BACKGROUND: Previous randomized controlled trials (RCTs) have reported inconsistent findings regarding the association between vitamin C supplementation and the risk of cancer. METHODS: We performed a meta-analysis of RCTs to investigate the efficacy of vitamin C supplements for prevention of cancer. We searched the PubMed, EMBASE, and Cochrane Library databases in November 2014 using common keywords related to vitamin C supplements and cancer. RESULTS: Among 785 articles, a total of seven trials were identified, which included 62,619 participants; 31,326 and 31,293 were randomized to vitamin C supplementation and control or placebo groups, respectively, which were included in the final analysis. A fixed-effects meta-analysis of all seven RCTs revealed no significant association between vitamin C supplementation and cancer (relative risk, 1.00; 95% confidence intervals, 0.95-1.05). Similarly, subgroup meta-analysis by dose of vitamin C administered singly or in combination with other supplements, follow-up period, methodological quality, cancer mortality, gender, smoking status, country, and type of cancer also showed no efficacy of vitamin C supplementation for cancer prevention. CONCLUSION: This meta-analysis shows that there is no evidence to support the use of vitamin C supplements for prevention of cancer.
Ascorbic Acid* ; Follow-Up Studies ; Mortality ; Smoke ; Smoking ; Vitamins*

BACKGROUND: Cigarette smoking is a risk factor for cardiovascular disease (CVD) and has both beneficial and harmful effects in CVD. We hypothesized that weight gain following smoking cessation does not attenuate the CVD mortality of smoking cessation in the general Korean population. METHODS: Study subjects comprised 2.2% randomly selected patients from the Korean National Health Insurance Corporation, between 2002 and 2013. We identified 61,055 subjects who were classified as current smokers in 2003–2004. After excluding 21,956 subjects for missing data, we studied 30,004 subjects. We divided the 9,095 ex-smokers into two groups: those who gained over 2 kg (2,714), and those who did not gain over 2 kg (6,381, including weight loss), after smoking cessation. Cox proportional hazards regression models were used to estimate the association between weight gain following smoking cessation and CVD mortality. RESULTS: In the primary analysis, the hazard ratios of all-cause deaths and CVD deaths were assessed in the three groups. The CVD risk factors and Charlson comorbidity index adjusted hazard ratios (aHRs) for CVD deaths were 0.80 (95% confidence interval [CI], 0.37 to 1.75) for ex-smokers with weight gain and 0.80 (95% CI, 0.50 to 1.27) for ex-smokers with no weight gain, compared to one for sustained smokers. The associations were stronger for events other than mortality. The aHRs for CVD events were 0.69 (95% CI, 0.54 to 0.88) and 0.81 (95% CI, 0.70 to 0.94) for the ex-smokers with and without weight gain, respectively. CONCLUSION: Although smoking cessation leads to weight gain, it does not increase the risk of CVD death.
Cardiovascular Diseases* ; Comorbidity ; Humans ; Mortality ; National Health Programs ; Risk Factors ; Smoke* ; Smoking Cessation* ; Smoking* ; Weight Gain

BACKGROUND: Smoking is one of the known major risk factors of coronary artery disease and previous studies have shown that the risk of mortality declines after cessation of smoking. The goal of this study was to determine the influence of smoking on mortality after percutaneous coronary intervention, which has still not been established in Korea. METHODS: Patients who had undergone successful percutaneous coronary intervention at Asan Medical Center between January 1996 and June 1997 were classified into nonsmokers (n=306), ex-smokers (n=178), and current smokers (n=360). According to subsequent smoking status, current smokers were divided into quitters (n=152), persistent smokers (n=173), and unknown status (n=35). The data of the death Roll was from the National Statistical Office. RESULTS: The maximum follow-up was 119 months (mean+/-SD=100+/-26.5). The total smoking rate was 42.7%. The mortality rates of nonsmokers, ex-smokers and current smokers were 17.6%, 20.8%, and 17.2%, respectively. In analyses adjusted for base line characteristics, the relative risk of death among current smokers was 1.57 (95% confidence interval [CI], 0.98 to 2.53) and among ex-smokers was 1.37 (95% CI, 0.80 to 2.35) compared with nonsmokers. The persistent smokers had a greater relative risk of death from all causes (relative risk, 2.20 [95% CI, 1.08 to 4.48]) as compared with the quitters. CONCLUSION: The persistent smokers were at greater risk for death than the quitters. Therefore, patients undergoing percutaneous intervention should be encouraged to stop smoking.
Chungcheongnam-do ; Coronary Artery Disease ; Follow-Up Studies ; Humans ; Korea ; Mortality* ; Percutaneous Coronary Intervention* ; Risk Factors ; Smoke* ; Smoking Cessation* ; Smoking*

Lung cancer became a leading cause of cancer deaths in Korea in 2000. It is an anticipated result of cigarette smoking which was very prevalent among Korean males over the past several decades. There were 10,230 new reported cases of lung cancer in 2000 and the lung cancer mortality rate was 25.0 per 100,000 persons in 2001. Despite better supportive care and improved surgical techniques and development of more effective chemotherapeutic agents, the outcome of lung cancer patients in Korea remains disappointingly poor with a 5-year relative survival rate of only 11.4%. One of the major reasons for this poor outcome is that only approximately one-fifth of lung cancer are diagnosed at early resectable stages and benefited from curative surgery while the majority of patients have their tumors found at more advanced stages. Unfortunately, there is no established means for early lung cancer detection and screening program. Smoking cessation is the one and only known effective means of lung cancer prevention. In order to curtail the ever-rising incidence and mortality of lung cancer in Korea, it is mandatory to launch an even more strong anti-smoking campaign and utilize all means to discourage teen-ager smoking. In addition, there should be more support from both industry and the government for the development of more effective chemotherapy and new molecular-targeted therapeutic agents and establishment of infrastructures for clinical trials. A new effective treatment for lung cancer can be established only through the scrutiny of well-designed clinical trials.
Drug Therapy ; Humans ; Incidence ; Korea ; Lung Neoplasms* ; Lung* ; Male ; Mass Screening ; Mortality ; Smoke ; Smoking ; Smoking Cessation ; Survival Rate

Schizophrenia is a major chronic mental illness with various symptoms that is often accompanied by substance use disorders. Patients with schizophrenia have a higher smoking rate than the general population and a lower smoking cessation success rate. Further, their motivation for smoking cessation is often low. Individuals with schizophrenia that are past or present cigarette smokers are more difficult to treat in terms of psychotic symptoms, are more likely to have physical illnesses, and have higher mortality rates. A variety of treatments, both pharmacological and non-pharmacological, are used to aid smoking cessation in patients with schizophrenia. Among these, bupropion, varenicline, and nicotine replacement therapy can be safely used in patients with schizophrenia, and several studies have demonstrated their effects. Cigarette smoking is an important health problem. The study of smoking cessation in individuals with schizophrenia may help improve their ability to function and their quality of life through active evaluation and treatment.
Bupropion ; Drug Therapy ; Humans ; Mortality ; Motivation ; Nicotine ; Quality of Life ; Schizophrenia ; Smoke ; Smoking Cessation ; Smoking ; Substance-Related Disorders ; Tobacco Products ; Varenicline

Using a cross-sectional representative national survey, we evaluated the relationship between cigarette smoking and unintentional injuries among Korean adults. We used data from the 2009 Korean Community Health Survey. Smoking status was defined as never smokers, ex-smokers, and current smokers. Current smokers were categorized into light daily smokers (1–10 cigarettes/day), moderate daily smokers (11–20 cigarettes/day), or heavy daily smokers (≥21 cigarettes/day). We used the Poisson regression model with a robust variance estimation to estimate prevalence rate ratios (PRR) and corresponding 95% confidence interval (95% CI). After adjusting for demographic characteristics, socioeconomic variables, lifestyle variables, and health status variables, former smokers (PRR, 1.19, 95% CI 1.11–1.28), light daily smokers (PRR 1.22, 95% CI 1.13–1.32), moderate daily smokers (PRR 1.33, 95% CI 1.24–1.42), and heavy daily smokers (PRR 1.40, 95% CI 1.25–1.57) had an increased risk for unintentional injuries compared with non-smokers. In conclusion, cigarette smoking is associated with unintentional injuries in a dose-response manner in Korean adults. The findings suggest that community smoking cessation programs may reduce morbidity and mortality from unintentional injuries.
Adult* ; Cross-Sectional Studies ; Health Surveys ; Humans ; Life Style ; Mortality ; Prevalence ; Public Health ; Smoke* ; Smoking Cessation ; Smoking*

OBJECTIVETo prospective examine the relationship between smoking, quitting and mortality in older Chinese men by in Xi'an, China.

METHODSThe design was a cohort analytic study. One thousand two hundred and sixty-eight retired male military veterans aged 60 or older were examined in 1987. At baseline, there were 388 never-smokers, 461 former smokers and 419 current smokers. Main outcome measure was all-cause and tobacco-associated mortality.

RESULTSThrough 1999, 299 had died, 943 were alive and 26 lost. The mean follow-up time was 11 years and total person-year of follow-up was 14 163. After adjusting for age, blood pressure, body mass index, total cholesterol, triglycerides, alcohol intake, exercise and existing diseases, using Cox proportional hazard regression model, the relative risks (95% confidence intervals) for ever-smoking, deaths resulting from all causes, chronic obstructive pulmonary disease (COPD), lung cancer and coronary heart disease (CHD) were 1.34 (1.02 - 1.76), 3.23 (0.95 - 10.91), 2.31 (0.95 - 5.61) and 1.60 (0.81 - 3.19) respectively. The risks increased significantly with increasing amount and duration of smoking. Compared with current smokers, former smokers had lower risks of total mortality (excess risk reduction of 56%) and from CHD death (93%), but had higher risks for COPD death (excess risk increased 174%).

CONCLUSIONSSmoking is a major cause of death in older Chinese men and quitting can save lives. These results showing that higher risks of COPD death in former smokers with or without existing diagnosed COPD at baseline than those in current smokers could be explained by either the "healthy smoker effect" or the "ill quitter effect" or both. Early recognition of the significance of COPD symptoms followed by prompt quitting should be emphasized as strategies in the control of the growing tobacco epidemic.

Aged ; China ; Cohort Studies ; Coronary Disease ; etiology ; mortality ; Humans ; Lung Neoplasms ; etiology ; mortality ; Male ; Middle Aged ; Prospective Studies ; Pulmonary Disease, Chronic Obstructive ; etiology ; mortality ; Risk Factors ; Smoking ; adverse effects ; mortality ; Smoking Cessation ; Survival Rate ; Veterans

The purpose of this study was to identify and measure the economic costs and benefits due to smoking in Korea. Cigarette smoking is a major cause of morbidity and mortality. In addition to the health risks of smoking, there are important economic consequences. A complete assessment of the economics of smoking requires evaluation of various health, economic, and intangible parameters, including benefits as well as costs of both the production and consumption of tobacco. In this article we focus on costs resulting from the health effects of smoking (expenditures for medical care and the value of productive output lost to morbidity, and premature mortality among smokers), since economic benefits from tobacco industry is offset by expenditures for purchasing tobacco. Two distinct methodologies will be applied to measure the economic costs of smoking cigarette, the human capital and willingness-to-pay approaches. This article used the former method. In 1985, total economic losses due to smoking was estimated as 505.7 billion won, which was composed of morbidity losses 64.9 billion won, mortality losses 429.1 billion won and indirect costs 11.7 billion won.
Cost-Benefit Analysis ; Health Expenditures ; Humans ; Korea ; Mortality ; Mortality, Premature ; Smoke* ; Smoking* ; Tobacco ; Tobacco Industry ; Tobacco Products

BACKGROUNDSmoking is known to be a strong risk factor for premature atherosclerosis, acute myocardial infarction (AMI) and sudden cardiac death. According to a cross-sectional survey conducted in 2000 - 2001 in China, the prevalence of smoking among the Chinese men was 60.2%, the highest prevalence in the world. Up to date, the relationship between smoking and AMI in Chinese male smokers is still unclear. This study analyzed the baseline characteristics for male smokers hospitalized with AMI and investigated the effect of cigarette smoking on their clinical outcomes.

METHODSA total of 890 men aged 18 years or over with AMI were prospectively recruited from 1 January 2007 to 31 December 2009 from Shanxi Provincial People's Hospital. Patients were grouped into smokers and nonsmokers. The relationships between baseline characteristics and clinical outcomes were tested using either the chi-square test for trend for discrete variables or analysis of variance for continuous variables.

RESULTSSmokers accounted for 66.7% (594), more than twice of nonsmokers (296 (33.3%)), and were averaged 7 years younger ((56.61 ± 11.44) vs. (63.61 ± 11.62) years, P < 0.001). Smokers had the higher rate of TIMI flow grade 2 or 3 after thrombolytic therapy (42.4% vs. 24.5%, P = 0.002), 1 vessel disease (25.5% vs. 14.5%, P = 0.003) than nonsmokers. Smokers had better in-hospital outcome with lower in-hospital mortality rate than nonsmokers (6.2% vs. 10.8%, P = 0.023).

CONCLUSIONSMale smokers suffered from AMI in this study presented an average of 7 years earlier than nonsmokers and were more than twice as likely to have AMI as nonsmokers in China. Smoking appeared to result in earlier infarction, especially ST elevated myocardial infarction in otherwise healthier patients who are likely to survive.

Acute Disease ; Adult ; Aged ; China ; Hospital Mortality ; Hospitalization ; Humans ; Male ; Middle Aged ; Myocardial Infarction ; mortality ; Smoking ; adverse effects

BACKGROUND: Obesity and decreased pulmonary function increase mortality and morbidity of diseases. Obesity is a major factor of decreased pulmonary function. There are variable results of how much body mass index (BMI) and body fat percent influence pulmonary function. There arefew data between obesity and pulmonary function in Korea. This study observed the association of BMI, body fat percent and pulmonary function, and quantified the impact of obesity to pulmonary function. METHODS: 603, non-smoking women in their forbles visited the Health Promotion Center of Inha University Hospital from January 3, 2000 to December 31 2000. Questions concerning smoking, exercise, and past medical history were made. Body fat percent and pulmonary function were measured. Correlation, simple linear regression and multiple linear regression between obesity indices and pulmonary function were used executed. RESULTS: BMI has no correlation with FVC, FEV1 and FEV1/FVC ratio. Body fat percent was negatively correlated with FVC and FEV1 (r=-0.162; P<0.01, r= -0.195; P<0.01), and was not correlated with FEV1/FVC ratio. In a multiple linar regression, body fat percent was inversely related to FVC and FEV1 (beta=-10.380; P<0.01, beta=-11.379; P<0.01). CONCLUSION: Increased body fat percent has association with decreased pulmonary function and has more impact on FEV1 than FVC. FVC was decreased by 10.380 mL and FEV1 was decreased by 11.379 mL when body fat percent increased by 1%.
Adipose Tissue* ; Body Mass Index* ; Female ; Health Promotion ; Humans ; Korea ; Linear Models ; Mortality ; Obesity ; Smoke ; Smoking