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.

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.

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.

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.

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.

Total cholesterol and all-cause mortality by sex and age: a prospective cohort study among 12.8 million adults.

It is unclear whether associations between total cholesterol (TC) levels and all-cause mortality and the optimal TC ranges for lowest mortality vary by sex and age. 12,815,006 Korean adults underwent routine health examinations during 2001-2004, and were followed until 2013. During follow-up, 694,423 individuals died. U-curve associations were found. In the TC ranges of 50-199 and 200-449 mg/dL, each 39 mg/dL (1 mmol/L) increase in TC was associated with 23% lower (95% CI:23%,24%) and 7% higher (6%,7%) mortality, respectively. In the age groups of 18-34, 35-44, 45-54, 55-64, 65-74, and 75-99 years, each 1 mmol/L higher TC increased mortality by 14%, 13%, 8%, 7%, 6%, and 3%, respectively (P < 0.001 for each age group), for TC ≥ 200 mg/dL, while the corresponding TC changes decreased mortality by 13%, 27%, 34%, 31%, 20%, and 13%, respectively, in the range < 200 mg/dL (P < 0.001 for each age group). TC had U-curve associations with mortality in each age-sex group. TC levels associated with lowest mortality were 210-249 mg/dL, except for men aged 18-34 years (180-219 mg/dL) and women aged 18-34 years (160-199 mg/dL) and 35-44 years (180-219 mg/dL). The inverse associations for TC < 200 mg/dL were stronger than the positive associations in the upper range.

Total cholesterol and stroke mortality in middle-aged and elderly adults: A prospective cohort study.

BACKGROUND AND AIMS: The association between cholesterol and stroke has been inconsistent. This study aimed to examine the association between total cholesterol (TC) and mortality from total stroke and stroke subtypes. METHODS: 503,340 Korean adults aged 40-80 years without a history of heart disease or stroke participated in routine health examinations in 2002 and 2003, and were followed up until 2013. Adjusted hazard ratios (HRs) for stroke (I60-I69) mortality were calculated. RESULTS: Nonlinear associations for total stroke (U-curve) and hemorrhagic stroke (L-curve), especially intracerebral hemorrhage (ICH), but a linear association for ischemic stroke, were found. In the range <200 mg/dL, TC was inversely associated with stroke mortality (HR per 39 mg/dL [1 mmol/L] increase = 0.88 [95% CI = 0.80-0.95]), mainly due to hemorrhagic stroke (HR = 0.78 [0.68-0.90]), especially ICH (HR = 0.72 [0.62-0.85]). In the upper range (200-349 mg/dL), TC was positively associated with stroke mortality (HR = 1.09 [1.01-1.16]); ICH and subarachnoid hemorrhage mortality showed no inverse association. The associations were generally similar in middle-aged (40-64 years) and elderly (≥65 years) adults and, in the upper range, each 1 mmol/L (39 mg/dL) higher TC was associated with 11% higher mortality from stroke (95% CI = 2%-21%) in the elderly. Both middle-aged (39%) and elderly (23%) adults had higher ischemic stroke mortality associated with TC ≥240 mg/dL, compare to <200 mg/dL. CONCLUSIONS: TC level around 200 mg/dL was associated with the lowest risk of overall stroke in the elderly and middle-aged adults. No stroke subtype including ICH, was inversely associated with TC in the range ≥200 mg/dL.

Association of resting heart rate and hypertension stages on all-cause and cardiovascular mortality among elderly Koreans: the Kangwha Cohort Study.

BACKGROUND: Elevated resting heart rate and hypertension independently increase the risk of mortality. However, their combined effect on mortality in stages of hypertension according to updated clinical guidelines among elderly population is unclear. METHODS: We followed a cohort of 6100 residents (2600 males and 3500 females) of Kangwha County, Korea, ranging from 55 to 99 year-olds as of March 1985, for all-cause and cardiovascular mortality for 20.8 years until December 31, 2005. Mortality data were collected through telephone calls and visits (to 1991), and were confirmed by death record matching with the National Statistical Office (1992-2005). Hazard ratios were calculated for all-cause and cardiovascular mortality by resting heart rate and hypertension defined by Eighth Joint National Committee criteria using the Cox proportional hazard model after controlling for confounding factors. RESULTS: The hazard ratios associated with resting heart rate > 80 beats/min were higher in hypertensive men compared with normotensives with heart rate of 61-79 beats/min, with hazard ratios values of 1.43 (95% CI: 1.00-1.92) on all-cause mortality for prehypertension, 3.01 (95% CI: 1.07-8.28) on cardiovascular mortality for prehypertension, and 8.34 (95% CI: 2.52-28.19) for stage 2 hypertension. Increased risk (HR: 3.54, 95% CI: 1.16-9.21) was observed among those with both a resting heart rate ≥ 80 beats/min and prehypertension on cardiovascular mortality in women. CONCLUSIONS: Individuals with coexisting elevated resting heart rate and hypertension, even in prehypertension, have a greater risk for all-cause and cardiovascular mortality compared to those with elevated resting heart rate or hypertension alone. These findings suggest that elevated resting heart rate should not be regarded as a less serious risk factor in elderly hypertensive patients.

Impact of alcohol consumption and body mass index on mortality from nonneoplastic liver diseases, upper aerodigestive tract cancers, and alcohol use disorders in Korean older middle-aged men: Prospective cohort study.

Alcohol use is a leading risk factor for the global disease burden including liver diseases. However, the combined effect of alcohol use and body mass index (BMI) on alcohol-related diseases has seldom been examined. We examined whether alcohol consumption and BMI could act together to increase mortality from nonneoplastic liver diseases, upper aero-digestive tract (UADT) cancers, and alcohol use disorders (AUD) in middle-aged Korean men.107,735 men (mean age, 58.8 years) participated in a postal survey in 2004 and were followed until 2010, by linkage to national death records. Hazard ratios (HRs) of cause-specific death were calculated after adjustment for confounders.Each 5-drink (approximately 45 g alcohol) higher weekly alcohol consumption was associated with increased mortality, by approximately 70% for nonneoplastic liver disease mortality (HR = 1.70, P < 0.001), approximately 60% for UADT cancer mortality (HR = 1.64, P < 0.001), and approximately 70% for AUD mortality (HR = 1.71, P < 0.001). Generally, BMI was inversely associated with these alcohol-related diseases (HR per each 5 kg/m higher BMI = 0.18-0.46, P < 0.001 for each cause), while, in participants with BMI ≥25 kg/m, each 5 kg/m higher BMI was also associated with an elevated mortality from nonneoplastic liver diseases of approximately 150% (HR = 2.52, P = 0.001). Men with BMI < 21 kg/m and weekly alcohol consumption ≥14 drinks showed markedly higher mortality from nonneoplastic liver diseases (HR = 5.7), alcoholic liver diseases (HR = 9.3), UADT cancers (HR = 10.5), and esophageal cancer (HR = 15.5), compared to men drinking less than 1 drink/wk with BMI ≥25 kg/m. The combined effect of low BMI and high weekly alcohol consumption was 2.25- to 3.29-fold greater than the additive effect of each factor for these alcohol-related diseases (P < 0.05 for each cause).Alcohol consumption and low BMI were related to deaths from nonneoplastic liver diseases, UADT cancers, and AUD, with evidence of a supra-additive combined effect of both factors. High BMI was also related to deaths from nonneoplastic liver diseases. Men with a low BMI (<23 kg/m) are suggested to be prone to the harmful effects of alcohol.

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.

Body Mass Index and Cancer Mortality Among Korean Older Middle-Aged Men: A Prospective Cohort Study.

The association of body mass index (BMI; kg/m) with overall and site-specific cancer mortality in Asians is not well understood. A total of 113,478 men from the Korean Veterans Health Study who returned a postal survey in 2004 were followed up until 2010. The adjusted hazard ratios (HRs) of cancer mortality were calculated using a Cox model. During 6.4 years of follow-up, 3478 men died from cancer. A reverse J-curve association with a nadir at 25.0 to 27.4 kg/m was observed. Below 25 kg/m, the HRs of death for each 5 kg/m decrease in BMI were 1.72 (95% confidence interval = 1.57-1.90) for overall cancer; 3.63 (2.57-5.12) for upper aerodigestive tract (UADT) cancers, including oral cavity and larynx [HR = 4.21 (2.18-8.12)] and esophagus [HR = 2.96 (1.82-4.81)] cancers; 1.52 (1.35-1.71) for non-UADT and non-lung cancers, including stomach [HR = 2.72 (2.13-3.48)] and large intestine [HR = 1.68 (1.20-2.36)] cancers; and 1.93 (1.59-2.34) for lung cancer. In the range of 25 to 47 kg/m, the HRs for each 5 kg/m increase in BMI were 1.27 (1.03-1.56) for overall cancer mortality and 1.57 (1.02-2.43) for lung cancer mortality. In individuals <25 kg/m, inverse associations with mortality from overall cancer and non-UADT and non-lung cancer were stronger in never-smokers than in current smokers. Both low and high BMI were strong predictors of mortality from overall and several site-specific cancers in Korean men. Further research is needed to evaluate whether interventions involving weight change (loss or gain) reduce the risk of cancer or improve the survival.

Usual alcohol consumption and suicide mortality among the Korean elderly in rural communities: Kangwha Cohort Study.

BACKGROUND: The evidence from prospective studies on whether greater usual alcohol consumption is associated with a higher risk of death by suicide in the general population is inconclusive. METHODS: 6163 participants (2635 men; 3528 women) in a 1985 survey among rural residents in Korea aged 55 years and above were followed until 2008. A Cox model was used to calculate HRs of suicide death after adjustment for demographic, socioeconomic and health-related confounders. RESULTS: 37 men and 24 women died by suicide. Elderly persons who consumed alcohol daily, 70 g alcohol (5 drinks) or more per drinking day, or 210 g alcohol (15 drinks) or more per week had higher suicide mortality (p<0.05), compared with non-drinkers. An increase of one drinking day per week (HR=1.17, 95% CI 1.05 to 1.31), 70 g (5 drinks) additional alcohol intake per drinking day (HR=1.38, 95% CI 1.13 to 1.70), and 140 g (10 drinks) additional alcohol intake per week was associated with a 17%, 38% and 12% higher risk of suicide death, respectively. Women had a higher relative risk of suicide death associated with alcohol consumption, compared with men. CONCLUSIONS: A greater frequency and amount of usual alcohol consumption was linearly associated with higher suicide death. Given the same amount of alcohol consumption, women might have a higher relative risk of suicide than men. Our findings support 'the lower the better' for alcohol intake, no protective effect of moderate alcohol consumption, and a sex-specific guideline (lower alcohol threshold for women) as actions to prevent suicide death.

Sex-age-specific association of body mass index with all-cause mortality among 12.8 million Korean adults: a prospective cohort study.

BACKGROUND: Despite differences in body shape and adiposity characteristics according to sex and age, a single range of healthy weight [body mass index (BMI, kg/m(2)) of 18.5-24.9) regardless of sex and age has been recommended. The aim of the study is to examine whether the association between BMI and all-cause mortality varies by sex and age, and, if relevant, to estimate sex-age-specific optimal BMIs associated with a minimal risk of death. METHODS: A total of 12,832,637 Korean adults aged 18-99 years who participated in health examinations during 2001-04 were followed up until 2013. Hazard ratios of death in sex-age groups were calculated using Cox regression models after adjustment for age, smoking status and known pre-existing illness. RESULTS: During follow-up, 456,175 men and 241,208 women died. Among men, the age-specific optimal BMI was 23.0-25.9 (kg/m(2)) at 18-34 years, 24.0-27.9 at 45-54 year, and 25.0-28.9 at 65-74 years. Among women, it was 15.5-24.9 at 18-34 years, 21.0-26.9 at 45-54 years and 24.0-28.9 at 65-74 years. Patterns of sex-age-specific association generally did not differ between never-smokers with no known illness and all participants. Progressively increased risks above and below sex-age-specific optimums were observed (reverse J-curve). Smoking had a limited impact on the observed associations. CONCLUSIONS: Women had a lower optimal BMI than men, especially at younger ages. The optimal BMI increased with age. Change in optimal BMI with age, however, was more profound in women than in men. Sex-age-specific optimums were generally higher than the current normal weight (BMI of 18.5-24.9), except in women below 50 years. Sex-age-specific guidelines related to body weight may be needed to guide people for better health.

Low systolic blood pressure and mortality from all causes and vascular diseases among older middle-aged men: Korean Veterans Health Study.

OBJECTIVES: Recently, low systolic blood pressure (SBP) was found to be associated with an increased risk of death from vascular diseases in a rural elderly population in Korea. However, evidence on the association between low SBP and vascular diseases is scarce. The aim of this study was to prospectively examine the association between low SBP and mortality from all causes and vascular diseases in older middle-aged Korean men. METHODS: From 2004 to 2010, 94 085 Korean Vietnam War veterans were followed-up for deaths. The adjusted hazard ratios (aHR) were calculated using the Cox proportional hazard model. A stratified analysis was conducted by age at enrollment. SBP was self-reported by a postal survey in 2004. RESULTS: Among the participants aged 60 and older, the lowest SBP (<90 mmHg) category had an elevated aHR for mortality from all causes (aHR, 1.9; 95% confidence interval [CI], 1.2 to 3.1) and vascular diseases (International Classification of Disease, 10th revision, I00-I99; aHR, 3.2; 95% CI, 1.2 to 8.4) compared to those with an SBP of 100 to 119 mmHg. Those with an SBP below 80 mmHg (aHR, 4.5; 95% CI, 1.1 to 18.8) and those with an SBP of 80 to 89 mmHg (aHR, 3.1; 95% CI, 0.9 to 10.2) also had an increased risk of vascular mortality, compared to those with an SBP of 90 to 119 mmHg. This association was sustained when excluding the first two years of follow-up or preexisting vascular diseases. In men younger than 60 years, the association of low SBP was weaker than that in those aged 60 years or older. CONCLUSIONS: Our findings suggest that low SBP (<90 mmHg) may increase vascular mortality in Korean men aged 60 years or older.

Body mass index and mortality among Korean elderly in rural communities: Kangwha Cohort Study.

BACKGROUND: The relationship between body mass index (BMI) and mortality may differ by ethnicity, but its exact nature remains unclear among Koreans. The study aim was to prospectively examine the association between BMI and mortality in Korean. METHODS: 6166 residents (2636 men; 3530 women) of rural communities (Kangwha County, Republic of Korea) aged 55 and above were followed up for deaths from 1985-2008. The multivariable-adjusted hazard ratios were calculated using the Cox proportional hazards model. RESULTS: During the 23.8 years of follow-up (an average of 12.5 years in men and 15.7 years in women), 2174 men and 2372 women died. Men with BMI of 21.0-27.4 and women with BMI of 20.0-27.4 had a minimal risk for all-cause mortality. A lower BMI as well as a higher BMI increased the hazard ratio of death. For example, multivariable-adjusted hazard ratios associated with BMI below 16, and with BMI of 27.5 and above, were 2.4 (95% CI = 1.6-3.5) and 1.5 (95% CI = 1.1-1.9) respectively, in men, compared to those with BMI of 23.0-24.9. This reverse J-curve association was maintained among never smokers, and among people with no known chronic diseases. Higher BMI increased vascular mortality, while lower BMI increased deaths from vascular diseases, cancers, and, especially, respiratory diseases. Except for cancers, these associations were generally weaker in women than in men. CONCLUSIONS: A reverse J-curve association between BMI and all-cause mortality may exist. BMI of 21-27.4 (rather than the range suggested by WHO of 18.5-23 for Asians) may be considered a normal range with acceptable risk in Koreans aged 55 and above, and may be used as cut points for interventions. More concern should be given to people with BMI above and below a BMI range with acceptable risk. Further studies are needed to determine ethnicity-specific associations.

Low systolic blood pressure and mortality from all-cause and vascular diseases among the rural elderly in Korea; Kangwha cohort study.

The association between low systolic blood pressure (SBP) and vascular diseases is unclear. The aim of this study was to prospectively examine the association between SBP, especially low SBP, and mortality from all causes and vascular diseases among the elderly in Korea. Six thousand two hundred ninety four residents in a rural community were followed-up for deaths from 1985 to 2008. The adjusted hazard ratios (aHR) and 95% confidence intervals were calculated by Cox proportional hazard model. A stratified analysis was conducted by age at enrollment. Among the elderly aged 65 and above, the lowest SBP (<100 mm Hg) group had an elevated aHR for mortality from vascular diseases (aHR = 2.1, 95% CI = 1.2-3.9) including stroke (aHR = 2.4, 95% CI = 0.9-6.3) and ischemic heart diseases (aHR = 5.1, 95% CI = 1.0-26.0) compared to those with SBP of 100-119 mm Hg, while higher SBP was associated with higher mortality. This J-curve association was generally maintained when analysis was restricted to those with fair or good self-rated health, or those with no known vascular diseases. In people below 65, increasing SBP nearly monotonically increased the mortality from all-cause and vascular diseases. Our results suggest that elderly persons with low SBP should be treated with caution, since low SBP may increase vascular mortality.

Association between all-cause mortality and insurance status transition among the elderly population in a rural area in Korea: Kangwha Cohort Study.

The study purpose was to examine the association between health insurance transition and all-cause mortality. 3206 residents in Korea who participated in two surveys in 1985 and 1994, were followed-up during 1994-2008. Adjusted hazard ratios (aHR) were calculated using Cox hazard model. Participants were divided into four groups by insurance transition (the "National Health Insurance (NHI)-NHI", "NHI-Medicaid", "Medicaid-NHI", and "Medicaid-Medicaid" groups), where NHI-Medicaid means participants covered by NHI in 1985 but by Medicaid in 1994. For men covered by NHI in 1985, the mortality risk in the NHI-Medicaid was higher (aHR=1.47) than in the NHI-NHI. For men and women, covered by Medicaid in 1985, aHR was non-significantly lower in the Medicaid-NHI than in the Medicaid-Medicaid. When four groups were analyzed together, men in the Medicaid-Medicaid (aHR=1.67) and NHI-Medicaid (aHR=1.46) groups had higher mortality risk than males in the NHI-NHI, whereas no significant difference was observed for females. In conclusion, transition from NHI to Medicaid increases mortality risk, and transition from Medicaid to NHI may mitigate risk, while remaining on Medicaid pose the greatest risk, especially for men. Therefore, policy makers should strengthen coverage for Medicaid. The weak effects of transition from NHI to Medicaid on mortality for women require validation.