Ki Soo Park

Usefulness of the VerifyNow P2Y12 assay to evaluate the antiplatelet effects of ticagrelor and clopidogrel therapies

OBJECTIVESnWe analyzed the antiplatelet effects of different P2Y(12) receptor blockers with VerifyNow P2Y12 assay (VN-P2Y12) and light transmittance aggregometry (LTA).nnnBACKGROUNDnThe point-of-care VN-P2Y12 has been used to assess the antiplatelet effects in clopidogrel-treated patients but has not been evaluated in detail in patients treated with ticagrelor.nnnMETHODSnPatients were randomly assigned to either ticagrelor [180 mg loading/90 mg twice daily (n = 37)] or clopidogrel [600 mg loading/75 mg daily (n = 39)] on top of aspirin treatment, and platelet reactivity was measured serially during onset, maintenance, and offset phases. High on-treatment platelet reactivity (HPR) was defined as 5 and 20 μM adenosine diphosphate-induced maximal platelet aggregation ≥46% and ≥59%, respectively, and P2Y12 reaction units ≥235.nnnRESULTSnPlatelet function measured by VN-P2Y12 correlated well with LTA (.812 ≤ ρ ≤ .823, P < .001). VN-P2Y12 BASE values were consistent during administration of both agents. Calculated and reported percent inhibitions by VN-P2Y12 were similar (difference, -0.6%; 95% agreement limits, -22.9% to 21.6%). Platelet inhibition by VN-P2Y12 during clopidogrel and ticagrelor administrations was comparable to platelet inhibition by LTA. HPR determined by LTA and VN-P2Y12 were well matched, and the risk stratification between the two methods showed strong agreement after both therapies (κ > .7).nnnCONCLUSIONSnThe VerifyNow P2Y12 assay is effective in assessing the antiplatelet effects and in identifying HPR during clopidogrel or ticagrelor therapy.

Trends in the Incidence of Hospitalized Acute Myocardial Infarction and Stroke in Korea, 2006-2010

This study attempted to calculate and investigate the incidence of hospitalized acute myocardial infarction (AMI) and stroke in Korea. Using the National Health Insurance claim data, we investigated patients whose main diagnostic codes included AMI or stroke during 2006 to 2010. As a result, we found out that the number of AMI hospitalized patients had decreased since 2006 and amounted to 15,893 in 2010; and that the number of those with stroke had decreased since 2006 and amounted to 73,501 in 2010. The age-standardized incidence rate of hospitalized AMI, after adjustment for readmission, was 41.6 cases per 100,000-population in 2006, and had decreased to 29.4 cases in 2010 (for trend P < 0.001). In the case of stroke was estimated at 172.8 cases per 100,000-population in 2006, and had decreased to 135.1 cases in 2010 (for trend P < 0.001). In conclusion, the age-standardized incidence rates of both hospitalized AMI and stroke in Korea had decreased continuously during 2006 to 2010. We consider this decreasing trend due to the active use of pharmaceuticals, early vascular intervention, and the national cardio-cerebrovascular disease care project as the primary and secondary prevention efforts.

Prevalence and Related Factors for High-Risk of Obstructive Sleep Apnea in a Large Korean Population: Results of a Questionnaire-Based Study

Background and Purpose A population-based door-to-door study of cross-sectional methods for assessing the prevalence and factors related to a high risk of obstructive sleep apnea (OSA) was conducted using the Korean version of the Berlin Questionnaire (K-BQ). Methods Pooled data collected from Community Health Surveys by the Korea Center for Disease Control and Prevention were analyzed. Of 8,140 respondents from the population, 7,955 were finally included in this study. Results Of the 7,955 included subjects, 15.7% of the men and 9.8% of the women were at high risk of OSA. Significant differences were found in the following factors between the subjects with a high risk of OSA: gender, age, marital status, educational level, occupation, and presence of smoking, harmful alcohol use, and chronic diseases. Male sex, harmful alcohol use, and the presence of chronic diseases were identified as factors independently associated with a high risk of OSA. Conclusions This is the first study to confirm the usefulness of the K-BQ to study the prevalence of OSA in the Korean general population. The findings demonstrate that harmful alcohol use and chronic diseases are very common characteristics among those with a high risk of OSA.

The Influence of Individual-Level Social Capital on Depression

Objectives: This study was performed to investigate the relationship between individual-level social capital and depression. Methods: Data from the 2009 Community Health Survey were analyzed for this study. We used chi-square tests and hierarchical logistic regression analyses to determine the relationship between individual-level social capital and depression. The Korean version of the Center for Epidemiological Studies-Depression Scale was used to measure depression. Results: After controlling for socio-demographic factors such as, health behavior and chronic illness morbidity, that are associated with individual-level social capital, trust and informal participation significantly affected depression. Respondents with be trust(0.536, 95% CI 0.419-0.685) and who participate in informal groups(0.657, 95% CI 0.516-0.836) had significantly lower odds ratios of depression. Conclusions: Considering and introducing measures to increase the social capital of residents, need reduce depression. It is especially necessary to enhance resident empowerment.

Applications of the Participatory Learning Process in Health Promotion

Objectives: This study was conducted to develop a participatory learning process and apply it to community empowerment for health promotion. Methods: The participatory learning sessions were composed of three stages according to the modified Freirean model of empowerment education. Stage 1 of generating themes (listening stage) was replaced with a community health forum. Stage 2 of problem-posing was executed via a two-session small group brainstorming discussion for selecting priority community health problems and strategies to solve them. Stage 3 of act-reflect-act, the implementation of the chosen strategies, is ongoing. We tested the feasibility of the participatory learning processes in the pilot programs for health education. Then, 14 Myeon (or Dong) Health Committee members used them in Health Plus Happiness Plus projects for community empowerment to achieve health equity in Gyeongsangnam-Do, Korea. Results: In the pilot program for feasibility, more than 80% of the 95 participants gave positive responses to evaluation questionnaires after three or four participatory learning sessions. Health Committee members successfully selected various strategies relevant to their communities with facilitation, but without any teaching from outside professionals. Conclusions: We successfully applied the participatory learning process to health promotion. However, more studies are warranted to evaluate its long-term applicability.

Novel role of platelet reactivity in adverse left ventricular remodelling after ST-segment elevation myocardial infarction: The REMODELING Trial

The role of platelet-leukocyte interaction in the infarct myocardium still remains unveiled. We aimed to determine the linkage of platelet activation to post-infarct left ventricular remodelling (LVR) process. REMODELING was a prospective, observational, cohort trial including patients (n = 150) with ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention. Patients were given aspirin plus clopidogrel therapy (600 mg loading and 75 mg daily). Platelet reactivity (PRU: P2Y12 Reaction Units) was assessed with VerifyNow P2Y12 assay on admission. Transthoracic echocardiography was performed on admission and at one-month follow-up. The primary endpoint was the incidence of LVR according to PRU-based quartile distribution. LVR was defined as a relative ≥ 20u2009% increase in LV end-diastolic volume (LVEDV) between measurements. Adverse LVR was observed in 36 patients (24.0u2009%). According to PRU quartile, LVR rate was 10.8u2009% in the first, 23.1u2009% in the second, 27.0u2009% in the third, and 35.1u2009% in the fourth (p = 0.015): the optimal cut-off of PRU was ≥ 248 (area under curve: 0.643; 95u2009% confidence interval: 0.543 to 0.744; p = 0.010). LVR rate also increased proportionally according to the level of high sensitivity-C reactive protein (hs-CRP) (p = 0.012). In multivariate analysis, the combination of PRU (≥ 248) and hs-CRP (≥ 1.4 mg/l) significantly increased the predictive value for LVR occurrence by about 21-fold. In conclusion, enhanced levels of platelet activation and inflammation determined the incidence of adverse LVR after STEMI. Combining the measurements of these risk factors increased risk discrimination of LVR. The role of intensified antiplatelet or anti-inflammatory therapy in post-infarct LVR process deserves further study.

Elderly Peritoneal Dialysis Compared with Elderly Hemodialysis Patients and Younger Peritoneal Dialysis Patients: Competing Risk Analysis of a Korean Prospective Cohort Study

The outcomes of peritoneal dialysis (PD) in elderly patients have not been thoroughly investigated. We aimed to investigate the clinical outcomes and risk factors associated with PD in elderly patients. We conducted a prospective observational nationwide adult end-stage renal disease (ESRD) cohort study in Korea from August 2008 to March 2013. Among incident patients (n = 830), patient and technical survival rate, quality of life, and Beck’s Depression Inventory (BDI) scores of elderly PD patients (≥65 years, n = 95) were compared with those of PD patients aged ≤49 years (n = 205) and 50~64 years (n = 192); and elderly hemodialysis (HD) patients (n = 315). The patient death and technical failure were analyzed by cumulative incidence function. Competing risk regressions were used to assess the risk factors for survival. The patient survival rate of elderly PD patients was inferior to that of younger PD patients (P<0.001). However, the technical survival rate was similar (P = 0.097). Compared with elderly HD patients, the patient survival rate did not differ according to dialysis modality (P = 0.987). Elderly PD patients showed significant improvement in the BDI scores, as compared with the PD patients aged ≤49 years (P = 0.003). Low albumin, diabetes and low residual renal function were significant risk factors for the PD patient survival; and peritonitis was a significant risk factor for technical survival. Furthermore, low albumin and hospitalization were significant risk factors of patient survival among the elderly. The overall outcomes were similar between elderly PD and HD patients. PD showed the benefit in BDI and quality of life in the elderly. Additionally, the technical survival rate of elderly PD patients was similar to that of younger PD patients. Taken together, PD may be a comparable modality for elderly ESRD patients.

The Association of Social Support and Quality of Life of Stroke Patients in a City

: Among social support, satisfaction of dependable when you need help is the highest score(5.3) and console you when you are very upset is the lowest(4.0). Vitality among health related quality of life(HRQOL) is the higest score(55.9) and general health score is the the lowest(17.4). Physical component score(PCS) is lower than mental component. The results of multiple regression analysis about the factors affecting the PCS and MCS score, disability grade and feel better variable gave effect HRQOL.

Medication nonadherence in Korean patients with rheumatoid arthritis: the importance of beliefabout medication and illness perception

Background/Aims To investigate medication nonadherence in Korean patients with rheumatoid arthritis (RA) and analyze related factors. Methods A total of 292 patients with RA participated in this study. Medication nonadherence, intentional or unintentional, was gauged via self-reported questionnaire. Patient perceptions of illness, treatment beliefs, and moods were measured via Brief Illness Perception Questionnaire, Beliefs about Medicines Questionnaire, and Patient Health Questionnaire-2, respectively. Demographic and clinical data were also collected. Multinomial regression analysis was used to assess the impact of demographic, clinical, and psychological factors on medication nonadherence. Results The medication nonadherence rate was 54.1% (intentional, 21.6%; unintentional, 32.5%). Intentional nonadherence was reported most often in patients treated daily drugs (nonsteroidal anti-inflammatory drugs and/or disease-modifying antirheumatic drugs) (24.2%), and unintentional nonadherence was highest in patients receiving methotrexate (33.3%) (p = 0.872). In univariate analysis, beliefs in necessity and concerns of medication differed significantly in adherent and nonadherent patients (intentional or unintentional). When controlling for other factors that may impact medication nonadherence, less belief in necessity of medication (odds ratio [OR], 0.81; 95% confidence interval [CI], 0.68 to 0.95) and greater emotional response to disease (OR, 1.19; 95% CI, 1.01 to 1.40) were important predictors of intentional nonadherence. Conclusions Medication nonadherence is common in Korean patients with RA. Less belief in necessity of medication and greater emotional response to disease were identified as key factors prompting intentional nonadherence. These factors may be strategically targeted to improve medication adherence rates and subsequent clinical outcomes.

Mortality and cancer after 12 versus 30 months dual antiplatelet therapy: The Korean Outcomes Registry Evaluating Antithrombotics (KOREA)

The optimal duration and cancer risks of antiplatelet therapy following percutaneous coronary intervention (PCI) are unclear. We compared cancer and all-cause mortality after dual antiplatelet therapy (DAPT) for the combination of clopidogrel and aspirin (ASA) versus ASA alone over 18 months follow-up in event-free patients at 12 months DAPT from the Health Insurance Review and Assessment (HIRA) dataset via the Korean Outcomes Registry Evaluating Antithrombotics (KOREA). We selected PCI patients who were event free for 12 months and maintained a consistent antiplatelet regimen for 18 more months. The primary endpoints were any cancer and all-cause mortality at 30 months follow-up after PCI. From 320,351 screened post-PCI patient HIRA records, we excluded 294,413 and qualified 25,938, constituting DAPT (n=10,992) and ASA (n=14,946) groups. The Propensity Score Matching (PSM), and Inverse Probability of Treatment Weighting (IPTW) revealed no significant differences in background demographics and clinical characteristics for DAPT versus ASA patients. At 30-months post-PCI, after massive (>91u2009%) exclusions, cancer risk was higher for continuous DAPT [455 (4.15u2009%) vs 606 (4.04u2009%); HR=1.221; 95u2009%CI: 1.061-1.405; p=0.005], which remained significant by PSM (p=0.006) or IPTW (p=0.007), while all-cause mortality was similar [136 (1.24u2009%) vs 192 (1.28u2009%) HR=0.999; 95u2009%CI: 0.736-1.135; p=0.993]. This analysis suggests a potential mild excess cancer risk, but no mortality benefit in Korean post-PCI patients treated with DAPT for an additional 18 months beyond conventional 12 months DAPT. These data are not supporting continuing DAPT for more than one year in East Asians. Analysing cancer types and assessing potential cancer association with bleeding are warranted.