Jin-Won Kwon

Prevalence and risk factors of Helicobacter pylori infection in Korea: Nationwide multicenter study over 13 years

BackgroundThe aim of this study was to evaluate the time trend of seropositivity of Helicobacter pylori (H. pylori) over the period of 13 years in an asymptomatic Korean population, and investigate associated risk factors.MethodsThis cross-sectional nationwide multicentre study surveyed anti-H. pylori IgG antibodies in 19,272 health check-up subjects (aged [greater than and equal to]16 years) in 2011. Risk factors for H. pylori infection were investigated using logistic regression. Seropositivity in asymptomatic subjects without H. pylori eradication was compared between the years 1998 and 2005. Birth cohort effects were also evaluated.ResultsAfter exclusion of subjects with a history of H. pylori eradication therapy (n = 3,712, 19.3%) and gastric symptoms (n = 4,764, 24.7%), the seroprevalence of H. pylori infection was 54.4% in 10,796 subjects. This was significantly lower than the seroprevalence of 59.6% in 2005 and that of 66.9% in 1998, and this decrease of seropositivity of H. pylori became widespread across all ages and in most areas of the country. This decreasing trend could be explained by cohort analysis. All younger birth cohorts had a lower seroprevalence of H. pylori than older birth cohorts at the same age. Decreased seroprevalence within the same birth cohorts also accounted for this phenomenon. Clinical risk factors of H. pylori infection were higher cholesterol level ([greater than and equal to] 240 mg/dl) (OR = 1.33; 95% CI = 1.14-1.54), male gender, older age, low income, and residence in a rural area.ConclusionsA decreasing trend of H. pylori seroprevalence due to a birth cohort effect requires further studies on its related human host factors as well as socio-economic and hygienic factors. In addition, the relationship between H. pylori infection and high cholesterol level needs more investigation regarding underlying pathogenesis.

Phase II Clinical Trial of Paclitaxel Loaded Polymeric Micelle in Patients with Advanced Pancreatic Cancer

ABSTRACT Purpose: To determine in patients, with locally advanced or metastatic pancreatic cancer (APC), efficacy and safety of treatment with intravenous paclitaxel loaded polymeric micelle (GPM). Patients and methods: This was a multicenter, open-label Phase II study. Patients with APC, ECOG performance status ≤ 2, no prior chemotherapy and adequate organ function were treated with 3-hour GPM infusions every 3 weeks. Initial patients were treated with 435 mg/m2 (n = 11). The dose was reduced for subsequent patients to 350 or 300 mg/m2 (n = 45). Primary endpoint was time to tumor progression (TTP). Results: 56 patients were enrolled. Median TTP for patients treated with 300 or 350 mg/m2 doses was 3.2 months (95% CI, 2.6–4.2). Median progression free survival (PFS) was 2.8 months (95% CI, 1.4–4.0). Median overall survival (OS) was 6.5 months (95% CI, 5.1–7.9). Among patients treated with above doses of GPM, there was 1 complete remission (CR) and 2 partial remissions (PR) with an overall response rate (ORR) of 6.7%. Disease control rate (CR + PR + stable disease) was 60.0%. Most common grade 3 toxicities were: neutropenia (40.0%), fatigue (17.8%), infection, dehydration, neuropathy (each 13.3%), and abdominal pain (11.1%). Conclusions: Treatment of APC with GPM at a dose of 300 mg/m2 q 3 weeks was well tolerated and common toxicities were qualitatively similar to Cremophor-based paclitaxel. GPM monotherapy resulted in OS and other efficacy parameters preferable to that seen historically with gemcitabine. Future studies of GPM in combination with other agents for treatment of APC are warranted.

Endovascular coiling versus neurosurgical clipping in patients with unruptured intracranial aneurysm: a systematic review

BackgroundTo compare the effects of endovascular coiling and neurosurgical clipping in patients with unruptured intracranial aneurysm.MethodsSixteen electronic databases were searched for articles published between 1950 and July 2010 to compare clinical outcomes of clipping and coiling. Researchers reviewed all searched articles and extracted data independently. The quality of studies and evidence were evaluated using MINORS and GRADEprofiler, respectively. The odds ratio (OR) was calculated using the inverse variance meta-analysis method for each study outcome. To assess heterogeneity of ORs across cohorts, Cochran’s Q statistic and I2 were used.ResultsOf 4160 studies, 24 were identified (n  =  31865). Clipping resulted in significantly higher disability using the Glasgow Outcome Scale (OR, 2.38; 95% CI, 1.33–4.26) and Modified Rankin Scale (OR, 2.83; 95% CI, 1.42–5.63) when compared with coiling. ORs for complications were also higher with clipping (ORs for neurological and cardiac complications were 1.94 with a 95% confidence interval [CI] of 1.09–3.47 and 2.51 with a 95% CI of 1.15–5.50). Clipping resulted in significantly greater disability in the short term (≤6 m)(OR on the Glasgow Outcome Scale, 2.72; 95% CI, 1.16–6.34), but not in the long term (>6 m)(OR for Glasgow Outcome Scale, 2.12; 95% CI, 0.93–4.84).ConclusionsCoiling was a better procedure for treatment of unruptured intracranial aneurysm in terms of disability, complications, especially in the short term. Because of the limitations of the reviewed studies, further studies are required to support the present results.

Bariatric surgery versus conventional therapy in obese Korea patients: a multicenter retrospective cohort study

Purpose In Korea, the results of bariatric surgery have not been compared with those of nonsurgical treatment. The purpose of this study was to evaluate the effectiveness and safety of bariatric surgery vs. conventional nonsurgical treatment in severely obese Koreans. Methods In this retrospective cohort study, we reviewed the medical charts of 261 consecutive subjects who underwent bariatric surgery and 224 subjects who were treated with weight control medication and lifestyle modification therapy between January 2008 and February 2011. Measures of clinical effectiveness, including change in weight (%) and comorbid diseases, and occurrence of complications, were investigated for 18 months after bariatric surgery. Results Body mass index (BMI) was higher in the surgery group than in the conventionally treated group (mean ± standard deviation, 39.0 ± 6.2 vs. 34.3 ± 3.8). Diabetes was more prevalent in the surgery group than in the conventionally treated group (39.1% vs. 12.9%). The change in weight (%) between baseline and 18 months posttreatment was significantly greater in the surgery group (22.6%) than in the conventional therapy group (6.7%). While 57%, 47%, and 84% of subjects recovered from diabetes, hypertension, and dyslipidemia, respectively, in the surgery group, 10%, 20%, and 24% of subjects recovered from these conditions in the conventional group. Fifty-one subjects (19.5%) in the surgery group reported 61 complications (23.4%). Conclusion Bariatric surgery in Korea was significantly more effective than conventional treatment for weight loss and recovery from comorbidities such as diabetes, hypertension, and dyslipidemia, with a reasonable complication rate.

A Large National Cohort Study of the Association between Bisphosphonates and Osteonecrosis of the Jaw in Patients with Osteoporosis: A Nested Case-control Study

The purpose of this study was to examine the association between bisphosphonate exposure and osteonecrosis of the jaw (ONJ) in Korean patients with osteoporosis. A nested case-control study was performed using the claims database during 2002 to 2010 provided by the National Health Insurance Service. We identified a cohort of individuals with diagnosis of osteoporosis during 2002 to 2010. Cases and controls were identified during 2004 to 2010, and the date of potential cases of ONJ was defined as the index date. Bisphosphonate exposure was evaluated during 2 y prior to the index date. The association between bisphosphonate exposure and ONJ was tested by performing a conditional logistic regression analysis for matched data, and odds ratios (ORs) with 95% confidence intervals (CIs) were presented. Subjects were classified as nonuser, recent user, past user, or continuous user, depending on the prescription of bisphosphonates in 2 periods (1 to 2 y and 0 to 1 y prior to the index date). Continuous users were defined as patients who were exposed to bisphosphonate in both periods. We also examined the impact of bisphosphonate medication compliance by measuring the cumulative duration of exposure (CDE) on the risk of ONJ. A total of 212 cases with ONJ and 2,120 controls matched by sex, age, income level, and insurance type were identified among 109,787 patients with osteoporosis out of 1,025,340 enrollees in the sample cohort. The odds of having ONJ after adjusting for patient comorbidities significantly increased in continuous users of bisphosphonates (OR, 3.9; 95% CI, 2.4 to 6.2) compared to nonusers. Increased odds of ONJ were observed as CDE increased. The adjusted OR in patients with 1.5 y < CDE ≤ 2 y prior to the index date was 7.8 (95% CI, 4.0 to 15.5) versus nonusers. Our study results support significantly increased occurrences of potential ONJ in patients with osteoporosis who were exposed to bisphosphonates compared to those without exposure.

Rupture rate for patients with untreated unruptured intracranial aneurysms in South Korea during 2006–2009

OBJECT The authors investigated the rupture rate among patients with untreated unruptured intracranial aneurysms (UIAs) in South Korea during 2006-2009. METHODS A longitudinal study using national representative health-claim data, including all hospital records for every Korean citizen, was used. Patients with a UIA who were 18-80 years old in 2006 were identified using the I67.1 ICD-10 code. To select eligible patients, a historical period of 1 year prior to the first diagnosis of a UIA in 2006 was utilized. Patients with a previous UIA diagnosis, subarachnoid hemorrhage (SAH), or treatments, such as clipping or coiling, during the historical period were excluded from analysis. Patients with head trauma or a brain tumor during the historical period were also excluded. Eligible patients were followed up for at least 3 years from the index date. Rupture was defined as SAH events with at least 14 days of hospitalization, using the I60 ICD-10 code and excluding the I60.8 code, or death within 14 days of hospitalization. RESULTS Seven thousand four hundred four patients with UIAs were identified, including 1441 treated patients (20%) and 5963 untreated patients (80%), with a median follow-up of 3.3 years. Rupture events occurred in 163 (0.9 cases/100 person-years) of the 5963 untreated patients. The rupture rate was highest in the 1st year after UIA diagnosis. An older age was a risk factor for rupture among patients with UIAs. CONCLUSIONS The overview of the incidence of rupture indicates the need for a preventive strategy and future studies to prevent rupture in Asian patients with UIAs.

Cost Comparison between Surgical Treatments and Endoscopic Submucosal Dissection in Patients with Early Gastric Cancer in Korea

Background/Aims This study was conducted to evaluate whether medical costs can be reduced using endoscopic submucosal dissection (ESD) instead of conventional surgeries in patients with early gastric cancer (EGC). Methods Patients who underwent open gastrectomy (OG), laparoscopy-assisted gastrectomy (LAG), and ESD for EGC were recruited from three medical institutions in 2009. For macro-costing, the medical costs for each patient were derived from the expenses incurred during the patient’s hospital stay and 1-year follow-up. The overall costs in micro-costing were determined by multiplying the unit cost with the resources used during the patients’ hospitalization. Results A total of 194 patients were included in this study. The hospital stay for ESD was 5 to 8 days and was significantly shorter than the 12-day hospital stay for OG or the 11- to 17-day stay for LAG. Using macro-costing, the average medical costs for ESD during the hospital stay ranged from 2.1 to 3.4 million Korean Won (KRW) per patient, and the medical costs for conventional surgeries were estimated to be between 5.1 million and 8.2 million KRW. There were no significant differences in the 1-year follow-up costs between ESD and conventional surgeries. Conclusions ESD patients had lower medical costs than those patients who had conventional surgeries for EGC with conservative indications.

The Association between Polypharmacy and Dementia: A Nested Case-Control Study Based on a 12-Year Longitudinal Cohort Database in South Korea

Dementia is a major concern among growing chronic diseases in the aging society and its association with polypharmacy has not been adequately assessed. The objective of this study was to determine the association between polypharmacy and dementia through multiple statistical approaches. We conducted a nested case-control study for newly diagnosed dementia cases using the South Korean National Health Insurance Service sample cohort database (2002–2013, n = 1,025,340). Interactions between polypharmacy (an average use of ≥5 prescription drugs daily) and comorbidities or potentially inappropriate medications (PIMs) were tested. The odds ratios (ORs) for dementia were analyzed according to the presence of comorbidities, PIM uses, the average number of prescribed daily drugs, and significant interactions with polypharmacy using univariate and multiple logistic regression analyses. A higher prevalence of comorbidities, history of PIM use, higher PIM exposure, and higher proportion of polypharmacy were noted among cases than in controls. In the univariate analysis, the OR for dementia increased significantly with the increase in the number of prescribed drugs [1–<5 drugs: 1.72, 95% confidence interval (CI): 1.56–1.88; 5–<10 drugs: 2.64, 95% CI: 2.32–3.05; ≥10 drugs: 3.35, 95% CI: 2.38–4.71; <1 drug used as reference]. Polypharmacy was correlated with comorbidities and PIM use, and significant interactions were observed between polypharmacy and anticholinergics; H2-receptor antagonists; and comorbidities such as hypertension, peripheral or cerebrovascular disease, congestive heart failure, hemiplegia, diabetes, depression, all other mental disorders, chronic obstructive pulmonary disease, peptic ulcer disease, and chronic liver disease (p<0.001). In the multiple regression analysis, most cases exhibited increasing ORs for dementia with increasing polypharmacy levels. Moreover, the increase in OR was more evident in the absence of drugs or comorbidities that showed significant interactions with polypharmacy than in their presence. Polypharmacy increases the risk of PIM administration, and as some PIMs may have cognition-impairing effects, prolonged polypharmacy may result in dementia. Therefore, efforts are needed to limit or decrease the prescription of medications that have been associated with risk of dementia in the elderly.

The improvement of quality of life in patients treated with bariatric surgery in Korea.

Purpose Bariatric surgery is considered an efficient treatment for severe obesity, but postoperative complications and psychosocial problems may impact quality of life (QoL). Although QoL is an important aspect of bariatric surgery, few studies have evaluated the changes in QoL. We examined whether severely obese patients who had undergone bariatric surgery had better QoL compared with severely obese adults who had not undergone bariatric surgery in Korea. Methods Data were obtained from 78 participants in two groups; bariatric surgery group (n = 53) and nonsurgery group (n = 25). EuroQoL-5D (EQ-5D), the impact of weight on quality of life-lite (IWQoL-lite) and the obesity-related psychosocial problem scale (OP-scale) were used to assess the improvement of QoL. Results A total of 78 patients completed the QoL forms as part of their surgical consultation. In the EQ-5D, the changes of EQ-5D 3 level and EQ-5D visual analogue scale in the surgery group was 0.174 and 24.6 versus 0.017 and 17.8 in the nonsurgery group (P = 0.197 and P = 0.179). The changes of IWQoL-lite and OP-scale were significantly improved after bariatric surgery. In the IWQoL-lite, the mean changes in the surgery group was 33.4 versus 14.3 points in the nonsurgery group (P = 0.000). In the OP-scale, the mean changes in the surgery group patients scored 39.3 versus 9.0 points in the nonsurgery group (P = 0.000). Conclusion We demonstrated significant improvement of QoL observed after bariatric surgery compared to nonsurgical procedure. The results of this comparative study favor bariatric surgery for the treatment of severe obesity.

Gastroprotective effect of Cochinchina momordica seed extract in nonsteroidal anti-inflammatory drug-induced acute gastric damage in a rat model.

Background/Aims The major compounds of Cochinchina momordica seed extract (SK-MS10) include momordica saponins. We report that the gastroprotective effect of SK-MS10 in an ethanol-induced gastric damage rat model is mediated by suppressing proinflammatory cytokines and downregulating cytosolic phospholipase A2 (cPLA2), 5-lipoxygenase (5-LOX), and the activation of calcitonin gene-related peptide. In this study, we evaluated the gastroprotective effects of SK-MS10 in the nonsteroidal anti-inflammatory drug (NSAID)-induced gastric damage rat model. Methods The pretreatment effect of SK-MS10 was evaluated in the NSAID-induced gastric damage rat model using aspirin, indomethacin, and diclofenac in 7-week-old rats. Gastric damage was evaluated based on the gross ulcer index by gastroenterologists, and the damage area (%) was measured using the MetaMorph 7.0 video image analysis system. Myeloperoxidase (MPO) was measured by enzyme-linked immunosorbent assay, and Western blotting was used to analyze the levels of cyclooxygenase (COX)-1, COX-2, cPLA2, and 5-LOX. Results All NSAIDs induced gastric damage based on the gross ulcer index and damage area (p<0.05). Gastric damage was significantly attenuated by SK-MS10 pretreatment compared with NSAID treatment alone (p<0.05). The SK-MS10 pretreatment group exhibited lower MPO levels than the diclofenac group. The expression of cPLA2 and 5-LOX was decreased by SK-MS10 pretreatment in each of the three NSAID treatment groups. Conclusions SK-MS10 exhibited a gastroprotective effect against NSAID-induced acute gastric damage in rats. However, its protective mechanism may be different across the three types of NSAID-induced gastric damage models in rats.