Conducting a national burden of disease study in South Korea: from past to present

South Korea has been measuring its own burden of disease since the early 2000s and has developed a methodology for its calculation. Since 2012, South Korea has been carrying out disease burden research through the Research and Development Project, supported by the Ministry of Health and Welfare. Because the Korean health insurance system covers the entire population of the country, the Korean National Burden of Disease (KNBD) study is based on individual claims data. Disease prevalence, incidence, and mortality rates, which are the epidemiologic indicators used to calculate burden of disease, are based on actual data, and the incidence-based approach is used for Years Lived with disability (YLD), Years of Life Lost (YLL), and Disability Adjusted Life Year (DALY). The KNBD study is conducted for 260 diseases and injuries and subdivided into sub-national levels. Disability weights (DW) are calculated to reflect the sociocultural characteristics of a disease. For cause-specific DWs, we conducted a self-administered web-based survey for medical doctors and students. Using a ranking method, we calculated cause-specific DWs. For this reason, KNBD study results cannot be directly compared with GBD results.

The major findings of the KNBD study are as follows. In Korea, the DALY rate (per 100,000 people) steadily increased for all income levels. The higher the income, the lower the burden of disease; low-income people had a higher burden of disease than high-income people. However, thyroid cancer, refraction and accommodation disorders had a high burden of disease in the high-income group. Growth in the YLD rate was faster than in the YLL rate. In 2016 the leading causes of disease burden were diabetes mellitus, low back pain, and chronic obstructive pulmonary disease.

We will present South Korea's disease burden calculation methodology and its results and share the efforts to calculate disease burden in other countries.

Higher serum uric acid as a protective factor against incident osteoporotic fractures in Korean men: a longitudinal study using the National Claim Registry

In this large longitudinal study of 16,078 Korean men aged 50 years or older, we observed that baseline elevation of serum uric acid level significantly associated with a lower risk of incident fractures at osteoporosis-related sites during an average follow-up period of 3 years.

INTRODUCTION

Male osteoporosis and related fractures are becoming recognized as important public health concerns. Oxidative stress has detrimental effects on bone metabolism, and serum uric acid (UA) is known to be a strong endogenous antioxidant. In the present study, we performed a large longitudinal study with an average follow-up period of 3 years to clarify the role of UA on the risk of incident osteoporotic fractures (OFs).

METHODS

A total of 16,078 Korean men aged 50 years or older who had undergone comprehensive routine health examinations were enrolled. Incident fractures at osteoporosis-related sites (e.g., hip, spine, distal radius, and proximal humerus) that occurred after the baseline examinations were identified from the nationwide claims database of the Health Insurance Review and Assessment Service of Korea by using selected International Classification of Diseases, 10th revision codes.

RESULTS

In total, 158 (1.0 %) men developed incident OFs. The event rate was 33.1 per 10,000 person-years. Subjects without incident OFs had 6.0 % higher serum UA levels than subjects with OFs (P = 0.001). Multivariable-adjusted Cox proportional hazard analyses adjusted for age, body mass index, glomerular filtration rate, lifestyle factors, medical and drug histories, and the presence of baseline radiological vertebral fractures revealed that the hazard ratio per standard deviation increase of baseline UA levels for the development of incident OFs was 0.829 (95 % CI = 0.695-0.989, P = 0.038).

CONCLUSIONS

These data provide the epidemiological evidence that serum UA may act as a protective factor against the development of incident OFs in Korean men.

Measuring the burden of chronic diseases in Korea in 2007

OBJECTIVES

This study was performed to measure the burden of disease from premature death and disability for chronic diseases in Korea in 2007.

STUDY DESIGN

Chronic diseases were defined using the WHO definitions. Disability-adjusted life years (DALY) were used to analyse insurance claim data.

METHODS

This was a population-based study and included the total population of Korea. DALYs were used to analyse insurance claim data. Years of life lost (YLL) and years lost to disability (YLD) were measured in terms of incidence rate and number of deaths. DALYs were aggregated to YLL and YLD. To ensure code validity, only patients who had visited a tertiary hospital or a clinic three or more times for the same disease were included.

RESULTS

Cerebrovascular disease was the leading contributor to the chronic disease burden, with a value of 907.4, followed by diabetes mellitus (899), ischaemic heart disease (710), cirrhosis of the liver (616.5), chronic obstructive pulmonary disease (512.9), asthma (503.1), hypertensive heart disease (407.5), stomach cancer (356) and peptic ulcer disease (292.5). As these results demonstrate, the highest ranked diseases were cardio-cerebrovascular or related diseases, as well as the fact that hypertension, diabetes mellitus and related complications, which are associated diseases, have became increasingly severe problems. And the rural areas have a higher burden of disease than metropolitan cities. According to difference in social status, Medicaid 2 group has more burden of disease than other groups.

CONCLUSIONS

It has been possible to present evidence regarding the burden of diseases and the relatively high risk of cardio-cerebrovascular disease. If the various types of cancer were combined and then the calculating tool applied, the burden would likely be greater than that of cardio-cerebrovascular disease. However, based on DALY, ischaemic heart disease demonstrated a remarkable increase compared to the rate in the previous study based on 2002 data. Underprivileged people in particular have been struggling - with chronic diseases.

Age- and weight-adjusted warfarin initiation nomogram for ischaemic stroke patients

OBJECTIVES

Specific guidelines for initial dosing of warfarin in ischaemic stroke patients have not been developed. Therefore, we have developed an age- and weight-adjusted warfarin initiation nomogram (AW-WIN) for ischaemic stroke patients and then evaluated the efficacy and safety of AW-WIN compared with physician-determined warfarin dosing (PDWD).

METHODS

The age- and weight-adjusted warfarin initiation nomogram was administered to 104 acute ischaemic stroke patients between January 2008 and February 2009. A historical control group (PDWD) of 96 patients was selected from comparable patients who were discharged with warfarin during the previous year. Time-to-therapeutic international normalized ratios (INRs) and the incidence of excessive anticoagulation were compared in the AW-WIN and PDWD groups.

RESULTS

The general characteristics, risk factors, and stroke mechanism of the AW-WIN and PDWD groups did not differ significantly. The mean time to INR ≥ 2.0 was significantly shorter in the AW-WIN than in the PDWD group (4.9 ± 0.7 vs. 6.2 ± 0.8 days, P = 0.0008). After adjustment for potential confounding variables, the AW-WIN group reached target INR faster than the PDWD group (hazard ratio, 1.76; 95% confidence interval, 1.26-2.45; P = 0.001). The time-to-therapeutic INR ≥1.7 was shorter (P = 0.0002), the proportion of patients with therapeutic INR (2-3) at 5 days was higher (P = 0.002), and the rate of excessive anticoagulation of ≥3.5 INR during hospitalization was lower (P = 0.024) in the AW-WIN than in the PDWD group.

CONCLUSIONS

AW-WIN reduces the time to target INR and the risk of excessive anticoagulation. AW-WIN may be an efficient and safe method of anticoagulation during the acute phase of ischaemic stroke.