Higher cholesterol levels, not statin use, are associated with a lower risk of hepatocellular carcinoma.

We aimed to examine whether statin users have a lower risk of hepatocellular carcinoma (HCC) after careful consideration of prevalent statin use and cholesterol levels. During a mean prospective follow-up of 8.4 years in 400,318 Koreans, 1686 individuals were diagnosed with HCC. When prevalent users were included, HCC risk was reduced by >50% in statin users, regardless of adjustment for total cholesterol (TC). When prevalent users were excluded, new users who initiated statins within 6 months after baseline had a 40% lower risk of HCC (hazard ratio [HR] = 0.59) in a TC-unadjusted analysis. However, this relationship disappeared (HR = 1.16, 95% CI = 0.80-1.69) after adjusting for TC levels measured within 6 months before statin initiation. TC levels had strong inverse associations with HCC in each model. High cholesterol levels at statin initiation, not statin use, were associated with reduced risk of HCC. Our study suggests no protective effect of statins against HCC.

Low Systolic Blood Pressure and Vascular Mortality Among More Than 1 Million Korean Adults.

BACKGROUND: The association between low systolic blood pressure (SBP) and vascular disease is unclear, especially in nonclinical populations. METHODS AND RESULTS: We studied 1 235 246 individuals who participated in routine medical examinations between 1992 and 1995. The hazard ratios (HRs) were adjusted for potential confounders. During 22.7 million person-years of follow-up, 34 816 individuals died of atherosclerotic vascular diseases. An increase in SBP was directly related to an increase in vascular mortality at SBP above ≈100 mmHg. The group with the lowest SBP (<90 mm Hg) had a higher HR for mortality from atherosclerotic vascular disease (HR, 1.53; 95% confidence interval, 1.15-2.03) in comparison with those with an SBP of 90 to 99 mm Hg. The HR associated with the lowest SBP was 2.54 (95% confidence interval, 1.51-4.29) for ischemic heart disease and 1.21 (95% confidence interval, 0.79-1.85) for stroke. Regarding stroke subtype, mortality from hemorrhagic stroke (HR per 10 mm Hg increase, 0.53; 95% confidence interval, 0.29-0.96), rather than mortality from ischemic stroke (HR per 10 mm Hg increase, 1.00; 95% confidence interval, 0.51-1.97), was inversely associated with SBP when SBP fell to <100 mm Hg. Even when excluding the first 5 years of follow-up, the HRs associated with the lowest SBP did not decrease. The inverse association between SBP and vascular mortality in the range <100 mm Hg tended to be apparent in people aged 60 to 95 years in comparison with individuals aged 30 to 59 years. CONCLUSIONS: J-curve associations exist between SBP and vascular mortality, which reach a nadir at ≈100 mm Hg. SBP of <90 mm Hg may portend death from vascular disease, particularly from ischemic heart disease.

Agent Orange exposure and cancer incidence in Korean Vietnam veterans: a prospective cohort study.

BACKGROUND: During the Vietnam War, US and allied military sprayed approximately 77 million liters of tactical herbicides including Agent Orange, contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin. To the authors' knowledge, few studies to date have examined the association between Agent Orange exposure and cancer incidence among Korean veterans who were exposed to Agent Orange during the Vietnam War. METHODS: An Agent Orange exposure index, based on the proximity of the veteran's military unit to the area that was sprayed with Agent Orange, was developed using a geographic information system-based model. Cancer incidence was followed for 180,251 Vietnam veterans from 1992 through 2003. RESULTS: After adjustment for age and military rank, high exposure to Agent Orange was found to significantly increase the risk of all cancers combined (adjusted hazards ratio [aHR], 1.08). Risks for cancers of the mouth (aHR, 2.54), salivary glands (aHR, 6.96), stomach (aHR, 1.14), and small intestine (aHR, 2.30) were found to be significantly higher in the high-exposure group compared with the low-exposure group. Risks for cancers of all sites combined (aHR, 1.02) and for cancers of the salivary glands (aHR, 1.47), stomach (aHR, 1.03), small intestine (aHR, 1.24), and liver (aHR, 1.02) were elevated with a 1-unit increase in the exposure index. CONCLUSIONS: Exposure to Agent Orange several decades earlier may increase the risk of cancers in all sites combined, as well as several specific cancers, among Korean veterans of the Vietnam War, including some cancers that were not found to be clearly associated with exposure to Agent Orange in previous cohort studies primarily based on Western populations.

Agent Orange exposure and disease prevalence in Korean Vietnam veterans: the Korean veterans health study.

Between 1961 and 1971, military herbicides were used by the United States and allied forces for military purposes. Agent Orange, the most-used herbicide, was a mixture of 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid, and contained an impurity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Many Korean Vietnam veterans were exposed to Agent Orange during the Vietnam War. The aim of this study was to evaluate the association between Agent Orange exposure and the prevalence of diseases of the endocrine, nervous, circulatory, respiratory, and digestive systems. The Agent Orange exposure was assessed by a geographic information system-based model. A total of 111,726 Korean Vietnam veterans were analyzed for prevalence using the Korea National Health Insurance claims data from January 2000 to September 2005. After adjusting for covariates, the high exposure group had modestly elevated odds ratios (ORs) for endocrine diseases combined and neurologic diseases combined. The adjusted ORs were significantly higher in the high exposure group than in the low exposure group for hypothyroidism (OR=1.13), autoimmune thyroiditis (OR=1.93), diabetes mellitus (OR=1.04), other endocrine gland disorders including pituitary gland disorders (OR=1.43), amyloidosis (OR=3.02), systemic atrophies affecting the nervous system including spinal muscular atrophy (OR=1.27), Alzheimer disease (OR=1.64), peripheral polyneuropathies (OR=1.09), angina pectoris (OR=1.04), stroke (OR=1.09), chronic obstructive pulmonary diseases (COPD) including chronic bronchitis (OR=1.05) and bronchiectasis (OR=1.16), asthma (OR=1.04), peptic ulcer (OR=1.03), and liver cirrhosis (OR=1.08). In conclusion, Agent Orange exposure increased the prevalence of endocrine disorders, especially in the thyroid and pituitary gland; various neurologic diseases; COPD; and liver cirrhosis. Overall, this study suggests that Agent Orange/2,4-D/TCDD exposure several decades earlier may increase morbidity from various diseases, some of which have rarely been explored in previous epidemiologic studies.

Lung Cancer Risk Prediction Models for Asian Ever-Smokers.

INTRODUCTION: Although lung cancer prediction models are widely used to support risk-based screening, their performance outside Western populations remains uncertain. This study aims to evaluate the performance of 11 existing risk prediction models in multiple Asian populations and to refit prediction models for Asians. METHODS: In a pooled analysis of 186,458 Asian ever-smokers from 19 prospective cohorts, we assessed calibration (expected-to-observed ratio) and discrimination (area under the receiver operating characteristic curve [AUC]) for each model. In addition, we developed the "Shanghai models" to better refine risk models for Asians on the basis of two well-characterized population-based prospective cohorts and externally validated them in other Asian cohorts. RESULTS: Among the 11 models, the Lung Cancer Death Risk Assessment Tool yielded the highest AUC (AUC [95% confidence interval (CI)] = 0.71 [0.67-0.74] for lung cancer death and 0.69 [0.67-0.72] for lung cancer incidence) and the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial Model had good calibration overall (expected-to-observed ratio [95% CI] = 1.06 [0.90-1.25]). Nevertheless, these models substantially underestimated lung cancer risk among Asians who reported less than 10 smoking pack-years or stopped smoking more than or equal to 20 years ago. The Shanghai models were found to have marginal improvement overall in discrimination (AUC [95% CI] = 0.72 [0.69-0.74] for lung cancer death and 0.70 [0.67-0.72] for lung cancer incidence) but consistently outperformed the selected Western models among low-intensity smokers and long-term quitters. CONCLUSIONS: The Shanghai models had comparable performance overall to the best existing models, but they improved much in predicting the lung cancer risk of low-intensity smokers and long-term quitters in Asia.

Physical activity level and risk of death: the severance cohort study.

BACKGROUND: Physical activity decreases deaths from cardiovascular disease and other causes; however, it is unclear whether physical activity is associated with cancer incidence and death in Asian populations. METHODS: Data from 59 636 Koreans aged 30 to 93 years were collected using a questionnaire and medical examination at the Severance Hospital Health Promotion Center between 1994 and 2004. Study participants were followed for a mean duration of 10.3 years. RESULTS: In the exercising group, the multivariate Cox proportional hazards model showed a lower risk of cancer death (hazard ratio [HR] = 0.72, 95% CI = 0.62-0.85) in men but not in women. Those who exercised, as compared with those who did not, had lower risks of all-cause death (men: HR = 0.68, 95% CI = 0.60-0.76; women: HR = 0.65, 95% CI = 0.53-0.79) and noncancer death (men: 0.63, 0.53-0.75; women: 0.52, 0.39-0.69). Physical activity was inversely associated with risk of noncancer death among men and women. CONCLUSIONS: Physical activity was associated with lower risks of cancer death and noncancer death.

Life satisfaction and mortality in elderly people: the Kangwha Cohort Study.

BACKGROUND: As well as biomedical risk factors, psychological factors have been reported to be related to mortality rate. The purpose of this study was to examine the relationship between life satisfaction and mortality in elderly people through an 11.8-year follow-up study of a prospective cohort. METHODS: Among 3,600 participants of the Kangwha Cohort Study who survived in 1994, 1,939 respondents of the Life Satisfaction Index (LSI)-A questionnaire were included (men, 821; women, 1118). The mortality risk for the period up to December 2005 was measured using the Cox Proportional Hazard Model. RESULTS: When the relationship between LSI and mortality was evaluated in men, the unsatisfied group with lower LSI scores showed a significantly higher risk of all-cause mortality (hazard ratio [HR], 1.42; 95% confidence interval [CI], 1.11-1.83) than the satisfied group with higher LSI scores. In women, the unsatisfied group showed a significantly higher risk of all-cause mortality (HR, 1.51; 95% CI, 1.18-1.92) and cardiovascular mortality (HR, 2.23; 95% CI, 1.30-3.85) than the satisfied group. CONCLUSION: We found that elderly people with a lower LSI score, regardless of gender, were at risk of increased mortality from all causes, and low LSI score was also associated with cardiovascular mortality.

Association between low-density lipoprotein cholesterol and cardiovascular mortality in statin non-users: a prospective cohort study in 14.9 million Korean adults.

BACKGROUND: Limited information is available on detailed sex/age-specific associations between low-density lipoprotein cholesterol (LDL-C) and cardiovascular disease (CVD) mortality and 'the optimal range' associated with the lowest CVD mortality in the general population. METHODS: Korean adults (N = 14 884 975) who received routine health screenings during 2009-2010 were followed until 2018 for CVD mortality. RESULTS: During 8.8 years (mean) of follow-up, 94 344 individuals died from CVD. LDL-C had U-curve associations with mortality from CVD and its subtypes, except haemorrhagic stroke. Optimal range was 90-149 mg/dL for CVD; 70-114 for ischaemic heart disease; 85-129 for ischaemic stroke; ≥85 for subarachnoid haemorrhage; ≥130 for intracerebral haemorrhage; 115-159 for hypertension and heart failure; and 100-144 for sudden cardiac death. Assuming linear associations between 100 and 300 mg/dL, LDL-C was positively associated with CVD mortality [hazard ratio (HR) per 39-mg/dL (1-mmol/L) higher LDL-C = 1.10], largely due to ischaemic heart disease (HR = 1.26), followed by sudden cardiac death (HR = 1.13), ischaemic stroke (HR = 1.11) and heart failure (HR = 1.05). Intracerebral haemorrhage (HR = 0.90), but not subarachnoid haemorrhage, had inverse associations. Women and older adults had weaker positive associations than men and younger adults (Pinteraction < 0.001 for both sex and age). Individuals aged 75-84 years had modest positive associations with CVD mortality, especially ischaemic heart disease and ischaemic stroke. CONCLUSION: LDL-C had U-curve associations for CVD mortality. The associations and optimal ranges differed across CVD subtypes. Women and older adults had weaker positive associations than men and younger adults. Positive associations with ischaemic heart disease and ischaemic stroke were maintained in adults aged 75-84 years.

High-density lipoprotein cholesterol and cardiovascular mortality: a prospective cohort study among 15.8 million adults.

AIMS: We aimed to investigate whether the associations between high-density lipoprotein cholesterol (HDL-C) and cardiovascular disease (CVD) mortality and the optimal range differ by age and CVD subtypes. METHODS AND RESULTS: Korean adults (n = 15 859 501) with no CVD/cancer who received routine health examinations during 2009-2010 were followed until 2018 for CVD mortality. During a mean 8.8 years of follow-up, 108 123 individuals died from CVD. U-curve associations were found between HDL-C and CVD mortality, regardless of sex, age, and CVD subtype. The optimal range was 50-79 mg/dL (1.29-2.06 mmol/L), while it was 40-69 (1.03-1.80), 50-79 (1.29-2.06), and 60-89 (1.55-2.32) mg/dL (mmol/L) in adults aged <45 years, 45-64 years, and 65-99 years, respectively. Assuming linear associations <60 mg/dL, the multivariable-adjusted hazard ratios (HRs) per 39 mg/dL (1 mmol/L) higher level were 0.58 (95% confidence interval = 0.56-0.60), and they were 0.61 (0.52-0.72), 0.58 (0.54-0.62), and 0.59 (0.56-0.61) in individuals aged 18-44, 45-64, and 65-99 years, respectively [Pinteraction (age) = 0.845]. Assuming linear associations in the 60-150 mg/dL range, HDL-C was positively associated with CVD mortality (HR = 1.09, 1.04-1.14). The strongest association was for sudden cardiac death (SCD) (HR = 1.37), followed by heart failure (HF) (HR = 1.20) and intracerebral haemorrhage (ICH) (HR = 1.13). The HRs were 1.47 (1.23-1.76), 1.17 (1.08-1.28), and 1.03 (0.97-1.08) in individuals aged 18-44, 45-64, and 65-99 years, respectively [Pinteraction (age) < 0.001]. CONCLUSION: Both low and high levels of HDL-C were associated with increased mortality from CVD in the general population, especially SCD, HF, and ICH. High HDL-C levels are not necessarily a sign of good cardiovascular health, especially in younger adults.

Combined effects of cognitive impairment and hypertension on total mortality in elderly people: the Kangwha Cohort study.

BACKGROUND: Previous studies have shown links between cognitive impairment and hypertension as well as mortality. However, combined effects of these two conditions on mortality have not been fully explored. OBJECTIVE: To assess the combined effect of cognitive impairment and hypertension on all-cause mortality among the elderly people. METHODS: We followed a cohort of 2,496 residents in Kangwha County, ranging in age from 64 to 101 years as of March 1994, for all-cause mortality for 11.8 years up to December 31, 2005. We calculated hazard ratios (HR) for all-cause mortality by cognitive status and blood pressure using the Cox proportional hazards model after having controlled for confounding factors. RESULTS: 1,189 people (47.6%) died during the 11.8 years of follow-up. The HR associated with severe cognitive impairment increased from 2.15 (95% CI: 1.30, 3.54) for prehypertension over 2.68 (95% CI: 1.60, 4.48) for stage 1 hypertension to 3.60 (95% CI: 1.99, 6.49) for stage 2 hypertension in women. A mortality risk of 3.67 (95% CI: 2.05, 6.57) was observed among men who had both mild cognitive impairment and stage 2 hypertension. CONCLUSION: Individuals with coexisting cognitive impairment and hypertension are at an increased risk of all-cause mortality compared with those with cognitive impairment or hypertension alone.

Immunizing children aged 9 to 15 months with live attenuated SA14-14-2 Japanese encephalitis vaccine in Thailand.

The authors aimed to evaluate the safety and immunogenicity of a live attenuated SA14-14-2 Japanese Encephalitis (JE) vaccine in healthy Thai infants. One hundred and fifty subjects aged 9-15 months were vaccinated with one dose of this vaccine. Regarding the vaccine safety, during the 28-day post-vaccination follow-up, no vaccine-related serious adverse events were reported. In terms of immunogenicity, the sero-conversion rate of a single dose vaccination was 95% (95% CI, 90.0-97.6%) within 90 days after vaccination and the geometric mean titer (GMT) was 66.1. Eight subjects with JE seronegative on days 28-35 post-vaccination became sero-positive on day 90. Seven subjects who remained sero-negative during days 28-35 and day 90 post-vaccination were successfully sero-converted after receiving a second dose 3 months later. Thus, two doses of this JE vaccine resulted in a 100% (95% CI, 97.3-100%) sero-conversion rate with the GMT of 260.8. Eight children with GMTs lower than protective level after a single vaccination demonstrated a booster response with GMT of 1237 after the second dose of JE vaccination. In conclusion, the live attenuated SA14-14-2 vaccine was safe, well tolerated and highly immunogenic with 95% and 100% sero-conversion rate after one and two doses, respectively. Nevertheless, its long-term immune response and possible influences from natural dengue infection requires further evaluation.

High-density lipoprotein cholesterol and all-cause mortality by sex and age: a prospective cohort study among 15.8 million adults.

BACKGROUND: The associations between high-density lipoprotein cholesterol (HDL-C) levels and all-cause mortality are unclear in young adults (<45 years) and in Asian populations. METHODS: In total, 15 860 253 Korean adults underwent routine health examinations during 2009-10 and were followed until June 2018 for all-cause mortality. Hazard ratios (HRs) were calculated using Cox proportional hazard models. RESULTS: During a mean 8.4 years of follow-up, 555 802 individuals died. U-curve associations were found between HDL-C levels and mortality, irrespective of sex or age. The HDL-C ranges associated with the lowest mortality were 40-59 and 50-69 mg/dL (1.03-1.54 and 1.29-1.80 mmol/L) in men aged <65 and ≥65 years, respectively, and the corresponding ranges were 40-69 and 50-79 mg/dL (1.03-1.80 and 1.29-2.06 mmol/L) in women aged <45 and ≥45 years, respectively. For HDL-C ranges of 60-149 mg/dL (1.55-3.86 mmol/L), each 39 mg/dL (1 mmol/L) increase in HDL-C was associated with higher mortality [men: HR = 1.39; 95% confidence interval (CI) = 1.36-1.42; women: HR = 1.15, 95% CI = 1.11-1.18], adjusting for age. These positive associations were generally stronger at younger than older ages, whereas inverse associations for HDL-C ranges <60 mg/dL (1.55 mmol/L) were strongest in middle age (45-64 years). The U-curve associations were generally unchanged after adjustment for various confounders. CONCLUSIONS: Korean adults showed U-curve associations of HDL-C with mortality, regardless of sex, and age. Younger adults had a lower optimal range and a stronger positive association with mortality than older adults in the high HDL-C range. Even moderately high HDL-C levels are not necessarily a sign of good health, especially in young adults.

Binge drinking and hypertension on cardiovascular disease mortality in Korean men and women: a Kangwha cohort study.

BACKGROUND AND PURPOSE: The purpose of this study was to examine combined effects of hypertension and binge drinking on the risk of mortality from cardiovascular disease in Koreans. METHODS: This study followed a cohort of 6100 residents in Kangwha County, aged ≥55 years as of March 1985, for cardiovascular mortality for 20.8 years up to December 31, 2005. We calculated hazard ratios (HRs) for cardiovascular mortality by blood pressure and binge drinking habits using the Cox proportional hazard model. Binge drinkers and heavy binge drinkers were defined as having ≥6 drinks on 1 occasion and ≥12 drinks on 1 occasion. RESULTS: After adjusting for total alcohol consumption, male heavy binge drinkers with Grade 3 hypertension had a 12-fold increased risk of cardiovascular mortality (HR, 12.7; 95% CI, 3.47 to 46.5), whereas male binge drinkers with Grade 3 hypertension had a 4-fold increased risk of cardiovascular mortality (HR, 4.41; 95% CI, 1.38 to 14.1) when compared with nondrinkers with normal blood pressure. However, in considering separate effects of heavy binge drinking and hypertension on the risk of cardiovascular mortality, HRs were rather low (HR of heavy binge drinkers, 1.88, 1.10 to 3.20; HR of hypertensives, 2.00, 1.70 to 2.35) compared with nondrinkers with normal blood pressure. CONCLUSIONS: Binge drinkers and heavy binge drinkers with Grade 3 hypertension showed a marked increase in cardiovascular mortality risk. Even after adjusting for total alcohol consumption, the former revealed 4.41 and the latter indicated 12.7 of HR for the risk of cardiovascular mortality.

Alcohol consumption and digestive cancer mortality in Koreans: the Kangwha Cohort Study.

BACKGROUND: Alcohol consumption is a known risk factor for cancers of the mouth, esophagus, liver, colon, and breast. In this study, we examined the association between alcohol consumption and digestive cancer mortality in Korean men and women. METHODS: A cohort of 6291 residents of Kangwha County who were aged 55 years or older in March 1985 were followed to 31 December 2005-a period of 20.8 years. We calculated the relative risks of cancer mortality with respect to the amount of alcohol consumed. Cox proportional hazard model was used to adjust for age at entry, smoking, ginseng intake, education status, and pesticide use. RESULTS: In men, the risks of mortality from esophageal cancer (relative risk [RR], 5.62; 95% confidence interval [CI], 1.45-21.77) and colon cancer (RR, 4.59; 95% CI, 1.10-19.2) were higher among heavy drinkers, as compared with abstainers. The risks of mortality from colon cancer and bile duct cancer rose with increasing alcohol consumption; these trends were positive and statistically significant (P = 0.04 and P = 0.02, respectively). When participants were stratified by type of alcoholic beverage, soju drinkers had higher risks of mortality from esophageal cancer and colon cancer than makkoli drinkers. In women, the risk of digestive cancer mortality was higher among alcohol drinkers than abstainers, but this difference was not statistically significant. CONCLUSIONS: Alcohol consumption increases mortality from esophageal cancer and colon cancer in men.

Binge drinking and mortality from all causes and cerebrovascular diseases in korean men and women: a Kangwha cohort study.

BACKGROUND AND PURPOSE: The purpose of this study was to examine the association between binge drinking and risks of mortality due to all causes of death with a focus on cerebrovascular disease in Korean men and women. METHODS: This study followed a cohort of 6291 residents in Kangwha County, aged > or =55 years in March 1985, for their cause-specific mortality for 20.8 years up to December 31, 2005. We calculated hazard ratio of mortality by experience or frequency of binge drinking using the Cox proportional hazard model. Binge drinking was defined as having > or =6 drinks on one occasion. RESULTS: In men, binge drinkers who drink daily had an increased risk of mortality from all causes (hazard ratio, 1.33; 95% CI, 1.11 to 1.60) as compared with nondrinkers. They showed much increased risks of mortality from total stroke (hazard ratio, 1.86; 95% CI, 1.16 to 2.99) and hemorrhagic stroke (hazard ratio, 3.39; 95% CI, 1.38 to 8.35). Female binge drinkers also showed an increased risk of mortality from cardiovascular disease as compared with female nondrinkers, but the outcome was not statistically significant. CONCLUSIONS: The results of this study suggest that frequent binge drinking has a harmful effect on hemorrhagic stroke in Korean men. These findings need to be confirmed in further studies.

Body mass index and stroke mortality by smoking and age at menopause among Korean postmenopausal women.

BACKGROUND AND PURPOSE: The association between body mass index and mortality caused by subtypes of stroke among postmenopausal women in terms of smoking status and age at menopause remains controversial. METHODS: The data were derived from a cohort study of 3321 with 17.8 years of follow-up (1985 to 2002). Hazard ratios (HRs) and 95% CIs for strokes as related to body mass index were estimated by Cox proportional hazard models adjusted for age, hypertension, smoking, drinking, occupation, education, self-reported health, and age at menopause. A stratified analysis was conducted by age at menopause and smoking status. RESULTS: The obese group (body mass index >or=27.5 kg/m(2)) had higher risks of total stroke mortality (HR, 1.59; 95% CI, 1.05 to 2.42) and hemorrhagic stroke mortality (HR, 2.91; 95% CI, 1.37 to 6.19) than the normal weight group (18.5or=50. For the obese group of the former, the HR of total stroke was 2.04 (95% CI, 1.25 to 3.34) and that of hemorrhagic stroke 6.46 (95% CI, 2.42 to 17.25). CONCLUSIONS: In this prospective study, obesity raised the risks of total stroke mortality and hemorrhagic stroke mortality among Korean menopausal women. It was more evident with women who experienced menopause at age <50. The obese group of ever smokers was at an increased risk of ischemic stroke mortality.

Smoking and risk of tuberculosis incidence, mortality, and recurrence in South Korean men and women.

The authors explored the association of cigarette smoking with tuberculosis incidence, recurrence, and mortality. A 14-year prospective cohort study (1992-2006) was carried out in 1,294,504 South Koreans. Participants were grouped by smoking history, and the authors assessed tuberculosis incidence, mortality, and recurrence risk for each group. Unadjusted and adjusted Cox proportional hazards models were used to investigate the association between smoking history and the 3 outcomes of interest, adjusting for age and alcohol use. Compared with never smokers, current smokers had increased mortality from tuberculosis among both men (adjusted hazard ratio (HR) = 1.6, 95% confidence interval (CI): 1.3, 2.0) and women (HR = 1.6, 95% CI: 1.0, 2.4). Current male smokers had greater risk of incident tuberculosis than former smokers (HR = 1.4, 95% CI: 1.3, 1.5), and risk among current smokers increased with number of cigarettes smoked daily. In females, cigarette smoking was not associated with incident tuberculosis. There was interaction between smoking and sex for incidence (P = 0.00047). The effect of smoking was generally reduced with adjustment for body mass index. Among men, the highest alcohol consumption category (> or =100 g/day) was associated with risk of incident tuberculosis (HR = 1.5, 95% CI: 1.3, 1.7). This study provides longitudinal evidence that smoking increases risk of incident tuberculosis, mortality from tuberculosis, and tuberculosis recurrence.

Body-mass index and mortality in Korean men and women.

BACKGROUND: Obesity is associated with diverse health risks, but the role of body weight as a risk factor for death remains controversial. METHODS: We examined the association between body weight and the risk of death in a 12-year prospective cohort study of 1,213,829 Koreans between the ages of 30 and 95 years. We examined 82,372 deaths from any cause and 48,731 deaths from specific diseases (including 29,123 from cancer, 16,426 from atherosclerotic cardiovascular disease, and 3362 from respiratory disease) in relation to the body-mass index (BMI) (the weight in kilograms divided by the square of the height in meters). RESULTS: In both sexes, the average baseline BMI was 23.2, and the rate of death from any cause had a J-shaped association with the BMI, regardless of cigarette-smoking history. The risk of death from any cause was lowest among patients with a BMI of 23.0 to 24.9. In all groups, the risk of death from respiratory causes was higher among subjects with a lower BMI, and the risk of death from atherosclerotic cardiovascular disease or cancer was higher among subjects with a higher BMI. The relative risk of death associated with BMI declined with increasing age. CONCLUSIONS: Underweight, overweight, and obese men and women had higher rates of death than men and women of normal weight. The association of BMI with death varied according to the cause of death and was modified by age, sex, and smoking history.

Body mass index and serum aminotransferase levels in Korean men and women.

BACKGROUND AND AIMS: Obesity has been postulated as contributing to the risk of nonalcoholic steatohepatitis. With the surging obesity epidemic, an ensuing epidemic of nonalcoholic steatohepatitis and its sequelae is of concern. The objectives of this clinical research study were to examine the association between body mass index (BMI) and serum aminotransferase levels. METHOD: A study was carried out on 1,166,847 Koreans (731,560 men and 435,287 women), 30 to 95 years of age, who received health insurance from the National Health Insurance Corp and had a biennial medical evaluation from 1992 to 1995. RESULTS: Across the range of BMI values (<18.5 to >or=32 kg/m) in men, alanine aminotransferase (ALT) was estimated to increase by 18.8 U/L and aspartate aminotransferase (AST) increased by 7.1 U/L. In women, ALT increased by 9.9 U/L, whereas AST increased by 4.5 U/L. In men, interactions between BMI and alcohol consumption were significant (P<0.001) for ALT and AST, but the degree of effect modification was quantitatively minor. However, ALT and AST levels were somewhat higher in heavy alcohol drinkers than in nondrinkers. For women, the relationship of aminotransferase levels with BMI did not vary by alcohol consumption. The relationship of BMI with aminotransferase weakened with increasing age. CONCLUSIONS: In Korea, ALT and AST are strongly associated with BMI and increased progressively from the lowest to the highest strata of BMI. The association of BMI with aminotransferase levels was modified by age and sex.

Total cholesterol and mortality from ischemic heart disease and overall cardiovascular disease in Korean adults.

It is not completely clear whether "the lower, the better" cholesterol hypothesis for cardiovascular disease (CVD) and ischemic heart disease (IHD) can be applied to general populations with a low risk of heart disease mortality.We prospectively followed up 503,340 Koreans who participated in routine health checkups during 2002-2003 until 2013 via linkage to national mortality records.Nonlinear associations with total cholesterol (TC) were found: U-curves for overall CVD (I00-I99; nadir at 180-200 mg/dL) and a reverse-L-curve for IHD (I20-I25). Assuming a linear association in the lower range (<200 mg/dL), TC was inversely associated with CVD mortality (HR per 39 mg/dL [1 mmol/L] increase = 0.90). In the upper range (200-349 mg/dL), TC was positively associated with CVD mortality, largely due to IHD (HR = 1.19), especially acute myocardial infarction (HR = 1.23). The associations were generally similar in men versus women and in middle-aged (40-64 years) versus elderly (≥65 years) adults.TC levels of 180-200 mg/dL were associated with the lowest CVD mortality. Below 200 mg/dL, TC had no graded positive associations with IHD mortality. It remains unclear whether the lowest cholesterol levels are associated with the least mortality from CVD and IHD in Korean adults with a low risk of heart disease.