Risk factors associated with the discordance in kidney function decline rate in identical twins.

BACKGROUND: The rate of kidney function decline is different for each individual regardless of any difference in the medical histories. This study set out to identify the risk factors for high discordance in kidney function decline in an identical twin cohort. METHODS: This study included 333 identical twins from the Korean Genome and Epidemiology Study who were categorized into two groups according to the estimated glomerular filtration rate (eGFR) decline: the slow and rapid progressor groups. The mean differences of variables were compared between the two groups. We calculated the difference in the annual eGFR change between twins and analyzed the risk factors associated with high discordance in twins who had > 5 mL/min/1.73 m2 /yr of the intra-twin difference in the annual eGFR decline. Identical twins with diabetes and baseline eGFR < 60 mL/min/1.73 m2 were excluded. RESULTS: The high discordance twins showed significant differences in body mass index; waist-to-hip ratio; total body fat percentage; and levels of blood hemoglobin, serum fasting glucose, albumin, triglyceride, and uric acid; however, there were no differences in low discordance twins. Multivariable logistic regression showed that blood hemoglobin level is the only significant factor associated with high discordance of eGFR decline in twins. CONCLUSIONS: Blood hemoglobin level may play a role in the individual differences in kidney function decline.

Waist-hip ratio measured by bioelectrical impedance analysis as a valuable predictor of chronic kidney disease development.

Obesity is a major health problem worldwide and is associated with chronic kidney disease (CKD). Body mass index (BMI) is a common method of diagnosing obesity, but there are concerns about its accuracy and ability to measure body composition. This study evaluated the risk of CKD development in a middle-aged population in association with various body composition metrics. From a prospective cohort of 10,030 middle-aged adults, we enrolled 6727 for whom baseline and follow-up data were available. We collected data pertaining to participants' BMI, manually measured waist-hip ratio (WHR), and various measurements of bioelectrical impedance analysis (BIA), including total body fat content, muscle content, and calculated WHR, and classified the participants into quintiles accordingly. CKD was defined as an estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m2 in follow-up laboratory tests. While an increase in BMI, WHR, and total body fat were associated with an elevated risk of CKD, an increase in total body muscle decreased the risk. Among the body composition metrics, WHR measured by BIA had the highest predictive value for CKD (C-statistics: 0.615). In addition, participants who were "healthy overweight, (defined as low WHR but high BMI), exhibited a 62% lower risk of developing CKD compared to those with "normal-weight obesity," (defined as high WHR despite a normal BMI). In conclusion, we suggest that central obesity measured by BIA is a more accurate indicator than BMI for predicting the development of CKD.

Changes in Mortality According to Creatinine/Cystatin C Ratio in Chronic Kidney Disease and Non-chronic Kidney Disease Patients.

Background: Serum creatinine and cystatin C are not only good indicators of renal function but have also been confirmed to be related to disease prognosis and mortality in various diseases via creatinine/cystatin C ratio (CCR). However, although they are biomarkers of renal function, there is no study regarding renal impairment as a confounding variable in the relationship between CCR and all-cause mortality. Methods: Patients who had simultaneous measurements of serum creatinine and cystatin C between 2003 and 2020 were enrolled. The patients with chronic kidney disease (CKD) were defined as having an estimated glomerular filtration rate (eGFR) CKD-EPI Cr-Cystatin C < 60 ml/min/1.73 m2. CCR was calculated by dividing the serum creatinine level by the cystatin C level measured on the same day. The main outcome assessed was all-cause mortality according to CCR in CKD or non-CKD groups. Results: Among the 8,680 patients in whom creatinine and cystatin C levels were measured simultaneously, 4,301 were included in the CKD group, and 4,379 were included in the non-CKD group, respectively. CCR was 1.4 ± 0.6 in total participants. The non-CKD group showed higher mean CCR, (1.5 ± 0.7 vs. 1.3 ± 0.5) as well as a wider distribution of CCR (p < 0.001) when compared to the CKD group. In non-CKD group, 1st, 4th and 5th quintiles of CCR significantly increased the all-cause mortality risk compared to 2nd quintile of CCR, suggesting U-shaped mortality risk according to CCR in non-CKD. On the other hand, in CKD group, the risk of all-cause mortality linearly increased and 5th quintile of CCR showed 1.82 times risk of mortality compared to 2nd quintile of CCR. In the subgroup analysis of mortality by age and sex, the mortality difference according to CCR were diminished in old age and female sex subgroups. Conclusion: We discovered a U-shaped relationship between mortality and CCR levels in normal renal function, and an increased risk of mortality in CKD with elevated CCR.

Private health insurance in South Korea: an international comparison.

OBJECTIVES: The goal of this study is to present the historical and policy background of the expansion of private health insurance in South Korea in the context of the National Health Insurance (NHI) system, and to provide empirical evidence on whether the increased role of private health insurance may counterbalance government financing, social security contributions, out-of-pocket payments, and help stabilize total health care spending. METHODS: Using OECD Health Data 2011, we used a fixed effects model estimation. In this model, we allow error terms to be serially correlated over time in order to capture the association of private health insurance financing with three other components of health care financing and total health care spending. RESULTS: The descriptive observation of the South Korean health care financing shows that social security contributions are relatively limited in South Korea, implying that high out-of-pocket payments may be alleviated through the enhancement of NHI benefit coverage and an increase in social security contributions. Estimation results confirm that private health insurance financing is unlikely to reduce government spending on health care and social security contributions. We find evidence that out-of-pocket payments may be offset by private health insurance financing, but to a limited degree. Private health insurance financing is found to have a statistically significant positive association with total spending on health care. This indicates that the duplicated coverage effect on service demand may cancel out the potential efficiency gain from market initiatives driven by the active involvement of private health insurance. CONCLUSIONS: This study finds little evidence for the benefit of private insurance initiatives in coping with the fiscal challenges of the South Korean NHI program. Further studies on the managerial interplay among public and private insurers and on behavioral responses of providers and patients to a given structure of private-public financing are warranted to formulate the adequate balance between private health insurance and publicly funded universal coverage.

Quality of care and role of health insurance among non-elderly women with disabilities.

OBJECTIVES: We examined differences in the quality of health care provided by usual source of care providers between women with and without disabilities in the United States. The role of health insurance in ensuring equitable quality of care for women with disabilities was investigated. METHODS: A national sample of 12,199 women aged 18-64 was drawn from the 2002 Medical Expenditure Panel Survey. Descriptive and multivariate analyses were performed to investigate the interactive associations of disability and insurance coverage with accessibility, satisfaction and adequacy of care among women. RESULTS: Compared with women without disabilities, women with disabilities were more likely to experience lower quality of care in terms of accessibility of care, satisfaction with care, and adequate receipt of care. This diminished quality of care for women with disabilities was alleviated, but only to a limited extent, by health insurance coverage. A significant difference remained in the quality of care between the 2 insured subgroups. CONCLUSIONS: Having health insurance was strongly associated with improved access to care and reduced unmet or delayed care among women with disabilities in the United States. In addition to an expansion of public insurance program eligibility, the quality of care provided under the public insurance system needs to be ensured to maximize appropriate and timely care for women with disabilities.

Performance of universal health insurance: lessons from South Korea.

The aim of this study was to assess the maturity of the South Korean healthcare system in comparison with those of the 30 countries of the Organization for Economic Co-operation and Development (OECD) and to provide a foundation to evaluate the performance of the South Korean healthcare system. Using OECD Health Data 2005, we evaluated the performance of the healthcare system of the 30 industrialized countries. The evaluation focused on three dimensions that have remained central to healthcare debates internationally for years: access, cost and outcomes. Although South Korea has successfully implemented its universal health insurance scheme in a very short period of time and possesses highly advanced medical technologies, we found that South Koreans incurred more out-of-pocket expenditures on healthcare. Health outcomes were of relatively low quality compared with those of other OECD countries, but compared relatively well with the four countries (Greece, New Zealand, Portugal and Spain) with similar per capita gross domestic product (GDP).

Performance of universal health insurance: lessons from South Korea.

The aim of this study was to assess the maturity of the South Korean healthcare system in comparison with those of the 30 countries of the Organization for Economic Co-operation and Development (OECD) and to provide a foundation to evaluate the performance of the South Korean healthcare system. Using OECD Health Data 2005, we evaluated the performance of the healthcare system of the 30 industrialized countries. The evaluation focused on three dimensions that have remained central to healthcare debates internationally for years: access, cost and outcomes. Although South Korea has successfully implemented its universal health insurance scheme in a very short period of time and possesses highly advanced medical technologies, we found that South Koreans incurred more out-of-pocket expenditures on healthcare. Health outcomes were of relatively low quality compared with those of other OECD countries, but compared relatively well with the four countries (Greece, New Zealand, Portugal and Spain) with similar per capita gross domestic product (GDP).

Health care utilization among Medicare-Medicaid dual eligibles: a count data analysis.

BACKGROUND: Medicare-Medicaid dual eligibles are the beneficiaries of both Medicare and Medicaid. Dual eligibles satisfy the eligibility conditions for Medicare benefit. Dual eligibles also qualify for Medicaid because they are aged, blind, or disabled and meet the income and asset requirements for receiving Supplement Security Income (SSI) assistance. The objective of this study is to explore the relationship between dual eligibility and health care utilization among Medicare beneficiaries. METHODS: The household component of the nationally representative Medical Expenditure Panel Survey (MEPS) 1996-2000 is used for the analysis. Total 8,262 Medicare beneficiaries are selected from the MEPS data. The Medicare beneficiary sample includes individuals who are covered by Medicare and do not have private health insurance during a given year. Zero-inflated negative binomial (ZINB) regression model is used to analyse the count data regarding health care utilization: office-based physician visits, hospital inpatient nights, agency-sponsored home health provider days, and total dental visits. RESULTS: Dual eligibility is positively correlated with the likelihood of using hospital inpatient care and agency-sponsored home health services and the frequency of agency-sponsored home health days. Frequency of dental visits is inversely associated with dual eligibility. With respect to racial differences, dually eligible Afro-Americans use more office-based physician and dental services than white duals. Asian duals use more home health services than white duals at the 5% statistical significance level. The dual eligibility programs seem particularly beneficial to Afro-American duals. CONCLUSION: Dual eligibility has varied impact on health care utilization across service types. More utilization of home healthcare among dual eligibles appears to be the result of delayed realization of their unmet healthcare needs under the traditional Medicare-only program rather than the result of overutilization in response to the expanded benefits of the dual eligibility program. The dual eligibility program is particularly beneficial to Asian and Afro-American duals in association with the provision of home healthcare and dental benefits.

Racial differences in health care use among medicare only and dual eligibles.

It has been an important financial issue in the U.S. Medicare expenditures that health care expenses of Medicaid-Medicare dual eligibles (MMDE) are much higher than those of Medicare only beneficiaries (MOB). This paper compares health care use and health status of MMDEs and MOBs who are either Afro-American or white recipients. Using total health care use information from the Medical Expenditure Panel Survey (MEPS) 2000, we find that the proportion of dual eligibles with chronic health conditions is higher by 4% than that of the Medicare only beneficiaries and that dual eligibles make more frequent uses of various health care services. The number of office-based physician visits and outpatient physician visits are higher for Afro-American dual eligibles than white dual eligibles. This finding seems to be contributed to by relatively high medical needs among dual eligibles. Higher utilization of agency-related home health services among Afro-American dual eligibles than among white dual eligibles is considered as a consequence of different ethnicity-specific responses to insurance coverage.

The effect of the Americans with Disabilities Act on economic well-being of men with disabilities.

This paper estimates the effect of the Americans with Disabilities Act (ADA) on the economic well-being of working-age (20-62) men with disabilities by fitting a fixed-effects model to the U.S. Survey of Income and Program Participation (SIPP) panel data. This paper constructs a new and alternative measure of disability utilizing rich information on limitations to functional activities (FA), activities of daily living (ADL), and instrumental activities of daily living (IADL). The new objective measure of disability identifies a larger group of people as being disabled than conventional self-reported measure. Probability of employment for disabled men fell 5.8% compared to nondisabled men significantly at the 5% level. Log-real-wages of men with disabilities fell 5.3% relative to men without disabilities significantly at the 10% level.