Hemodialysis facility star rating affects mortality in chronic hemodialysis patients: a longitudinal observational cohort study.

BACKGROUND: Many countries have their own hemodialysis (HD) quality assurance programs and star rating systems for HD facilities. However, the effects of HD quality assurance programs on patient mortality are not well understood. Therefore, in the present study, the effects of the Korean HD facility star rating on patient mortality in maintenance HD patients were evaluated. METHODS: This longitudinal, observational cohort study included 35,271 patients receiving HD treatment from 741 facilities. The fivestar ratings of HD facilities were determined based on HD quality assessment data from 2015, which includes 12 quality measures in structural, procedural, and outcome domains. The patients were grouped into high (three to five stars) and low (one or two stars) groups based on HD facility star rating. Cox proportional hazards model was used to evaluate the effects of star rating on patient mortality during the mean follow-up duration of 3 years. RESULTS: The patient ratio between high and low HD facility star rating groups was 82.0% vs. 18.0%. The patients in the low star rating group showed lower single-pool Kt/V and higher calcium and phosphorus levels compared with subjects in the high star rating group. After adjusting for sociodemographic and clinical parameters, the HD facility star rating independently increased the mortality risk (hazard ratio, 1.11; 95% confidence interval, 1.04-1.18; p = 0.002). CONCLUSION: The HD facilities with low star rating showed higher patient mortality.

Clinical outcomes among hemodialysis patients with atrial fibrillation: a Korean nationwide population-based study.

BACKGROUND: The number of patients requiring dialysis is increasing worldwide, and the atrial fibrillation and atrial flutter (AF) prevalence among hemodialysis (HD) patients is higher than in the general population. There have been no studies of Korean AF patients undergoing HD that investigated how AF affects outcomes, such as all-cause mortality, hospitalization, and stroke events. We conducted a large-scale retrospective cohort study with data from the National Health Insurance System to determine how AF affects these outcomes. METHODS: In 2013, the Health Insurance Review and Assessment service, a Korean national health insurance scheme, collected data from 21,839 HD patients to evaluate the adequacy of dialysis centers. All-cause mortality, hospitalization, and stroke events were compared between patients with and without AF. Sub-analyses compared these outcomes between AF patients receiving warfarin and those not receiving warfarin. RESULTS: Cox regression analysis found that AF was a significant risk factor for death from any cause (hazard ratio [HR], 1.356; 95% confidence interval [CI], 1.222-1.506; p < 0.001), hospitalization (HR, 1.323; 95% CI, 1.225-1.430; p < 0.001), and hemorrhagic stroke (HR, 1.500; 95% CI, 1.050-2.141; p = 0.026). AF was not significantly associated with an increased risk of ischemic stroke. The use of warfarin was significantly associated with hemorrhagic stroke incidence (HR, 1.593; 95% CI, 1.075-2.360; p = 0.020), while there was no significant correlation between warfarin treatment and all-cause mortality, hospitalization, and ischemic stroke. CONCLUSION: This cohort study of Korean dialysis patients showed that AF was a risk factor for multiple outcomes among HD patients.

Health Insurance Status Is Related to Risk of Mortality and Hospitalization in Korean Maintenance Hemodialysis Patients: A Longitudinal Cohort Study.

BACKGROUND: There has been an increasing incidence of hemodialysis (HD) due to old age and comorbid condition such as diabetes. In general, socioeconomic status (SES) is known as one of the most important risk factors for patient mortality and morbidity. Whether low SES is associated with poorer outcome in HD patients is controversial. This study was performed to evaluate the association of health insurance status as a proxy indicator for SES upon mortality and hospitalization in maintenance HD patients. METHODS: We used HD-quality assessment data from the year of 2015 for collecting demographic and clinical data. The subjects were classified into Medical Aid (MA) recipients (low SES) and National Health Insurance (NHI) beneficiary (high SES). We analyzed mortality and hospitalization risk based on health insurance status using Cox proportional hazard model. A total of 35,454 adult HD patients ≥18 years old who received HD treatment more than twice weekly were included in the analysis. RESULTS: The ratio between MA recipient and NHI beneficiary was 76.7 versus 23.3%. The MA recipient group demonstrated younger age and lower proportion of female, diabetes, hypertension, and cerebrovascular accidents compared to the NHI beneficiary group. After adjusting for age, gender, comorbidity, and laboratory parameters, the MA recipient group showed a significantly higher mortality risk compared to the NHI beneficiary group (hazard ratio 1.073 [1.009-1.14], p = 0.025). The MA recipient group was also an independent risk factor for hospitalization after adjusting for age, gender, comorbidities, and laboratory parameters (hazard ratio 1.142 [1.108-1.178], p < 0.001). CONCLUSION: Low SES as measured by health insurance status was associated with an increased risk of patient mortality and hospitalization in Korean maintenance HD patients.

Impact of chronic kidney disease on mortality: A nationwide cohort study.

BACKGROUND: Mortality is higher in patients with chronic kidney disease (CKD) than in the general population, but little information is available on CKD-related mortality that is representative of the Korean population. Our objective was to investigate mortality risk in Korean patients with CKD. METHODS: We identified patients with incident CKD who had not undergone dialysis or kidney transplantation between January 1, 2003 and December 31, 2007 in Korea using the database of the Korean National Health Insurance Service-National Sample Cohort, and stratified the population into the following three groups: group 1 (n = 1,473), controls; group 2 (n = 2,212), patients with diabetes or hypertension, but without CKD; and group 3 (n = 2,212), patients with CKD. We then monitored them for all-cause mortality until December 2013. RESULTS: A total of 1,473 patients were included in this analysis. During the follow-up period, 941 patients in group 3 died (134 deaths/1,000 person-years) compared with 550 deaths in the group 2 (34 deaths/1,000 person-years) and 459 deaths in group 1 (30 deaths/1,000 person-years). The rate ratio for mortality rate was 4.5, and the hazard ratio for mortality was 4.88 (95% confidence interval [CI], 4.36-5.47, P < 0.001) in patients in group 3 compared with age- and sex-matched controls (group 1). The rate ratio for mortality rate was 4.0, and the hazard ratio for mortality was 4.36 (95% CI, 3.92-4.85, P < 0.001) in patients in group 3 compared with patients in group 2. CONCLUSION: In this nationally representative sample cohort, excess mortality was observed in Korean patients with incident CKD.

Effect of patient solicitation on mortality among patients receiving hemodialysis in Korea.

BACKGROUND: There is concern that overcompetition and illegal activities such as patient solicitation by some dialysis units may threaten patients' health in Korea. Therefore, we investigated the effect of nephrologists' patient-soliciting activity on hemodialysis practices and patients' survival using the Korean Health Insurance Review and Assessment Service database. METHODS: We selected 19 soliciting hemodialysis facilities and matched them with 19 non-soliciting facilities located nearby to eliminate location bias. Soliciting behavior was defined as the reduction of medical fees or providing money to attract dialysis patients. RESULTS: A total of 2,231 incident dialysis patients were included and followed for a median of 37.2 months. Soliciting facilities had a lower percentage of nephrologists, a higher average daily number of hemodialysis patients per physician, and a higher number of hemodialysis patients per nurse compared with non-soliciting facilities. Survival analysis showed that the crude mortality was significantly higher in patients treated in soliciting facilities than in those treated in non-soliciting facilities, even after adjustment for the effects of many other independently predictive covariates. CONCLUSIONS: This study demonstrated that in Korea, the overall mortality rate in incident dialysis patients was higher in those attending soliciting facilities than in those attending non-soliciting facilities.

Fracture risk in chronic kidney disease: A Korean population-based cohort study.

BACKGROUND: Chronic kidney disease (CKD)-mineral and bone disorder (MBD) and fracture risk are both closely related to declining renal function. Controlling hyperphosphatemia with phosphate binders is a basic principle of CKD-MBD treatment. The aim of this study was to identify differences in fracture risk between pre-dialysis CKD patients and end-stage renal disease (ESRD) on dialysis, and to evaluate the effects of phosphate binders on fracture risk in ESRD patients. METHODS: Data from a total of 89,533 CKD patients comprising CKD diagnosis, dialysis, fracture history, and phosphate binder prescription history from 2012 to 2016 were retrieved from the Health Insurance Review and Assessment Service Database. Multivariate Cox regression analyses were performed to identify whether dialysis or phosphate binders were associated with an increased fracture risk. RESULTS: Overall, the rate of fractures in pre-dialysis CKD patients was 74 per 1,000 patient-years, while that in dialysis patients was 84 per 1,000 patient-years. The risk of fracture in ESRD patients was higher than pre-dialysis CKD patients (hazard ratio, 1.16; 95% confidence interval, 1.12-1.21; P < 0.001) after adjusting for confounding variables. In addition, the fracture risk in patients who were not taking phosphate binders was 20.0% higher compared to ESRD patients taking phosphate binders. CONCLUSION: Fractures were more prevalent in ESRD patients on dialysis than pre-dialysis CKD patients. Use of phosphate binders was associated with a lower fracture risk in ESRD patients.

Effect of reclining angle on lumbar lordosis at driving posture: A radiological evaluation.

BACKGROUND: Optimal seatback angles for automobile drivers' seats have been investigated based on comfort and back muscle activities; however, radiology supported evidences are scarce. OBJECTIVE: The aim of this study was to evaluate optimal range of the seatback reclining regarding torso angles for an automobile driver's seat to preserve lumbar lordosis. METHODS: Thirty-one healthy volunteers were recruited among five body type categories. Lateral lumbar spine X-rays were obtained for the neutral sitting posture without seatback (reference), and with reclining angles of 23∘ to 33∘ by 2∘ intervals. The Cobb angles for the L1-L4, L4-S1, and L1-S1 segments were measured. RESULTS: The Cobb angle for L4-S1 was nearest to the reference (18.74 ± 1.57∘, mean ± standard error mean) at reclining angles of 29∘ and 31∘ (14.51 ± 1.41∘ and 14.47 ± 1.43∘, respectively). The Cobb angle at L4-S1 between reclining angles of 27∘(12.02 ± 1.31∘) and 29∘ (14.51 ± 1.41∘) were significantly different (p< 0.001). Tall men showed relatively preserved lordosis angles at all reclining angles. Fat men and short women demonstrated prominent loss of lordosis with excessively kyphotic L1-L4 segment. CONCLUSIONS: Reclining angles of 29∘ to 31∘ revealed to be optimal for preserving lordosis at the L4-S1 segment. Individualized healthcare-related guideline for driver's seat adjustment setting is necessary.

Factors that Affect the Adherence to ADHD Medications during a Treatment Continuation Period in Children and Adolescents: A Nationwide Retrospective Cohort Study Using Korean Health Insurance Data from 2007 to 2011.

OBJECTIVE: Several factors, such as male gender, older age, type of insurance, comorbid conditions, and medication type, have been associated with attention-deficit/hyperactivity disorder (ADHD) medication adherence rates, but the results have been inconsistent. We analyzed data to answer several questions: 1) How old were patients who first refilled their treatment medications used primarily for ADHD, regardless of the medication type? 2) What socio-demographic factors are associated with medication adherence? 3) What medical conditions, such as medication type and comorbid diagnosis, influence adherence? METHODS: We analyzed National Health Insurance data, which comprised continuously enrolled Korean National Medical Insurance children (6-18 years) with at least 2 ADHD prescription claims (January 2008-December 2011). The persistence of use regarding the days of continuous therapy without a 30-day gap were measured continuously and dichotomously. Adherence, using a medication possession ratio (MPR), was measured dichotomously (80% cut-off). RESULTS: The cumulative incidence of index cases that initiated medication refills for ADHD treatment during the 4 year period was 0.85%. The patients who exhibited a MPR greater than 80 comprised approximately 66%. The medication type, high school age groups, physician speciality, treatment at a private clinic, and comorbid conditions were associated with medication adherence during continuous treatment using a multivariate analysis. CONCLUSION: A better understanding of ADHD treatment patterns may lead to initiatives targeted at the improvement of treatment adherence and persistence. Other factors, including the severity, family history, costs, type of comorbidities, and switching patterns, will be analyzed in future studies.

Estimation of conditions evoking fracture in finger bones under pinch loading based on finite element analysis.

A finger finite element (FE) model was created from CT images of a Japanese male in order to obtain a shape-biofidelic model. Material properties and articulation characteristics of the model were taken from the literature. To predict bone fracture and realistically represent the fracture pattern under various loading conditions, the ESI-Wilkins-Kamoulakos rupture model in PAM-CRASH (ESI Group S.A., Paris, France) was utilized in this study with parameter values of the rupture model determined by compression testing and simulation of porcine fibula. A finger pinch simulation was then conducted to validate the finger FE model. The force-displacement curve and fracture load from the pinch simulation was compared to the result of finger pinch test using cadavers. Simulation results are coincident with the test result, indicating that the finger FE model can be used in an analysis of finger bone fracture during pinch accident. With this model, several pinch simulations were conducted with different pinching object's stiffness and pinching energy. Conditions for evoking finger bone fracture under pinch loading were then estimated based on these results. This study offers a novel method to predict possible hazards of manufactured goods during the design process, thus finger injury due to pinch loading can be avoided.

Differences in Utilization Patterns among Medications in Children and Adolescents with Attention-Deficit/Hyperactivity Disorder: a 36-Month Retrospective Study Using the Korean Health Insurance Review and Assessment Claims Database.

We evaluated the differences in utilization patterns including persistence and adherence among medications in children and adolescents with attention deficit hyperactivity disorder (ADHD). The current study was performed using data from the Korean Health Insurance Review and Assessment claims database from January 1, 2009 to December 31, 2013. Our study sample consisted of 10,343 children and adolescents with ADHD who were not given their newly prescribed medication in 360 days before the initial claim in 2010. Data were followed up from the initiation of treatment with ADHD medications in 2010 to December 31, 2013. Discontinuation rates for 4 ADHD medications in our sample ranged from 97.7% for immediate-release methylphenidate to 99.4% for atomoxetine using refill gap more than 30 days and from 56.7% for immediate-release methylphenidate to 62.3% for extended-release methylphenidate using refill gap more than 60 days. In the number of discontinued, we found significant differences among medications using refill gap more than 30 days. Among 4 ADHD medications, extended-release methylphenidate and atomoxetine had more days than immediate-release methylphenidate and osmotic-controlled oral delivery system methylphenidate. In logistic regression analyses, extended-release methylphenidate, osmotic-controlled oral delivery system methylphenidate, and atomoxetine showed less discontinuation compared to immediate-release methylphenidate group when a refill gap more than 30 days was used. In logistic regression analysis of adherence, we could not find any differences among 4 medication types. We suggest that the utilization patterns should be assessed regularly in order to improve future outcomes in children and adolescents with ADHD.

Naturalistic Pharmacotherapy Compliance among Pediatric Patients with Attention Deficit/Hyperactivity Disorder: a Study Based on Three-Year Nationwide Data.

We examined short- and long-term medication compliance among youth with attention-deficit hyperactivity disorder (ADHD), using data from the National Health Insurance database in Korea. Of the 5,699,202 6-14-year-old youth in 2008, we chose those with at least 1 medical claim containing an ICD-10 code for diagnosis of ADHD (F90.0) and no prescription for ADHD within the previous 365 days. We tracked the data every 6 months between 2008 and 2011, to determine treatment compliance among newly diagnosed, medicated patients. Further, we checked every 1 month of the 6 months after treatment commencement. Treatment continuity for each patient was calculated by sequentially counting the continuous prescriptions. For measuring compliance, we applied the medication possession ratio (MPR) as 0.6, 0.7, and 0.8, and the gap method as 15- and 30-days' intervals. There were 15,133 subjects; 11,934 (78.86%) were boys. Overall 6-month treatment compliance was 59.0%, 47.3%, 39.9%, 34.1%, 28.6%, and 23.1%. Monthly drop-out rates within the first 6 months were 20.6%, 6.5%, 4.7%, 3.7%, 3.0%, and 2.5%, respectively. When applying MPR more strictly or shorter gap days, treatment compliance lessened. This is the first nationwide report on 36-month treatment compliance of the whole population of 6-14-year-olds with ADHD. We found the beginning of the treatment, especially the first month, to be a critical period in pharmacotherapy. These results also suggest the importance of setting appropriate treatment adherence standards for patients with ADHD, considering the chronic course of ADHD.

The Economic Burden of Hepatitis A, B, and C in South Korea.

The prevalence of hepatitis in South Korea is relatively high compared to that in other high-income countries. For this reason, viral hepatitis infection not only affects the population's health, but also impacts national healthcare costs. This study was performed in order to estimate the individual economic costs of the hepatitis A, B, and C viruses as well as to determine, using nationally representative data, the trends in South Korea with respect to these viruses during the 2008-2011 period. The study found that the prevalence of hepatitis A had decreased, but those of hepatitis B and C had increased overall. The mortality rate of hepatitis C was higher than that of the other two types. The mortality rate of hepatitis B had changed little, whereas that of hepatitis C had risen. The total cost of hepatitis A had decreased, from US $62.2 million to US $45.7 million, although a notable exception occurred in 2009, when the cost was US $126.6 million. Conversely, the total cost of hepatitis B had increased rapidly during the same period, from US $501.4 million to US $607.8 million. Finally, the total cost of hepatitis C had also increased from US $63.9 million to US $90.7 million. The direct costs of hepatitis A, B, and C were estimated to account for approximately 35.5%, 46.6%, and 58.0% of the total, respectively. These findings demonstrate the economic burden associated with hepatitis A, B, and C, and demonstrate the need to establish an effective prevention and management policy for future planning in South Korea.

Korea Community Health Survey Data Profiles.

In 2008, Korea Centers for Disease Control and Prevention initiated the first nationwide survey, Korea Community Health Survey (KCHS), to provide data that could be used to plan, implement, monitor, and evaluate community health promotion and disease prevention programs. This community-based cross-sectional survey has been conducted by 253 community health centers, 35 community universities, and 1500 interviewers. The KCHS standardized questionnaire was developed jointly by the Korea Centers for Disease Control and Prevention staff, a working group of health indicators standardization subcommittee, and 16 metropolitan cities and provinces with 253 regional sites. The questionnaire covers a variety of topics related to health behaviors and prevention, which is used to assess the prevalence of personal health practices and behaviors related to the leading causes of disease, including smoking, alcohol use, drinking and driving, high blood pressure control, physical activity, weight control, quality of life (European Quality of Life-5 Dimensions, European Quality of Life-Visual Analogue Scale, Korean Instrumental Activities of Daily Living ), medical service, accident, injury, etc. The KCHS was administered by trained interviewers, and the quality control of the KCHS was improved by the introduction of a computer-assisted personal interview in 2010. The KCHS data allow a direct comparison of the differences of health issues among provinces. Furthermore, the provinces can use these data for their own cost-effective health interventions to improve health promotion and disease prevention. For users and researchers throughout the world, microdata (in the form of SAS files) and analytic guidelines can be downloaded from the KCHS website (http://KCHS.cdc.go.kr/) in Korean.

The epidemiology and economic burden of Clostridium difficile infection in Korea.

The prevalence of Clostridium difficile infection and the associated burden have recently increased in many countries. While the main risk factors for C. difficile infection include old age and antibiotic use, the prevalence of this infection is increasing in low-risk groups. These trends highlight the need for research on C. difficile infection. This study pointed out the prevalence and economic burden of C. difficile infection and uses the representative national data which is primarily from the database of the Korean Health Insurance Review and Assessment Service, for 2008-2011. The annual economic cost was measured using a prevalence approach, which sums the costs incurred to treat C. difficile infection. C. difficile infection prevalence was estimated to have increased from 1.43 per 100,000 in 2008 to 5.06 per 100,000 in 2011. Moreover, mortality increased from 69 cases in 2008 to 172 in 2011. The economic cost increased concurrently, from $2.4 million in 2008 to $7.6 million, $10.5 million, and $15.8 million in 2009, 2010, and 2011, respectively. The increasing economic burden of C. difficile infection over the course of the study period emphasizes the need for intervention to minimize the burden of a preventable illness like C. difficile infection.

Nationwide rate of attention-deficit hyperactivity disorder diagnosis and pharmacotherapy in Korea in 2008-2011.

INTRODUCTION: Using the National Health Insurance database in Korea, we examined the diagnostic and treatment incidence and comorbidity of attention-deficit hyperactivity disorder (ADHD). METHODS: During 2007-2011, we chose subjects aged 6-18 years, who had at least one medical claim containing an International Classification of Diseases, 10th Revision code for diagnosis of ADHD (F90.0) with no medication use in the previous 360 days. Then, we analyzed the data for 2008-2011 to determine the mean annual incidence and prevalence of newly diagnosed and medicated patients, as well as comorbidity. RESULTS: The average annual diagnostic incidence of ADHD was 0.357% (29,310.5/8,218,252), and the incidence of medication use for ADHD was 0.248% (20,340.3/8,218,252) during 2008-2011 with no significant annual difference. The transition rate from diagnosis to medication among newly diagnosed ADHD patients was 69%. The overall prevalence rate of ADHD diagnosis and medication during 2008-2011 was 0.799% (65,702/8,218,252) and 0.610% (50,127/8,218,252), respectively. Among newly diagnosed patients with ADHD, osmotic-controlled release oral delivery system methylphenidate was the most commonly used first medication, and depression was the most common comorbid psychiatric diagnosis. DISCUSSION: This is the first report of the nationwide data on the current diagnosis and pharmacotherapy of ADHD in the whole population aged 6-18 years. We need further investigation to find the factors of low diagnostic and treatment incidence compared with high prevalence of ADHD.