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Purpose - Few studies investigated roles of body mass index (BMI) on gastric cancer (GC) risk according to Helicobacter pylori infection status. This study was conducted to evaluate associations between BMI and GC risk with consideration of H. pylori infection information. Materials and Methods - We performed a case-cohort study (n=2,458) that consists of a subcohort, (n=2,193 including 67 GC incident cases) randomly selected from the Korean Multicenter Cancer Cohort (KMCC) and 265 incident GC cases outside of the subcohort. H. pylori infection was assessed using an immunoblot assay. GC risk according to BMI was evaluated by calculating hazard ratios (HRs) and their 95% confidence intervals (95% CIs) using weighted Cox hazard regression model. Results - Increased GC risk in lower BMI group (< 23 kg/m2) with marginal significance, (HR, 1.32; 95% CI, 0.98 to 1.77) compared to the reference group (BMI of 23-24.9 kg/m2) was observed. In the H. pylori non-infection, both lower (< 23 kg/m2) and higher BMI (≥ 25 kg/m2) showed non-significantly increased GC risk (HR, 10.82; 95% CI, 1.25 to 93.60 and HR, 11.33; 95% CI, 1.13 to 113.66, respectively). However, these U-shaped associations between BMI and GC risk were not observed in the group who had ever been infected by H. pylori. Conclusion - This study suggests the U-shaped associations between BMI and GC risk, especially in subjects who had never been infected by H. pylori.

Background: The present study aimed to examine the association between cigarette smoking, alcohol consumption and colorectal cancer risk among Korean adults. Methods: Data from the Korean Multi-center Cancer Cohort between 1993 and 2005 were analyzed. The study population comprised 18,707 subjects aged older than 20 years old. The subjects were followed until December 31, 2011 (median follow-up of 11.2 years). The Cox proportional hazard model was used to estimate the hazard ratio (HR) and 95% confidence intervals of cigarette smoking and alcohol consumption for colorectal cancer risk. Results: In men, longer duration and higher average amount of alcohol consumption were associated with elevated risk of colorectal cancer (HR 1.93 [1.17–3.18] for ≥ 30 years of consumption compared to non-drinkers; HR 2.24 [1.31–3.84] for ≥ 30 g/d). Former smokers showed a non-significantly elevated risk of colorectal cancer in men. There was no apparent association between alcohol consumption or cigarette smoking and colorectal cancer risk among women. Conclusions: Alcohol consumption was associated with increased colorectal cancer risk among Korean men, and both a longer duration and a higher amount of consumption were associated with elevated risk.

Although there are lots of studies about the risk for the hepatitis B virus infection such as the residual risk for donated blood, there is no research on the risk of HBV infection, from the viewpoint of recipients in Korea. Using the data about HBsAg status of donated blood in 2008 and 2009, the distribution of blood components from the claim data of health insurance in 2009, the distribution of HBsAg and HBsAb of recipients, and some assumptions, we quantified the number of recipients in Korea that might be expected to receive HBV-contaminated blood components, as a proxy index for HBV infection by transfusion in 2009. Of the 376,211 recipients, the number who might be expected to receive blood components with HBV in 2009 was 23.2 (95 % CI 13.6, 36.8) in the basic model, 43.2 (95 % CI 25.4, 68.7) in extended model I, 55.2 (95 % CI 32.5, 87.7) in extended model II and 101.6 (95 % CI 59.8, 161.4) in extended model III. The number of HBV-positive samples per 100,000 transfused units was 0.6 in the basic model (95 % CI 0.3, 0.9), 1.1 in extended model I (95 % CI 0.6, 1.8), 1.4 in extended model II (95 % CI 0.8, 2.2), and 2.6 in extended model III (95 % CI 1.5, 4.1). This study showed that a few recipients might receive HBV-contaminated blood component by transfusion. These results could be used as a scientific evidence for health policy on HBV transfusion infection.

Previous cohort studies have demonstrated a positive association between diabetes mellitus (DM) and colorectal cancer (CRC). However, there are few comparisons between DM groups categorized by fasting glucose level. This study examined associations between diabetes as defined by fasting glucose level and self-reported history of DM and CRC risk among Korean adults. Data from the Korean Multi-center Cancer Cohort between 1993 and 2005 were analyzed. The study population comprised 14,570 participants aged 20 years or older. Participants were followed until December 31, 2012 (median follow-up: 11.9 years). Among participants with high fasting glucose (≥126mg/dL), the risk of developing CRC was significantly higher (HR: 1.51 [1.02-2.25]) than among participants with low fasting glucose (

Summary Background & aims To evaluate the relationship between phytoestrogen and colon cancer risk, we quantified plasma isoflavones (Genistein and Daidzein) and lignan (enterolactone) in a Korean nested case-control study and conducted replication study in a Vietnamese case-control study. Methods Study populations of 101 cases and 391 controls were selected from the Korean Multicenter Cancer Cohort which was constructed from 1993 to 2004. For replication study, Vietnamese hospital-based case-control subjects of 222 cases and 206 controls were selected from 2003 to 2007. The concentrations of plasma genistein, daidzein, and enterolactone were quantified by liquid chromatography-mass spectrometry. Logistic regression models were used to compute odds ratios (ORs) and 95% confidence intervals (CIs), and meta-analysis was conducted to estimate combined ORs (CORs) and 95% Cis of Korean and Vietnamese population in 2014. Results Genistein showed a continual decrease in colorectal cancer risk according to level up of the concentration categories in Korean and Vietnamese population ( P for trend = 0.032, and 0.001, respectively) and a significantly decreased risk was found at the highest concentration of genistein and daidzein (for the highest category compared to the lowest: COR (95% CI) = 0.46 (0.30–0.69), and COR (95% CI) = 0.54 (0.36–0.82)). When the study population was stratified, the beneficial relationship of genistein with colorectal cancer was observed regardless of sex and anatomical subtype. However, enterolacton level was not associated with colorectal cancer risk. Conclusions High plasma levels of isoflavones had relationship with a decreased risk of colorectal cancer, regardless of different ethnic background.

Objective The rates of participation in the Korean nationwide cervical cancer screening program and the rates of abnormal test results were determined. Methods The database of the National Health Insurance Service (NHIS) was used during the study period (2009–2014). Results The participation rate increased from 41.10% in 2009 to 51.52% in 2014 (annual percentage change, 4.126%; 95% confidence interval [CI]=2.253–6.034). During the study period, women ≥70 years of age had the lowest rate of participation (range, 21.7%–31.9%) and those 30–39 years of age the second-lowest (27.7%–44.9%). The participation rates of National Health Insurance beneficiaries (range, 48.6%–52.5%) were higher than those of Medical Aid Program (MAP) recipients (29.6%–33.2%). The rates of abnormal results were 0.65% in 2009 and 0.52% in 2014, with a decreasing tendency in all age groups except the youngest (30–39 years). Every year the abnormal result rates tended to decrease with age, from the age groups of 30–39 years to 60–69 years but increased in women ≥70 years of age. The ratio of patients with atypical squamous cells of undetermined significance compared with those with squamous intraepithelial lesions increased from 2.71 in 2009 to 4.91 in 2014. Conclusion Differences related to age and occurring over time were found in the rates of participation and abnormal results. Further efforts are needed to encourage participation in cervical cancer screening, especially for MAP recipients, elderly women and women 30–39 years of age. Quality control measures for cervical cancer screening programs should be enforced consistently.

Objectives Emerging evidence indicates that sleep duration is associated with health outcomes. However, the relationship of sleep duration with long-term health is unclear. This study was designed to determine the relationship of sleep duration with mortality as a parameter for long-term health in a large prospective cohort study in Korea. Methods The study population included 13 164 participants aged over 20 years from the Korean Multi-center Cancer Cohort study. Information on sleep duration was obtained through a structured questionnaire interview. The hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality were estimated using a Cox regression model. The non-linear relationship between sleep duration and mortality was examined non-parametrically using restricted cubic splines. Results The HRs for all-cause mortality showed a U-shape, with the lowest point at sleep duration of 7 to 8 hours. There was an increased risk of death among persons with sleep duration of ≤5 hours (HR, 1.21; 95% CI, 1.03 to 1.41) and of ≥10 hours (HR, 1.36; 95% CI, 1.07 to 1.72). In stratified analysis, this relationship of HR was seen in women and in participants aged ≥60 years. Risk of cardiovascular disease-specific mortality was associated with a sleep duration of ≤5 hours (HR, 1.40; 95% CI, 1.02 to 1.93). Risk of death from respiratory disease was associated with sleep duration at both extremes (≤5 and ≥10 hours). Conclusions Sleep durations of 7 to 8 hours may be recommended to the public for a general healthy lifestyle in Korea.

Background Gastric cancer, the most common cancer in the world, is affected by some foods or food groups. We examined the relationship between dietary intake and stomach cancer risk in the Korean Multi-Center Cancer Cohort (KMCC). Methods The KMCC included 19 688 Korean men and women who were enrolled from 1993 to 2004. Of those subjects, 9724 completed a brief 14-food frequency questionnaire at baseline. Through record linkage with the Korean Central Cancer Registry and National Death Certificate databases, we documented 166 gastric cancer cases as of December 31, 2008. Cox proportional hazard models were used to estimate relative risks (RRs) and 95% CIs. Results Frequent intake of soybean/tofu was significantly associated with reduced risk of gastric cancer, after adjustment for age, sex, cigarette smoking, body mass index, alcohol consumption, and area of residence (P for trend = 0.036). We found a significant inverse association between soybean/tofu intake and gastric cancer risk among women (RR = 0.41, 95% CI: 0.22–0.78). Men with a high soybean/tofu intake had a lower risk of gastric cancer, but the reduction was not statistically significant (RR = 0.77, 95% CI: 0.52–1.13). There was no interaction between soybean/tofu intake and cigarette smoking in relation to gastric cancer risk (P for interaction = 0.268). Conclusions Frequent soybean/tofu intake was associated with lower risk of gastric cancer.

BACKGROUND This study aimed at assessing the number of red blood cell (RBC) units transfused at different types of medical institution and examining the characteristics of transfusion recipients. METHODS We calculated and compared the number of transfusion recipients, total RBC units transfused, and RBC units transfused per recipient. Study data were extracted from insurance benefits reimbursement claims for RBC units at the Health Insurance Review & Assessment Service from 2006 to 2010. RESULTS Between 2006 and 2010, the number of recipients of RBC units increased from 298,049 to 376,445, the number of RBC units transfused increased from 1,460,799 to 1,841,695, and the number of RBC units transfused per recipient changed from 4.90 to 4.89. The number of recipients aged ≥65 yr increased from 133,833 (44.9%) in 2006 to 196,127 (52.1%) in 2010. The highest number of RBC units was transfused to patients with neoplastic diseases (31.9%) and diseases of the musculoskeletal system and connective tissue (14.4%). More than 80% of the total number of RBC units were transfused at tertiary and general hospitals. However, this composition rate was slightly decreasing, with the composition rate for hospitals increasing from 12.6% to 16.3%. CONCLUSIONS This study revealed an increase in the number of RBC units transfused over a 5-yr period due to an increase in the number of transfused recipients, especially recipients aged ≥65 yr; moreover, the number of RBC units transfused differed based on medical institution type. These results provide fundamental data on RBC transfusions required for future research.

Purpose: This research was done to identify the hospital arrival rate and factors related to prehospital delay in arriving at an emergency medical center within the golden time after symptom onset in patients with acute myocardial infarction (AMI). Methods: Data used in the research was from the National Emergency Department Information System of the National Emergency Medical Center which reported that in 2014, 9,611 patients went to emergency medical centers for acute myocardial infarction. Prehospital time is the time from onset to arrival at an emergency medical center and is analyzed by subdividing arrival and delay based on golden time of 2 hour. Results: After onset of acute myocardial infarction, arrival rate to emergency medical centers within the golden time was 44.0%(4,233), and factors related to prehospital delay were gender, age, region of residence, symptoms, path to hospital visit, and method of transportation. Conclusion: Results of this study show that in 2014 more than half of AMI patients arrive at emergency medical centers after the golden time for proper treatment of AMI. In order to reduce prehospital delay, new policy that reflects factors influencing prehospital delay should be developed. Especially, public campaigns and education to provide information on AMI initial symptoms and to enhance utilizing EMS to get to the emergency medical center driectly should be implemented for patients and/or caregivers.

To evaluate the association between smoking and physician-diagnosed stroke and myocardial infarction, this study used Community Health Survey data from 2009 on 92,082 males over the age of 30 years. Using multiple logistic regression, association index between smoking and physician-diagnosed stroke and myocardial infarction was calculated after adjusting the effects of age, hypertension, and diabetes. The odds ratios (95% confidence interval) of the physician-diagnosed stroke and myocardial infarction in the smoking group were 1.12 (1.02-1.24) and 1.21 (1.06-1.38) compared to the non-smoking group. The values of the physician-diagnosed stroke and myocardial infarction were 0.84 (0.74-0.94) and 0.96 (0.82-1.12) in the current-smoking subgroup, 1.38 (1.24-1.53) and 1.45 (1.26-1.67) in the ex-smoking subgroup, 1.39 (1.18-1.63) and 1.85 (1.53-2.24) in the 10- to 19-year smokers groups, 1.39 (1.22-1.58) and 1.36 (1.15-1.60) in the 30- to 40-year smokers groups, and 0.53 (0.44-0.63) and 0.47 (0.36-0.63) in those who had smoked for over 50 years. These results showed smoking was a risk factor for stroke and myocardial infarction in Korean males. This objective evidence should guide policy-making and public health interventions in the fields of smoking prevention and prohibition.

OBJECTIVES Diabetes and obesity each increases mortality, but recent papers have shown that lean Asian persons were at greater risk for mortality than were obese persons. The objective of this study is to determine whether an interaction exists between body mass index (BMI) and diabetes, which can modify the risk of death by cardiovascular disease (CVD). METHODS Subjects who were over 20 years of age, and who had information regarding BMI, past history of diabetes, and fasting blood glucose levels (n=16 048), were selected from the Korea Multi-center Cancer Cohort study participants. By 2008, a total of 1290 participants had died; 251 and 155 had died of CVD and stroke, respectively. The hazard for deaths was calculated with hazard ratio (HR) and 95% confidence interval (95% CI) by Cox proportional hazard model. RESULTS Compared with the normal population, patients with diabetes were at higher risk for CVD and stroke deaths (HR, 1.84; 95% CI, 1.33 to 2.56; HR, 1.82; 95% CI, 1.20 to 2.76; respectively). Relative to subjects with no diabetes and normal BMI (21 to 22.9 kg/m(2)), lean subjects with diabetes (BMI

This study was conducted to evaluate the relevance of the soluble form of c-Met protein, a truncated form of the c-Met membrane receptor involved in the CagA pathway, as a potential biomarker for gastric cancer. Among 290 gastric cancer case-control sets selected from the Korean Multicenter Cancer Cohort, the plasma concentrations of soluble c-Met protein were measured with enzyme-linked immunosorbent assays. Using analysis of variance and covariance models with age, sex, smoking, Helicobacter pylori infection, and CagA seropositivity, the mean concentrations of soluble c-Met protein between cases and controls were compared. To evaluate the association between gastric cancer and a c-Met protein level, odds ratios and 95% confidence intervals were estimated using conditional logistic regression models. Interactions between CagA-related genes and the soluble c-Met protein concentration were also investigated. The overall median plasma concentration of soluble c-Met among cases was significantly lower than those of controls (1.390 vs. 1.610 ng/mL, p < 0.0001). Closer to the onset of gastric cancer, the soluble c-Met protein level decreased linearly in a time-dependent manner (p for trend = 0.0002). The combined effects between the CagA-related genes and the soluble c-Met protein concentration significantly intensified risks for gastric cancer. Restricted analyses including cases that had been diagnosed within 1 year after entering the cohort had a fair degree of ability (area under the receiver operating characteristic curve of 0.73-0.77) to discriminate gastric cancer cases from normal controls. Our findings demonstrate the potential of the soluble form of c-Met protein as a novel biomarker for gastric cancer. The beneficial effects of a high soluble c-Met concentration in human plasma are strongly supported.

Objectives: To examine the association between alcohol consumption habit, types of beverages, alcohol consumption quantity, and overall and cancer-specific mortality among Korean adults. Methods: The alcohol consumption information of a total of 16 320 participants who were 20 years or older from the Korean Multicenter Cancer Cohort were analyzed to examine the association between alcohol consumption habit and mortality (median follow-up of 9.3 years). The Cox proportional hazard model was used to estimate the hazard ratio (HR) of alcohol consumption to mortality adjusting for age, sex, geographic areas, education, smoking status, and body mass index. Results: Alcohol drinkers showed an increased risk for total mortality compared with never drinkers (HR, 1.72; 95% confidence interval [CI], 1.38 to 2.14 for past drinkers; HR, 1.21; 95% CI, 1.06 to 1.39 for current drinkers), while past drinkers only were associated with higher risk for cancer deaths (HR, 1.84; 95% CI, 1.34 to 2.53). The quantity of alcohol consumed per week showed a J-shaped association with risk of mortality. Relative to light drinkers (0.01 to 90 g/wk), never drinkers and heavy drinkers (>504 g/wk) had an increased risk for all-cause and cancer deaths: (HR, 1.18; 95% CI, 0.96 to 1.45) and (HR, 1.39; 95% CI, 1.05 to 1.83) for all-cause mortality; and (HR, 1.55; 95% CI, 1.15 to 2.11) and (HR, 2.07; 95% CI, 1.39 to 3.09) for all cancer mortality, respectively. Heavy drinkers (>504 g/wk) showed an elevated risk for death from stomach and liver cancers. Conclusions: The present study supports the existence of a J-shaped association between alcohol consumption quantity and the risk of all-cause and cancer deaths. Heavy drinkers had an increased risk of death from cancer overall and liver and stomach cancer.

summary Purpose: Longitudinal changes in the prevalence of self-reported physician-diagnosed allergic rhinitis (AR) in Korea and the association between the prevalence of AR and type of residence area among Korean males and females in 1998, 2001, 2005 and 2007e2009 were evaluated. Methods: Age-standardized prevalence was calculated using the Korea National Health and Nutrition Examination Survey (KNHANES) IeIV. Stratified factors of sex, age, and socioeconomic status were adjusted to compare the prevalence of AR in relation to residential area by multiple logistic analysis. Results: The prevalence of AR increased by tenfolds from 1.2 % in 1998 to 12.0 % in 2007e2009. The trends for prevalence of AR were also statistically significant (p < .05). The age-standardized prevalence of AR among urban females was higher (13.9%) than that in rural females (11.5%). After adjustment for survey years, age, socioeconomic levels and asthma, the odds of AR were higher in urban than rural residents, except for males in 1998. Conclusion: The prevalence of AR in Korea has increased over the past decade, and living in an urban area may be a susceptible factor. For prevention and management of AR, further evaluations of contributing factors and mechanisms underlying differences in AR are needed.

Aim: Screening algorithms for chronic kidney disease have been developed and validated in American populations. Given the worldwide burden of kidney disease, developing algorithms for populations outside the USA is needed. Methods: Using simple, non-invasive questions, we developed a prediction model for chronic kidney disease from national population samples in Korea. The Korean National Health and Nutrition Examination Survey (n = 6565) was used for model development while validation was performed in two independent population samples, internal (n = 2921) and external datasets (n = 8166). Chronic kidney disease was defined as glomerular filtration rate

Objectives: The purpose of this study was to identify the prevalence of and risk factors for urinary incontinence (UI) in Korean men. Methods: This epidemiologic survey adopted a two-stage systematic sampling method. A total of 5831 men participated in this survey. Face-to-face interviews were used to collect data. Age, mobility, self-care ability, comorbidities and smoking were included as potential risk factors. The type of UI was assessed with the Urogenital Distress Inventory-6 questionnaire. To provide representative population prevalence estimates, the sample population was weighted by age. Results: The age-adjusted prevalence of Korean male UI was 5.5%. Urgency urinary incontinence was the most prevalent incontinence type. Men aged 65 years and older had a rate of UI eight times that of men aged 19–44 years. Men with problems in mobility or self-care had an OR of 2.3 and 1.7, respectively. Conclusion: The age-adjusted prevalence of UI in community-dwelling Korean men was 5.5%, which is lower than that of Korean women and higher than previously reported prevalence of Korean male incontinence. Age, immobility, and self-care ability were risk factors for male UI.

Background Hepatitis B remains the most common transfusion-transmitted viral infection. We explored the current status of pre-transfusion screening and post-transfusion follow-up testing for hepatitis B virus (HBV) surface antigen (HBsAg) and antibodies (anti-HBs) in blood recipients from an area of high HBV endemicity. Methods A total of 7,780 blood recipients were transfused with at least 1 unit of blood component at a single university hospital in Korea between January 2006 and December 2009. Their medical records were reviewed, and their demographic and transfusion-related data were analyzed. Results Pre-transfusion HBsAg and anti-HBs levels were tested in 77.6% (6,037/7,780) of the recipients. The results varied widely according to recipient age. In all, 32.8% (1,982/6,037) of the recipients who were tested had dual negative pre-transfusion results for HBsAg and anti-HBs and, therefore, were at increased risk of HBV transmission. Post-transfusion follow-up testing for HBsAg and/or anti-HBs was performed in 22% (436/1,982) of the increased-risk group. Conclusions Our data show that current transfusion-related laboratory testing practice is not sufficient to properly investigate possible post-transfusion infections. Routine laboratory tests, including HBsAg and anti-HBs, should be recommended in transfusion guidelines.

Background: The role of soybean products in gastric cancer risk is not clear in epidemiologic studies due to measurement error from dietary intake questionnaires and due to different degrees of bias according to study design. To examine the association between soybean products and gastric cancer risk, we measured phytoestrogen biological markers in a nested case-control study. Methods: The study population was composed of 131 cases and 393 matched controls within the Korean Multicenter Cancer Cohort. The concentrations of the four biomarkers in the plasma samples were measured using time-resolved fluoroimmunoassay. Conditional and unconditional logistic regression models were used to compute the odds ratio (OR) and 95% confidence intervals (CI). Results: Median plasma concentrations of genistein (229 nmol/L for controls, 181.8 nmol/L for cases; P = 0.07) and daidzein (131.2 nmol/L for controls, 80.5 nmol/L for cases; P = 0.04) in cases were lower than in controls, whereas equol concentrations were similar. Compared with the reference group, gastric cancer risk decreased in the highest groups for genistein (OR, 0.54; 95% CI, 0.31-0.93) and daidzein (OR, 0.21; 95% CI, 0.08-0.58). Higher equol concentrations were associated with a decreased risk for gastric cancer (OR, 0.50; 95% CI, 0.27-0.90). The combination of the highest concentrations for each isoflavone category was associated with a 0.09-fold decreased risk for gastric cancer compared with the combination of the lowest concentrations for each category. There was no association between plasma lignan concentrations and gastric cancer. Conclusions: High serum concentrations of isoflavones were associated with a decreased risk for gastric cancer. Impact: These results suggest a beneficial effect of high soybean product intake for gastric cancer risk. Cancer Epidemiol Biomarkers Prev; 19(5); 1292–300. ©2010 AACR.

The aim of this study was to investigate the role of the estrogen receptor 1 (ESR1) genetic polymorphisms for early menopause that was classified as premature ovarian failure (POF) and early menopause (EM) and to examine whether the associations of ESR1 genetic variants are different for POF and EM.We selected 100 POF cases and matched 100 EM cases and 200 normal menopause (NM) controls from the Korean Multi-Center Cohort. Among them, we restricted idiopathic POF and EM cases vs NM controls by excluding POF/EM cases with medical/surgical causes. The XbaI (rs9340799) and PvuII (rs2234693) in the ESR1 gene were genotyped. The single-nucleotide polymorphism (SNP) and haplotype effects were analyzed by multivariate logistic regression and haplotype analysis. Also nominal polytomous logistic regression was used to find whether ESR1 genetic variants are differently associated with POF and EM.The global p values for idiopathic POF and EM were 0.08 and 0.39 (SNP-based), and0.001 and 0.12 (haplotype-based), respectively. The XbaI genetic variant containing the X allele was marginally significantly associated with a reduced risk of idiopathic POF (OR = 0.6, 95% CI 0.3-1.0). The P-x haplotype and diplotypes significantly decreased the risk of idiopathic POF (OR = 0.5, 95% CI 0.2-0.9; OR = 0.4, 95% CI 0.2-0.9, respectively). In contrast from POF, the P-x haplotypes and diplotypes insignificantly increased the risk for both idiopathic EM (p(polytomous) = 0.009 for P-x haplotype; p(polytomous) = 0.02 for P-x diplotypes).Our results suggest that the ESR1 gene including PvuII and XbaI polymorphisms may modify the risk of idiopathic premature ovarian failure (POF) but not idiopathic early menopause (EM) risk.

In this study, our aim was to investigate the association of inflammation-related genetic polymorphisms and gastric cancer risk and to examine whether the combined effect of soybean product intake modified cancer risk. Eighty-four incident gastric cancer cases and 336 matched controls were selected from the Korean Multi-Center Cancer Cohort. We selected 14 single nucleotide polymorphisms (SNP) from 5 genes [interleukin (IL)-1beta, IL-2, IL-4, IL-8, and IL-10] and used unconditional logistic regression model to calculate the odds ratios (OR) and 95% CI adjusting for H. pylori seropositivity, smoking, age, sex, enrollment year, and residential area. The risk for gastric cancer in relation to genetic polymorphisms and haplotypes were assessed according to soybean product intake levels. Although no single SNP effect was found, the combined effect between IL-10 gene variants of -592 GG/GA, -819 TC/CC, or -1082 AG/GG and low intake of soybean products had an increased risk for gastric cancer compared with the group with no risk gene variants and a high intake of soybean products (OR [95% CI] = 2.82 [1.04-7.62], 2.75 [1.02-7.44], and 4.34 [1.51-12.5], respectively). Among the low-soybean product intake group, IL-10 CCG haplotype had an increased risk of gastric cancer (OR = 3.38 [1.40-8.13]) relative to the ATA haplotype. Our results suggest that the association between IL-10 genetic polymorphisms and gastric cancer risk was modified by soybean product intake.

The purpose of this study was to identify factors that could be used as standardized criteria for evaluating occupational diseases in initial assessments or requests for examination. Using 100 administrative litigation cases on the work-relatedness of cerebrovascular diseases (CVDs) by the Seoul Branch of the Korea Labor Welfare Corporation (KLWC) from 1997 to 2002, we estimated the relationship between the investigated variables and designation of the work-relatedness of the CVD. As for the age, the odds ratio of the acceptance rate of a case as work-related in subjects over 60 yr of age was 0.08 (95% CI, 0.01-0.75), which was compared to subjects under 30 yr of age. Regarding working hours, the odds ratio of the acceptance rate of a case as work-related in CVDs in those over 56 hr was 9.50 (95% CI, 1.92-47.10) when compared to those less than 56 hr. As for the benefit type, the odds ratio of the acceptance rate of a case as work-related in medical benefits was 5.74 (95% CI, 1.29-25.54), compared to survivor benefits. As for the criteria for defining situations as work overload, the odds ratio of the acceptance rate of a case as work-related in injured workers was 12.06 (95% CI, 3.12-46.62), compared to that in non-injured workers. Our findings show that the criteria for defining situations of work overload played an important role in assessing the work-relatedness of CVDs in administrative litigation, and it is necessary to make the scientific evidence on judgement of work-relatedness on overwork.

Background: Helicobacter pylori are major carcinogen of gastric cancer, but the associations among gastric cancer, H. pylori infection status, and alcohol consumption are not fully described. This study aimed to clarify how H. pylori infection status affects the association between alcohol consumption and gastric cancer risk. Methods: We selected 949 case–cohort participants from the 18 863 Korean Multi-center Cancer Cohort (KMCC) populations. Gastric cancer incidence inside and outside of the subcohort were 12 and 254 cases, respectively. Seropositivities for CagA, VacA, and H. pylori infection were determined by performing immunoblot assays. Weighted Cox regression models were used to calculate hazard ratios and 95% confidence intervals (CIs). Results: Relative to non-drinking, heavy drinking (X7 times a week), and binge drinking (X55 g alcohol intake per occasion) showed a 3.48-fold (95% CI, 1.13–10.73) and 3.27-fold (95% CI, 1.01–10.56) higher risk in subjects not previously infected by H. pylori. There was no significant association between drinking pattern and gastric cancer risk in H. pylori IgG seropositive subjects. An increased risk for gastric cancer in heavy- and binge-drinking subjects were also present in subjects not infected by CagA- or VacA-secreting H. pylori. Conclusions: Heavy and binge alcohol consumption is an important risk factor related to an increasing incidence of gastric cancer in a population not infected by H. pylori.

Background Combination therapy, which reduces the dosage intensity of the individual drugs while increasing their efficacy, is not a novel approach for the treatment of cancer. Methylsulfonylmethane (MSM) is an organic sulfur compound shown to act against tumor cells. Tamoxifen is a commercially available therapeutic agent for breast malignancies. Methods In the current study, we analyzed the combinatorial effect of MSM and tamoxifen on the suppression of ER-positive breast cancer xenograft growth and metastasis. Additionally, we also validated the molecular targets by which the drug combination regulated tumor growth and metastasis. Results We observed that the combination of MSM and tamoxifen regulated cell viability and migration in vitro. The intragastric administration of MSM and subcutaneous implantation of tamoxifen tablets led to tumor growth suppression and inhibition of the Janus kinase 2 (Jak2)/signal transducer and activator of transcription 5b (STAT5b) pathway. Our study also assessed the regulation of signaling molecules implicated in the growth, progression, differentiation, and migration of cancer cells, such as Jak2, STAT5b, insulin-like growth factor-1Rβ, and their phosphorylation status. Conclusions Study results indicated that this combination therapy inhibited tumor growth and metastasis. Therefore, this drug combination may have a synergistic and powerful anticancer effect against breast cancer. Electronic supplementary material The online version of this article (doi:10.1186/s12885-015-1445-0) contains supplementary material, which is available to authorized users.

The purpose of this study is to present the information on the duration of treatment and the cost of work-related low back pain. Using the compensation-database for 1997 work-related low back pain (n=9,277), this study estimated the duration of treatment, the cost of work-related low back pain, the relationship between them, and probability of being off treatment at different intervals. The mean and the median of the treatment duration are 252.6 days and 175 days. The mean and the median of the cost of total insurance benefit are 37,700,000 won and 14,400,000 won. The treatment duration of 51% of the study subjects was less than 6 months and their cost accounted for 10.2% of the total insurance benefit. The subjects who were treated more than 24 months were 5.8% but it accounted for 29.2% of the cost. It was found that approximately 50% of the subjects who will remain on treatment at the end of n months would be off treatment at the end of n+5 months. This study presents the point in time when the low back pain (LBP) workers need to prepare to return to work by forecasting their off-treatment period. From the treat duration and cost perspectives, this study may be utilized as evidence for active management of work-related LBP.

The purpose of this study was to investigate the effect of genetic polymorphism of cytochrome P450 2E1 (CYP2E1) and aldehyde dehydrogenase 2 (ALDH2) on the xylene metabolism.Among 247 workers, 116 were occupationally exposed to xylene and 131 were not. Workers exposed to xylene had different work such as spray, touch-up, mixassist, and pre-treat. Questionnaire variables were age, sex, use of personal protective equipment, smoking, previous night's drinking and work duration. The urinary methylhippuric acid was measured in the urine collected in the afternoon and corrected by urinary creatinine concentration. The genotypes of CYP2E1 and ALDH2 were investigated by using PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) methods with DNA extracted from venous blood.1. The urinary concentrations of o-, m-, and pmethylhippuric acid and total methylhippuric acid in the exposed group were significantly higher than those in the non-exposed group (plt; 0.001). 2. In multiple regression analysis, the urinary methylhippuric acid concentration was significantly influenced by exposure grade (Job-exposure matrixes), smoking, drug use and kind of protective equipment (plt; 0.1). 3. Genetic polymorphism of CYP2E1 and ALDH2 did not affect urinary methylhippuric acid level in the exposed group (pgt; 0.05).Exposure grade, smoking, drug use and kind of protective equipment affected urinary methylhippuric acid level, whereas genetic polymorphism of CYP2E1 and ALDH2 did not. However, further investigation for the effect of genetic polymorphism on the metabolism of xylene with a larger sample size is needed.

Self-reported cancer is a valuable epidemiological tool for identifying cases in cohort studies. The cost, time, and resources required, in addition to the efficiency in ascertaining cases, need to be considered when deciding between active and passive follow-up approaches. Because Korean families hold a family-centered approach when making decisions (1), it is not uncommon for patients to be unaware of their cancer diagnosis or status. A total of 20% of physicians and 33% of family members opposed patient notification of his or her disease status (2), and only 35% of Korean-Americans would tell a patient about a terminal prognosis (1). Because of these cultural differences and, thus, inaccuracies in self-reported information that arise, there is a need to examine the appropriateness of the active follow-up

In a nested-case control study of 100 cases of gastric cancer and 400 matched controls in relation to virulence factors of Helicobacter pylori in a Korean cohort, CagA seropositivity was significantly associated with a higher risk of gastric cancer among H. pylori-infected subjects (OR=3.57, 95% CI 1.05–12.14).

We conducted a pilot nested case-control study to prospectively evaluate the effects of polycyclic aromatic hydrocarbons (PAH) exposure, antioxidant capacity, and oxidative stress on lung carcinogenesis.Thirty-five patients with lung cancer and 140 age- and sex-matched controls were selected from a sub-cohort of the Korean Multi-center Cancer Cohort. PAH metabolites (1-hydroxypyrene and 2-naphthol), oxidative stress markers, and total antioxidant capacity (TAC) were assessed using urine samples collected at baseline.The levels of urinary PAH metabolites and oxidative stress were not different between cases and controls. Urinary 1-hydroxypyrene and 2-naphthol levels were significantly associated with urinary oxidative stress markers only in lung cancer cases. Individuals with low urinary TAC and high urinary oxidative stress levels had significantly higher risk of lung cancer compared to those with high urinary TAC and low urinary oxidative stress levels.Oxidative stress induced by PAH exposure and TAC may be important determinants for the susceptibility to lung cancer.

Purpose: As a follow-up for the validity study of Community Health Surveys (CHSs), the purpose of this study was to evaluate the factors affecting the accuracy of CHSs by investigating subjects’ characteristics. Materials and Methods: We used data from 11,217 participants (aged 19 years or older) who had participated in the CHS, conducted by a local government in 2008 and analyzed the variables affecting the sensitivity and specificity of hospitalization and outpatient visit. Results: Multivariate logistic regression analysis showed that, factors related with the sensitivity of hospitalization and outpatient visit questions were gender, age, marital status, chronic diseases, medical checkup, the subjective health status and necessary medical services. Factors related with the specificity were gender, marital status, educational background, chronic diseases, medical checkup, alcohol consumption, necessary medical services and sadness. Conclusion: This study revealed the subject-related factors associated with the validity of the CHS. Efforts to improve the sensitivity and the specificity from self-report questionnaires should consider how the characteristics of subjects may affect their responses.

BACKGROUND: This study was carried out to estimate the vaccination coverage, public perception, and preventive behaviors against pandemic influenza A (H1N1) and to understand the motivation and barriers to vaccination between high-risk and non-high-risk groups during the outbreak of pandemic influenza A (H1N1). METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional nationwide telephone survey of 1,650 community-dwelling Korean adults aged 19 years and older was conducted in the later stage of the 2009-2010 pandemic influenza A (H1N1) outbreak. The questionnaire identified the demographics, vaccination status of participants and all household members, barriers to non-vaccination, perceived threat, and preventive behaviors. In Korea, the overall rate of pandemic influenza vaccination coverage in the surveyed population was 15.5%; vaccination coverage in the high-risk group and non-high-risk group was 47.3% and 8.0%, respectively. In the high-risk group, the most important triggering event for vaccination was receiving a notice from a public health organization. In the non-high-risk group, vaccination was more strongly influenced by previous experience with influenza or mass media campaigns. In both groups, the most common reasons for not receiving vaccination was that their health was sufficient to forgo the vaccination, and lack of time. There was no significant difference in how either group perceived the threat or adopted preventive behavior. The predictive factors for pandemic influenza vaccination were being elderly (age ≥ 65 years), prior seasonal influenza vaccination, and chronic medical disease. CONCLUSIONS/SIGNIFICANCE: With the exception of vaccination coverage, the preventive behaviors of the high-risk group were not different from those of the non-high-risk group during the 2009-2010 pandemic. For future pandemic preparedness planning, it is crucial to reinforce preventive behaviors to avoid illness before vaccination and to increase vaccination coverage in the high-risk group.

Objectives: To examine the association between body mass index (BMI), physical activity and colorectal cancer risk among Korean adults. Methods: Data from the Korean Multi-center Cancer Cohort (KMCC) between 1993 and 2005 were analyzed. The study population comprised 12,379 subjects aged above 20 years old. The subjects were followed until December 31, 2011 (median follow-up of 10.1 years). Measured weight and height values was used to calculate BMI and self-reported total time spent for physical activity were used. The Cox proportional hazard model was used to estimate the hazard ratio (HR) and 95% confidence intervals (CI) of BMI and physical activity for colorectal cancer risk. Results: Men who did moderate physical activity showed a lower risk for colorectal cancer (HR 0.35, 95% CI: 0.19-0.65 for 30-419 minutes compared to who spend less than 30 minutes a week doing moderate activities). We did not find any association between the total time of vigorous activities and muscle-strengthening activities and colorectal cancer risk in both men and women. Men with BMI of 25 or higher showed an increased risk for colorectal cancer compared to men with BMI of 18.5 to 22.9 (HR 1.64, 95% CI 0.94-2.88 for 25.0-29.9 kg/m2; HR 1.64, 95% CI 0.94-2.88 for greater than 30.0 kg/m2). Conclusions: Moderate physical activities were associated with lower colorectal cancer risk among Korean men. Citation Format: Sooyoung Cho, Aesun Shin, Sue K. Park, Hai-Rim Shin, Soung-Hoon Chang, Keun-Young Yoo. Body mass index, physical activity and risk of colorectal cancer in the Korean Multi-center Cancer Cohort (KMCC). [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1734.

The study aimed to examine the association between genes encoding molecules in the ornithine decarboxylase (ODC)-polyamine pathway (ODC1, AMD1, NQO1, NOS2A, and OAZ2) and gastric cancer risk and whether the gene-phytoestrogen interaction modifies gastric cancer risk.Among 76 gastric cancer cases and their 1:4 matched controls within the Korean Multi-center Cancer Cohort, a total of 30 SNPs in five genes involved in the ODC pathway were primarily analyzed. The second-stage genotyping in 388 matched case-control sets was conducted to reevaluate the significant SNPs interacting with phytoestrogens during the primary analysis. The summary odds ratios (ORs) [95 % confidence intervals (CIs)] for gastric cancer were estimated. Interaction effects between the SNPs and plasma concentrations of phytoestrogens (genistein, daidzein, equol, and enterolactone) were evaluated.In the pooled analysis, NQO1 rs1800566 showed significant genetic effects on gastric cancer without heterogeneity [OR 0.83 (95 % CI 0.70-0.995)] and a greater decreased risk at high genistein/daidzein levels [OR 0.36 (95 % CI 0.15-0.90) and OR 0.26 (95 % CI 0.10-0.64), respectively; p interaction 0.05]. Risk alleles of AMD1 rs1279599, AMD1 rs7768897, and OAZ2 rs7403751 had a significant gene-phytoestrogen (genistein and daidzein) interaction effect to modify the development of gastric cancer. They had an increased gastric cancer risk at low isoflavone levels, but a decreased risk at high isoflavone levels (p interaction 0.01).Our findings suggest that common variants in the genes involved in the ODC pathway may contribute to the risk of gastric cancer possibly by modulating ODC polyamine biosynthesis or by interaction between isoflavones and NQO1, OAZ2, and AMD1.

Purpose: This study was done to investigate factors affecting preparation stage to quit smoking in men. Methods: Based on data from the Community Health Survey conducted in Chungbuk Province in 2008, we estimated rates and odds ratio (OR) of smoking cessation intention for 2,639 men who were current smokers. Multivariate logistic regression analyses were used to identify factors affecting preparation stage to quit smoking. Results: Among current male smokers, the rate of smoking cessation intention was 17.1%. The OR of factors affecting smoking cessation was as follows: Compared to men with middle school education, the OR for rate of smoking cessation intention in men with high school education was 1.47 (p=.018), and for college or higher, 1.55 (p=.017). Compared to being single, the OR for cohabitation after marriage was 1.61 (p=.011) and living alone after marriage, 2.23 (p=.005). The OR for attempt to quit smoking, exposure to secondhand smoke and participation in smoking education were 6.80 (p

Scope To investigate whether genes involved in AKT/nuclear factor kappa B signaling and/or gene–environment interactions between the genes and phytoestrogens may be susceptible factors for gastric cancer. Methods and results The representative single nucleotide polymorphisms (SNPs) identified during the primary analysis (screening a total of 622 SNPs within ± 5 kbp of the 51 target gene locations) were further investigated in 317 matched case–control sets. The summary odds ratios (ORs) and 95% confidence intervals (CIs) for gastric cancer were calculated. Interaction effects between the SNPs and phytoestrogen biomarkers (genistein, daidzein, equol, and enterolactone) were computed. CDK1 rs4145643, FAS rs6586161, and FAS rs1468063 in the AKT signaling pathway presented significant genetic effects on gastric cancer (OR = 0.81 (95% CI: 0.66–0.99) for CDK1 rs4145643; OR = 1.27 (95% CI: 1.03–1.58) for FAS rs6586161; OR = 1.29 (95% CI: 1.03–1.56) for FAS rs1468063; Cochran Q statistics > 0.10). Risk alleles of FAS rs6586161, FAS rs1468063, MAP3K1 rs16886448, and MAP3K1 rs252902 showed significant interaction effects with enterolactone (pinteraction < 0.05). Conclusion CDK1 and FAS genes involved in AKT signaling and influenced by anti-carcinogenic property of phytoestrogens can play a role as susceptible genetic factors in gastric carcinogenesis. FAS and MAP3K1 genes significantly interact with enterolactone, thereby modifying the individual's risk for gastric cancer.

Screening algorithms for chronic kidney disease have been developed and validated in American populations. Given the worldwide burden of kidney disease, developing algorithms for populations outside the USA is needed.Using simple, non-invasive questions, we developed a prediction model for chronic kidney disease from national population samples in Korea. The Korean National Health and Nutrition Examination Survey (n = 6565) was used for model development while validation was performed in two independent population samples, internal (n = 2921) and external datasets (n = 8166). Chronic kidney disease was defined as glomerular filtration rate60 mL/min per 1.73 m(2).Seven factors - age, female gender, anaemia, hypertension, diabetes mellitus, cardiovascular disease and proteinuria - were significantly associated with prevalent chronic kidney disease. Integer scores were assigned to variables based on the magnitude of associations: 2 for age 50-59 years, 3 for age 60-69 years and 4 for age 70 years or older, and 1 for female gender, anaemia, hypertension, diabetes, proteinuria and cardiovascular dis ase. Based on the Youden index, a value of 4 or greater defined a high risk population with sensitivity 89%, specificity 71%, and positive predictive value 19%, and negative predictive value 99%. The area under the curve was 0.83 for the development set, and 0.87 and 0.78 in the two validation datasets.This prediction algorithm, weighted towards common non-invasive variables, had good performance characteristics in an Asian population, and provides new evidence of the similarity of the algorithms for Western and Eastern populations.

OBJECTIVES: To evaluate whether genes that encode CagA-interacting molecules (SRC, PTPN11, CRK, CRKL, CSK, c-MET and GRB2) are associated with gastric cancer risk and whether an interaction between these genes and phytoestrogens modify gastric cancer risk. METHODS: In the discovery phase, 137 candidate SNPs in seven genes were analyzed in 76 incident gastric cancer cases and 322 matched controls from the Korean Multi-Center Cancer Cohort. Five significant SNPs in three genes (SRC, c-MET and CRK) were re-evaluated in 386 cases and 348 controls in the extension phase. Odds ratios (ORs) for gastric cancer risk were estimated adjusted for age, smoking, H. pylori seropositivity and CagA strain positivity. Summarized ORs in the total study population (462 cases and 670 controls) were presented using pooled- and meta-analysis. Plasma concentrations of phytoestrogens (genistein, daidzein, equol and enterolactone) were measured using the time-resolved fluoroimmunoassay. RESULTS: SRC rs6122566, rs6124914, c-MET rs41739, and CRK rs7208768 showed significant genetic effects for gastric cancer in both the pooled and meta-analysis without heterogeneity (pooled OR = 3.96 [95% CI 2.05-7.65], 1.24 [95% CI = 1.01-1.53], 1.19 [95% CI = 1.01-1.41], and 1.37 [95% CI = 1.15-1.62], respectively; meta OR = 4.59 [95% CI 2.74-7.70], 1.36 [95% CI = 1.09-1.70], 1.20 [95% CI = 1.00-1.44], and 1.32 [95% CI = 1.10-1.57], respectively). Risk allele of CRK rs7208768 had a significantly increased risk for gastric cancer at low phytoestrogen levels (p interaction

BACKGROUND: CagA cellular interaction via activation of the ERK signaling pathway may be a starting point in the development of gastric cancer. This study aimed to evaluate whether genes involved in ERK downstream signaling pathways activated by CagA are susceptible genetic markers for gastric cancer. METHODS: In the discovery phase, a total of 580 SNPs within +/-5 kbp of 30 candidate genes were genotyped to examine an association with gastric cancer risk in the Korean Multi-center Cancer Cohort (100 incident gastric cancer case-control sets). The most significant SNPs (raw or permutated p value

Objectives : To increase the booster vaccination rate, the Korean government legislated a measles vaccination for elementary school students in 2001, requiring parents to submit a certificate of vaccination upon the admission of the students to elementary school. The purpose of this study was to evaluate the validity of measles vaccination certificates which were issued to parents. Methods : Using questionnaire survey data of 890 general practitioners and 9,235 parents in 2005, we investigated the evidence for booster vaccination certificates of measles. Results : In the survey of general practitioners, 59.5% of the certificates depended on the medical records of clinic, 13.5% was immunization booklets, 23.7% was reimmunizations, 1.9% was confirmation of record of other clinics, and 1.4% was parents statements or requests without evidence. In the survey of parents, 36.2% of the certificates depended on the medical records of clinic, 43.4% was immunization booklets, 18.0% was reimmunizations, and 2.4% was parents statements or requests without evidence. Conclusions : Our findings show that a majority of the booster vaccination certificates of measles was issued on the basis of documented vaccinations and it means that the implementation of the law requiring the submission of elementary school students' vaccination certificates has been very successful in Korea.

We examined whether the strength of the association of cigarette smoking differs according to histological type and gender, and assessed other risk factors, in particular, tuberculosis. We recruited cases from the Korean Academy of Tuberculosis and Respiratory Diseases and controls from Chungju, a local site of the Korean Multi-Center Cancer Cohort. We matched one case to one control for females and two cases to one control for males according to age (≤44, 45–69, and ≥70 years old). We used unconditional logistic regression to calculate the odds ratio (OR) and 95% confidence interval (CI) to estimate lung cancer risk by histologic type for males and females separately. The OR (95% CI) of 40 or more pack-years smoked relative to never smokers was 6.78 (4.17–11.00), 3.49 (1.83–6.33), and 2.72 (1.57–4.72) for males, and 13.72 (3.23–58.18), 12.18 (3.12–47.57), and 7.11 (1.78–28.43) for females for squamous cell, adenocarcinoma, and small cell carcinoma, respectively. Among males, the respective OR (95% CI) for past and current history of lung tuberculosis was 3.21 (2.12–4.90), 2.69 (1.63–4.45), and 1.52 (0.83–2.78), and for females was 2.40 (1.30–4.42), 4.20 (2.75–6.39), and 1.37 (0.61–3.06). Our findings provide additional evidence that women are more susceptible to the carcinogenic effects of tobacco, smoking has a higher risk for squamous cell and small cell carcinoma than adenocarcinoma, and tuberculosis is a potential risk factor for certain lung cancer histologic types.

【Objectives : Gastric cancer is the most common incident cancer in Korea. Although Helicobacter pylori infection is the most important risk factor for the development of gastric cancer, cigarette smoking has also been suggested to play an important role in the development of gastric cancer. The objective of this study is to evaluate the relationship between cigarette smoking and gastric cancer risk in a Korean population. Methods : The study population consisted of 13,785 subjects who had been enrolled in the Korean Multi-Center Career Cohort between 1993 and 2002. As of December 2002, 139 incident gastric cancer cases were ascertained through the Korea Central Cancer Registry and the National Death Certificate Database. Relative risks (RR) and 95% confidence intervals (CI) for gastric cancer were estimated using Cox#s proportional hazard model adjusted for age, education, alcohol drinking status and history of gastritis or ulcer. Results : Significant dose-response relationships were observed between the duration of smoking and the risk of gastric cancer among the male subjects in comparison to non-smokers: men who smoked for 20-39 years had a 2.09-fold (95% CI 1.00-4.38) increase, and those who smoked for more than 40 years had a 3.13-fold (95% CI 1.59-6.17) increase in the risk of gastric cancer ( $P_{trend} ). Conclusions : This study suggests that a longer duration of cigarette smoking may increase the risk of gastric cancer development in a dose-response manner in Korean men. The association between smoking and gastric cancer risk in women should be verified in future studies with a larger number of cases.】

Objectives : The aim of this study was to evaluate the roles of cigarette smoking, alcohol consumption, tuberculosis, and their interactions in the risk of lung cancer in a Korean cohort. Methods : The study subjects comprised 13,150 males and females aged above 20 years old. During the follow up period from 1993 to 2002, 79 lung cancer cases were identified by the central cancer registry and the national death certificate database. Information on cigarette smoking, alcohol consumption and the history of physician-diagnosed tuberculosis was obtained by interview. Indirect chest X-ray findings were also evaluated to ascertain tuberculosis cases. Cox proportional hazard models were used to estimate relative risks (RR) and 95% confidence intervals (CI) after adjusting for age and gender. Results : Cigarette smoking was statistically significantly associated with an increased risk of lung cancer [for current smokers, RR = 2.33 (95% CI = 1.23 - 4.42) compared to non-smokers]. After further adjustment for cigarette smoking, both alcohol consumption and tuberculosis showed no statistically significant association with the risk of lung cancer [for current drinkers, RR = 0.80 (95% CI = 0.48 - 1.33) compared to non-drinkers] [for tuberculosis cases, RR = 1.17 (95% CI = 0.58 - 2.36) compared to non-cases]. There was no statistically significant interaction between cigarette smoking and alcohol consumption (p-interaction = 0.38), or cigarette smoking and tuberculosis (p-interaction = 0.74). Conclusions : Although cigarette smoking was confirmed as a risk factor of lung cancer in this cohort study, this study suggests that alcohol consumption and tuberculosis may not be associated with the risk of lung cancer.

We conducted this study to examine premenopausal risk factors associated with premature ovarian failure (POF) and early menopause (EM) among Korean women.A 73% of total women aged 30-69 at four districts in the KMCC (Korean Multi-center Cancer Cohort) was participated in this study during 2002-2003. We selected 137 POF and 281 EM cases who had menopause before age 40 and at age 40-44, respectively, and 1318 normal menopause (NM) controls that experienced menopause at age 45-60, and among them, selected idiopathic POF (n=84) and EM (n=261) after excluding surgical/medical menopause. We collected the information of premenopausal lifestyle and reproductive risk factors. Multivariate and polytomous logistic regression were used to estimate POF and EM risk and to differentiate POF and EM risk using ordinal and nominal scale.Cigarette smoking was associated with an increased risk of idiopathic POF (OR=1.82 [1.03-3.23]), whereas oral contraceptive use was associated with a reduced risk of natural EM (OR=0.62 [0.43-0.90]). Idiopathic POF risk by both factors differed from idiopathic EM risk (p-nominal0.05). Factors related to ovulation, such as later menarche, irregular menstruation and longer breast feeding cumulatively reduced the risk of natural EM and POF (p-ordinal0.05). In analysis including medical and surgical menopause, lung tuberculosis, hysterectomy, past cancers, and lower number of deliveries before menopause were associated with POF.Our findings indicate that etiology in POF development may partly differ from that in EM.

Diabetes has been reported as a risk factor for several cancers. However, the association between diabetes and gastric cancer has been inconsistent. The aim of this study was to evaluate the association between the fasting serum glucose level and gastric cancer risk in Korea.Among the members of the Korean MultiCenter Cancer Cohort (KMCC) from 1993 to 2004, a total of 100 incident gastric cancer cases were ascertained until December 31, 2002 and 400 controls were matched according to age, sex, and year and area of enrollment. Of the eligible subjects, those without fasting serum glucose level information were excluded, with a total of 64 cases and 236 controls finally selected. On enrollment, all subjects completed a baseline demographic and lifestyle characteristics questionnaire, and had their fasting serum glucose level measured. The Helicobacter pylori infection status was determined by an immunoblot assay using long-term stored serum. The odds ratios (ORs) were estimated using conditional and unconditional logistic regression models adjusted for the H. pylori infection status, smoking, drinking, education, follow-up period and matching variables.The ORs for risk of gastric cancer according to the serum glucose level were 1.33 [95% CI=0.50-3.53] and 1.66 [95% CI=0.55-5.02] for the categories of 100-125 and 126 mg/dL or greater, respectively, compared to the category of less than 100 mg/dL. No increased risk of gastric cancer according to the serum glucose level was found (p-trend=0.337).This study provides no evidence for an association of the serum glucose level with gastric cancer.