Assessing blood sugar measures for predicting new-onset diabetes and cardiovascular disease in community-dwelling adults

PURPOSE

Diabetes mellitus (DM) is a global health concern linked to various complications, including cardiovascular disease (CVD). However, long-term follow-up studies on the risk of DM and CVD using different blood glucose assessment methods in the general Korean population are lacking. This study aimed to assess the predictive abilities of fasting plasma glucose (FPG), 2-h oral glucose tolerance test (OGTT), and glycosylated hemoglobin (HbA1c) for new-onset DM and high CVD risk in a middle-aged and older Korean population.

METHODS

This study used data from the Korean Genome and Epidemiology Study, a population-based prospective cohort. Blood sugar measures (FPG, OGTT, and HbA1c) were examined. The primary endpoint was the development of new-onset DM, and CVD risk was evaluated using the Framingham risk score. The predictive abilities for new-onset DM based on glycemic values were evaluated using Harrell's Concordance index and 95% confidence intervals.

RESULTS

Among the 10,030 participants, data of 6813 participants without DM at baseline were analyzed. The study revealed that OGTT outperformed FPG and HbA1c in predicting new-onset DM. The combination of FPG and HbA1c did not significantly enhance predictions for DM compared with OGTT alone. OGTT also outperformed FPG and HbA1c in predicting high CVD risk, and this difference remained significant even after adjusting for additional confounders.

CONCLUSION

OGTT has superior predictive capabilities in identifying new-onset DM and high CVD risk in the Korean population. This suggests that relying solely on individual blood sugar measures may be insufficient for assessing DM and CVD risks.

Association between physical activity and health-related quality of life in middle-aged and elderly individuals with musculoskeletal disorders: Findings from a national cross-sectional study in Korea

PURPOSE

This study aimed to identify the association between physical activity and health-related quality of life (HRQoL) in middle-aged and elderly individuals with musculoskeletal disorders.

METHODS

This study used data from the 2016-2020 Korea National Health and Nutrition Examination Survey (KNHANES). We included only those over 40 years of age diagnosed with one or more of the following: osteoarthritis, rheumatism, and osteoporosis. In total, 4,731 participants (783 men and 3,948 women) were included as the study population. Multiple logistic regression analysis was performed to examine the association between physical activity and HRQoL.

RESULTS

In the case of middle-aged and elderly individuals with musculoskeletal disorders, the likelihood of HRQoL worsening was significantly lower for those who regularly engaged in physical activity compared with that of those who did not engage in physical activity at all (men: OR 0.58, 95% CI 0.37-0.90; women: OR 0.64, 95% CI 0.53-0.79). Stratified analysis by the type and intensity of physical activity revealed that the possibility of poor HRQoL was lowest when leisure-related moderate-intensity physical activities were performed (men: OR 0.44, 95% CI 0.22-0.89; Women: OR 0.50, 95% CI 0.36-0.69).

CONCLUSIONS

Our findings suggest that engaging in regular physical activity contributes to preventing exacerbation of HRQoL, even if the individual suffers from musculoskeletal disorders. It is necessary to provide an appropriate type and intensity of physical activity in consideration of the patients' pain and severity.

Association between having a meal together with family and smoking: a cross-sectional nationwide survey

BACKGROUND

Smoking is a major risk factor that significantly affects public health. Although the South Korean government spends significant money on smoking cessation services, the smoking rate remains stagnant. Families influence health-conscious decisions, and family meals can positively affect smoking suppression and health behaviors. Therefore, this study investigated whether family meals are correlated with adults' smoking behaviors.

METHODS

This study used data from the 2019-2021 Korean National Health and Nutrition Examination Survey. Having a meal together with family was defined as "yes" for those who have at least one meal with their family each day and "no" for those who do not. Current smoking status was classified as having smoked at least 5 packs of cigarettes (100 cigarettes) in one's lifetime and having used either conventional cigarettes or e-cigarettes in the last 30 days. Multiple logistic regression analyses were used to examine the association between eating together, smoking, and weight application.

RESULTS

When comparing the group that ate with their family compared to the group that did not, the odds ratio for current smoking status was 1.27 (95% confidence interval [CI]: 1.05-1.54) for male participants and 1.90 (95% CI: 1.33-2.71) for female participants. This showed a dose-dependent effect according to the frequency of family meals. Those who smoked conventional cigarettes had a strong association (men: OR 1.28, 95% CI 1.00-1.67; women: OR 2.22, 95% CI 1.42-3.46). However, those who only vaped e-cigarettes or used both conventional cigarettes and e-cigarettes had no statistically significant correlations.

CONCLUSION

This study provides evidence suggesting that eating meals as a family is related to smoking behavior and can positively affect smoking cessation intentions in adults. Consequently, a smoking cessation program can be developed that uses social support, such as encouraging family meals.

Combination therapy with moderate-intensity atorvastatin and ezetimibe versus high-intensity atorvastatin monotherapy in patients treated with percutaneous coronary intervention in practice: assessing RACING generalizability

AIMS

Using rosuvastatin, the RACING (randomized comparison of efficacy and safety of lipid-lowering with statin monotherapy versus statin/ezetimibe combination for high-risk cardiovascular diseases) trial showed the beneficial effects of combining moderate-intensity statin with ezetimibe compared with high-intensity statin monotherapy in patients with atherosclerotic cardiovascular disease. This study investigated whether the beneficial effects of combination lipid-lowering therapy extend to patients treated with atorvastatin, not rosuvastatin, in daily clinical practice.

METHODS AND RESULTS

Using stabilized inverse probability of treatment weighting, a total of 31 993 patients who were prescribed atorvastatin after drug-eluting stent (DES) implantation were identified from a nationwide cohort database: 6 215 patients with atorvastatin 20 mg plus ezetimibe 10 mg (combination lipid-lowering therapy) and 25 778 patients with atorvastatin 40-80 mg monotherapy. The primary endpoint was the 3-year composite of cardiovascular death, myocardial infarction, coronary artery revascularization, hospitalization for heart failure treatment, or non-fatal stroke in accordance with the RACING trial design. Combination lipid-lowering therapy was associated with a lower incidence of the primary endpoint (12.9% vs. 15.1% in high-intensity atorvastatin monotherapy; hazard ratio [HR] 0.81, 95% confidence interval [CI] 0.74-0.88, p < 0.001). Compared with high-intensity atorvastatin monotherapy, combination lipid-lowering therapy was also significantly associated with lower rates of statin discontinuation (10.0% vs. 8.4%, HR 0.81, 95% CI 0.73-0.90, p < 0.001) and new-onset diabetes requiring medication (8.8% vs. 7.0%, HR 0.80, 95% CI 0.70-0.92, p = 0.002).

CONCLUSIONS

In clinical practice, a combined lipid-lowering approach utilizing ezetimibe and moderate-intensity atorvastatin was correlated with favorable clinical outcomes, drug compliance, and a reduced incidence of new-onset diabetes requiring medications in patients treated with DES implantation. Trial registration: ClinicalTrial.gov (NCT04715594).

Motivating factors of compliance to government's COVID-19 preventive guidelines: An investigation using discrete choice model

BACKGROUND

The spread of coronavirus disease 2019 (COVID-19) has resulted in a worldwide pandemic. We aimed to identify the factors that motivate public compliance with the government's COVID-19 preventive recommendations.

METHODS

Focus group interviews were conducted to identify influencing factors. The relative importance of each factor was investigated through a survey, based on a discrete choice model, from February to June, 2021 in South Korea.

RESULTS

"Severity of COVID-19 symptoms" (relative importance [magnitude of attribute coefficients]: 28.40%) and "risk of infection" (27.50%) were the most influential health-related factors, followed by social consequences of infection, including "cessation of social activities due to self-quarantine" (19.77%), "risk of personal information being disclosed when infected and social criticism on the infected person" (15.78%), and "risk of spreading infection" (8.55%). Respondents behaved differently based on their socioeconomic characteristics and COVID-19 experience.

DISCUSSION

The perceived severity of symptoms was a strong motivator among fragile individuals, such as women and older adults. "Cessation of social activities" was the most influential factor for those infected with COVID-19, while "risk of infection" was for those whose acquaintances were infected.

CONCLUSIONS

The provision of information regarding COVID-19 to the public must be tailored based on an understanding of behavioral differences.

Combination Lipid-Lowering Therapy in Patients Undergoing Percutaneous Coronary Intervention

BACKGROUND

The RACING (randomized comparison of efficacy and safety of lipid-lowering with statin monotherapy versus statin/ezetimibe combination for high-risk cardiovascular diseases) trial examined the effects of combination therapy with moderate-intensity statin and ezetimibe in patients with atherosclerotic cardiovascular disease compared with high-intensity statin monotherapy.

OBJECTIVES

This observational study was conducted to evaluate the impact of 2 treatment strategies used in the RACING trial in clinical practice.

METHODS

After stabilized inverse probability of treatment weighting, a total of 72,050 patients who were prescribed rosuvastatin after drug-eluting stent implantation were identified from a nationwide cohort database: 10,794 patients with rosuvastatin 10 mg plus ezetimibe 10 mg (combination lipid-lowering therapy) and 61,256 patients with rosuvastatin 20 mg monotherapy. The primary endpoint was the 3-year composite event of cardiovascular death, myocardial infarction, coronary artery revascularization, hospitalization for heart failure treatment, or nonfatal stroke in accordance with the RACING trial.

RESULTS

Combination lipid-lowering therapy was associated with a lower occurrence of the primary endpoint (11.6% vs 15.2% for those with high-intensity statin monotherapy; HR: 0.75; 95% CI: 0.70-0.79; P < 0.001). Compared with high-intensity statin monotherapy, combination lipid-lowering therapy was associated with fewer discontinuations of statin (6.5% vs 7.6%; HR: 0.85; 95% CI: 0.78-0.94: P < 0.001) and a lower occurrence of new-onset diabetes requiring medication (7.7% vs 9.6%; HR: 0.80; 95% CI: 0.72-0.88; P < 0.001).

CONCLUSIONS

In clinical practice, combination lipid-lowering therapy with ezetimibe and moderate-intensity statin was associated with favorable clinical outcomes and drug compliance in patients treated with drug-eluting stent implantation. (CONNECT DES Registry; NCT04715594).

The impact of assisted reproductive technology treatment coverage on marriage, pregnancy, and childbirth in women of childbearing age: an interrupted time-series analysis

BACKGROUND

Korea is encountering major challenges related to its declining birth rate and aging population. Various policies have been introduced to prevent further population decrease and boost the birth rate, but their effectiveness has not been verified. Therefore, this study examined the effects of assisted reproductive technology (ART) insurance coverage on marriage, pregnancy, and childbirth in women of childbearing age.

METHODS

All information on marriage, pregnancy, childbirth of women of childbearing age was obtained from Statistics Korea and Korean National Health Insurance Service database. During a total follow-up period of 54 months (July 2015 to December 2019), an average of 12,524,214 women of childbearing age per month, and 29,701 live births per month were included in the analysis. An interrupted time series with segmented regression was performed to analyze the time trend and changes in outcomes.

RESULTS

The implementation of ART coverage policies had no significant impact on marriage or pregnancy rates. However, it did affect multiple pregnancy and multiple birth rates, which increased by 1.0% (Exp(β3) = 1.010, P-value = 0.0001) and 1.4% (Exp(β3) = 1.014, P-value = < 0.0001), respectively, compared to the pre-intervention period. Although the effect of covering ART treatment on total birth rates were not confirmed, a slightly slower decline was observed after the intervention (Exp(β1) = 0.993, P-value = < 0.0001, Exp(β1 + β3) = 0.996 P-value = 0.012).

CONCLUSION

This study identified the effects of ART health insurance coverage policy on the rates of multiple pregnancies and births. After the policy implementation, the downward trend in the total birth rate reduced slightly. Our findings suggest that interventions to support infertile couples should be expanded to solve the problem of low fertility rates. To address the intricate problems related to low birth rates, the Korean government introduced a policy that provides financial support and health insurance coverage for assisted reproductive technology (ART) treatment for infertile couples. As a result of evaluating the effectiveness of the ART coverage policy, it led to higher rates of pregnancies and births. In addition, although the total birth rate has been continuously decreasing over time, the decline may have been slowed down slightly by this policy.

Effect of regional medical disparities on complications in patients with hypertension: Cox's proportional hazard models

Objective

Complications associated with hypertension can be alleviated by providing necessary medical services. However, there may be disparities in their provision depending on regional differences. Thus, this study aimed to examine the effects of regional healthcare disparities on complications in patients with hypertension in South Korea.

Methods

Data from the National Health Insurance Service National Sample Cohort (2004-2019) were analyzed. The position value for the relative composite index was used to identify medically vulnerable regions. The diagnosis of hypertension within the region was also considered. The risk of complications associated with hypertension included cardiovascular, cerebrovascular, and kidney diseases. Cox proportional hazards models were used for statistical analysis.

Results

A total of 246,490 patients were included in this study. Patients who lived in medically vulnerable regions and were diagnosed outside their residential area had a higher risk of complications than those living in non-vulnerable regions and were diagnosed outside the residential area (hazard ratio: 1.156, 95% confidence interval: 1.119-1.195).

Conclusion

Patients living in medically vulnerable regions who were diagnosed outside their residential areas were more likely to have hypertension complications regardless of the type of complication. Necessary policies should be implemented to reduce regional healthcare disparities.

Evaluation of Assisted Reproductive Technology Health Insurance Coverage for Multiple Pregnancies and Births in Korea

Importance

While various policies to support couples experiencing infertility have been introduced due to the fertility rate rapidly dropping in developed countries, few large-scale nationwide cohort studies have evaluated the outcomes of assisted reproductive technology (ART) health insurance coverage policies.

Objective

To evaluate ART health insurance coverage for multiple pregnancies and births in Korea.

Design, Setting, and Participants

This population-based cohort study used delivery cohort data from the Korean National Health Insurance Service database between July 1, 2015, and December 31, 2019. A total of 1 474 484 women were included after exclusion of those who gave birth at nonmedical institutions and those with missing data.

Exposure

Two 27-month periods were examined before and after the Korean National Health Insurance Service had begun covering ART treatment (preintervention period, July 1, 2015, to September 30, 2017; postintervention period, October 1, 2017, to December 31, 2019).

Main Outcomes and Measures

Multiple pregnancies and multiple births were identified by International Statistical Classification of Diseases and Related Health Problems, Tenth Revision diagnosis codes. Total births were defined as the total number of babies born to each pregnant woman during the follow-up period. An interrupted time series with segmented regression was conducted to analyze the time trend and its change in outcomes. Data analysis was conducted between December 2, 2022, and February 15, 2023.

Results

Of the 1 474 484 women eligible for the analysis (mean [SD] age, 33.2 [4.6] years), approximately 1.60% had multiple pregnancies and 1.10% had multiple births. After covering ART treatment, the likelihood of multiple pregnancies and multiple births was estimated to increase by 0.7% (estimate, 1.007; 95% CI, 1.004-1.011; P < .001) and 1.2% (estimate, 1.012; 95% CI, 1.007-1.016; P < .001) compared with before coverage. The probability of an increase in the number of total births per pregnant woman after the intervention was estimated to be 0.5% (estimate, 1.005; 95% CI, 1.005-1.005; P < .001). The relatively high-income class above the median income showed a decreasing trend in multiple births and total births before the intervention, but after the intervention, a significant increase was observed.

Conclusions and Relevance

This population-based cohort study found that the possibility of multiple pregnancies and births in Korea significantly increased after the implementation of an ART health insurance coverage policy. These findings suggest that the development and coverage of policies to support couples experiencing infertility may help address low fertility rates.

Regional Differences in Medical Costs of Chronic Kidney Disease in the South Korean Population: Marginalized Two-Part Model

BACKGROUND

There are regional gaps in the access to medical services for patients with chronic kidney disease (CKD), and it is necessary to reduce those gaps, including the gaps involving medical costs.

OBJECTIVE

This study aimed to analyze regional differences in the medical costs associated with CKD in the South Korean population.

METHODS

This longitudinal cohort study included participants randomly sampled from the National Health Insurance Service-National Sample Cohort of South Korea. To select those who were newly diagnosed with CKD, we excluded those who were diagnosed in 2002-2003 and 2018-2019. A total of 5903 patients with CKD were finally included. We used a marginalized two-part longitudinal model to assess total medical costs.

RESULTS

Our cohort included 4775 (59.9%) men and 3191 (40.1%) women. Of these, 971 (12.2%) and 6995 (87.8%) lived in medically vulnerable and nonvulnerable regions, respectively. The postdiagnosis costs showed a significant difference between the regions (estimate: -0.0152, 95% confidence limit: -0.0171 to -0.0133). The difference in medical expenses between the vulnerable and nonvulnerable regions showed an increase each year after the diagnosis.

CONCLUSIONS

Patients with CKD living in medically vulnerable regions are likely to have higher postdiagnostic medical expenses compared to those living in regions that are not medically vulnerable. Efforts to improve early diagnosis of CKD are needed. Relevant policies should be drafted to decrease the medical costs of patients with CKD disease living in medically deprived areas.

Prolonged dual antiplatelet therapy after drug-eluting stent implantation in patients with diabetes mellitus: A nationwide retrospective cohort study

Background

Optimal duration of dual antiplatelet therapy (DAPT) in patients with diabetes mellitus (DM) who have undergone drug-eluting stent (DES) implantation is not clearly established. This study sought to impact of DAPT duration on real-world clinical outcome in patients with or without DM.

Methods

Using a nationwide cohort database, we investigate the association between DAPT duration and clinical outcome between 1 and 3 years after percutaneous coronary intervention (PCI). Primary outcome was all-cause death. Secondary outcomes were cardiovascular death, myocardial infarction, and composite bleeding events. After weighting, 90,100 DES-treated patients were included; 29,544 patients with DM and 60,556 without DM; 31,233 patients with standard DAPT (6–12 months) and 58,867 with prolonged DAPT (12–24 months).

Results

The incidence of all-cause death was significantly lower in patients with prolonged DAPT [8.3% vs. 10.5% in those with standard DAPT, hazard ratio (HR) 0.78, 95% confidence interval (CI) 0.72–0.84] in diabetic patients and non-diabetic patients (4.5% vs. 5.0% in those with standard DAPT, HR 0.89, 95% CI 0.83–0.96). The incidence of composite bleeding events was 5.7% vs. 5.4%, respectively, (HR 1.07, 95% CI 0.96–1.18) in diabetic patients and 5.6% vs. 5.0%, respectively, in non-diabetic patients (HR 1.13, 95% CI 1.05–1.21). There was a significant interaction between the presence of DM and DAPT duration for all-cause death (p for interaction, p_int = 0.01) that further favored prolonged DAPT in diabetic patients. However, there was no significant interaction between the presence of DM and DAPT duration for composite bleeding events (p_int = 0.38).

Conclusions

This study showed that prolonged rather than standard DAPT might be clinically beneficial in diabetic patients with DES implantation.

Trial registration

ClinicalTrial.gov (NCT04715594).

Deep Learning Model for Predicting Intradialytic Hypotension Without Privacy Infringement: A Retrospective Two-Center Study

Objective

Previously developed Intradialytic hypotension (IDH) prediction models utilize clinical variables with potential privacy protection issues. We developed an IDH prediction model using minimal variables, without the risk of privacy infringement.

Methods

Unidentifiable data from 63,640 hemodialysis sessions (26,746 of 79 patients for internal validation, 36,894 of 255 patients for external validation) from two Korean hospital hemodialysis databases were finally analyzed, using three IDH definitions: (1) systolic blood pressure (SBP) nadir <90 mmHg (Nadir90); (2) SBP decrease ≥20 mmHg from baseline (Fall20); and (3) SBP decrease ≥20 mmHg and/or mean arterial pressure decrease ≥10 mmHg (Fall20/MAP10). The developed models use 30 min information to predict an IDH event in the following 10 min window. Area under the receiver operating characteristic curves (AUROCs) and precision-recall curves were used to compare machine learning and deep learning models by logistic regression, XGBoost, and convolutional neural networks.

Results

Among 344,714 segments, 9,154 (2.7%), 134,988 (39.2%), and 149,674 (43.4%) IDH events occurred according to three different IDH definitions (Nadir90, Fall20, and Fall20/MAP10, respectively). Compared with models including logistic regression, random forest, and XGBoost, the deep learning model achieved the best performance in predicting IDH (AUROCs: Nadir90, 0.905; Fall20, 0.864; Fall20/MAP10, 0.863) only using measurements from hemodialysis machine during dialysis session.

Conclusions

The deep learning model performed well only using monitoring measurement of hemodialysis machine in predicting IDH without any personal information that could risk privacy infringement.

Long-Term Beta-Blocker Therapy in Patients With Stable Coronary Artery Disease After Percutaneous Coronary Intervention

Background

It is unclear whether beta-blocker treatment is advantageous in patients with stable coronary artery disease (CAD) who underwent percutaneous coronary intervention (PCI). We evaluated the clinical impact of long-term beta-blocker maintenance in patients with stable CAD after PCI with drug-eluting stent (DES).

Methods

From a nationwide cohort database, we identified the stable CAD patients without current or prior history of myocardial infarction or heart failure who underwent DES implantation. An intention-to-treat principle was used to analyze the impact of beta-blocker treatment on long-term outcomes of major adverse cardiovascular events (MACE) composed of cardiovascular death, myocardial infarction, and hospitalization with heart failure.

Results

After stabilized inverse probability of treatment weighting, a total of 78,380 patients with stable CAD was enrolled; 45,746 patients with and 32,634 without beta-blocker treatment. At 5 years after PCI with a 6-month quarantine period, the adjusted incidence of MACE was significantly higher in patients treated with beta-blockers [10.0 vs. 9.1%; hazard ratio (HR) 1.11, 95% CI 1.06–1.16, p &lt; 0.001] in an intention-to-treat analysis. There was no significant difference in all-cause death between patients treated with and without beta-blockers (8.1 vs. 8.2%; HR 0.99, 95% CI 0.94–1.04, p = 0.62). Statistical analysis with a time-varying Cox regression and rank-preserving structure failure time model revealed similar results to the intention-to-treat analysis.

Conclusions

Among patients with stable CAD undergoing DES implantation, long-term maintenance with beta-blocker treatment might not be associated with clinical outcome improvement.

Trial Registration

ClinicalTrial.gov (NCT04715594).

Long-Term Clinical Outcomes Between Biodegradable and Durable Polymer Drug-Eluting Stents: A Nationwide Cohort Study

Background

Despite the theoretical benefits of biodegradable polymer drug-eluting stents (BP-DES), clinical benefits of BP-DES over durable polymer DES (DP-DES) have not been clearly demonstrated. Using data from a large-volume nationwide cohort, we compared long-term clinical outcomes between BP-DES- and DP-DES-treated patients.

Methods

A retrospective cohort study that enrolled all patients who underwent percutaneous coronary intervention (PCI) with new-generation DES between 2010 and 2016 in Korea was conducted by using the National Health Insurance Service database. The outcomes of interest were all-cause death, cardiovascular death, and myocardial infarction (MI).

Results

A total of 127,731 patients treated with new-generation DES with thin struts (<90 μm) were enrolled for this analysis. After stabilized inverse probability of treatment weighting, the incidence of all-cause death was significantly lower in patients treated with BP-DES (n = 19,521) at 5 years after PCI (11.3 vs. 13.0% in those treated with DP-DES [n = 108,067], hazard ratio [HR] 0.92, 95% confidence interval [CI], 0.88–0.96, p < 0.001), while showing no statistically significant difference at 2 years after PCI (5.7 vs. 6.0%, respectively, HR 0.95, 95% CI, 0.89–1.01, p = 0.238). Similarly, use of BP-DES was associated with a lower incidence of cardiovascular death (7.4 vs. 9.6% in those treated with DP-DES, HR 0.82, 95% CI, 0.77–0.87, p < 0.001), and MI (7.4 vs. 8.7%, respectively, HR 0.90, 95% CI, 0.86–0.94, p = 0.006) at 5 years after PCI. There was no statistically significant difference of cardiovascular death (4.6 vs. 4.9%, respectively, HR 0.93, 95% CI, 0.85–1.01, p = 0.120) and MI (5.0 vs. 5.1%, respectively, HR 0.98, 95% CI, 0.92–1.05, p = 0.461) at 2 years after PCI.

Conclusions

Implantation of BP-DES was associated with a lower risk of all-cause death, cardiovascular death, and MI compared with DP-DES implantation. This difference was clearly apparent at 5 years after DES implantation.

Clinical Trial Registration

ClinicalTrial.gov, NCT04715594.

Ticagrelor Monotherapy After 3-Month Dual Antiplatelet Therapy in Acute Coronary Syndrome by High Bleeding Risk: The Subanalysis From the TICO Trial

This study demonstrated that for acute coronary syndrome patients treated with drug eluting stents, high bleeding risk (HBR) was associated with higher rates of net adverse clinical events (NACEs), not only including bleeding but also ischemic events. Ticagrelor monotherapy after 3-month dual antiplatelet therapy (DAPT) was associated with lower rates of NACEs and major bleeding than ticagrelor-based 12-month DAPT regardless of HBR, with no significant interaction between therapy and HBR. These findings were consistent regardless of HBR definition by Academic Research Consortium for HBR criteria or by Predicting Bleeding Complications in Patients Undergoing Stent Implantation and Subsequent DAPT score.

Background and Objectives

Identifying patients with high bleeding risk (HBR) is important when making decisions for antiplatelet therapy strategy. This study evaluated the impact of ticagrelor monotherapy after 3-month dual antiplatelet therapy (DAPT) according to HBR in acute coronary syndrome (ACS) patients treated with drug eluting stents (DESs).

Methods

In this post-hoc analysis of the TICO trial, HBR was defined by 2 approaches: meeting Academic Research Consortium for HBR (ARC-HBR) criteria or Predicting Bleeding Complications in Patients Undergoing Stent Implantation and Subsequent DAPT (PRECISE-DAPT) score ≥25. The primary outcome was a 3–12 months net adverse clinical event (composite of major bleeding and adverse cardiac and cerebrovascular events).

Results

Of the 2,980 patients without adverse events during the first 3 months after DES implantation, 453 (15.2%) were HBR by ARC-HBR criteria and 504 (16.9%) were HBR by PRECISE-DAPT score. The primary outcome rate was higher in HBR versus non-HBR patients (by ARC-HBR criteria: hazard ratio [HR], 2.87; 95% confidence interval [CI], 1.76–4.69; p<0.001; by PRECISE-DAPT score: HR, 3.09; 95% CI, 1.92–4.98; p<0.001). Ticagrelor monotherapy after 3-month DAPT was associated with lower primary outcome rate than ticagrelor-based 12-month DAPT regardless of HBR by ARC-HBR criteria, with similar magnitudes of therapy effect for HBR and non-HBR patients (p-interaction=0.400). Results were consistent by PRECISE-DAPT score (p-interaction=0.178).

Conclusions

In ACS patients treated with DESs, ticagrelor monotherapy after 3-month DAPT was associated with lower rate of adverse clinical outcomes regardless of HBR, with similar magnitudes of therapy effect between HBR and non-HBR.

Trial Registration

ClinicalTrials.gov Identifier: NCT02494895

Effect of Ticagrelor Monotherapy vs Ticagrelor With Aspirin on Major Bleeding and Cardiovascular Events in Patients With Acute Coronary Syndrome: The TICO Randomized Clinical Trial

IMPORTANCE

Discontinuing aspirin after short-term dual antiplatelet therapy (DAPT) was evaluated as a bleeding reduction strategy. However, the strategy of ticagrelor monotherapy has not been exclusively evaluated in patients with acute coronary syndromes (ACS).

OBJECTIVE

To determine whether switching to ticagrelor monotherapy after 3 months of DAPT reduces net adverse clinical events compared with ticagrelor-based 12-month DAPT in patients with ACS treated with drug-eluting stents.

DESIGN, SETTING, AND PARTICIPANTS

A randomized multicenter trial was conducted in 3056 patients with ACS treated with drug-eluting stents between August 2015 and October 2018 at 38 centers in South Korea. Follow-up was completed in October 2019.

INTERVENTIONS

Patients were randomized to receive ticagrelor monotherapy (90 mg twice daily) after 3-month DAPT (n = 1527) or ticagrelor-based 12-month DAPT (n = 1529).

MAIN OUTCOMES AND MEASURES

The primary outcome was a 1-year net adverse clinical event, defined as a composite of major bleeding and adverse cardiac and cerebrovascular events (death, myocardial infarction, stent thrombosis, stroke, or target-vessel revascularization). Prespecified secondary outcomes included major bleeding and major adverse cardiac and cerebrovascular events.

RESULTS

Among 3056 patients who were randomized (mean age, 61 years; 628 women [20%]; 36% ST-elevation myocardial infarction), 2978 patients (97.4%) completed the trial. The primary outcome occurred in 59 patients (3.9%) receiving ticagrelor monotherapy after 3-month DAPT and in 89 patients (5.9%) receiving ticagrelor-based 12-month DAPT (absolute difference, -1.98% [95% CI, -3.50% to -0.45%]; hazard ratio [HR], 0.66 [95% CI, 0.48 to 0.92]; P = .01). Of 10 prespecified secondary outcomes, 8 showed no significant difference. Major bleeding occurred in 1.7% of patients with ticagrelor monotherapy after 3-month DAPT and in 3.0% of patients with ticagrelor-based 12-month DAPT (HR, 0.56 [95% CI, 0.34 to 0.91]; P = .02). The incidence of major adverse cardiac and cerebrovascular events was not significantly different between the ticagrelor monotherapy after 3-month DAPT group (2.3%) vs the ticagrelor-based 12-month DAPT group (3.4%) (HR, 0.69 [95% CI, 0.45 to 1.06]; P = .09).

CONCLUSIONS AND RELEVANCE

Among patients with acute coronary syndromes treated with drug-eluting stents, ticagrelor monotherapy after 3 months of dual antiplatelet therapy, compared with ticagrelor-based 12-month dual antiplatelet therapy, resulted in a modest but statistically significant reduction in a composite outcome of major bleeding and cardiovascular events at 1 year. The study population and lower than expected event rates should be considered in interpreting the trial.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02494895.

Effect of Intravascular Ultrasound-Guided vs Angiography-Guided Everolimus-Eluting Stent Implantation: The IVUS-XPL Randomized Clinical Trial

IMPORTANCE

Use of intravascular ultrasound (IVUS) promotes better clinical outcomes for coronary intervention in complex coronary lesions. However, randomized data demonstrating the clinical usefulness of IVUS are limited for lesions treated with drug-eluting stents.

OBJECTIVE

To determine whether the long-term clinical outcomes with IVUS-guided drug-eluting stent implantation are superior to those with angiography-guided implantation in patients with long coronary lesions.

DESIGN, SETTING, AND PARTICIPANTS

The Impact of Intravascular Ultrasound Guidance on Outcomes of Xience Prime Stents in Long Lesions (IVUS-XPL) randomized, multicenter trial was conducted in 1400 patients with long coronary lesions (implanted stent ≥28 mm in length) between October 2010 and July 2014 at 20 centers in Korea.

INTERVENTIONS

Patients were randomly assigned to receive IVUS-guided (n = 700) or angiography-guided (n = 700) everolimus-eluting stent implantation.

MAIN OUTCOMES AND MEASURES

Primary outcome measure was the composite of major adverse cardiac events, including cardiac death, target lesion-related myocardial infarction, or ischemia-driven target lesion revascularization at 1 year, analyzed by intention-to-treat.

RESULTS

One-year follow-up was complete in 1323 patients (94.5%). Major adverse cardiac events at 1 year occurred in 19 patients (2.9%) undergoing IVUS-guided and in 39 patients (5.8%) undergoing angiography-guided stent implantation (absolute difference, -2.97% [95% CI, -5.14% to -0.79%]) (hazard ratio [HR], 0.48 [95% CI, 0.28 to 0.83], P = .007). The difference was driven by a lower risk of ischemia-driven target lesion revascularization in patients undergoing IVUS-guided (17 [2.5%]) compared with angiography-guided (33 [5.0%]) stent implantation (HR, 0.51 [95% CI, 0.28 to 0.91], P = .02). Cardiac death and target lesion-related myocardial infarction were not significantly different between the 2 groups. For cardiac death, there were 3 patients (0.4%) in the IVUS-guided group and 5 patients (0.7%) in the angiography-guided group (HR, 0.60 [95% CI, 0.14 to 2.52], P = .48). Target lesion-related myocardial infarction occurred in 1 patient (0.1%) in the angiography-guided stent implantation group (P = .32).

CONCLUSIONS AND RELEVANCE

Among patients requiring long coronary stent implantation, the use of IVUS-guided everolimus-eluting stent implantation, compared with angiography-guided stent implantation, resulted in a significantly lower rate of the composite of major adverse cardiac events at 1 year. These differences were primarily due to lower risk of target lesion revascularization.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01308281.

Differential impact of unrecognised brain infarction on stroke outcome in non-valvular atrial fibrillation

There has been little information regarding the impact of unrecognised brain infarctions (UBIs) on stroke outcome in patients with non-valvular atrial fibrillation (NVAF). By using volumetric analysis of ischaemic lesions, we evaluated the potential impact of UBIs on clinical outcome according to their presence and categorised type. This study enrolled 631 patients with NVAF having no clinical stroke history. UBIs were categorised into three types as territorial, lacunar, or subcortical. We collected stroke severity, functional outcome at three months, and the total volume of UBIs and acute infarction lesions. We investigated the association between clinical outcome and the type or volume of UBI, using a linear mixed model and logistic regression analysis. UBIs were detected in 285 (45.2 %) patients; territorial UBIs were observed in 24.4 % of patients (154/631), lacunar UBIs in 25 % (158/631), and subcortical UBIs in 15.7 % (99/631). Although initial stroke severity was not different between patients with UBIs and those without, those with UBIs had less improvement during hospitalisation, leading to poorer outcome at three months. Among the three types of UBIs, only territorial UBIs were associated with poor outcome, especially in patients with relatively smaller acute infarction volume. UBIs, in particular, territorial UBIs, may be considered as predictors for poor outcome after ischaemic stroke in patients with NVAF. Our results suggest that the impact of UBIs on clinical outcome differs according to the type of UBIs and the acute stroke severity.

The frequency of cerebral microbleeds increases with CHADS(2) scores in stroke patients with non-valvular atrial fibrillation

BACKGROUND AND PURPOSE

Cerebral microbleeds (CMBs) are extravasations of blood from lipohyalinized or amyloid angiopathic cerebral arterioles, and the presence and numbers of CMBs are significantly associated with the development of oral anticoagulation (OA)-related intracranial haemorrhage (ICH). The aim of this study was to investigate whether there is a difference in CMBs burden according to CHADS(2) scores or CHA(2) DS(2) -VASc scores in non-valvular atrial fibrillation (NVAF) patients.

METHODS

We included 550 ischaemic stroke patients who had NVAF and who had undergone brain magnetic resonance imaging (MRI) with gradient-recalled echo (GRE) T2 sequences from our prospective stroke registry between January 2005 and November 2011. We calculated CHADS(2) scores and CHA(2) DS(2) -VASc scores for all patients based on their underlying cardiovascular diseases. The presence, location and number of CMBs were assessed in each patient. We also investigated whether the CMBs were actually associated with the development of ICH during follow-up.

RESULTS

The mean patient age was 70.4 ± 10.5 years, and 324 (58.9%) patients were men. One-hundred and seventy-three patients (31.5%) had CMBs detected on GRE MRI. Higher CHADS(2) scores or CHA(2) DS(2) -VASc scores were strongly associated with the presence and number of CMBs. During follow-up of median 3.1 ± 1.6 years, the presence of CMBs was independently associated with the development of ICH, whilst the CHADS(2) scores or CHA(2) DS(2) -VASc scores were not.

CONCLUSIONS

Considering the positive association between the presence of CMBs and OA-related ICH, our results suggest that the increase in ICH in high-risk groups during OA may be related to an increased burden of CMBs.

The socioeconomic burden of coronary heart disease in Korea

OBJECTIVES

We aimed to estimate the annual socioeconomic burden of coronary heart disease (CHD) in Korea in 2005, using the National Health Insurance (NHI) claims data.

METHODS

A prevalence-based, top-down, cost-of-treatment method was used to assess the direct and indirect costs of CHD (International Classification of Diseases, 10th revision codes of I20-I25), angina pectoris (I20), and myocardial infarction (MI, I21-I23) from a societal perspective.

RESULTS

Estimated national spending on CHD in 2005 was $2.52 billion. The majority of the spending was attributable to medical costs (53.3%), followed by productivity loss due to morbidity and premature death (33.6%), transportation (8.1%), and informal caregiver costs (4.9%). While medical cost was the predominant cost attribute in treating angina (74.3% of the total cost), premature death was the largest cost attribute for patients with MI (66.9%). Annual per-capita cost of treating MI, excluding premature death cost, was $3183, which is about 2 times higher than the cost for angina ($1556).

CONCLUSIONS

The total insurance-covered medical cost ($1.13 billion) of CHD accounted for approximately 6.02% of the total annual NHI expenditure. These findings suggest that the current burden of CHD on society is tremendous and that more effective prevention strategies are required in Korea.

A new strategy for discontinuation of dual antiplatelet therapy: the RESET Trial (REal Safety and Efficacy of 3-month dual antiplatelet Therapy following Endeavor zotarolimus-eluting stent implantation)

OBJECTIVES

The goal of this study was to evaluate shorter duration (3 months) dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation.

BACKGROUND

There have been few published reports of prospective randomized clinical studies comparing the safety and efficacy of shorter duration DAPT after DES implantation.

METHODS

We randomly assigned 2,117 patients with coronary artery stenosis into 2 groups according to DAPT duration and stent type: 3-month DAPT following Endeavor zotarolimus-eluting stent (E-ZES) implantation (E-ZES+3-month DAPT, n=1,059) versus 12-month DAPT following the other DES implantation (standard therapy, n=1,058). We hypothesized that the E-ZES+3-month DAPT would be noninferior to the standard therapy for the primary composite endpoint (cardiovascular death, myocardial infarction, stent thrombosis, target\vessel revascularization, or bleeding) at 1 year.

RESULTS

The primary endpoint occurred in 40 (4.7%) patients assigned to E-ZES+3-month DAPT compared with 41 (4.7%) patients assigned to the standard therapy (difference: 0.0%; 95% confidence interval [CI]: -2.5 to 2.5; p=0.84; p<0.001 for noninferiority). The composite rates of any death, myocardial infarction, or stent thrombosis were 0.8% and 1.3%, respectively (difference: -0.5%; 95% CI: -1.5 to 0.5; p=0.48). The rates of stent thrombosis were 0.2% and 0.3%, respectively (difference: -0.1%; 95% CI: -0.5 to 0.3; p=0.65) without its further occurrence after cessation of clopidogrel in the E-ZES+3-month DAPT group. The rates of target vessel revascularization were 3.9% and 3.7%, respectively (difference: 0.2%; 95% CI: -2.3 to 2.6; p=0.70).

CONCLUSIONS

E-ZES+3-month DAPT was noninferior to the standard therapy with respect to the occurrence of the primary endpoint. (REal Safety and Efficacy of a 3-month dual antiplatelet Therapy following E-ZES implantation [RESET]; NCT01145079).

Sex differences in the relationship between socioeconomic status and metabolic syndrome: the Korean National Health and Nutrition Examination Survey

AIMS

To investigate sex differences in the relationship between socioeconomic status (SES) and the prevalence of metabolic syndrome (MetS) in Korean adults.

METHODS

We examined the relationship between SES, as measured by household income or education level, and the prevalence of MetS in Korean adults who participated in the 2007-2008 Korean National Health Examination and Nutrition Survey (KNHANES). The adjusted odds ratios (ORs) for MetS were calculated using multivariate logistic regression analysis across household income and education level quartiles.

RESULTS

We found significant differences between men and women in the association between SES and MetS, with a positive association for men and an inverse association for women. The adjusted OR and 95% confidence interval (95% CI) for MetS for the highest vs. lowest quartile of household income was 1.59 (1.15-2.20) in men. The adjusted ORs for MetS for the highest vs. lowest quartile of household income and education level were 0.54 (0.41-0.72) and 0.26 (0.17-0.38) in women, respectively.

CONCLUSIONS

We found sex differences in the relationship between SES and the prevalence of MetS in Korea. These findings suggest that sex-specific public health interventions that consider SES are needed for the prevention and treatment of MetS.

The use of complementary and alternative medicine (CAM) in children: a telephone-based survey in Korea

BACKGROUND

The purpose of this study was to estimate the prevalence and patterns of CAM use in Korean children via a telephone based survey. We also investigated parent satisfaction, a proxy for their child, with CAM therapy and determined the factors affecting satisfaction with CAM use.

METHODS

This study used a landline telephone-based survey to examine a random sample representative of Korean children, aged 0 to 18 years. We assigned and surveyed 2,000 subjects according to age group, gender, and geographical distributions by proportionate quota and systematic sampling of children throughout Korea in 2010. A household of 1,184 with a 18.6% response rate was projected to yield 2,077 completed data. We performed statistical analyses using sampling weight.

RESULTS

The prevalence of CAM use was 65.3% for the Korean children in our sample population. The most commonly used CAM category was natural products (89.3%). More than half of CAM user's parents reported satisfaction with their therapies (52.7%), but only 29.1% among them had consulted a Western trained doctor regarding the CAM therapies used. Doctor visits were associated with lower satisfaction with CAM use but not with consultation rate with a doctor.

CONCLUSIONS

Our study suggests that CAM is widely used among children in Korea. Medical doctors should actively discuss the use of CAM therapies with their patients and provide information on the safety and efficacy of diverse CAM modalities to guide the choices of CAM users.

Use of a handheld, computerized device as a decision support tool for stroke classification

BACKGROUND

The Trial of ORG 10172 in Acute Stroke Treatment (TOAST) classification has been widely used to determine etiology of ischemic stroke. However, interrater reliability is known to be modest. The complexity of abstraction and the interpretation of various clinical and laboratory data might limit the accuracy of the TOAST classification. In this study, we developed a computerized clinical decision support system for stroke classification that can be used in a handheld device and tested whether this system can improve diagnostic accuracy and reliability.

METHODS

Based on the TOAST classification, a logical algorithm was developed and implemented on a handheld device, named iTOAST. After answering six questions using the touch interface, the stroke subtype result is displayed on the screen. Four neurology residents were randomly assigned to classify stroke subtypes using iTOAST or the conventional method (cTOAST). Using a crossover design, they classified the stroke subtypes of 70 patients. The standard subtypes were determined by three stroke experts. Correlated kappa coefficients using iTOAST compared with cTOAST were determined.

RESULTS

The kappa (SE) value of iTOAST [0.790 (0.041), 95% CI: 0.707-0.870] was higher than that of cTOAST [0.692 (0.046), 95% CI: 0.600-0.782] (P<0.001). Neither sequence (P=0.857) nor period effect (P=0.999) was observed.

CONCLUSIONS

The stroke classification tool using a handheld, computerized device was easy, accurate, and reliable over the conventional method. It may have additional benefit because a handheld, computerized device is accessible anytime and anywhere.

Early neurological outcomes according to CHADS2 score in stroke patients with non-valvular atrial fibrillation

BACKGROUND AND PURPOSE

A higher CHADS(2) score or CHA(2)DS(2)-VASc score is associated with an increased risk of ischaemic stroke in patients with non-valvular atrial fibrillation (NVAF). However, there are no data regarding early neurological outcomes after stroke according to the risk levels.

METHODS

In this study, a total of 649 stroke patients with NVAF were enrolled and categorized into three groups: low-risk (CHADS(2) score of 0-1), moderate-risk (CHADS(2) score 2-3), or high-risk group (CHADS(2) score ≥4). CHA(2)DS(2)-VASc score was divided into four groups including 0-1, 2-3, 4-5, and ≥6. We investigated whether there were differences in initial stroke severity, early neurological outcome, and infarct size according to CHADS(2) score or CHA(2)DS(2)-VASc score in stroke patients with NVAF.

RESULTS

The initial National Institutes of Health Stroke Scale (NIHSS) score was highest in high-risk group [9.5, interquartile range (IQR) 4-18], followed by moderate-risk (8, IQR 2-17) and low-risk group (6, IQR 2-15) (P=0.012). Likewise, initial stroke severity increased in a positive fashion with increasing the CHA(2)DS(2)-VASc score. During hospitalization, those in the high-risk group or higher CHA(2)DS(2)-VASc score had less improvement in their NIHSS score. Furthermore, early neurological deterioration (END) developed more frequently as CHADS(2) score or CHA(2)DS(2)-VASc score increased. Multivariate analysis showed being in the high-risk group was independently associated with END (OR 2.129, 95% CI 1.013-4.477).

CONCLUSIONS

Our data indicate that patients with NVAF and higher CHADS(2) score or CHA(2)DS(2)-VASc score are more likely to develop severe stroke and a worse clinical course is expected in these patients after stroke presentation.

The effect of age on motor deficits and cerebral glucose metabolism of Parkinson's disease

BACKGROUND

No systematic study has been made to separate age-related clinical deterioration and dysfunctional brain areas from those associated with Parkinson's disease (PD).

METHODS

This study included 73 de novo patients with PD and 43 age-matched controls. All subjects underwent [(18)F]-fluorodeoxy glucose (FDG) positron emission tomography studies. The severity of parkinsonian motor deficit was measured using unified PD rating scale (UPDRS) motor scores. Multiple linear regression analysis was used to identify those parkinsonian motor deficits for which severity was correlated with the age of the patients and to locate brain areas in which normalized FDG uptake values were inversely correlated with the age of the subjects.

RESULTS

Patient age was positively correlated with total UPDRS motor scores and with subscores for bradykinesia and axial motor deficits, but not with subscores for tremor and rigidity. In the control group, an age-related decline in glucose uptake was found only in the cingulate cortex. However, in the patient group, an inverse correlation between age and glucose uptake was observed in the prefrontal, cingulate, orbitofrontal, perisylvian areas, caudate, and thalamus.

CONCLUSIONS

In PD, widespread age-related decline in cerebral function may exaggerate the deterioration associated with bradykinesia and the axial motor deficits associated with nigral neuronal loss.

External validation of nomogram for the prediction of recurrence after curative resection in early gastric cancer

BACKGROUND

Nomograms are statistics-based tools that provide the overall probability of a specific outcome. In our previous study, we developed a nomogram that predicts recurrence of early gastric cancer (EGC) after curative resection. We carried out this study to externally validate our EGC nomogram.

PATIENTS AND METHODS

The EGC nomogram was established from a retrospective EGC database that included 2923 consecutive patients. This nomogram was independently externally validated for a cohort of 1058 consecutive patients. For the EGC nomogram validation, we assessed both discrimination and calibration.

RESULTS

Within the follow-up period (median 37 months), a total of 11 patients (1.1%) experienced recurrence. The concordance index (c-index) was 0.7 (P = 0.02) and the result of the overall C index was 0.82 [P = 0.006, 95% confidence interval (CI) 0.59-1.00]. The goodness of fit test showed that the EGC nomogram had significantly good fit for 1- and 2-year survival intervals (P = 0.998 and 0.879, respectively). The actual and predicted survival outcomes showed good agreement, suggesting that the survival predictions from the nomogram are well calibrated externally.

CONCLUSIONS

A preexisting nomogram for predicting disease-free survival (DFS) of EGC after surgery was externally validated. The nomogram is useful for accurate and individual prediction of DFS, patient prognostication, counseling, and follow-up planning.

Empirical test of an explanatory theory of postpartum fatigue in Korea

AIM

This paper is a report of a study designed to test an explanatory theory of postpartum fatigue.

BACKGROUND

Postpartum fatigue is influenced by various factors and affects a mother's performance. A full understanding of postpartum fatigue is very important for developing effective nursing strategies to reduce postpartum fatigue and enhance mothers' performance.

METHODS

Healthy postpartum women were recruited from five medical centers and one midwifery office in urban area in Korea (n = 291) by convenience sampling. Data were collected at 4- to 8-week follow-up visits after childbirth in 2006, using a self-report questionnaire. The proposed fatigue theory incorporated postpartum fatigue, postpartum depression, sleep quality, childcare stress, unsatisfactory feeding, social support, infant difficulty and satisfaction with Sanhujori, the Korean traditional postpartum care provided for 3 weeks following delivery by non-professional caregivers. Structural equation modelling was used to test the explanatory theory of postpartum fatigue.

RESULTS

The modified fatigue theory showed good fit and high compatibility with the empirical data. In the final explanatory theory, postpartum depression and sleep quality directly affected postpartum fatigue, while childcare stress and the cultural phenomenon of Sanhujori had indirect effects on postpartum fatigue, via postpartum depression and sleep quality respectively.

CONCLUSION

These findings suggest the potential role of comprehensive nursing focused on decreasing postpartum depression and improving sleep quality as a way to decrease postpartum fatigue. Also, nursing strategies for decreasing childcare stress and enhancing Sanhujori satisfaction may be helpful in reducing postpartum fatigue in Korean mothers.

Effect of warfarin withdrawal on thrombolytic treatment in patients with ischaemic stroke

BACKGROUND AND PURPOSE

  Abruptly discontinuing warfarin may induce a rebound prothrombotic state. Thrombolytic agents may also paradoxically induce prothrombotic conditions, which include platelet activation and thrombin generation. Therefore, prothrombotic states may be enhanced by withdrawing warfarin in patients under thrombolytic treatment. This study was aimed to determine whether patients with warfarin withdrawal have different clinical outcomes from those without warfarin use after thrombolytic treatment.

METHODS

  A total of 148 consecutive patients with atrial fibrillation who were not on anticoagulants at admission and who received thrombolysis were included in this study. We compared the outcomes between a warfarin withdrawal group and a no-warfarin group.

RESULTS

  Fourteen patients (9.5%) were included in the warfarin withdrawal group. Although baseline National Institute of Health Stroke Scale (NIHSS) scores, recanalization rates, and hemorrhage frequencies did not differ between the groups, the warfarin withdrawal group showed poorer outcomes. Increased NIHSS scores during the first 7days were more frequent in the warfarin withdrawal group (57.1% vs. 26.9%, P=0.029). The median percent improvement in NIHSS scores at 24h after thrombolysis was also lower in the warfarin withdrawal group. After adjusting for covariates, warfarin withdrawal was a strong predictor of poor functional outcome at 3months (modified Rankin score≥3) (odds ratio, 17.067, 95% CI 2.703-107.748).

CONCLUSIONS

  Discontinuing warfarin was associated with early neurologic deterioration and poor long-term outcomes after thrombolytic treatment.

Failure of complete recanalization is associated with poor outcome after cardioembolic stroke

BACKGROUND

  Recanalization is strongly associated with outcomes after thrombolytic treatment. Cardiac emboli are known as better response to fibrinolytic agents because they are fibrin-rich; however, cardioembolic stroke itself is associated with poor outcomes and high mortality. Completeness of recanalization may therefore affect the outcome of cardioembolic stroke. We investigated whether degree of recanalization influences outcomes following fibrinolytic therapy in cardioembolic stroke.

METHODS

  Consecutive stroke patients with relevant artery occlusions on baseline CT angiography who had received thrombolytic treatment were enrolled. Completeness of recanalization was assessed by the Thrombolysis in Myocardial Infarction (TIMI) grade, which was compared between patients with and without cardiac sources of embolism (CSE). We also investigated independent predictors of poor outcome (modified Rankin scale score 3-6) at 3 months.

RESULTS

  Of the 127 patients enrolled, 65 (51%) had one or more CSE. Although the overall recanalization rates (TIMI 2 or 3) in patients with CSE (65%) and patients without CSE (68%) were similar (P=0.710), patients with CSE were less likely to show complete recanalization (TIMI 3) compared with those without CSE (19% vs. 39%, P=0.011). Multivariate analysis revealed that CSE was associated with failure of complete recanalization (OR 2.809, 95% CI 1.097-7.192) and was an independent predictor of poor outcome at 3months (OR 3.629, 95% CI 1.205-8.869).

CONCLUSIONS

  In cardioembolic strokes, failure of complete recanalization following thrombolytic therapy was frequent and was associated with poor outcome after thrombolysis.

[An epidemiological analysis of hepatitis A virus serologic markers during the recent four years in Korea]

BACKGROUND

To establish effective preventive measures for hepatitis A virus (HAV) infection, a nationwide epidemiologic study on seroprevalence of anti-HAV and the disease prevalence is needed. The aim of this study was to analyze the recent sero-epidemiological changes of hepatitis A markers in Korea.

METHODS

The results of 11,068 anti-HAV total and 32,360 anti-HAV IgM tests by electro-chemiluminescence immunoassay (ECLIA) that had been requested in recent four years (2005-2008) to a reference medical laboratory from 1,699 institutions nationwide were retrospectively analyzed according to the distribution of year, sex, and age groups.

RESULTS

The overall positive rate of anti-HAV total was 62.8%. The overall positive rate of anti-HAV IgM was 11.0%, showing a significantly increasing trend by year: 7.7%, 10.9%, 8.9%, and 14.3% in 2005, 2006, 2007, and 2008, respectively (P<0.0001). The positive rate of anti-HAV IgM was higher in male than in female subjects (11.8% vs 10.0%, P<0.0001), and 81.8% (2,916/3,566) of the anti-HAV IgM positive results were observed in the age groups of 21-40 yr. The annual positive rates of anti-HAV total and anti-HAV IgM showed significantly decreasing and increasing trends, respectively, in the age groups of > or = 21 yr.

CONCLUSION

In accordance with a decreasing sero-positivity of anti-HAV total, the prevalence of acute hepatitis A virus infection has been considerably increased during the recent four years in the age groups of > or = 21 yr. The results of this study could be used effectively as a basic data for establishing effective preventive measures for hepatitis A including vaccination in these susceptible age groups.

[Socioeconomic costs of stroke in Korea: estimated from the Korea national health insurance claims database]

OBJECTIVES

To estimate the annual socioeconomic costs of stroke in Korea in 2005 from a societal perspective.

METHODS

We identified those 20 years or older who had at least one national health insurance (NHI) claims record with a primary or a secondary diagnosis of stroke (ICD-10 codes: I60-I69, G45) in 2005. Direct medical costs of the stroke were measured from the NHI claims records. Direct non-medical costs were estimated as transportation costs incurred when visiting the hospitals. Indirect costs were defined as patients' and caregivers' productivity loss associated with office visits or hospitalization. Also, the costs of productivity loss due to premature death from stroke were calculated.

RESULTS

A total of 882,143 stroke patients were identified with prevalence for treatment of stroke at 2.44%. The total cost for the treatment of stroke in the nation was estimated to be 3,737 billion Korean won (KRW) which included direct costs at 1,130 billion KRW and indirect costs at 2,606 billion KRW. The per-capita cost of stroke was 3 million KRW for men and 2 million KRW for women. The total national spending for hemorrhagic and ischemic stroke was 1,323 billion KRW and 1,553 billion KRW, respectively, which together consisted of 77.0% of the total cost for stroke. Costs per patient for hemorrhagic and ischemic stroke were estimated at 6 million KRW and 2 million KRW, respectively.

CONCLUSIONS

Stroke is a leading public health problem in Korea in terms of the economic burden. The indirect costs were identified as the largest component of the overall cost.

Breast-feeding in South Korea: factors influencing its initiation and duration

Objective

To investigate factors influencing the practices of partial breast-feeding (PBF) and exclusive breast-feeding (EBF).

Design

A national, cross-sectional survey was conducted among married women aged 15–49 years from May to August 2003.

Setting

South Korea.

Subjects

A total of 865 mothers answered questions regarding the feeding practices of their youngest baby, born between January 2001 and May 2003.

Results

The initiation rates of PBF and EBF were 81% and 63%, respectively. However, the median durations of PBF and EBF were very short: 12 and 8 weeks, respectively. According to stepwise logistic and Cox regression analyses, the more prenatal care women received, the more likely they were to initiate PBF and EBF but the less likely to continue EBF. Delivery by Caesarean section decreased the initiation of PBF and EBF. The mother’s education level and employment status before marriage, the amount of prenatal care, delivery method and baby’s status at birth affected breast-feeding initiation, whereas the amount of prenatal care influenced breast-feeding duration.

Conclusion

To promote breast-feeding, education and campaigning on the importance of continued breast-feeding should be provided to the general public, particularly to health workers in maternity units.

A comparison of perinatal mortality in Korea on holidays and working days

OBJECTIVE

To examine whether the perinatal mortality of infants born during holidays differs from that of infants born on workdays, and to elucidate its cause.

DESIGN

Cross-sectional study. Setting Vital statistics linked to the National Infant Mortality Survey data for 1999 births in Korea.

POPULATION

In all, 628 485 births in 1999 in Korea.

METHODS

Number of births and perinatal mortality were classified according to the day of the week using the occurrence index. After adjusting for confounding factors, the odds ratios (ORs) for increased holiday mortality were estimated using logistic regression.

MAIN OUTCOME MEASURE

Birthweight-adjusted perinatal mortality.

RESULTS

Births on holidays were 33% fewer and perinatal deaths 24% higher than expected (PMR, Perinatal Mortality Rate, 16.4 versus 12.8; OR, 1.3; 95% CI, 1.2-1.4). After the adjustment of birthweight, gender, plurality and congenital anomalies, the odds ratio for death of infants born during holidays was 1.2 (95% CI, 1.1-1.3).

CONCLUSIONS

The higher perinatal mortality during holidays in Korea appears to be due to different qualities of perinatal care, rather than difference in case-mix.

White blood cell count and the risk of colon cancer

Inflammation may be linked to the pathogenesis of colorectal cancer. However, two conflicting observational results were recently reported on the relationship between the inflammatory marker C-reactive protein (CRP) and the risk of colorectal cancer. Few epidemiologic studies have examined the association between inflammatory markers and the risk of colorectal cancer. We prospectively examined the mortality and incidence risk for colon and rectal cancers among 424,419 Koreans (108,907 men and 315,512 women). The subjects were 40 to 95 years of age and from the Korean Cancer Prevention Study (KCPS) cohort. All subjects received medical examination from the National Health Insurance Corporation in 1993 and 1995. The maximum follow-up period was 10 years, and the follow-up periods began in January 1, 1994 and ended in December 31, 2003. An elevated white blood cell count (WBC) was associated with a higher mortality risk of colon cancer (highest versus lowest quartile: men, 1.55, 95% CI 1.10-2.18, p for trend = 0.0014; women, 1.51, 95% CI 1.12- 2.03, p for trend = 0.0049). Similarly, an elevated WBC was associated with a higher incidence risk of colon cancer (highest versus lowest quartile: men, 1.38, 1.09-1.76, p for trend = 0.0017; women, 1.46, 95% CI 1.20-1.78, p for trend= 0.0003). A positive linear trend was also observed in non- smokers. There was no significant association between WBC and the risk of rectal cancer. Our findings demonstrate that an elevated WBC is associated with an increase in both the mortality and incidence rates of colon cancer. These results support our hypothesis that inflammation increases the risk of colon cancer.

The prevalence of hepatitis C virus infection in Korea: pooled analysis

This study evaluated the prevalence of hepatitis C virus (HCV) infections in Korea. Pooled estimates of the anti-HCV positivity were calculated using the data published in 15 reports on the general population and health check-up examinees. The overall pooled estimate of the prevalence of HCV among middle-aged adults (40 yr old and above) was 1.68% (95% confidence interval: 1.51-1.86%) during the year of 1990-2000 among the general population. Most of the published data indicated that the prevalence of anti-HCV increased with age. The anti-HCV positivity was significantly higher in females than in males. Because the risk of HCV exposure in blood recipients has decreased remarkably, the spread of HCV through means other than a transfusion must be prevented.

Economic burden of smoking in Korea

OBJECTIVE

To support tobacco control policies in Korea by providing the estimated annual economic burden attributed to cigarette smoking.

METHODS

The following two different approaches were used to estimate the cost: "disease specific" and "all causes". In the disease specific approach, we focused on estimating direct and indirect costs involved in treatments of cardiovascular, respiratory, and gastrointestinal diseases, and cancer as a result of smoking, by using an epidemiologic approach-the population attributable risk (PAR). To compute PAR, the relative risks of smoking in terms of physician visits, hospital admission, and death were estimated using the Cox proportional hazard model. In the all causes approach, we examined the differences in direct and indirect costs between smokers and non-smokers for all conditions and types of disease. The major data source was the Korea Medical Insurance Corporation cohort study, which had complete records of smoking status as of 1992 for 115 682 male and 67 932 female insured workers.

RESULTS

By the disease specific approach, the estimated costs attributable to smoking in 1998 in Korea ranged from US 2269.42 million dollars (4.89 million dollars per 100,000 population; 0.59% of gross domestic product (GDP)) to 2956.75 million dollars (6.37 million dollars; 0.78% of GDP). The all causes approach yielded a minimum cost of 3154.75 million dollars (6.79 million dollars; 0.82% GDP) and a maximum of 4580.25 million dollars (9.86 million dollars; 1.19% GDP).

CONCLUSION

The study confirms that smoking places a substantial economic burden on Korean society. In light of this, our study provides evidence for a strong need to develop a national policy to effectively control tobacco consumption in Korea.

Atherosclerosis in rheumatoid arthritis: morphologic evidence obtained by carotid ultrasound

OBJECTIVE

Recent studies have suggested increased cardiovascular disease among patients with rheumatoid arthritis (RA). We undertook this study to obtain morphologic evidence of subclinical atherosclerosis in RA patients.

METHODS

We used high-resolution B-mode ultrasound to compare carotid artery intima-media wall thickness (IMT) between 53 postmenopausal women with RA and 53 controls matched by age, sex, and menopause status. No subject in either group had a history of atherosclerosis or its complications. We investigated the association between IMT and relevant clinical and therapeutic variables, including the impact of low-dose corticosteroid therapy (< or = 10 mg/day prednisolone).

RESULTS

The mean +/- SD IMT of the left and right common carotid arteries in RA patients was significantly greater than that in controls (0.77 +/- 0.09 mm versus 0.68 +/- 0.14 mm; P < 0.001). Early RA (duration < or = 1 year) was associated with lesser IMT than was RA of longer duration (0.72 +/- 0.03 mm versus 0.78 +/- 0.01 mm; P < 0.04). Prednisolone use was not associated with increased IMT (0.78 +/- 0.02 mm in nonusers versus 0.76 +/- 0.01 mm in users; P = 0.38).

CONCLUSION

Our data indicate that RA patients have an ultrasonic marker of early atherosclerosis consistent with an increased risk for atherosclerosis.

Is body mass index the prognostic factor in breast cancer?: a meta-analysis

This study was performed to integrate the results of previous studies that investigated the relationship between body mass index (BMI) and prognosis in breast cancer. We reviewed the English literatures using the MEDLINE database from 1966 to 1999. The materials included 12 published articles with a total of 8,029 cases of breast cancer. The effect size was obtained from hazard ratio in each study. Homogeneity test was conducted before the integration of each effect size and the result demonstrated that the studies were heterogeneous. A random effect model was used to integrate the overall effect size. The integrated effect size was 1.56 (95% confidence interval, 1.22-2.00). In addition, publication bias should be accounted for because each published study was asymmetric in shape revealed by funnel plot. These results suggest that BMI have a prognostic significance in breast cancer. We believe that well-designed longitudinal studies, involving a large number of samples are required to resolve these issues.

Moderate dietary fat consumption as a risk factor for ischemic heart disease in a population with a low fat intake: a case-control study in Korean men

BACKGROUND

Dietary fat intake is associated with the incidence of ischemic heart disease (IHD) in Western countries. In populations in which both the average dietary fat consumption and the incidence of IHD are lower than in Western countries, the association of dietary fat intake with IHD incidence remains unknown.

OBJECTIVE

We conducted a case-control study to examine the association of dietary fat with IHD incidence in Korean men.

DESIGN

The case group consisted of 108 patients with electrocardiogram-confirmed myocardial infarction or angiographically confirmed (> or =50% stenosis) IHD who were admitted to a university teaching hospital in Seoul, Republic of Korea. The controls were 142 age-matched patients admitted to the departments of ophthalmology and orthopedic surgery at the same hospital. Dietary fat intake was assessed by a nutritionist using a semiquantitative food-frequency questionnaire. Body mass index (BMI), cigarette use, alcohol intake, exercise, and history of disease were determined during an interview and examination.

RESULTS

In a univariate analysis, the mean percentages of energy from total fat, saturated fatty acids, and monounsaturated fatty acids were significantly higher in the cases than in the controls. BMI, smoking, and a history of hypertension were associated with the occurrence of IHD. In multiple logistic analyses, total fat intake was a significant risk factor (odds ratio: 1.08 for 1% of energy intake; 95% CI: 1.02, 1.14) after adjustment for BMI and smoking.

CONCLUSION

In a population with a relatively low fat intake (19% of energy intake), a moderate increase in total fat intake may be a risk factor for IHD.

Low serum cholesterol and haemorrhagic stroke in men: Korea Medical Insurance Corporation Study

BACKGROUND

In some prospective studies, haemorrhagic stroke occurs more frequently in individuals with low serum cholesterol than in those with higher concentrations. We aimed to determine whether low total serum cholesterol is an independent risk factor for haemorrhagic stroke (intracerebral haemorrhage and subarachnoid haemorrhage) in South Korea, a country that has a population with relatively low concentrations of total serum cholesterol.

METHODS

We measured total serum cholesterol and other cardiovascular risk factors in 114,793 Korean men, aged between 35-59 years in 1990 and 1992, in a prospective observational study. We used data obtained in 1992 for smoking and alcohol consumption. We divided total serum cholesterol into quintiles (<4.31 mmol/L, 4.31-<4.74, 4.74-<5.16, 5.16-<5.69 and > or = 5.69). Our primary outcomes were hospital admissions and deaths from intracerebral and subarachnoid haemorrhage in a 6 year follow-up between 1993 and 1998.

FINDINGS

528 men had a haemorrhagic stroke--372 intracerebral and 98 subarachnoid haemorrhage--and 58 were unspecified strokes. The relative risks of intracerebral haemorrhage in each quintile of total serum cholesterol (lowest to highest were: 1.22 (95% CI 0.88-1.69); 0.86 (0.60-1.21); 1.08 (0.78-1.48); and 1.03 (0.75-1.41). The corresponding relative risks for subarachnoid haemorrhage were: 1.44 (0.76-2.73); 1.13 (0.59-2.20); 1.21 (0.64-2.29); and 1.12 (0.59-2.14).

INTERPRETATION

Low total serum cholesterol is not an independent risk factor for either intracerebral or subarachnoid haemorrhagic stroke in Korean men.

Comparing the survival of two groups with an intermediate clinical event

Consider a subject entered on a clinical trial in which the major endpoint is a time metric such as death or time to reach a well defined event. During the observational period the subject may experience an intermediate clinical event. The intermediate clinical event may induce a change in the survival distribution. We consider models for the one and two sample problem. The model for the one sample problem enables one to test if the occurrence of the intermediate event changed the survival distribution. This models provides a way of carrying out non-randomized clinical trial to determine if a therapy has benefit. The two sample problem considers testing if the probability distributions, with and without an intermediate event, are the same. Statistical tests are derived using a semi-Markov or a time dependent mixture model. Simulation studies are carried out to compare these new procedures with the log rank, stratified log rank and landmark tests. The new tests appear to have uniformly greater power than these competitor tests. The methods are applied to a randomized clinical trial carried out by the Aids Clinical Trial Group (ACTG) which compared low versus high doses of zidovudine (AZT).

Twelve-year tracking of blood pressure in Korean school children: the Kangwha Study

Longitudinal data from different populations have shown different degrees of tracking of blood pressure (BP). To examine BP tracking in Korean school children, 219 of 430 children (100 males, 119 females) who were 6 years old in 1986 in Kangwha County, Korea have been examined annually up to 1997 in the Kangwha Study. BP was measured twice with standard mercury sphygmomanometers and the average of the two measurements was used for the level of BP. Diastolic BP were measured at the fourth Korotkoff sound. Tracking was examined using a time-lag correlation analysis and McMahan's tracking index tau, which indicates the proportion of variation attributable to tracking apart from the natural growth component. As well the jackknife method was used to obtain the confidence interval of tau. Correlation coefficients between systolic BP from age 6 to 17 ranged from 0.39-0.54 for males and 0.44-0.57 for females. Taus for systolic BP were 0.875 (95% CI: 0.803-0.947) and 0.900 (95% CI: 0.809-0.991) in males and females, respectively. Correlation coefficients between diastolic BP from age 6 to 17 ranged from 0.28-0.47 for males and 0.14-0.47 for females. Taus for diastolic BP were 0.983 (95% CI: 0.897-1.000) and 0.800 (95% CI: 0.717-0.883) in males and females, respectively. These findings showed strong evidence for BP tracking in Korean school children from childhood to late adolescence.

Relationship between nutritional intake and dental caries experience of junior high students

This study was designed to investigate the relationship between nutritional intake and caries experience of junior high school students. The sample consisted of 295 boys and 356 girls in Kangwha county. Dependent variables were total caries experience, occlusal surface caries experience, smooth surface caries experience and DMFS score (Decayed, Missing, Filling Tooth Surface score). Independent variables such as pit and fissure retentiveness of first molars, oral hygiene status, intraoral acidogenicity were also measured by dentists. Other independent variables such as toothbrushing habits, socioeconomic conditions, between-meal eating habits, and daily nutritional intake were determined during an interview. Univariate and multivariate analysis was performed to evaluate how nutritional intake influences caries experience. The results were as follows: 1. The most influential factor on dental caries experience was pit and fissure retentiveness. 2. Dietary fiber and potassium were the significant nutritional factors on total caries experience and occlusal caries experience, and niacin was the significant nutritional factor on smooth surface caries. 3. DMFS score was positively associated with the daily amount of carbohydrate and niacin intake, and negatively associated with total energy intake. The above results suggested that pit and fissure retentiveness was the most influential factor on caries experience. However, in this study, the intake of potassium and niacin was identified to influence the caries experience in addition to confirming the well-known relationship between fiber and carbohydrate intake.