to identify the effect of the overweight or obesity (OWOB) trajectory on current health care expenditure in South Korea. Methods Ten years of publicly released data (2002–12) were obtained in 2016 from a retrospective cohort of National Health Insurance System claims. This study included 51,844 adults (aged 30–59 years in 2002) and 21,196 elderly adults (aged ≥ 60 years in 2002). Results Compared with adults who maintained normal weight (NW), higher yearly total health expenditures were estimated for adults who lost weight over the 10-year period: by 11.5% (95% confidence interval (CI): 0.18–22.96%) when changing from NW to underweight (UW) and 6.2% (95% CI: 0.47–12.01%) from OWOB to UW/NW. Elderly adults had higher health expenditures when they lost weight by 14.0% (95% CI: 0.37–27.70%) from NW to UW and 6.8% (95% CI: 0.13–13.51%) from OWOB to UW/NW compared with when they maintained NW. Conclusions These findings indicate the importance of early intervention to control OWOB, particularly because people in late adulthood have greater health care needs for reasons other than OWOB.

Antiretroviral treatment (ART) adherence is highlighted in management of patients living with human immunodeficiency virus. In South Korea, ART medication research has rarely been conducted due to the low economic burden associated with government-funded treatment. This cross-sectional study aimed to compare the pill burden impact between ART regimen compliance and HIV-RNA viral load suppression. Data were collected from 2008 to 2016 at a general hospital in South Korea. A total of 210 HIV/AIDS treatment-naïve patients were grouped as follows: single-tablet regimen (STR, one tablet/day), mild pill burden (two-four tablets/day), and heavy pill burden (≥ five tablets/day). Patients were analyzed according to gender, age at index date, medical insurance type, comorbidities, depression, HIV/AIDS disease burden as indicated by HIV-RNA viral load and CD4, and laboratory variables. In a multivariate logistic regression model, the STR group demonstrated adherence 5.10 times more often than the heavy pill burden group. Females and patients with an initial viral load of 500,000 or more were 0.090- and 0.040-fold less adherent to the ART regimen. Among these patients, 95% or more of the MPR group were 7.38 times more likely to have a lower limit of detection (LLOD) of viral load suppression. The highest initial viral load group was 0.090-fold less likely to have an LLOD than the reference group. These results suggest that a single-tablet regimen could improve medication adherence and the clinical virologic outcome. Therefore, general population research on ART adherence and polypharmacy is needed.

This study analyzed factors contributing to increases in the actual sales volumes relative to forecasted volumes of drugs under price-volume agreement (PVA) policy in South Korea. Sales volumes of newly listed drugs on the national formulary are monitored under PVA policy. When actual sales volume exceeds the pre-agreed forecasted volume by 30% or more, the drug is subject to price-reduction. Logistic regression assessed the factors related to whether drugs were the PVA price-reduction drugs. A generalized linear model with gamma distribution and log-link assessed the factors influencing the increase in actual volumes compared to forecasted volume in the PVA price-reduction drugs. Of 186 PVA monitored drugs, 34.9% were price-reduction drugs. Drugs marketed by pharmaceutical companies with previous-occupation in the therapeutic markets were more likely to be PVA price-reduction drugs than drugs marketed by firms with no previous-occupation. Drugs of multinational pharmaceutical companies were more likely to be PVA price-reduction drugs than those of domestic companies. Having more alternative existing drugs was significantly associated with higher odds of being PVA price-reduction drugs. Among the PVA price-reduction drugs, the increasing rate of actual volume compared to forecasted volume was significantly higher in drugs with clinical usefulness. By focusing the negotiation efforts on those target drugs, PVA policy can be administered more efficiently with the improved predictability of the drug sales volumes.

Introduction Necrotizing fasciitis (NF) is a rare but fatal disease, and there is no known annual incidence of NF in Korea. The aim of this study was to investigate the incidence and seasonal variation of NF in Korea. Methods We analysed claims from the nationwide Korean Health Insurance Review and Assessment Service database. Patients who were hospitalized with an NF diagnosis code and received surgical intervention were classified as NF cases. Poisson regression models were used to assess the relationships of incidence rates with year, age and sex. A multivariate Poisson regression model was used to investigate variations in monthly NF incidence trends. Results From 2012 to 2017, the overall average annual NF incidence rate was found to be 0.86 per 100 000 population. NF incidence increased with age and was 2.5 times higher among males across all age groups. Two-thirds of cases occurred among patients with diabetes. The peak NF incidence occurred during the summer. Multivariate Poisson regression modelling using national meteorological variables suggested that mean temperatures and number of NF cases in the previous month were associated with the number of NF cases in the current month. Discussion Clinicians should consider NF when encountering an elderly man with diabetes during the summer.

Introduction Trivalent influenza vaccines (TIVs) are currently reimbursed for subjects aged ≥ 65 years and children between 6 and 59 months of age under a national immunization program in South Korea. Quadrivalent influenza vaccines (QIVs) are expected to address the potential problem of influenza B-lineage mismatch for TIVs. Objective The objective of this analysis was to compare the cost effectiveness of QIV versus TIV in children aged 6–59 months and older adults ≥ 65 years of age in South Korea. Methods A 1-year static population model was employed to compare the costs and outcomes of a QIV vaccination program compared with TIV in children aged 6–59 months and older adults ≥ 65 years of age in South Korea. Influenza-related parameters (probabilities, health resource use, and costs) were derived from an analysis of the National Health Insurance System claims database between 2010 and 2013 under a broad and narrow set of International Classification of Diseases, Tenth Revision (ICD-10) codes used to identify influenza. Other inputs were extracted from published literature. Incremental cost-effectiveness ratios (2016 South Korean Won [KRW] per quality-adjusted life-year [QALY] gained) were estimated using a ‘limited’ societal perspective as per the Korean pharmacoeconomic guidelines. QALYs lost due to premature mortality were discounted at 5% annually. Results For both age groups combined, under the narrow definition of influenza, QIV is expected to prevent nearly 16,000 (2923 in children and 13,011 in older adults) medically attended influenza cases, nearly 8000 (672 in children, 7048 in older adults) cases of complications, and over 230 (0 in children, 238 in older adults) deaths annually compared with TIV. The impact of using QIV versus TIV in this setting translates into savings of KRW 24 billion (KRW 0.6 billion in children, KRW 23.4 billion in older adults) in annual medical costs, and over 2100 (18 in children, 2084 in older adults) QALYs. Under the broad definition, the corresponding results are over 190,000 (50,697 in children, 140,644 in older adults) influenza cases, over 37,000 (12,623 in children, 24,526 in older adults) complications, 270 deaths (0 in children, 270 in older adults), KRW 94.22 billion (KRW 16 billion in children, KRW 78.2 billion in older adults), and over 3500 QALYs saved (316 in children, 3260 in older adults). Conclusion The use of QIV over TIV was estimated to not be cost effective in children 6–59 months of age, but cost saving in older adults, using the narrow definition of influenza; however, QIV use was cost saving in both age groups using the broad definition. QIV is expected to yield more benefits in older adults ≥ 65 years of age than in children aged 6–59 months due to higher influenza-related mortality and costs among the older adults. Further analyses considering the indirect effects of influenza vaccination in children are required. Electronic supplementary material The online version of this article (10.1007/s40273-018-0715-5) contains supplementary material, which is available to authorized users.

It has previously been reported that an individual's body mass index (BMI) contemporaneously penalizes wages for women, but has no effect and sometimes rewards wages for men. In young adults, we estimate the association of BMI status with initial wages to assess whether initial BMI at the beginning of an individual's career affects initial and later earnings. We pooled data from 388 men and 305 women, aged 20-40 years, with BMI information for the first year of employment, using the Korean Labor and Income Panel Study. A labor market penalty for a higher BMI among women was found only for overweight or obese segments, particularly those with relatively higher monthly wages. Meanwhile, a higher BMI in underweight or normal weight segments could reward employment probability for women and monthly wages for men. Such rewards of relatively higher monthly wages were also estimated for men in the overweight segment. Our findings suggest discrimination as one factor penalizing higher BMI in the labor market.

Background : The diagnosis-related group-based prospective payment programme was introduced in Korea in 1997 as a pilot programme to control health spending. In July 2013, the programme was implemented throughout the nation. The aim of our study is to evaluate the relationship between quality of care and market competition following the introduction of the new payment system in Korea. Methods : We conduct an observational analysis using National Health Insurance claim data from 2011 to 2014. We analyse data on readmission within 30 days, length of stay, and number of outpatient visits for 1742 hospitals and 821 912 cases. We use a generalized estimating equation model to evaluate readmission within 30 days and number of outpatient visits and a multi-level regression model to assess length of stay. Results : Total readmission within 30 days is 10 727 (1.3%). High competition areas present a lower risk of readmission [odds ratio (OR): 0.95, P : 0.0277], a longer length of stay (1%, P < 0.0001), and an increased number of outpatient visits (Relative Risk: 1.11, P : 0.0011) as compared with moderate competition areas. Risk of readmission is higher in low competition areas as compared with moderate competition areas (OR: 1.21, P < 0.0001). Conclusion: The effects of the introduction of the new payment system differed by degree of market competition. Thus, evaluation about the effect of new payment system on hospital performance should be measured in combination with the degree of hospital market structure.

Objectives We analyzed the effect of the outpatient prescription incentive program and price cuts of listed medicines in South Korea on prescription drug expenditures and prescription behaviors, focusing on antibiotics for the most common infectious diseases. Methods We used the National Health Insurance claims data from January 1, 2009 through December 31, 2012. For 1625 primary clinics randomly sampled, we included all claims with principal diagnoses of acute upper respiratory tract infections (URTIs, J00–J06), acute lower respiratory tract infections (LRTIs, J20–J22), or otitis media (H65, H66). An interrupted time-series analysis was conducted. Results Pharmaceutical spending per claim dropped immediately after the outpatient prescription incentive program only for otitis media (adults), but the secular trend shifted downward after the incentive program for all target diseases. The incentive program lowered the trend of antibiotic prescribing rate in otitis media (adults). The program was associated with an increase of the number of antibiotics prescribed in URTI (adults) and LRTI (children) and decrease in otitis media (adults). The broad markdown of drug prices reduced pharmaceutical expenditures immediately for all diseases, but without lasting effect. Conclusion The direct financial incentives to physicians to reduce in prescription spending had the intended effect over time and can be an important tool to improve pharmaceutical spending management.

Objectives: The goal of this study was to examine the association of various demographic and socioeconomic factors with risk factors for chronic kidney disease (CKD). Methods: We used nationally representative pooled data from the Korea National Health and Nutrition Examination Survey (KNHANES), 2007–2013. We estimated the glomerular filtration rate (GFR) using the Modification of Diet in Renal Disease equation. We defined CKD as a GFR < 60 mL/min/1.73 m 2 , and 1304 of the 45 208 individuals included in the KNHANES were found to have CKD by this definition. The outcome variable was whether individual subjects adhered to the CKD prevention and management guidelines recommended by the Korea Centers for Disease Control and Prevention. The guidelines suggest that individuals maintain a normal weight, abstain from alcohol consumption and smoking, manage diabetes and hypertension, and engage in regular exercise in order to prevent and manage CKD. Results: This study found that individuals with CKD were more likely to be obese and have hypertension or diabetes than individuals without CKD. In particular, male and less-educated CKD patients were less likely to adhere to the guidelines. Conclusions: Although the prevalence of CKD, as indicated by the KNHANES data, decreased from 2007 to 2013, the prevalence of most risk factors associated with CKD fluctuated over the same time period. Since a variety of demographic and socioeconomic fac tors are related to the successful implementation of guidelines for preventing and managing CKD, individually tailored prevention activities should be developed.

Objectives This study examined the influence of home and school environments, and individual health-risk behaviours on body weight outcomes in Korean adolescents. Study design This was a cross-sectional observational study. Methods Quantile regression models to explore heterogeneity in the association of specific factors with body mass index (BMI) over the entire conditional BMI distribution was used. A nationally representative web-based survey for youths was used. Results Paternal education level of college or more education was associated with lower BMI for girls, whereas college or more education of mothers was associated with higher BMI for boys; for both, the magnitude of association became larger at the upper quantiles of the conditional BMI distribution. Girls with good family economic status were more likely to have higher BMIs than those with average family economic status, particularly at the upper quantile of the conditional BMI distribution. Attending a co-ed school was associated with lower BMI for both genders with a larger association at the upper quantiles. Substantial screen time for TV watching, video games, or internet surfing was associated with a higher BMI with a larger association at the upper quantiles for both girls and boys. Dental prevention was negatively associated with BMI, whereas suicide consideration was positively associated with BMIs of both genders with a larger association at a higher quantile. Conclusions These findings suggest that interventions aimed at behavioural changes and positive parental roles are needed to effectively address high adolescent BMI.

Background The prevalence of dyslipidemia, particularly hypercholesterolemia, has been reported to increase after pregnancy and menopause in Korea. This suggests the importance of the management of dyslipidemia in women for preventing cardiovascular diseases. Objective This study aimed to examine the association of breastfeeding with 5 subtypes of dyslipidemia in Korean women aged over 20 years, by using the nationally representative Korea National Health and Nutrition Examination Survey 2010–2014. Methods Ordinary least square regression and ordered logistic regression analyses were used to determine the association between breastfeeding duration and dyslipidemia. Results The likelihood of having low-density lipoprotein cholesterol (LDL-C) disorder decreased by 16% in the group that breastfed for more than 24 months (odds ratio, 0.84; 95% confidence interval, 0.75–0.95) compared with the group that did not breastfeed. The likelihood of having non–high-density lipoprotein cholesterol (non-HDL-C) disorder was significantly reduced by 25% when the breastfeeding duration was more than 24 months (odds ratio, 0.75; 95% confidence interval, 0.64–0.87). The tendency toward developing disorders of total cholesterol (TC), LDL-C, and non-HDL-C decreased as the duration of breastfeeding increased, particularly among women aged 30–39 years. Conclusion Breastfeeding duration was negatively correlated with dyslipidemia in terms of TC, LDL-C, non-HDL-C, and triglycerides. Long-term breastfeeding was associated with the prevalence of dyslipidemia-TC, LDL-C, non-HDL-C, and TG disorders, in particular.

Background Inappropriate antibiotic use significantly contributes to antibiotic-resistance, resulting in reduced antibiotic efficacy and increasing physical burden and cost of disease. The goal of this study was to explore antibiotic usage patterns in South Korea using 2007–2014 health insurance claims data. Methods We used the Health Insurance Review & Assessment Service data, which represents nearly the entire population of South Korea, to discern patterns in antibiotic prescribing practices. The daily dose, as defined by the World Health Organization ([defined daily doses]/1000 inhabitants/day, [DID]), was used as a measure of antibiotic use. Subgroup analyses were performed on the basis of patient characteristics (sex, age, and disease) and provider characteristics (type of medical institution). Results Antibiotic use in DID increased from 23.5 in 2007 to 27.7 in 2014. The ≤ 6 years old age group showed the highest level of usage at 59.21 DID in 2014, and showed an increasing trend each year. DIDs of beta-lactam antibacterials, penicillins (J01C), other beta-lactam antibacterials (J01D), lincosamides and streptogramins (J01F), quinolone antibacterials (J01M), and other antibacterials (J01X) increased over time. Conclusion This study provides valuable statistics regarding antibiotic usage in South Korea; this is important for guiding health policy with regard to antibiotic usage. There is a need for further study exploring antibiotics use and resistance.

This study aimed to investigate the prevalence of potential unnecessary injection (PUNI) and to identify factors associated with frequent PUNI uses. Population-based National Health Insurance claims data for outpatient health care settings during the six month period from July to December 2011 were retrospectively reviewed. Patients aged 18-80 without severe diseases and visited healthcare centers more than 25 times during study period were included. PUNI was defined as injection used where substitutable oral agents were available and where injection uses are not warranted. A total of 801,532 patients were included for this analysis. Among them, 29.0 % were frequent PUNI user defined as ≥10 PUNI used during the study period. In multivariate logistic regression results revealed significant associations between frequent PUNI use and several patient and healthcare utilization factors. Women than men, elderly than younger people, residents in rural areas than in big cities, and more frequent visitors to healthcare centers than less frequent visitors were more likely to be frequent PUNI users. Larger number of healthcare center utilized and higher out-of-pocket expense level showed significant lower risks of frequent PUNI uses. Identified factors associated with frequent PUNI use in this study could be the targets to develop programs for reducing injection overuse.

Objective To investigate the association between potentially inappropriate medicine (PIM) use, defined using the American Geriatric Society (AGS) 2012 Beers criteria, and the risk of hospitalization or emergency department (ED) visits in elderly patients, and to examine the most frequently used PIMs among patients with adverse outcomes. Design/setting This was a retrospective study using National Health Insurance claims data from 2010 to 2012. Intervention(s) Elderly patients who took PIMs are compared to those who were not taking PIMs. Study participants Elderly patients (n = 79 552) who visited medical institutions in Jeju Island during 2011. Main outcome measure Hospitalization and ED visits were evaluated according to whether the patients took PIMs during the study period. The most frequent medications used by the PIM group were also investigated. Results The likelihood of hospitalization was higher in older patients who took at least one PIM than in those who were not taking PIMs during the study period (odds ratio 2.25, 95% confidence interval 2.09-2.44). Patients taking PIMs were more likely to visit EDs (odds ratio 1.59, 95% confidence interval 1.50-1.67). Among patients who were hospitalized or visited EDs, 45.5% had taken at least one PIM on that day. The most commonly used PIMs included chlorpheniramine maleate, diazepam, metoclopramide HCl and diclofenac sodium. Conclusion Our findings indicate that PIM use can lead to negative health consequences, providing further evidence of the inappropriateness of these medications. Thus, pharmaceutical policies regarding PIM use may need to be implemented for elderly adults in Korea.

Purpose. To explore the relationships of selected health behaviors to medication adherence. Design. A retrospective cohort study. Setting. Data from Korean national health insurance claims between January 2010 and June 2011. Subjects. Patients aged 65 years and older with hypertension (N = 662,170), hyperlipidemia (N = 244,702), or diabetes (N = 179,285). Measures. Medication adherence as a medication possession ratio from January to June 2011 as a dependent variable. The waist circumference (cm) and the body mass index (weight in kilogram divided by height in meter squared) as a marker for obesity. Smoking, drinking, and physical activity as main independent variables. Analysis. A multivariate logistic regression. Results. Nonobese patients, as based on the waist circumference, were more likely to adhere to their medication (by 8.9% for hypertension, 6.2% for diabetes, and 3.5% for hyperlipidemia). Current smokers were less likely to adhere to their medication (by 8.7% for hypertension and 6.8% for diabetes), and moderate and heavy drinkers were also less likely to show medication adherence for diabetes (by 12.9% and 6.4%). Mild physical activity was related to a 1.1% to 1.8% increase in the likelihood of medication adherence across the three disease groups. Conclusion. Health promotion programs for self-care health behaviors of elderly patients should emphasize good medication adherence to achieve successful self-management of diseases.

Skipping breakfast can be potentially harmful because breakfast consumption is considered one of the important health-related behaviors that benefit physical and mental health. As the rate of depression has increased recently, we investigated the association between the frequency of eating breakfast and depression in adults. We obtained the data from the 2013 Korean Community Health Survey; a total of 207,710 survey participants aged 20 years or over were studied. Participants were categorized into three groups by the frequency of breakfast consumption as follows: “seldom,” “sometimes,” and “always.” We performed a multiple logistic regression to investigate the association between breakfast consumption and depressive mood. Subgroup analyses were conducted by stratifying socioeconomic variables controlling for variables known to be associated with depressive symptoms. Participants who had breakfast seldom or sometimes had higher depressive symptoms than those who always ate breakfast (“seldom”: OR = 1.43, 95% CI 1.36–1.52; “sometimes”: OR = 1.32, 95% CI 1.23–1.40). Subgroup analyses showed that this association was more marked in those who were 80 years or older, those who had low household income, or those with elementary school education level or less. The result of this study suggests that lack of breakfast consumption is associated with depression among adults with different socioeconomic factors.

We assessed the impact on physician prescription behaviors of an outpatient prescription incentive program providing financial rewards to primary care physicians for saving prescription costs in South Korea. A 10% sample of clinics (N = 1,625) was randomly selected from all clinics in the National Health Insurance claims database for the years 2009–2012, and all claims with the primary diagnosis of peptic ulcer or gastro-esophageal reflux diseases were extracted from those clinics’ data. A clinic-level random-effects model was used. After the program, clinics in general medicine showed a lower prescription rate (by 0.8 percentage points), lower number of medicines prescribed (by 0.02), lower prescription duration (by 0.15 days), and lower drug expenditure per claim (by 740 won). Small clinics on the

The Price-Volume Agreement Program (PVAP) was promulgated in 2007 in South Korea as the first attempt to adjust drug pricing according to total consumption in order to contain drug expenditure. This study was designed to assess the impact of the PVAP on diabetes drug expenditure for a period of a 10-year period (2003-2012) using claims data from the National Health Insurance Service. We estimated a multilevel mixed-effects linear regression model by comparing the level of total monthly diabetes drug expenditure for drugs subject to PVAP and existing drugs after adjusting the average differences in drug expenditure before and after the PVAP. The monthly total expenditure for drugs that were newly listed through the PVAP (negotiation drugs) was 7.03% higher on average compared to that for existing drugs, controlling for the baseline differences in expenditure before and after the PVAP. This increase was observed in all four subgroups of diabetes drugs, including sitagliptin, vildagliptin, exenatide, and others. The growth rate of total diabetes drug expenditure was reduced after the PVAP despite the sustained escalation of expenditure levels, which may imply that the PVAP has the potential to be an effective tool for drug expenditure control in the long term.

OBJECTIVE This study was designed to investigate patient responses to a medication counseling intervention program piloted by the National Health Insurance Service (NHIS), the national health insurer in Korea, to improve medication management in patients with hypertension, hyperlipidemia, or diabetes. METHODS AND MATERIALS Interventions were conducted from July to September 2013 through direct mailing followed by two telephone-initiated counseling sessions for the medication discontinuation group (< 80% medication possession ratio (MPR) and ≥ 2 months of discontinuation) and the medication over-possession group (≥ 150% MPR). The telephone intervention was applied through two models: model 1 (counseling by NHIS staff only) and model 2 (counseling by NHIS staff with contract-based working pharmacists in community pharmacies). Multivariate logistic regression analysis was performed to identify factors affecting favorable responses of patients to the telephone-initiated intervention. Patient responses to the telephone-initiated intervention were evaluated by a counselor. RESULTS In all, 891 patients were counseledvia telephone. Patient responses to the telephone-initiated intervention were favorablein 57.6%, neutral in 17.4% and not favorable in 24.9% overall. Counseling by NHIS staff together with pharmacists (model 2) produced more favorable responses from patients than counseling by NHIS staff alone (model 1) (OR 2.73, 95% CI 1.97 - 3.77). CONCLUSION Our findings of favorable responses to interventions support a personalized approach by the NHIS to improve patient behavior for medication adherence.

Background Overweight/obesity is a growing health risk in Korea. The impact of overweight/obesity on pharmaceutical expenditure can be larger if individuals have multiple risk factors and multiple comorbidities. The current study estimated the combined effects of overweight/obesity and other unhealthy behaviors on pharmaceutical expenditure. Methods An instrumental variable quantile regression model was estimated using Korea Health Panel Study data. The current study extracted data from 3 waves (2009, 2010, and 2011). Results The final sample included 7148 person-year observations for adults aged 20 years or older. Overweight/obese individuals had higher pharmaceutical expenditure than their non-obese counterparts only at the upper quantiles of the conditional distribution of pharmaceutical expenditure (by 119% at the 90th quantile and 115% at the 95th). The current study found a stronger association at the upper quantiles among men (152%, 144%, and 150% at the 75th, 90th, and 95th quantiles, respectively) than among women (152%, 150%, and 148% at the 75th, 90th, and 95th quantiles, respectively). The association at the upper quantiles was stronger when combined with moderate to heavy drinking and no regular physical check-up, particularly among males. Conclusion The current study confirms that the association of overweight/obesity with modifiable unhealthy behaviors on pharmaceutical expenditure is larger than with overweight/obesity alone. Assessing the effect of overweight/obesity with lifestyle risk factors can help target groups for public health intervention programs.

In November 2006, 727 combination drugs in 24 therapeutic classes were delisted in the national formulary in Korea to reduce the country's pharmaceutical expenditure, making these 727 drugs non-reimbursable. This study examines the effects of this delisting on national health insurance expenditures for pharmaceuticals. An interrupted time series analysis was conducted for the period from January 2005 to August 2007 by using administrative claims from Korea's National Health Insurance. The main outcome variable was the total pharmaceutical expenditure measured as a whole and based on the level of health care institutions and therapeutic classes. Comparison between exposure group (delisted drugs) and non-exposure group (listed drugs) were done. No changes in the level of or trend in the total pharmaceutical expenditure were detected. However, the delisting reduced pharmaceutical expenditures in clinics. Delisting effects were also observed according to therapeutic classes of drugs. The results indicate that any delisting should take into account the type of drug.

The current study explores the association between body mass and job quality, a composite measurement of job characteristics, for adults. We use nationally representative data from the Korean Labor and Income Panel Study for the years 2005, 2007, and 2008 with 7282 person-year observations for men and 4611 for women. A Quality of Work Index (QWI) is calculated based on work content, job security, the possibilities for improvement, compensation, work conditions, and interpersonal relationships at work. The key independent variable is the body mass index (kg/m 2 ) splined at 18.5, 25, and 30. For men, BMI is positively associated with the QWI only in the normal weight segment (+0.19 percentage points at the 10th, +0.28 at the 50th, +0.32 at the 75th, +0.34 at the 90th, and +0.48 at the 95th quantiles). A unit increase in the BMI for women is associated with a lower QWI at the lower quantiles in the normal weight segment (−0.28 at the 5th, −0.19 at the 10th, and −0.25 percentage points at the 25th quantiles) and at the upper quantiles in the overweight segment (−1.15 at the 90th and −1.66 percentage points at the 95th quantiles). The results imply a spill-over cost of overweight or obesity beyond its impact on health in terms of success in the labor market.