Cost-Effectiveness of Sofosbuvir plus Ribavirin Therapy for Hepatitis C Virus Genotype 2 Infection in South Korea

( Wankyo Chung ),( Kyung-ah Kim ),( Eun Sun Jang ),( Moran Ki ),( Hwa Young Choi ),( Sook-hyang Jeong ) 대한간학회 2017 춘·추계 학술대회 (KASL) Vol.2017 No.1

Aims: For genotype 2 chronic hepatitis C (CHC) patients, sofosbuvir plus ribavirn (SOF+RBV) therapy showed higher response rate, better tolerability, but much higher cost than pegylated interferon plus ribavirin (PR) therapy. This study investigated the cost-effectiveness of newly introduced SOF+RBV therapy compared to the previously used PR therapy for genotype 2 CHC. Methods: A cost-utility analysis using a decision analytic Markov model compared SOF+RBV with PR and no treatment in treatment-naive genotype 2 chronic hepatitis C patients. Three cohorts of patients aged 40-49, 50-59, and 60-69 years were distributed respectively across fibrosis stages F0-F4, and simulated to progress through fibrosis stages, end-stage liver-disease complications and to death. Published data on clinical efficacy, health-related quality-of-life, costs, and transition probabilities were utilized, and sensitivity analysis was performed to assess the associated parameter uncertainty. Results: The expected quality-adjusted life years (QALYs) were higher for SOF+RBV and PR regimens compared to no treatment over a lifetime horizon. The expected costs were higher for SOF+RBV and no treatment compared to PR regimen. Compared to PR regimen, which was predicted to be dominant over no treatment, the incremental incremental cost-effectiveness ratio (ICER) was $23,677 for SOF+RBV regimen for the cohort of patients aged 40s but increased to $29,523 for those aged 50s and to $42,046 for those aged 60s. When microsimulated (10,000 trials), ICERs were $23,090, 27,947, and 41,987, respectively. Probabilistic sensitivity analysis indicated a 72.1% probability for the SOF+RBV regimen to be cost-effective at the willingness to pay of $27,205 (per-capita GDP in 2015, US$ exchange rate) for those aged 40s. Conclusions: For genotype 2 HCV patients aged forties in Korea, the sofosbuvir-based treatment could be considered a cost-effective option compared to previous treatment of pegylated interferon plus ribavirin treatment.

Costs of Liver Disease in Korea: Methodology, Data, and Evidence

Wankyo Chung(정완교) 한국간담췌외과학회 2014 한국간담췌외과학회 학술대회지 Vol.2014 No.4

대표적인 만성질환가운데 하나인 간질환은 한국인의 기대수명의 증가로 의료보건정책에서 더욱더중요해지고 있다. 간질환은 사망뿐만 아니라 많은 장애 및 손상과 관련이 있다. 2012년의 경우 간질환(K70-76)으로 6,793명(10만명당 사망률 13.5)이 사망하였으며 특히 15-64세 경제활동인구의 사망은 4,462명(10만명당 사망률 12.1)이었으며 15-64세 남성 경제활동인구의 사망은 3887명(10만명당 사망률 20.6)이었다. 따라서 간질환으로 인해 의료비 및 생산성 손실 등 많은 경제적 부담이 발생하고 있다. 이러한 간질환의 비용에 대한 연구는 자원을 효율적으로 배분하는 보건의료정책을 위해 매우 중요하다. 본 논문은 비용의 항목선정 및 양과 가치측정을 설명하고, 관련자료와 자료의 분석을 위한 통계학적 문제를 논의하며, 간질환의 비용을 측정한 기존 연구결과들을 살펴보고 개선점을 논의한다.

Electro-Mechanical Brake 제어 시스템을 위한 BLDC 모터의 벡터 제어

정완교(Wankyo Jung),이형철(Hyeongcheol Lee),전재한(Jaehan Jun),여훈(Hoon Yeo) 한국자동차공학회 2007 한국자동차공학회 춘 추계 학술대회 논문집 Vol.- No.-

This paper describes the implementation of the vector control schemes for an Electro-Mechanical Brake(EMB) with RCP device. X-by-wire implementations can lower manufacturing costs by reducing packaging problems and assembly costs. It also can provide a advantage to reduce weight of vehicle. One of these technologies is brake-by-wire system that can replace conventional hydraulic brake system An Electro-Mechanical Brake(EMB) system that is one of brake-by-wire is controlled by Vector Control Algorithm to reduce torque ripple and to improve accuracy. This paper presents experimental results that applied Vector Control Algorithm to an EMB system.

MONEY TRANSFER AND BIRTH WEIGHT: EVIDENCE FROM THE ALASKA PERMANENT FUND DIVIDEND

Chung, Wankyo,Ha, Hyungserk,Kim, Beomsoo Wiley Periodicals, Inc. 2016 ECONOMIC INQUIRY Vol.54 No.1

<P><B>Abstract</B></P><P>The positive relationship between income and health is well established. However, the direction of causality remains unclear: do economic resources influence health, or vice versa? Exploiting a new source of exogenous income variation, this study examines the impact of the Alaska Permanent Fund Dividend (APFD) on newborns' health outcomes. The results show that income has a significantly positive, but modest effect on birth weight. We find that an additional <TEX>$1,000 ($</TEX>2,331 in 2011 dollars) increases birth weight by 17.7 g and substantially decreases the likelihood of a low birth weight (a decrease of around 14% of the sample mean). Furthermore, the income effect is higher for less‐educated mothers. Based on a gestation‐weight profile in the sample, increased gestation owing to the APFD could explain a maximum of 34%–57% of the measured weight increase, although we are unable to examine all the potential mechanisms. (<I>JEL</I> I10, I18, I12)</P>

저출산 추세하에서의 출생아 건강수준 고찰

정완교(Wankyo CHUNG),이윤경 고려대학교 미래성장연구원 2022 미래성장연구 Vol.8 No.1

우리나라의 출산 수준은 정부의 지속적인 노력에도 불구하고 빠른 속도로 감소하고 있다. 본 연구는 출산과 관련된 여러 요인들을 먼저 살펴보고, 출생아의 몸무게를 출생아 건강수준에 대한 대리변수로 활용하여 출생아 건강수준과 관련된 주요 요인들을 살펴보았다. 분석 결과, 우리나라의 출산아 수는 빠른 속도로 감소하고 있는데 둘째 이상의 출산에서 그 경향이 두드러지게 나타나 “둘째아 단념 현상”이 확인되었다. 저체중 출산의 위험을 높이는 요인으로는 혼인 외 출산, 출산순서, 산모의 교육수준, 산모의 연령이 유의하였다. 따라서 출산률을 높이기 위한 정책과 더불어 건강한 출생 환경 조성과 같이 출생아 건강수준을 높이기 위한 정책도 함께 고려하여야 한다.

Self-rated health as a predictor of mortality according to cognitive impairment: findings from the Korean Longitudinal Study of Aging (2006-2016)

Goun Park,Wankyo Chung 한국역학회 2021 Epidemiology and Health Vol.43 No.-

OBJECTIVES: Self-rated health is an instrumental variable to assess the overall health status of a population. However, it remains questionable whether it is still useful for cognitively impaired individuals. Therefore, this study aims to analyze whether self-rated health by the cognitively impaired predicts mortality reliably. METHODS: This study used 7,881 community-dwelling individuals, aged 45 and above, from the Korean Longitudinal Study of Aging (2006-2016). It used the Cox proportional hazard models for analysis. Cognitive status was classified based on the Korean Mini Mental State Examination score and a stratified analysis was used to determine whether the predictability of self-rated health varies according to cognitive status. RESULTS: For cognitively intact individuals, the adjusted hazard ratios (aHR) of mortality were 2.00 (95% confidence interval [CI], 1.18 to 3.41, model 4) for those with ‘bad’ self-rated health and 2.40 (95% CI, 1.35 to 4.25, model 4) for those with ‘very bad’ self-rated heath, respectively, compared with those with ‘very good’ health. The results remain statistically significant even after adjusting for socio-demographic factors, health status, and health-related behaviors. For cognitively impaired individuals, the aHR of mortality was statistically significant for those with ‘very bad’ self-rated health, compared with those with ‘very good’ health, when socio-demographic factors were accounted for (aHR, 3.03; 95% CI, 1.11 to 8.28, model 2). CONCLUSIONS: Self-rated health by cognitively impaired individuals remains useful in predicting mortality. It appears to be a valid and reliable health indicator for the rising population with cognitive impairment, especially caused by aging population.

장기요양서비스 수요의 결정요인

정완교,Chung, Wankyo 한국개발연구원 2009 韓國 開發 硏究 Vol.31 No.1

본 논문은 65세 이상 고령인구의 수와 노인들의 건강상태 등만을 중심으로 한 기존의 연구에 더하여, 노인장기요양보험제도 제2차 시범사업의 자료를 이용한 계량분석을 통해 장기요양서비스 수요의 결정요인을 분석하였다. 분석 결과에 따르면, 우선 노인장기요양보험제도상 장기요양서비스 이용에 대한 보험 적용 대상자를 정하는 등급판정에 일상생활활동에서의 장애가 노인들이 많이 앓고 있는 고혈압, 관절염, 치매 등의 질환을 통제하고서도 통계적으로 유의한 영향을 미쳤다. 또한 노인들의 건강상태, 여성, 기초생활수급자 여부, 노인가구 형태, 노인가구의 월평균 소득 등이 장기요양서비스이용 및 이용 양태에 통계적으로 유의한 영향을 미치는 것으로 나타났다. 특히, 노인가구의 월평균 소득을 통제하고서도 장기요양서비스를 무료로 이용할 수 있는 기초생활수급 대상 노인들의 재가서비스 이용확률이 높게 나타나는데, 이는 소득과 더불어 장기요양서비스의 가격도 장기요양서비스 이용을 결정하는 중요한 요인임을 의미한다. A new public insurance for long-term care was introduced in July 2008 to provide for the rising demand for long-term care as the population is aging rapidly. The demand for long-term care is expected to rise further because more and more elderly are living alone or in households with only other elderly, such as his/her spouse, without informal care of their adult children. Even when the elderly are living together with their adult children, daughters and daughters in law, once the main informal care-givers, are not available because they choose to become economically active and work more over time. Experiences of countries such as Japan and Germany with similar public long-term care insurance scheme highlight the importance of detailed analysis on the demand for long-term care for the financial stability of the insurance scheme. Countries which had underestimated the demand for long-term care at the time of adopting the scheme went through financial instability of insurance schemes. This study analyzes the determinants of the demand for long-term care using data from the second demonstration project (April 2006~April 2007) of the long-term care insurance scheme for the elderly in Korea. Taking full advantage of detailed data on the long-term care, this paper analyzes the eligibility for the long-term care insurance scheme and its use. According to study results, even when common diseases among the elderly such as cancer, diabetes, arthritis, dementia, hypertension, etc. are controlled together with other individual and socioeconomic factors, limitations the elderly are faced with in their twelve activities of daily living significantly affect the eligibility for the Korean Long-term Care Insurance Scheme. This means that limitations in daily living activities are more critical than common diseases among the elderly are to the eligibility for the Korean Long-term Care Insurance Scheme. Bathing and toileting problems have been found to be the most important factor affecting the eligibility for the insurance scheme, followed by eating, dressing and moving around inside the house. Moreover, the choices of whether to use long-term care and which to use between home care and institutional care are found to be significantly influenced by health status and various socioeconomic factors of the elderly. In particular, those with more limitations in daily living activities and the female elderly are more likely to use long-term care and institutional care rather than home care. As for home care users, those living alone or with adult children and those with monthly household income of more than 500,000 won are more likely to use home care. Most importantly, even when the monthly household income of the elderly is controlled, the elderly recipients of the National Basic Living Security, who are not charged for long-term care, are more likely to choose home care. This implies that price as well as income is a critical factor for the decision to use long-term care. Further study on the duration of long-term care use will surely enhance the long-term care policy, when panel data is available for simultaneous analysis of the likelihood of long-term care use and its use duration.

The effect of high-dose vitamin D supplementation on insulin resistance and arterial stiffness in patients with type 2 diabetes

( Ohk Hyun Ryu ),( Wankyo Chung ),( Sung Wha Lee ),( Kyung Soon Hong ),( Moon Gi Cho ),( Hyung Joon Yoo ) 대한내과학회 2014 The Korean Journal of Internal Medicine Vol.29 No.5

Background/Aims: Recent epidemiological studies revealed a striking inverserelationship between vitamin D levels, glucose intolerance/insulin resistance (IR),and cardiovascular disease. However, few interventional studies have evaluatedthe effect of vitamin D supplementation on cardiovascular risk, such as IR andarterial stiffness, in diabetes. We investigated the role of vitamin D supplementationon cardiovascular risk in type 2 diabetes patients, including metabolic parameters,IR, and arterial stiffness. Methods: We enrolled patients who were taking antidiabetic medications or managedtheir diabetes using lifestyle changes. We excluded patients who were takingvitamin D or calcium supplements. We randomized participants into the vitaminD group (cholecalciferol 2,000 IU/day + calcium 200 mg/day, n = 40) or the placebogroup (calcium 200 mg/day, n = 41). We compared their IR (homeostasis model ofassessment [HOMA]-IR) and arterial stiffness (brachial-ankle pulse wave velocityand radial augmentation index) before and after 24 weeks of intervention. Results: The baseline characteristics of the two groups were similar. A total of 62participants (placebo, 30; vitamin D, 32) completed the study protocol. At the endof the study period, the 25-hydroxyvitamin D [25(OH)D] levels were significantlyhigher in the vitamin D group than in the placebo group (35.4 ± 8.5 ng/mL vs. 18.4± 7.3 ng/mL, p < 0.001). There was no difference in HOMA-IR or changes in arterialstiffness (placebo, 21, vitamin D, 24) between the groups. Conclusions: Our data suggest that high-dose vitamin D supplementation mightbe effective in terms of elevating 25(OH)D levels. However, we identified no beneficialeffects on cardiovascular risk in type 2 diabetes, including IR and arterialstiffness.

CAT(Computer Aided Testing)를 적용한 변속기 소음 예측기술 개발

김석산(Seoksan Kim),박완교(Wankyo Park) 한국자동차공학회 2007 한국자동차공학회 춘 추계 학술대회 논문집 Vol.2007 No.11

Cost-Effectiveness of Screening for Hepatitis C in Korean General Population

( Kyung-ah Kim ),( Wankyo Chung ),( Hwa Young Choi ),( Eun Sun Jang ),( Moran Ki ),( Sook-hyang Jeong ) 대한간학회 2017 춘·추계 학술대회 (KASL) Vol.2017 No.1

Aims: In the era of direct-acting antivirals which are highly efficacious and more widely applicable, screening and treating chronic hepatitis C virus (HCV) infection in general population would be a ponderable option. We aimed to evaluate the cost-effectiveness of HCV screening in the targeted Korean general population. Methods: We developed a Markov model simulating the natural history of chronic HCV infection using the data from surveillance data, published literature, and other secondary sources to assess the cost-effectiveness of HCV screening in Korean general population aged 40-65 years. One-time HCV screening was assumed to be performed as a part of national health screening program over two years. Treatment would be done with DAA over 3 years. The rates of screening, referral, treatment, and annual HCV detection without screening were assumed at a 0.761, 0.70, 0.681 and 0.008, respectively in a base scenario. Costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICER) and liver-related deaths were analyzed from a lifetime, payer’s perspective and sensitivity analysis was performed to assess the associated parameter uncertainty. Results: Screening was associated with QALY increase of 0.0017 and cost increase of $12.19 per a screened person, which translated to an ICER of $7116 per QALY gained, compared with no screening. ICER according to age groups was $7,719 in the cohort aged 40-49, $6,853 in the cohort aged 50-59, and $6,851 in the cohort aged 60-65 respectively. Thirty-two deaths related to chronic HCV infection, 24 hepatocellular carcinoma and 15 decompensated cirrhosis per 100,000 screened persons could be prevented. Sensitivity analyses revealed ICER ranged from $5,037 to $10,006 and increasing rates of screening, referral and treatment decreased ICER. Conclusions: One-time HCV screening in Korean general population aged 40-65 years would be cost-effective, and significantly reduce HCV-related morbidity and mortality compared with no screening.