Cancer Risk According to Alcohol Consumption Trajectories: A Population-based Cohort Study of 2.8 Million Korean Men.

BACKGROUND: Alcohol drinking behaviors change temporally and can lead to changes in related cancer risks; previous studies have been unable to identify the association between the two using a single-measurement approach. Thus, this study aimed to investigate the association of drinking trajectories with the cancer risk in Korean men. METHODS: A trajectory analysis using group-based trajectory modeling was performed on 2,839,332 men using data on alcohol drinking levels collected thrice during the Korean National Health Insurance Service's general health screening program conducted between 2002 and 2007. Cox proportional hazards regression was performed to evaluate the associations between drinking trajectories and cancer incidence, after adjustments for age, income, body mass index, smoking status, physical activity, family history of cancer, and comorbidities. RESULTS: During 10.5 years of follow-up, 189,617 cancer cases were recorded. Six trajectories were determined: non-drinking, light, moderate, decreasing-heavy, increasing-heavy, and steady-heavy. Light-to-heavy alcohol consumption increased the risk for all cancers combined in a dose-dependent manner (adjusted hazard ratio [aHR] 1.03; 95% confidence interval [CI], 1.02-1.05 for light drinking, aHR 1.06; 95% CI 1.05-1.08 for moderate drinking, aHR 1.19; 95% CI, 1.16-1.22 for decreasing-heavy drinking, aHR 1.23; 95% CI, 1.20-1.26 for increasing-heavy drinking, and aHR 1.33; 95% CI, 1.29-1.38 for steady-heavy drinking [P-trend <0.001]). Light-to-heavy alcohol consumption was linked to lip, oral cavity, pharyngeal, esophageal, colorectal, laryngeal, stomach, and gallbladder and biliary tract cancer risks, while heavy alcohol consumption was associated with hepatic, pancreatic, and lung cancer risks. An inverse association was observed for thyroid cancer. The cancer risks were lower for decreasing-heavy drinkers, compared to steady-heavy drinkers. CONCLUSION: No safe drinking limits were identified for cancer risks; reduction in heavy intake had protective effects.

Vision for tobacco endgame in Korea: suggestions for countries with endgame aspirations.

Tobacco endgame is a focal point of discussion at both national and international levels. We aimed to describe efforts related to achieving the tobacco endgame in the Republic of Korea, an exemplar of a country with endgame aspirations, and compare them with the efforts of other nations. We reviewed the tobacco endgame efforts of three nations considered tobacco control leaders: New Zealand (NZ), Australia and Finland. The efforts/attempts of each country were described using an endgame strategy category. The tobacco control leaders had explicit goals to achieve a smoking prevalence of <5% before a target date and had legislation and research centres for tobacco control and/or endgame. NZ is implementing a mixture of conventional and innovative endgame interventions; the others use incremental conventional approaches. In Korea, there has been an attempt to ban the sale and manufacture of combustible cigarettes. The attempt led to the filing of a petition, and a survey of adults showed 70% supported the legislation banning tobacco. The Korean government mentioned a tobacco endgame in a 2019 plan, yet a target and an end date were absent. The 2019 plan in Korea included incremental FCTC strategies. Practices in the leading countries show that legislation and research are key to ending the tobacco epidemic. The MPOWER measures must be strengthened, endgame objectives must be set and bold strategies must be adopted. Key endgame policies include those with evidence of effectiveness, such as retailer reductions.

Optimum Urine Cotinine and NNAL Levels to Distinguish Smokers from Non-Smokers by the Changes in Tobacco Control Policy in Korea from 2008 to 2018.

INTRODUCTION: We examined the age- and sex-specific distributions of biomarkers of tobacco smoke exposure to determine the optimal cutoffs to distinguish smokers from non-smokers over the last 10 years in Korea, during which smoking prevalence and secondhand smoke (SHS) exposure declined due to changes in tobacco control policy. METHODS: We analyzed data from the Korea National Health and Nutrition Examination Survey on creatinine-adjusted urinary cotinine (2008-2018; 33 429 adults: 15 653 males and 17 776 females) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL; 2016-2018; 6337 adults: 3091 males and 3246 females). We determined the optimal cutoffs and confidence intervals (CIs) to distinguish smokers from non-smokers using receiver operator characteristic curve analysis and bootstrapping (1000 resamples). RESULTS: The optimal cutoff values of creatinine-adjusted urine cotinine and NNAL concentration were 20.9 ng/mg (95% CI: 20.8-21.0, sensitivity: 96.6%, specificity: 93.8%) and 8.9 pg/mg (95% CI: 8.8-8.9, sensitivity: 94.0%, specificity: 94.7%), respectively, in 2016-2018. The optimal cutoffs of both biomarkers increased with age and were higher in females than in males for NNAL concentration. In both sexes, the optimal cutoff of urine cotinine continuously declined over the study period. CONCLUSIONS: The optimal cotinine cutoff declined along with smoking prevalence and levels of SHS exposure due to enforcement of tobacco control policies, including smoke-free ordinances and tax increases. Monitoring of biomarkers of tobacco exposure appears necessary for verification of smoking status and regulatory use. IMPLICATIONS: Our results based on nationally representative data suggest that a large decrease in the optimal cutoff value of urine cotinine to distinguish smokers from non-smokers was caused by decreases in smoking prevalence and SHS exposure following enforcement of tobacco control policies over the last 10 years. We determined the optimal cutoff values of urine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL), which were not previously reported in representative population in Asia, to enable more accurate estimation of exposure to tobacco smoke and proper assessment of disease risks. Gender- and age-specific differences in the optimal cutoffs require further study. Monitoring of biomarkers of tobacco smoke exposure seems necessary for verification of smoking status and regulatory use.

Perceptions of Heated Tobacco Products (HTPs) and Intention to Quit Among Adult Tobacco Users in Korea.

BACKGROUND: The popularity of heated tobacco products (HTPs) has been growing globally but, limited information exists on tobacco use behaviors and its impact on tobacco control. This study investigates awareness and perception of HTPs among tobacco users and whether perceptions of HTPs are associated with HTP use and intention to quit. METHODS: We invited 2,000 tobacco users aged 19-65 years with countrywide representation to an online survey in November 2018. Information on general characteristics, tobacco use behaviors, awareness and perception of HTPs, and intention to quit were gathered. Multinomial logistic regression analysis and ANCOVA were used for estimation of association and comparison. RESULTS: Among all tobacco users, 36.8% were classified as ever users, whereas 28.3% had used HTPs in the past 30 days, which was higher than expected. Users of liquid-based e-cigarettes (odds ratio [OR] 1.578; 95% confidence interval [CI], 1.210-2.056) and poly-product users (OR 2.029; 95% CI, 1.121-3.671) showed higher intention to quit within 1 month when compared to users of conventional cigarettes (CCs), whereas HTP users and dual product users did not. HTP users rated HTPs more favorably than CCs in terms of smoke, smell, harm, aid in quitting, design, and price than users of other products did (P-value < 0.001). CONCLUSION: We find that positive perception of HTPs following strategic marketing from tobacco companies could have contributed to a greater increase in HTP use than expected in Korea. However, HTPs might not be considered substitutes for CCs for quitting tobacco use because a significant proportion of dual product users reported a lower intention to quit.

Association between perceived harm of tobacco and intention to quit: a cross-sectional analysis of the Vietnam Global Adult Tobacco Survey.

BACKGROUND: Perception of harm plays an important role in predicting intention to quit-an integral part of the cessation process. Perception on harm from bamboo waterpipe tobacco was unknown, even the predominant of this type of tobacco use. This study investigated the effects of perceived harm from cigarette and bamboo waterpipe tobacco on intention to quit among adult male Vietnamese tobacco users. METHODS: From the nationally-representative 2015 Global Adult Tobacco Survey, we included 1,351 adult males (≥ 18 years old) who used cigarettes, bamboo waterpipes, or both. Demographic characteristics, tobacco use behaviors, perceived harm from tobacco use, and regulation/policy exposure were measured. Effects of perceived harm from cigarette and bamboo waterpipe tobacco on intention to quit were assessed by logistic regression. RESULTS: Intention to quit prevalence was 59.0%, 55.0%, and 58.4% for cigarette, waterpipe, and dual users, respectively. Tobacco users who perceived that "using cigarettes and/or waterpipe could cause severe illness" and "waterpipe use is less harmful than cigarette smoking", had tobacco use bans at home, or were exposed to anti-smoking campaigns or encouragement to quit information were more likely to intend to quit. When analyzed by tobacco users, intention to quit was more likely for those users who perceived their tobacco product as more harmful than the other product type, although statistical significance was only observed for cigarette users. CONCLUSIONS: Misperceptions regarding harm from tobacco use could negatively affect intention to quit. Dissemination of accurate information on the risks from all forms of tobacco use and enforcement of tobacco control policies are important for encouraging intention to quit.

Trends in the Socioeconomic Inequalities Related to Second-Hand Smoke Exposure as Verified by Urine Cotinine Levels Among Nonsmoking Adults: Korea National Health and Nutrition Examination Survey 2008-2018.

INTRODUCTION: The expansion of smoke-free policies has reduced the prevalence of second-hand smoke (SHS) exposure; however, declines differ according to socioeconomic positions. We evaluated the trends in socioeconomic inequalities related to SHS exposure in nonsmoking Korean adults from 2008 to 2018. METHODS: We analyzed 30,027 nonsmoking adults from the Korea National Health and Nutrition Examination Survey 2008 to 2018. We evaluated trends in urine cotinine levels, self-reported prevalence of SHS exposure at workplaces and homes, and people exhibiting nonmeasurable urine cotinine levels between 2008 and 2018. To evaluate the yearly decline differences of urine cotinine levels according to socioeconomic positions, we calculated the interaction effects of year and education, household incomes, and occupation from linear regression analysis. RESULTS: In the last 11 years, the geometric means of urine cotinine levels decreased from 3.53 (95% CI 2.96-4.19) ng/mL to 0.60 (0.57-0.64) ng/mL in males, and from 2.36 (2.03-2.73) ng/mL to 0.53 (0.51-0.56) ng/mL in females. The prevalence of SHS exposure at workplaces and homes also declined. In the multivariate model, the interaction effects between education and years were significant; therefore, indicating a substantial yearly decline of urine cotinine levels in higher educated individuals. The interaction effects between household incomes and years were only significant among males; the interaction effects between occupations and years were not significant. CONCLUSIONS: SHS exposure in nonsmoking Korean adults has consistently decreased; however, socioeconomic inequalities related to SHS exposure by education level have widened. Policies targeting socioeconomically disadvantaged populations should be implemented to decrease the disparities of SHS exposure. IMPLICATIONS: Along with tobacco control policies, the prevalence of self-reported and urinary cotinine verified SHS exposure has decreased in the last 11 years. In contrast, the socioeconomic inequalities related to SHS exposure by education level have increased over time. This study emphasizes the need for implementing tobacco control policies to reduce disparities of SHS exposure.

How Much Is Too Much? Estimating Effective Price-Hikes to Affect Smoking Behavior in Vietnam.

INTRODUCTION: Raising the price of cigarettes is one of the most effective strategies to reduce cigarette smoking. The Vietnamese government is working toward the tobacco control goal of a 10% reduction in smoking prevalence by 2020. However, cigarette prices in Vietnam have not increased in the last two decades. The aim of this study was to estimate what cigarette prices would make smokers attempt to quit smoking, and to identify predictors of the price to quit and the intention to quit. METHODS: A cross-sectional survey was conducted with 822 male current smokers in Da Nang, Vietnam. A structured questionnaire was adapted from the International Tobacco Control project survey. Bayesian quantile regression was applied to predict factors associated with expected cigarette price. RESULTS: Fifty-six percent of smokers suggested a price to quit. Their median suggested price to quit per pack, 62 000 VND (2.8 USD), was 2.8 times higher than the actual current price, 22 000 VND (1.01 USD). Suggesting a lower price to quit was significantly associated with awareness of warning labels and smoke-free policies. In contrast, being a heavy smoker was significantly associated with a higher suggested price to quit across all quantiles. CONCLUSIONS: There may be sufficient room to increase cigarette prices in Vietnam. The price to quit is associated with various factors, including non-pricing policies. IMPLICATIONS: Evidence suggests that a steep increase in cigarette prices, setting a high minimum tax, and introducing a large specific tax, which are policy-induced price increases that can raise prices substantially in Vietnam, are preferable strategies. In addition to increasing price and taxes, the government should also strengthen non-pricing policies.

User characteristics of national smoking cessation services in Korea: who chooses each type of tobacco cessation program?

BACKGROUND: Relatively little is known about which characteristics of smokers are related to choosing a specific type of smoking cessation service. The user characteristics of different smoking cessation services were compared to determine the service preferred by user characteristics. METHODS: The characteristics of adult smokers from Korea National Health and Nutrition Examination Survey (3762) and registered users of national smoking cessation services operated through the web (14,762), at Public Health Center-based Smoking Cessation Clinics (PHC-based SCCs) (335,532), and by telephone (Quitline) (2983) were compared. RESULTS: Females and younger aged were more in web and telephone-based cessation service users, while aged 50 years or older were more in PHC-based SCCs users. Although manufacturing and production workers were the most prevalent among smokers in the general population, office workers and others including housewives and unemployed were most prevalent among the users of Quitline and PHC-based SCCs, respectively. The number of cigarettes smoked per day was twice as high among cessation service users as in general population. Smokers with greater nicotine dependency were most prevalent in the web-based service. Overseas users were in the web-based cessation service. CONCLUSION: Identifying user-specific characteristics by the type of cessation services looks necessary to develop and offer appropriate cessation services.

Influences of Tobacco-Related Knowledge on Awareness and Behavior towards Smoking.

BACKGROUND: A considerable amount of research has shown that knowledge and appropriate awareness are essential for encouraging positive behaviors and promoting health. In Korea, the roles that behavioral changes play in the prevention of cancer have been an important issue since the introduction of the 10 codes for cancer prevention in 2006. Thus, the present study investigated the associations of tobacco-related knowledge with awareness and attitudes towards positive smoking-cessation behaviors. METHODS: The present study analyzed data from the 2010 national questionnaire survey (n = 1,006). This study evaluated sociodemographic characteristics, smoking status, self-rated health status, health-related interests, and the accuracy of 12 tobacco-related statements to determine knowledge level and to investigate its impact on awareness and behaviors related to smoking. These parameters were examined and staged using the Precaution Adoption Process Model. RESULTS: A higher level of tobacco-related knowledge was significantly associated with a positive attitude towards smoking cessation (5-8 correct answers: odds ratio [OR], 2.53; 95% confidence interval [CI], 1.57-4.08; ≥ 9 correct answers: OR, 3.90; 95% CI, 2.22-6.82; reference: ≤ 4 correct answers). Interestingly, among current smokers, only those who correctly responded to ≥ 9 of 12 tobacco-related statements were significantly associated with a positive attitude towards smoking cessation. CONCLUSION: This study found that having a higher level of tobacco-related knowledge had a significant impact on positive attitudes towards smoking cessation. This suggests that there is a need to disseminate appropriate knowledge to the general population to encourage positive attitudes and promote healthful behaviors in terms of smoking.

Urban-rural differences in the prevalence of allergen sensitization and self-reported rhinitis in the elderly population.

BACKGROUND: Urbanization is frequently associated with allergic conditions during childhood; however, the literature lacks studies on the association between allergies and degree of urbanization in the elderly population. OBJECTIVE: To determine how the degree of urbanization affects the prevalence of allergic sensitization and self-reported rhinitis symptoms in elderly community populations. METHODS: The study population consisted of 1,311 elderly subjects identified from 2 community population cohort datasets who were divided into 3 groups according to the degree of urbanization (urban, semirural, and rural) where they resided. Current rhinitis symptoms were assessed using a questionnaire. Sensitization to inhalant allergen was measured using skin prick tests for 9 common allergens. RESULTS: Sensitization to inhalant allergen showed a positive correlation with degree of urbanization (urban 17.2%, semirural 9.8%, rural 6.0%; P for trend <.001), with a significant correlation observed between house dust mite allergens and degree of urbanization. Self-reported rhinitis symptoms were mostly nonallergic, but showed a positive correlation with degree of urbanization (urban 26.8%, semirural 18.2%, rural 11.5%; P for trend <.001). Self-reported rhinoconjunctivitis also correlated with urbanization. Correlations between self-reported allergic conditions and urbanization remained statistically significant in multivariate logistic regression tests. CONCLUSION: The present analyses found significant correlations between degree of urbanization with self-reported rhinitis symptoms and sensitization to inhalant allergen in the elderly population. These findings warrant further investigation of the roles that urban factors play in the development of elderly rhinitis and allergen sensitization.

Control of clonorchiasis in Korea: effectiveness of health education for community leaders and individuals in an endemic area.

OBJECTIVES: To develop effective intervention programmes to control Clonorchis sinensis infection, three interventions were evaluated in a clonorchiasis-endemic area of Korea. METHODS: Four thousand two hundred and sixty-seven voluntary participants in Sancheong county were tested at baseline and two follow-up surveys after 1 and 3 years. Faecal samples were examined for C. sinensis eggs using the Kato-Katz method. Participants were divided into three intervention groups by areas and year recruited: national prevention programme only (mass health campaign and praziquantel treatment) for Group A; health education for community leaders added for Group B; and individual health education added for Group C. RESULTS: The prevalence of C. sinensis infection fell substantially in all three intervention groups between baseline and 3-year follow-up: from 31.1% to 14.9% in Group A, from 29.6% to 6.8% in Group B and from 21.9% to 8.6% in Group C. The control effectiveness was highest in Group B with 76.8%. The new infection rate was 16.3%, 12.8% and 7.6% in Group A, B and C, respectively. The reinfection rate was lower in Group B (3.8%) than Group C (12.2%). CONCLUSIONS: To control C. sinensis infection in endemic areas of Korea, health education for community leaders or individuals on prevention of C. sinensis infection should be added to national control programmes.

Tolerance for and potential indicators of second-hand smoke exposure among nonsmokers: a comparison of self-reported and cotinine verified second-hand smoke exposure based on nationally representative data.

OBJECTIVE: We assessed the extent to which self-reported exposure to SHS underestimates the actual exposure to SHS and what factors are associated with a tolerance for SHS exposure in the Korean setting where the smoke-free policy is incomplete. METHODS: Information on socio-demographic characteristics, alcohol drinking and smoking was collected for 7948 nonsmokers aged ≥ 19 years from the fourth Korea National Health and Nutrition Examination Survey, 2008-2009. Self-reported and cotinine verified SHS exposures were compared. Potential factors associated with cotinine verified but not self-reported SHS exposures were assessed using a logistic regression model. RESULTS: Self-reported SHS exposure significantly underestimated the actual SHS exposure as determined by cotinine verification (kappa coefficient: 0.1066). At younger age, frequent alcohol drinking in females and a longer smoking duration in males were positively associated with cotinine verified exposure but not with the self-reported SHS exposure; they were also positively associated with cotinine verified exposure irrespective of self-reported SHS exposure. CONCLUSIONS: Our findings show a tolerance for smoking in Korea. The current partial ban on smoking does not fully protect people from exposure to SHS. Smoking should be banned in all public places. In addition, efforts to de-normalize smoking in the Korean culture need to be strengthened.

Tobacco control challenges in East Asia: proposals for change in the world's largest epidemic region.

East Asia is one of the world's largest tobacco epidemic regions. Although several international studies have evaluated the status of tobacco control in this region, the findings have not been integrated with knowledge on domestic activities at the national and municipal levels. We analysed the current tobacco control situation in three East Asian countries, Japan, China and the Republic of Korea, using both international and domestic data sources. We collected data between 2008 and 2011 in each country according to the framework of WHO's MPOWER (Monitoring, Protect, Offer, Warn, Enforcement and Raise) approach for guiding implementation of the WHO Framework Convention on Tobacco Control. Analysis revealed that 37-53% of adult men were current smokers and that smoking prevalence among middle-aged men reached 63%. Less than 20% of male smokers plan to quit and the use of nicotine replacement drugs was 14% at maximum. Forty-six percent or more of men and 20% or more of women were exposed to passive smoking at workplaces and at home, respectively. Many tobacco industry activities remain unrestricted and prevalent. Our findings indicate an urgent need for the following set of policies: raise cigarette prices to increase the quit attempt rate, particularly among adult men; develop a multi-component quitting assistance system to provide adequate assistance for smoking cessation; implement effective smoke-free policies in workplaces and public places to reduce exposure to passive smoking; and rebuild the administrative structure to denormalise tobacco industry activities. The importance of these standard approaches should be reaffirmed by all tobacco control policymakers in East Asia.

National Smoking Cessation Services (NSCS) enrollment and their effect on long-term tobacco cessation in Korea: Results from a 1-year prospective follow-up of NSCS participants.

INTRODUCTION: The study aimed to identify predictors associated with long-term tobacco cessation at 12-month follow-up among users of the National Smoking Cessation Services (NSCS) in Korea. METHODS: To measure the long-term effect of NSCS delivery, the target sample size of 5167 adult smokers registered in the NSCS in 2018 was enrolled with proportional random sampling. A multiple logistic regression analysis (crude, adjusted) was performed to identify the changes in smoking status at the 12-month follow-up after the last NSCS enrollment and the potential factors associated with changes in smoking status. RESULTS: The response rate to reach the number of subjects targeted was 22.4%. A total of 41.2% of the tobacco users enrolled had successfully quit at baseline, and the 7-day point prevalence of tobacco cessation at the follow-up at 12 months, via a telephone survey, was 34.4%. Factors positively associated with cessation at the 12-month follow-up were longer experience with tobacco abstinence and additional quitting attempts with or without NSCS enrollment, although every additional quit attempt with NSCS use had a better outcome. In addition, having a successful quit outcome with NSCS use at the baseline and having more satisfaction with the service of professional counseling or incentives than others provided by NSCS, increased cessation at follow-up after adjustment of other factors considered. CONCLUSIONS: In addition to multiple quitting attempts, longer experience with tobacco abstinence, and additional enrollment in NSCS, the service experience, and satisfaction with the content that NSCS offered, might improve the lasting success of abstinence. These results might be considered to improve the contents and protocols of the NSCS for better outcomes.

Cancer Risk Following Smoking Cessation in Korea.

Importance: Tobacco smoking is associated with increased risk of various cancers, and smoking cessation has been associated with reduced cancer risks, but it is still unclear how many years of smoking cessation are required to significantly reduce the cancer risk. Therefore, investigating the association of smoking cessation with cancer is essential. Objective: To investigate the time course of cancer risk according to the time elapsed since smoking cessation and the benefits of smoking cessation according to the age at quitting. Design, Setting, and Participants: This population-based, retrospective cohort study included Korean participants aged 30 years and older who underwent 2 or more consecutive health examinations under the National Health Insurance Service since 2002 and were followed-up until 2019. Data analysis was performed from April to September 2023. Exposures: Exposures included (1) time-updated smoking status based on biennial changes in smoking status, defined as complete quitters, transient quitters, relapsed quitters, continuous smokers, and never smokers; (2) duration of smoking cessation, defined as years since quitting; and (3) categorical variable for age at quitting. Main Outcomes and Measures: The primary cancer was ascertained using the cancer registry data: all-site cancer (International Statistical Classification of Diseases and Related Health Problems, Tenth Revision [ICD-10] codes C00-43, C45-96, or D45-D47), lung cancer (ICD-10 code C34), liver cancer (ICD-10 code C22), stomach cancer (ICD-10 code C16), and colorectal cancer (ICD-10 codes C18-20). Hazard ratios (HRs) and 95% CIs were estimated using a Cox proportional hazards regression model with follow-up years as the timescale. Results: Of the 2 974 820 participants, 1 727 340 (58.1%) were men (mean [SD] age, 43.1 [10.0] years), and 1 247 480 (41.9%) were women (mean [SD] age, 48.5 [9.9] years). Over a mean (SD) follow-up of 13.4 (0.1) years, 196 829 cancer cases were confirmed. Compared with continuous smokers, complete quitters had a lower risk of cancer, with HRs of 0.83 (95% CI, 0.80-0.86) for all cancer sites, 0.58 (95% CI, 0.53-0.62) for lung, 0.73 (95% CI, 0.64-0.82) for liver, 0.86 (95% CI, 0.79-0.93) for stomach, and 0.80 (95% CI, 0.72-0.89) for colorectum. The cancer risk exhibited a slightly higher value for 10 years after quitting compared with continued smoking and then it decreased over time, reaching 50% of the risk associated with continued smoking after 15 or more years. Lung cancer risk decreased 3 years earlier than that of other cancer types, with a larger relative reduction. Regardless of quitting age, a significant reduction in the cancer risk was observed. Quitting before the age of 50 years was associated with a greater reduction in lung cancer risk (HR, 0.43; 95% CI, 0.35-0.53) compared with quitting at age 50 years or later (HR, 0.61; 95% CI, 0.56-0.66). Conclusions and Relevance: In this population-based retrospective cohort study, sustained smoking cessation was associated with significantly reduced risk of cancer after 10 years since quitting. Quitting at any age helped reduce the cancer risk, and especially for lung cancer, early cessation before middle age exhibited a substantial risk reduction.

Cost and effectiveness of the nationwide government-supported Smoking Cessation Clinics in the Republic of Korea.

OBJECTIVE: In the Republic of Korea, nationwide government-supported Smoking Cessation Clinics have been operating in 253 public health centres since 2004, but the cost and effectiveness of the service have yet to be evaluated. METHODS: The cost of the service (staff salary, medication, education and promotion and overhead) was calculated from the Smoking Cessation Clinic's 2009 financial report. The number of service users, self-reported 4-week and 6-month quit rates and the proportion of nicotine replacement therapy users were collected from the service's performance monitoring data. Long-term quit rate and life-years saved by quitting were estimated and used in addition to monitoring data to evaluate the effectiveness of the service. RESULTS: A total of 354 554 smokers used the Smoking Cessation Clinics in 2009. The self-reported 4-week and 6-month quit rates were 78% and 40%, respectively. Estimated 1-year and 8-year quit rates were 28.1% and 12.9%, respectively. The cost of the service in 2009 was US$21 127 thousand. Cost per service user who set a quit date was US$60. Cost per service user who maintained cessation at 4 weeks, 6 months and 1 year was US$76, US$149 and US$212, respectively. When considering 8-year quit rates, the cost per life-year saved was estimated at US$128 in the base scenario and increased to US$230 in the worst-case scenario. CONCLUSION: The nationwide government-supported public health centre-based Smoking Cessation Clinics provided highly cost-effective service at a level of 0.46% of the per capita gross domestic product.

Short-term effects of national smoking cessation service on smoking-related disease prevalence and healthcare costs: Experience from the National Health Insurance Service Smoking Cessation Intervention Program in Korea.

INTRODUCTION: We measured the short-term clinical and economic impacts of the National Health Insurance Service (NHIS) smoking cessation program, which subsidizes the cost of pharmacotherapy and medical consultations, by comparing the changes in prevalence and healthcare costs of smoking-related diseases among cessation service users, non-users, and never smokers. METHODS: Smokers who used the cessation service from 2015 to 2017 were included (n=779315). We used claims data from the NHIS, a mandatory, single-payer insurance covering the entire Korean population, to determine the number of patients with selected diseases, their healthcare utilization, and medical costs, and compared these amounts in the one year before and after enrollment. For further comparison, we also estimated disease prevalence and medical costs in matched controls by age, sex, income, and residential area, including never smokers and smokers who never used the cessation program. RESULTS: Across all 15 selected diseases, the number of patients, days spent in the hospital, and medical costs for 1 year were consistently higher after service enrollment than before. This pattern was observed for both men and women. Notably, decreased prevalence and medical costs for pneumonia were observed among individuals aged <50 years. Healthcare utilization for any kind of disease for 1 year was 97.7%, 91.1%, and 88.8% among cessation service users, never smokers, and smokers who did not use the cessation service, respectively. The disease-specific prevalence was also highest and increased more in the cessation service users compared with the control groups. CONCLUSIONS: Cessation service users were more likely to seek healthcare. Increased healthcare utilization in the first year after cessation service use may have resulted from smoking-related conditions that led individuals to attempt smoking cessation.

Impact of moderate-to-late preterm birth on neurodevelopmental outcomes in young children: Results from retrospective longitudinal follow-up with nationally representative data.

This study investigated the relationship between moderate-to-late preterm (MLPT) birth and the risk of neurodevelopmental impairments (NIs) in young children compared with the risks associated with very preterm (VPT) and full-term (FT) birth based on nationally representative large-scale population data. Retrospective follow-up was conducted over 71 months for 738,733 children who were born and participated in the Korean National Health Screening Program for Infants and Children (NHSPIC) between 2011 and 2013. Using a data linkage between the NHSPIC and Korean healthcare claim information, data on birth year, sex, delivery type, birth weight, growth abnormality, gestational age, breastfeeding history, maternal age, NIs, multiple gestation, preterm labor, premature rupture of membranes (PROM), gestational diabetes, gestational hypertension, smoking during pregnancy, and socioeconomic status were collected and included in the final analysis. Cox proportional hazards models were applied to identify the impact of gestational age on NI risk, with all variables adjusted as appropriate. Overall, 0.9% and 3.8% rates of VPT and MLPT births were identified, respectively. NI incidence was highest among VPT children (34.7%), followed by MLPT (23.9%) and FT (18.2%) children. Both VPT (hazard ratio [HR], 1.45; 95% confidence interval [CI], 1.03 to 2.05) and MLPT (HR, 1.21; 95% CI, 1.04 to 1.41) births were associated with increased NI risk. Low birth weight, PROM, and smoking during pregnancy were also associated with increased NI risk, while longer breastfeeding and higher socioeconomic status were associated with decreased risk. Special attention must be given to NIs for both VPT and MLPT children.

Association between Proinflammatory Cytokines and Lung Cancer Risk: A Case-Cohort Study from a Community-Based Prospective Cohort.

Recent studies have shed light on alterations to the proinflammatory tumor microenvironment as a significant carcinogenic mechanism. Despite previous studies on associations between proinflammatory cytokines and lung cancer risk, few studies have been conducted in Asian populations. This study aimed to investigate associations between proinflammatory cytokines and lung cancer risk, considering histological types, in the Korean general population. We carried out a case-cohort study on the Korean National Cancer Center Community (KNCCC) cohort (lung cancer cases: 136, subcohort: 822). Pre-diagnostic serum levels of proinflammatory cytokines (i.e., IL-6, TNF-α, IL-1ß, IFN-γ, and IL-10) were measured using Quantikine® ELISA. A Cox proportional-hazards regression analysis was conducted. In this study, serum levels of IL-6, IL-1ß, and IFN-γ were associated with lung cancer risk. IL-6 was associated with lung cancer, regardless of the histological type. IL-1ß had an association only with adenocarcinoma, while IFN-γ had an association only with squamous-cell carcinoma. This study shows associations between serum levels of IL-6, IL-1ß, and IFN-γ and lung cancer risk, underscoring the potential of these cytokines to act as risk biomarkers. The utilization of these biomarkers for risk prediction may hold the promise of facilitating the identification of the high-risk population.