Association between Body Mass Index and Gastric Cancer Risk According to Effect Modification by Helicobacter pylori Infection / Journal of the Korean Cancer Association, 대한암학회지

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.

Age-Period-Cohort Analysis of Female Breast Cancer Mortality in Korea / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Despite the low mortality rate of breast cancer among women in Korea, the breast cancer mortality rate has increased. The aim of this study was to examine trends in breast cancer mortality from 1983 to 2012 in Korea, assessing the importance of age, period, and birth cohort as risk factors. MATERIALS AND METHODS: Data on the annual number of deaths due to female breast cancer and on female population statistics from 1983 to 2012 were obtained from Statistics Korea. A log-linear Poisson age-period-cohort model was used to estimate age, period, and cohort effects. RESULTS: The increasing breast cancer mortality can be explained predominantly by a birth cohort effect: the risk of breast cancer death showed a steady increase until the 1968 birth cohort, and decreased thereafter. There was a sharp increase in the magnitude of the age effect up to 60 years old, then a moderate increase in the effect during the sixties, followed by another sharp increase from 70 years old. The period effect on breast cancer mortality seems negligible based on its adjusted relative risk, even though it was statistically significant after adjusting for age and cohort effects. CONCLUSION: In this study, the mortality pattern of breast cancer in Korea can be explained predominantly by a birth cohort effect. Hence, the overall mortality rate of breast cancer may increase for a while, and show a gradual decrease in the future, which will start from the younger age group.

Alcohol Drinking, Cigarette Smoking and Risk of Colorectal Cancer in the Korean Multi-center Cancer Cohort

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 > or = 30 years of consumption compared to non-drinkers; HR 2.24 [1.31-3.84] for > or = 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.

WHO Western Pacific Regional Action Plan for the Prevention and Control of NCDs (2014-2020) / 한국역학회지

No abstract available.

A Prospective Cohort Study on the Relationship of Sleep Duration With All-cause and Disease-specific Mortality in the Korean Multi-center Cancer Cohort Study / 예방의학회지

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 or =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 > or =60 years. Risk of cardiovascular disease-specific mortality was associated with a sleep duration of or =10 hours). CONCLUSIONS: Sleep durations of 7 to 8 hours may be recommended to the public for a general healthy lifestyle in Korea.

Interaction of Body Mass Index and Diabetes as Modifiers of Cardiovascular Mortality in a Cohort Study / 예방의학회지

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/m2), lean subjects with diabetes (BMI or =25 kg/m2) had no increased death risk (p-interaction <0.05). This pattern was consistent in sub-populations with no incidence of hypertension. CONCLUSIONS: This study suggests that diabetes in lean people is more critical to CVD deaths than it is in obese people.

Prevalence and Seroprevalence of Low-Risk Human Papillomavirus in Korean Women

Little is known about the prevalence and seroprevalence of low-risk human papillomavirus (HPV) and the risk factors for HPV infection in Korean women. We determined the prevalence of low-risk HPV among 902 women aged 20-59 yr and the seroprevalence of low-risk HPV subtypes 6 and 11 among 1,094 women aged 9-59 yr in the general population. Genital low-risk HPV DNA was assessed by liquid hybridization and polymerase chain reaction. Antibody titers against HPV 6 and 11 were measured by a multiplexed competitive luminex technique. The prevalence of genital low-risk HPV was 4.9%. It reached its highest peak of 10.3% at 20-29 yr of age and a second peak of 3.2% at 50-59 yr of age. The seroprevalence of HPV 6 or 11 was 9.4%. It reached its highest peak of 12.7% at 25-29 yr of age and a second peak of 12.3% at 50-59 yr of age. In multivariable analysis, the number of lifetime sexual partners and past history of sexually transmitted diseases were associated with the seroprevalence but not prevalence of HPV. It is suggested that younger women should receive prophylactic HPV vaccination before they become sexually active and exposed to HPV in their 20s. This study provides baseline data for developing HPV vaccination programs and monitoring vaccine efficacy in Korea.

Alcohol Consumption and Mortality in the Korean Multi-center Cancer Cohort Study / 예방의학회지

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 Multi-center 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.

Descriptive Epidemiology of Cholangiocarcinoma and Clonorchiasis in Korea

In 2009, infection with the liver fluke Clonorchis sinensis (C. sinensis) was classified as "carcinogenic to humans" (Group 1) based on its involvement in the etiology of cholangiocarcinoma by the International Agency for Research on Cancer. However, little is known about the descriptive epidemiology of cholangiocarcinoma in Korea. We examined incidence trends of intrahepatic and extrahepatic cholangiocarcinomas, using data from the Korea National Cancer Incidence database for 1999-2005. The prevalence of C. sinensis infection was estimated from a recent population-based survey in rural endemic areas. Cholangiocarcinoma incidence rates are currently rising, even while primary liver cancer incidence rates are decreasing. Annual percent changes in cholangiocarcinoma incidence rates were 8% for males and 11% in females. Known areas of C. sinensis endemicity showed high incidence rates of cholangiocarcinoma. The positivity of C. sinensis eggs in stool samples from endemic areas was more than 25% of adults tested during 2005-2008. From a meta-analysis, the summary odds ratio for cholangiocarcinoma due to C. sinensis infection was 4.7 (95% confidence interval: 2.2-9.8). Approximately 10% of cholangiocarcinomas in Korea were caused by chronic C. sinensis infections. More specific policies, including health education and an extensive effort for early detection in endemic areas, are needed.

Cancer Statistics in Korea: Incidence, Mortality and Survival in 2006-2007

Cancer has been the leading cause of death in Korea. Korea is facing a very rapid change and increase in cancer incidence, which draws much attention in public health. This paper overviews the nationwide cancer statistics, including incidence, mortality, and survival rates, and their trends in Korea based on the cancer incidence data from The Korea Central Cancer Registry (KCCR) in year 2006 and 2007. In Korea, there were 153,237 cancer cases and 65,519, cancer deaths observed in 2006, and 161,920 cancer cases and 67,561 cancer deaths in 2007, respectively. The incidence rate for all cancer combined showed an annual increase of 2.8% from 1999 to 2007. Specifically, there was significant increase in the incidence of colorectal, thyroid, female breast, and prostate cancers. The number of cancer deaths has increased over the past two decades, due mostly to population aging, while the age-standardized mortality rates have decreased in both men and women since 2002. Notable improvement has been observed in the 5-yr relative survival rates for most major cancers and for all cancer combined, with the exception of pancreatic cancer. The nationwide cancer statistics in this paper will provide essential data for cancer research and evidence-based health policy in Korea.

Cigarette Smoking and Mortality in the Korean Multi-center Cancer Cohort (KMCC) Study / 예방의학회지

OBJECTIVES: The aim of this study was to evaluate the association between cigarette smoking and total mortality, cancer mortality and other disease mortalities in Korean adults. METHODS: A total of 14 161 subjects of the Korean Multi-center Cancer Cohort who were over 40 years of age and who were cancer-free at baseline enrollment reported their lifestyle factors, including the smoking status. The median follow-up time was 6.6 years. During the follow-up period from 1993 to 2005, we identified 1159 cases of mortality, including 260 cancer mortality cases with a total of 91 987 person-years, by the national death certificate. Cox proportional hazard regression model was used to estimate the hazard ratio (HR) of cigarette smoking for total mortality, cancer mortality and disease-specific mortality, as adjusted for age, gender, the geographic area and year of enrollment, the alcohol consumption status, the education level and the body mass index (BMI). RESULTS: Cigarette smoking was significantly associated with an increased risk of total mortality, all-cancer mortality and lung cancer mortality (p-trend, <0.01, <0.01, <0.01, respectively). Compared to non-smoking, current smokers were at a higher risk for mortality [HR (95% CI)=1.3 (1.1-1.5) for total mortality; HR (95% CI)=1.6 (1.1-2.2) for all-cancer mortality; HR (95% CI)=3.9 (1.9-7.7) for lung cancer mortality]. CONCLUSIONS: This study's results suggest that cigarette smoking might be associated with total mortality, all-cancer mortality and especially lung cancer mortality among Korean adults.

Nationwide Cancer Incidence in Korea, 2003-2005 / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: To estimate the current cancer burden in Korea, newly diagnosed cancer cases and cancer incidence rates were calculated for the years 2003~2005. MATERIALS AND METHODS: The cancer incidence cases and rates were calculated from the Korea National Cancer Incidence Database. Crude and age-standardized incidence rates were calculated by gender for specified cancer sites in 5-year age groups. RESULTS: From 2003 to 2005, 398,824 cases of cancer were newly diagnosed in Korea (218,856 in men and 179,968 in women). For all sites combined, the crude incidence rate (CR) was 300.0 and 248.2 for men and women and the age-standardized incidence rate (ASR) was 297.0 and 191.2 per 100,000, respectively. Among men, five leading cancers were stomach (CR 66.0, ASR 64.2), lung (CR 48.5, ASR 50.3), liver (CR 44.9, ASR 42.1), colon and rectum (CR 37.9, ASR 37.2), and prostate cancer (CR 12.7, ASR 13.8). Among women, five leading cancers were breast (CR 37.3, ASR 29.0), thyroid (CR 36.2, ASR 28.8), stomach (CR 34.1, ASR 25.4), colon and rectum (CR 28.0, ASR 21.1), and lung cancer (CR 17.9, ASR 12.8). In the 0~14-year-old group, leukemia was the most common in both sexes; in the 15~34 group, the most common cancer was stomach cancer for men and thyroid cancer for women; in the 35~64 group, stomach cancer for men and breast cancer for women; among those 65 and over, lung cancer for men and stomach cancer, for women, respectively. CONCLUSION: The cancer incidence rates have increased in recent years, and more cancers are expected to develop as Korea is quickly becoming an aged society. The cancer incidence statistics in this report can be used as an important source to effectively plan and evaluate the cancer control program in Korea.

Cancer Statistics in Korea: Incidence, Mortality and Survival in 2005

Cancer has been the most common cause of death in Korea since 1983 and is a major public health concern. This paper overviews the nationwide cancer statistics, including incidence, mortality, and survival rates, and their trends in Korea. In 2005, 142,610 new cancer cases and 65,117 cancer deaths occurred in Korea. The incidence rate for all cancer combined increased by 2.6% annually from 1999 to 2005. Significant increases have occurred in the incidence of colorectal, thyroid, female breast, and prostate cancers. The number of cancer deaths has increased over the past two decades, due mostly to population aging, while the age-standardized mortality rates have decreased in both men and women since 2002. Notable improvement has been observed in the 5-yr relative survival rates for most major cancers and for all cancer combined, with the exception of pancreatic cancer. The nationwide cancer statistics in this paper will provide essential data for evidence-based decisions in the national cancer control program in Korea.

Diagnostic accuracy of conventional Pap test, liquid-based cytology and human papillomavirus DNA testing in cervical cancer screening in Korea: a meta-analysis / 한국역학회지

No abstract available.

Comparison of Cancer Survival by Age Group for 1997 and for 2002: Application of Period Analysis using the National Cancer Incidence Database / 예방의학회지

OBJECTIVES: Period analysis estimates up-to-date survival rates of cancer patients. In this approach, analysis is restricted to recent time period by left-truncating all observations at the beginning of the period and rightcensoring at its end. Here, we applied period analysis to examine changes in 5-year relative survival (RS) by age group for 1997 and for 2002. METHODS: Using the National Cancer Incidence Database, 5-year RS was estimated for 1997 and 2002 in four age groups (15-54, 55-64, 65-74, and 75 years old and over) using period analysis. After excluding death certificate-only cases, patients with an unknown date of diagnosis or follow-up length, a total of 813,889 patients diagnosed with a first primary invasive cancer during 1992-2002 were included for analysis. Followup for vital status was included until 31 December 2002. RESULTS: Five-year RS increased from 41.7% for 1997 to 46.7% for 2002. Increases in survival occurred in all age groups except in the 75 and over group. CONCLSIONS: The age gradient in cancer prognosis seems to have widened between 1997 and 2002, a finding that requires further study of prognostic factors, including stage at diagnosis. Period analysis accurately estimates survival rates, especially for cancers with better prognosis.

Erratum: Global Activity of Cancer Registries and Cancer Control and Cancer Incidence Statistics in Korea / 예방의학회지

No abstract available.

Global Activity of Cancer Registries and Cancer Control and Cancer Incidence Statistics in Korea / 예방의학회지

The World Health Organization (WHO) reported that cancer killed 7.6 million people in the world in 2005, and that 40% of all cancer deaths can be prevented. According to the WHO Global Action Plan Against Cancer (GAPAC), monitoring of cancer patients is the essential part of cancer control, and should be conducted through cancer registration. Originally, cancer registries were primarily concerned with the description of cancer patterns, trends of cancer occurrence, and etiology of cancer. In the last 20 years, cancer registries provided not only information on the incidence and characteristics of specific cancers, but also supplied the source of cancer control planning and evaluation and the care of individual cancer patients with survival. Cancer Incidence in Five Continents (CI5) presents incidence data from populations all over the world every five year. Volume IX in the series (data for 1998-2002) has recently (November 2007) been published online at International Agency for Research on Cancer (IARC). Nine data from Korea Central Cancer Registry (National data), Seoul, Busan, Daegu, Gwangju, Incheon, Daejeon, Usan, Jejudo regional cancer registries were included in that volume. In this paper, the editorial process, the characteristics of national data, and quality indices in CI5 IX are being described. In addition, cancer control activities related to cancer registration in some selected countries are also presented.

Knowledge of human papillomavirus infection and acceptability of vaccination among adult women in Korea / 대한산부인과학회지

OBJECTIVE: The HPV vaccination target adolescents, and may be influenced by opinion of parents and other family member. For implementation of HPV vaccine, we measured knowledge of HPV infection and acceptability of vaccination among adults in Korea. METHODS: From August 2006 to November 2007, we provided a written questionnaire to females (above 19 years- olds) who visited Il-sin Christian hospital for prenatal care or gynecological examination. The questionnaire was built using elements of The Health Belief Model. We measured (1) awareness of HPV (2) perceived susceptibility (3) perceived seriousness (4) perceived benefit of vaccination (5) perceived barriers (6) cues to action. RESULTS: Total 975 females answered the questionnaire, and the mean age was 40 years. Only 23.8% knew the fact cervical cancer is related to HPV infection. 78.3% of respondents were willing to accept HPV vaccination after they understood HPV vaccination can prevent cervical cancer. Financial burden and possible side effect were barriers to vaccination. CONCLUSIONS: Despite of low awareness of HPV infection, most (78.3%) adults favored having HPV vaccination. But the vaccine was more likely to be accepted if it is recommended by a physician and reasonably priced.

Introduction of Relative Survival Analysis Program: Using Sample of Cancer Registry Data with Stata Software / 한국역학회지

Patient survival is one of the most important measures for the evaluation of progress in cancer patient care across the wide spectrum from diagnosis to treatment. The optimal monitoring method for cancer patient survival is to estimate survival based on representative data from cancer patients in the population, which is only achievable through using population-based cancer registration data. Relative survival is used to compare the survival experience in a study cohort that expected to result from background population mortality rates. This technique is useful when the cause of death is not accurate or not available, since it provides a measure of excess mortality in a group of patients with a certain disease. The purpose of this article is to demonstrate the procedures for estimating relative survival using the statistical software Stata. For this survival analysis to show the procedure, the example data set was randomly selected from the National Cancer Incidence Database, which was used in a recent article reporting the overall relative survival of cancer patients diagnosed during 1993-2002 in Korea.

Cigarette Smoking, Alcohol Consumption, Tuberculosis and Risk of Lung Cancer: The Korean Multi-center Cancer Cohort Study / 예방의학회지

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 physiciandiagnosed 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 noncases]. There was no statistically significant interaction between cigarette smoking and alcohol consumption (pinteraction = 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.