Population Attributable Fraction of Mortality Associated with Tobacco Smoking in Japan: A Pooled Analysis of Three Large-scale Cohort Studies

Background

Quantitative measures of the burden of tobacco smoking in Asian countries are limited. We estimated the population attributable fraction (PAF) of mortality associated with smoking in Japan, using pooled data from three large-scale cohort studies.

Methods

In total, 296,836 participants (140,026 males and 156,810 females) aged 40-79 years underwent baseline surveys during the 1980s and early 1990s. The average follow-up period was 9.6 years. PAFs for all-cause mortality and individual tobacco-related diseases were estimated from smoking prevalence and relative risks.

Results

The prevalence of current and former smokers was 54.4% and 25.1% for males, and 8.1% and 2.4% for females. The PAF of all-cause mortality was 27.8% [95% confidence interval (CI): 25.2-30.4] for males and 6.7% (95% CI: 5.9-7.5) for females. The PAF of all-cause mortality calculated by summing the disease-specific PAFs was 19.1% (95% CI: 16.0-22.2) for males and 3.6% (95% CI: 3.0-4.2) for females. The estimated number of deaths attributable to smoking in Japan in 2005 was 163,000 for males and 33,000 for females based on the former set of PAFs, and 112,000 for males and 19,000 for females based on the latter set. The leading causes of smoking-attributable deaths were cancer (61% for males and 31% for females), ischemic heart diseases and stroke (23% for males and 51% for females), and chronic obstructive pulmonary diseases and pneumonia (11% for males and 13% for females).

Conclusion

The health burden due to smoking remains heavy among Japanese males. Considering the high prevalence of male current smokers and increasing prevalence of young female current smokers, effective tobacco controls and quantitative assessments of the health burden of smoking need to be continuously implemented in Japan.Key words: Cohort Studies, Population, Risk, Smoking     

Smoking and risk of all-cause mortality: the Jichi Medical School (JMS) Cohort Study

BACKGROUND: There have been comparatively few large-scale cohort studies analyzing all-cause mortality due to cigarette smoking. The goal of this analysis is to investigate the relationship between smoking status and all-cause mortality, and to evaluate the effect of smoking in the Japanese. METHODS: The baseline data were collected between 1992 and 1995. Ultimately, 10,873 Japanese (4,280 males and 6,593 females) aged 19 years or older from 12 rural communities located across Japan participated in the study. This analysis is based on the results, including the information on those who died and moved out of the communities, obtained by December 31, 2001. The Cox's proportional hazards model was used to calculate the hazard ratio (HR) of mortality for smoking with adjustment for age, systolic blood pressure, total cholesterol, body mass index, alcohol drinking habit and education. RESULTS: The mean follow-up period was 8.2 years, during which time, 284 males and 192 females died. The multivariate-adjusted HRs for total mortality among former and current smokers compared with never smokers were 1.09 (95% confidence interval [CI]: 0.73-1.61) and 1.65 (95% CI: 1.16-2.35) in males, and 0.98 (95% CI: 0.40-2.42) and 0.91 (95% CI: 0.42-1.95) in females, respectively. Those for the consumption of 1-14, 15-24, and 25+ cigarettes per day among male smokers were 1.62, 1.57, and 1.89, respectively. In females, there was no great difference in all-cause mortality between smokers and never smokers. CONCLUSIONS: The results of our study confirm an increased risk in males of premature death from all causes among Japanese with a smoking habit.     

代谢综合征对血液透析患者的心血管病死亡和全因死亡的影响

[目的]观察代谢综合征对血液透析患者心血管死亡和全因死亡的影响。[方法]收集了某院血透中心维持性血液透析患者共157例,观察36～42个月。对患者临床和实验室基本资料进行收集,记录死亡时间和原因。并对患者的体成分和营养状况进行评估。[结果]根据IDF代谢综合征定义,患者被分为代谢综合征(MS)组和无代谢综合征(non-MS)组。两组患者的心血管死亡和全因死亡差异无统计学意义(P﹥0.05)。MS组患者营养状况好于non-MS组(SGA评分,卡方检验,P=000)。白蛋白﹤37g/l和年龄﹥66岁是导致患者全因死亡率增加的独立危险因素(COX回归分析)。[结论]IDF代谢综合征未增加患者的心血管死亡和全因死亡风险,白蛋白水平下降和老年是导致患者全因死亡率增加的独立危险因素。     

11省市队列人群代谢综合征的流行病学研究

目的　探讨队列人群代谢综合征的流行病学特征。方法　在 1992年对 11省市队列人群 (35～ 6 4岁 ) 2 7739人进行基线危险因素的调查。计算队列人群代谢综合征患者各种因素的均值±标准差和标化患病率。结果　 (1) 11省市队列人群有代谢综合征者高腰围的百分率最高 ,男性为89 0 % ,女性为 85 1%。其他主要指标 (除高密度脂蛋白 )男性均高于女性 ;(2 )代谢综合征患病率为13 3% ,其中男性为 12 7% ,女性为 14 2 % ,且随年龄的增加而增长 ;(3)多元logistic分析结果表明 ,腰围和糖尿病家族史是男性代谢综合征患者的危险因素 ,女性为腰围和高血压家族史。高密度脂蛋白增高是代谢综合征的保护因素。结论　 11省市队列人群代谢综合征患病率较高 ,腰围增大是代谢综合征重要的危险因素。     

Age and the burden of death attributable to diabetes in the United States

Diabetes is a well-established cause of cardiovascular disease (CVD) and all-cause mortality. The burden of death attributable to diabetes in the United States is not well quantified, particularly with regard to age. The authors analyzed data from the Second National Health and Nutrition Examination Survey (NHANES II) (1976-1980) and the NHANES II Mortality Study, in which a nationally representative cohort of 9,250 adults aged 30-75 years was followed for 12-16 years, to determine all-cause and cause-specific mortality. Overall, between 1976 and 1980, the prevalence of diagnosed diabetes was 4.3%. By 1992, the relative hazard of all-cause mortality was 1.9 (95% confidence interval: 1.5, 2.3), and the population attributable risk (PAR) was 3.6%. The relative hazard of CVD mortality was 2.3 (95% confidence interval: 1.8, 2.8), and the PAR was 5.2%. Including participants with undiagnosed diabetes in the estimates increased the PAR for all-cause mortality to 5.1% and that for CVD mortality to 6.8%. Women had a higher prevalence of diagnosed diabetes than men and a greater relative hazard of death than nondiabetic women, leading to a higher PAR for women (3.8% for all causes and 7.3% for CVD) versus men (3.3% for all causes and 3.8% for CVD). These data suggest that diabetes accounts for at least 3.6% of all deaths and 5.2% of CVD deaths in US adults. Improvements in diabetes prevention and treatment should produce noticeable effects on US life expectancy.     

Mortality attributable to cigarette smoking in a cohort study in Japan

We conducted this study to estimate the association and population attributable risk (PAR) of smoking with all-cause and cause-specific mortality based on a general prospective cohort study in Japan. A total of 8,129 subjects (3,996 males and 4,133 females) aged 40 or over were analyzed. The follow-up period was from 1986 to 2003. Smoking habit was classified into three categories of never smoker, former smoker, and current smoker. The Cox proportional hazard model was used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI). We also estimated the PAR of smoking, and calculated the 95% CI of PAR based on the bootstrap procedure. A total of 112,151 person-years were counted for 8,129 subjects over an average of 13.7 years of follow-up. The results showed that smoking increased the risk of dying from all cancers, cardiovascular, and respiratory diseases in both sexes. For all causes of death, smokers had a HR of 1.30 (95% CI: 1.09, 1.54), PAR of 13.1% (95% CI: 7.6, 22.3) in males, and HR of 1.81 (95% CI: 1.43, 2.29), and PAR of 6.1% (95% CI: 3.1, 9.3) in females compared to never smokers. These results confirm an increased risk of mortality from all causes, as well as from all cancers, cardiovascular disease, and respiratory disease in relation to smoking habit. Smoking is responsible for a considerable proportion of deaths due to all causes as well as cause-specific deaths. Population-based antismoking programs should be implemented to reduce such avoidable deaths.     

Cardiovascular disease mortality and serum carotenoid levels: a Japanese population-based follow-up study

BACKGROUND: Some observational epidemiologic studies suggest that dietary and serum carotenoids are associated with reduced cardiovascular disease mortality. METHODS: Three thousand and sixty-one subjects (1,190 males and 1,871 females), aged 39 to 80 years, were recruited from residents of Hokkaido, Japan who had attended comprehensive health check-up programs from 1988 through 1995. Serum levels of alpha-carotene, beta-carotene, and lycopene were separately determined by high-performance liquid chromatography. Serum levels of total carotene consisted of the sum of alpha-carotene, beta-carotene, and lycopene levels. Each serum level of alpha-carotene, beta-carotene, lycopene, total carotene, triglyceride, and alanine transaminase (ALT) activity was transformed logarithmically. The hazard ratios of serum alpha- and beta-carotenes, lycopene, and total carotene values were estimated by the Cox proportional hazard model after adjusting for sex, age, and other potential confounding factors. RESULTS: During the 11.9-year follow-up period, 80 deaths (49 males and 31 females) from cardiovascular disease, 40 deaths from heart disease, and 37 deaths from stroke were identified among the cohort subjects. High serum values of carotenoids such as alpha- and beta-carotenes, and lycopene were found to be significantly associated with low hazard ratios for cardiovascular disease mortality. However, a significant inverse association between high serum lycopene value and the risk for stroke mortality was not always observed. CONCLUSIONS: High serum levels of total carotene, comprising alpha- and beta-carotenes and lycopene, may reduce the risk for cardiovascular disease mortality among the Japanese population.     

Association of serum uric acid with all-cause and cardiovascular disease mortality and incident myocardial infarction in the MONICA Augsburg cohort. World Health Organization Monitoring Trends and Determinants in Cardiovascular Diseases.

Because previous findings have been inconsistent, we explored the association of serum concentrations of uric acid with all-cause and cardiovascular disease mortality and myocardial infarction prospectively. We used data from 1,044 men who are members of the World Health Organization Monitoring Trends and Determinants in Cardiovascular Diseases (MONICA) Augsburg cohort. The men, 45-64 years of age in 1984-1985, were followed through 1992. There were 90 deaths, 44 of which were related to cardiovascular disease; 60 men developed incident nonfatal or fatal myocardial infarction. We estimated hazard rate ratios from Cox proportional hazard models. Uric acid levels > or =373 micromol/liter (fourth quartile) vs < or =319 micromol/liter (first and second quartile) independently predicted all-cause mortality [hazard rate ratio = 2.8; 95% confidence interval (CI) = 1.6-5.0] after adjustment for alcohol, total cholesterol/high-density lipoprotein cholesterol ratio, hypertension, use of diuretic drugs, smoking, body mass index, and education. The adjusted risk of cardiovascular disease mortality was 2.2 (95% CI = 1.0-4.8), and that of myocardial infarction was 1.7 (95% CI = 0.8-3.3). Although residual confounding cannot be excluded, our results are among the few, in men, demonstrating a strong positive association of elevated serum uric acid with all-cause mortality. Future investigations may be able to evaluate whether uric acid contributes independently to the development of cardiovascular disease or is simply a component of the atherogenic metabolic condition known as the insulin resistance syndrome.     

A combination of serum low albumin and above-average cholesterol level was associated with excess mortality

BACKGROUND: There is no population-based prospective study concerning the relation between serum albumin and mortality in a non-Western population, and few previous studies included the subgroup analysis stratified by serum cholesterol level. METHODS: A 13.7-year cohort study was conducted on 6,957 males and females aged 30-59 years from 300 randomly selected areas throughout Japan, who participated in the National Survey on Circulatory Disorders in 1980. RESULTS: In the group with median and above of total cholesterol, one standard deviation (SD) increment of serum albumin (2.6 g/L for males and 2.4 g/L for females) was inversely associated with all-cause mortality for both males and females (relative risk RR = 0.68 and 0.81: 95% confidence interval CI = 0.53-0.87 and 0.68-0.98), and with cancer mortality for females (RR = 0.74; 95% Cl = 0.57-0.96);and the lowest category of serum albumin (< or = 43 g/L) showed the highest cardiovascular mortality for males (RR = 5.04; 95% CI = 1.04-24.5) among the three albumin categories. These relationships were not evident in the group with total cholesterol level below median. CONCLUSION: A combination of a low albumin level and above average cholesterol level, even both within the clinical normal range,is associated with excess mortality in the Japanese general population.     

Betel nut chewing is associated with increased risk of cardiovascular disease and all-cause mortality in Taiwanese men

BACKGROUND: Betel nut chewing is related to several kinds of cancer, metabolic syndrome, and type 2 diabetes. Whether it is associated with a greater risk of cardiovascular disease (CVD) and all-cause mortality, however, remains unclear. OBJECTIVE: We aimed to investigate the association between betel nut chewing and CVD and all-cause mortality. DESIGN: A baseline cohort of 56,116 male participants > or = 20 y old were recruited from 4 nationwide health screening centers in Taiwan in 1998 and 1999. Cox proportional hazards regression analyses were used to estimate the relative risks (RRs) of CVD and all-cause mortality for betel nut chewers during an 8-y follow-up period. RESULTS: There were 1549 deaths during the follow-up period, 309 of which were due to CVD. After adjustment for age, body mass index, diabetes, hypertension, lipids, smoking, alcohol consumption, physical activity, income, and education level, the RRs (95% CI) of CVD and all-cause mortality among the former betel nut chewers were 1.56 (1.02, 2.38) and 1.40 (1.17, 1.68), respectively, and those among current chewers were 2.02 (1.31, 3.13) and 1.40 (1.16, 1.70), respectively, compared with persons who had never chewed betel quid. Current and former betel nut chewers had a higher risk of CVD mortality (RR: 2.10; P < 0.05) than did current and former smokers. Greater frequency of betel nut chewing was associated with greater CVD and all-cause mortality. CONCLUSIONS: Betel nut chewing was independently associated with a greater risk of CVD and all-cause mortality in Taiwanese men. Regular screening for betel nut chewing history may help prevent excess deaths in the future. An anti-betel nut chewing program is urgently warranted for current chewers.     

Obesity and all-cause mortality among black adults and white adults

In recent pooled analyses among whites and Asians, mortality was shown to rise markedly with increasing body mass index (BMI; weight (kg)/height (m)(2)), but much less is known about this association among blacks. This study prospectively examined all-cause mortality in relation to BMI among 22,014 black males, 9,343 white males, 30,810 black females, and 14,447 white females, aged 40-79 years, from the Southern Community Cohort Study, an epidemiologic cohort of largely low-income participants in 12 southeastern US states. Participants enrolled in the cohort from 2002 to 2009 and were followed up to 8.9 years. Hazard ratios and 95% confidence intervals for mortality were obtained from sex- and race-stratified Cox proportional hazards models in association with BMI at cohort entry, adjusting for age, education, income, cigarette smoking, and alcohol consumption. Elevated BMI was associated with increased mortality among whites (hazard ratios for BMI >40 vs. 20-24.9 = 1.37 (95% confidence interval (CI): 1.02, 1.84) and 1.47 (95% CI: 1.15, 1.89) for white males and white females, respectively) but not significantly among blacks (hazard ratios = 1.13 (95% CI: 0.89, 1.43) and 0.87 (95% CI: 0.72, 1.04) for black males and black females, respectively). In this large cohort, obesity in mid-to-late adulthood among blacks was not associated with the same excess mortality risk seen among whites.     

Sleep duration and mortality in Japan: the Jichi Medical School Cohort Study

BACKGROUND: Although sleep is one of the most important health-related factors, relationship between sleep duration and mortality has not been fully discussed. METHODS: Study subjects were 11,325 participants (4,419 males and 6,906 females) in the Jichi Medical School Cohort Study, a population-based prospective study. Baseline data were obtained by questionnaire and health checkups between April 1992 and July 1995 in 12 rural areas in Japan. Main outcome measures were all-cause and cause-specific mortality derived from death certificates up to December 31, 2001. Cox's proportional hazard models were applied to analyze the association of sleep duration with mortality. RESULTS: A total of 495 deaths (289 males and 206 females) were observed during the average of 8.2-year follow-up period. After adjusting for age, systolic blood pressure, serum total cholesterol, body mass index, smoking habits, alcohol drinking habits, education, and marital status, the hazard ratios (95% confidence intervals) of all-cause mortality for individuals sleeping shorter than 6 hours and 9 hours or longer were 2.4 (1.3-4.2) and 1.1 (0.8-1.6) in males, and 0.7 (0.2-2.3) and 1.5 (1.0-2.4) in females, respectively, relative to those with 7-7.9 hours sleep. CONCLUSION: Our data suggest that males with short sleep and females with long sleep were at an elevated risk of death.     

Age at menopause and mortality in Japan: the Jichi Medical School Cohort Study

BACKGROUND: Although several studies have reported increased mortality risk with early menopause, there were no studies examining the relationship between age at menopause and mortality in Japan. The goal of this analysis is to investigate the relationship between age at menopause and all-cause mortality among the Japanese. METHODS: Study subjects were 4,683 postmenopausal females in the Jichi Medical School Cohort Study, a population-based prospective study. Baseline data were obtained by questionnaire and health checkups between April 1992 and July 1995 in 12 rural areas in Japan. Main outcome measures were all-cause mortality derived from death certificates up to December 31, 2002. Cox's proportional hazard models were used to analyze the association of age at menopause with mortality. RESULTS: A total of 215 deaths were observed during the average of 9.2 year follow-up period. After adjusting for age, systolic blood pressure, serum total cholesterol level, serum high density lipoprotein cholesterol level, history of diabetes mellitus, body mass index, smoking habits, alcohol drinking habits, marital status, study area, and types of menopause, the hazard ratios (95% confidence intervals) of all-cause mortality were 2.10 (1.07-4.11), 0.68 (0.36-1.26), 0.94 (0.68-1.30), and 1.17 (0.63-2.20) for females with a menopause at ages younger than 40 years, 40-44, 50-54, and 55 or older, respectively, relative to those with menopause at age 45-49 years. CONCLUSIONS: Our data suggest that menopause aged younger than 40 years increases the risk of death from all causes among the Japanese.     

Zinc, copper, and magnesium and risks for all-cause, cancer, and cardiovascular mortality

BACKGROUND: Experimental data suggest that zinc, copper, and magnesium are involved in carcinogenesis and atherogenesis. Few longitudinal studies have related these minerals to cancer or cardiovascular disease mortality in a population. METHODS: Data from the Paris Prospective Study 2, a cohort of 4035 men age 30-60 years at baseline, were used to assess the association between serum zinc, copper, and magnesium and all-cause, cancer, and cardiovascular disease mortality. Serum mineral values measured at baseline were divided into quartiles and classified into low (1st quartile, referent group), medium (2nd-3rd quartiles), and high (4th quartile) values. During 18-year follow up, 339 deaths occurred, 176 as a result of cancer and 56 of cardiovascular origin. Relative risks (RRs) for each element were inferred using Cox's proportional hazard model after controlling for various potential confounders. RESULTS: High copper values (4th quartile) were associated with a 50% increase in RRs for all-cause deaths (RR = 1.5; 95% confidence interval = 1.1-2.1), a 40% increase for cancer mortality (1.4; 0.9-2.2), and a 30% increase for cardiovascular mortality (1.3; 0.6-2.8) compared with low values (1st quartile). High magnesium values were negatively related to mortality with a 40% decrease in RR for all-cause (0.6; 0.4-0.8) and cardiovascular deaths (0.6; 0.2-1.2) and by 50% for cancer deaths (0.5; 0.3-0.8). Additionally, subjects with a combination of low zinc and high copper values had synergistically increased all-cause (2.6; 1.4-5.0) and cancer (2.7; 1.0-7.3) mortality risks. Similarly, combined low zinc and high magnesium values were associated with decreased all-cause (0.2; 0.1-0.5) and cancer (0.2; 0.1-0.8) mortality risks. CONCLUSIONS: High serum copper, low serum magnesium, and concomitance of low serum zinc with high serum copper or low serum magnesium contribute to an increased mortality risk in middle-aged men.     

Vitamin/mineral supplementation and cancer, cardiovascular, and all-cause mortality in a German prospective cohort (EPIC-Heidelberg)

Purpose

To prospectively evaluate the association of vitamin/mineral supplementation with cancer, cardiovascular, and all-cause mortality.

Methods

In the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Heidelberg), which was recruited in 1994–1998, 23,943 participants without pre-existing cancer and myocardial infarction/stroke at baseline were included in the analyses. Vitamin/mineral supplementation was assessed at baseline and during follow-up. Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs).

Results

After an average follow-up time of 11?years, 1,101 deaths were documented (cancer deaths?=?513 and cardiovascular deaths?=?264). After adjustment for potential confounders, neither any vitamin/mineral supplementation nor multivitamin supplementation at baseline was statistically significantly associated with cancer, cardiovascular, or all-cause mortality. However, baseline users of antioxidant vitamin supplements had a significantly reduced risk of cancer mortality (HR: 0.52; 95% CI: 0.28, 0.97) and all-cause mortality (HR: 0.58; 95% CI: 0.38, 0.88). In comparison with never users, baseline non-users who started taking vitamin/mineral supplements during follow-up had significantly increased risks of cancer mortality (HR: 1.74; 95% CI: 1.09, 2.77) and all-cause mortality (HR: 1.58; 95% CI: 1.17, 2.14).

Conclusions

Based on limited numbers of users and cases, this cohort study suggests that supplementation of antioxidant vitamins might possibly reduce cancer and all-cause mortality. The significantly increased risks of cancer and all-cause mortality among baseline non-users who started taking supplements during follow-up may suggest a “sick-user effect,” which researchers should be cautious of in future observational studies.     

Plasma total homocysteine and cardiovascular and noncardiovascular mortality: the Hordaland Homocysteine Study.

BACKGROUND: Few population-based studies have assessed relations between plasma or serum total homocysteine (tHcy) and all-cause mortality. OBJECTIVE: Our goal was to study associations between plasma tHcy and all-cause, cardiovascular, and noncardiovascular mortality. DESIGN: This was a prospective cohort study of 2127 men and 2639 women aged 65-67 y in 1992-1993 when they were recruited as part of a population-based national cardiovascular screening program carried out in Hordaland County, Norway. RESULTS: During a median of 4.1 y of follow-up, 162 men and 97 women died. A strong relation was found between plasma tHcy and all-cause mortality. The association was highly significant for noncardiovascular and for cardiovascular causes of death. In a comparison of individuals having tHcy concentrations of 9.0-11.9, 12.0-14.9, 15.0-19.9, or > or = 20 micromol/L with individuals having a tHcy concentration < 9 micromol/L, adjusted mortality ratios were 1.4, 1.9, 2.3, and 3.6 (P for trend = 0.0002) for noncardiovascular and 1.3, 2.1, 2.6, and 3.5 (P for trend = 0.0002) for cardiovascular causes of death. A tHcy increment of 5 micromol/L was associated with a 49% (95% CI: 28%, 72%) increase in all-cause mortality, a 50% (95% CI: 21%, 85%) increase in cardiovascular mortality (121 deaths), a 26% (95% CI: -2%, 63%) increase in cancer mortality (103 deaths), and a 104% (95% CI: 44%, 289%) increase in noncancer, noncardiovascular mortality (33 deaths). CONCLUSION: Plasma tHcy is a strong predictor of both cardiovascular and noncardiovascular mortality in a general population of 65-72-y-olds. These results should encourage studies of tHcy in a wider perspective than one confined to cardiovascular disease.     

A mortality update of male and female capacitor workers exposed to polychlorinated biphenyls

This analysis represents a 5-year update of our mortality study of 7075 PCB exposed capacitor workers that now includes 1654 deaths and 235,984 person-years of observation with follow-up through 1998. In hourly males and females the observed number of deaths from all-cancers and all-causes were similar to the expected numbers. In salaried males all-cause and all-cancer mortality were significantly below the expected. In salaried females, all-cause mortality was significantly below the expected and all-cancer mortality was below the expected, but not significantly. We again failed to find any significant excess mortality in the a priori cancers of concern or in any other cancers in the total cohort or in the highly exposed portion of the cohort. These results expand on our previous observations and as before the data fail to demonstrate any causal association between occupational PCB exposure and excess cancer mortality or any other causes of death.     

Metabolic syndrome and all-cause mortality: a meta-analysis of prospective cohort studies

To synthesize the available data on the association between metabolic syndrome and all-cause mortality, we conducted a meta-analysis of prospective cohort studies. We performed a literature search using Medline, EMBASE and Cochrane Library from 2001 to December 2009, with no restrictions. We included studies if they were prospective, had an assessment of metabolic syndrome at baseline and risk of all-cause mortality. We recorded several characteristics for each study. We extracted relative risks (RR) and 95% confidence intervals (CI) and pooled them using fixed or random effects models. We performed sensitivity analysis, and assessed heterogeneity and publication bias. A total of 21 studies including 372,411 participants were included in our meta-analysis. 18,556 deaths from any cause occurred during a mean follow-up of 11.5 years. Individuals with the metabolic syndrome, compared to those without, had an increased mortality from all causes (pooled RR 1.46; 95% CI 1.35–1.57). The RR of all-cause mortality associated with metabolic syndrome was higher in studies using the National Cholesterol Education Program Adult Treatment Panel (NCEP) than the revised NCEP criteria (RR: 1.45 vs. 1.25; P = 0.0002). Metabolic syndrome is an important risk factor for all-cause mortality. The diagnosis and treatment of the underlying risk factors for the metabolic syndrome should be an important strategy for the reduction of all-cause mortality associated with metabolic syndrome in the general population.     

Assessing adult mortality in HIV-1-afflicted Zimbabwe (1998 -2003)

OBJECTIVE: To compare alternative methods to vital registration systems for estimating adult mortality, and describe patterns of mortality in Manicaland, Zimbabwe, which has been severely affected by HIV. METHODS: We compared estimates of adult mortality from (1) a single question on household mortality, (2) repeated household censuses, and (3) an adult cohort study with linked HIV testing from Manicaland, with a mathematical model fitted to local age-specific HIV prevalence (1998 -2000). FINDINGS: The crude death rate from the single question (29 per 1000 person-years) was roughly consistent with that from the mathematical model (22 -25 per 1000 person-years), but much higher than that from the household censuses (12 per 1000 person-years). Adult mortality in the household censuses (males 0.65; females 0.51) was lower than in the cohort study (males 0.77; females 0.57), while mathematical models gave a much higher estimate, especially for females (males 0.80 -0.83; females 0.75 -0.80). The population attributable fraction of adult deaths due to HIV was 0.61 for men and 0.70 for women, with life expectancy estimated to be 34.3 years for males and 38.2 years for females. CONCLUSION: Each method for estimating adult mortality had limitations in terms of loss to follow-up (cohort study), under-ascertainment (household censuses), transparency of underlying processes (single question), and sensitivity to parameterization (mathematical model). However, these analyses make clear the advantages of longitudinal cohort data, which provide more complete ascertainment than household censuses, highlight possible inaccuracies in model assumptions, and allow direct quantification of the impact of HIV.     

The association of resting heart rate and mortality by gender in a rural adult Chinese population: a cohort study with a 6-year follow-up

Aim

Although previous studies have reported an association between resting heart rate (RHR) and cancer mortality, the association is contradictory. The relationship between RHR and disease-specific mortality has not been explored in the Chinese population. We examined this relationship in a rural adult Chinese population from a cohort study with a 6-year follow-up.

Subjects and methods

The RHR of a cohort of 20,069 participants was measured between July–August of 2007 and July–August of 2008, and 17,151 participants (85.5 %) were followed up between July–August of 2013 and July –October of 2014. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95 % confidence intervals (95 % CIs) for deaths due to all causes, cardiovascular disease (CVD), stroke, cancer, and other causes in RHR groups.

Results

Males and females with RHR?≥?90 showed the highest all-cause mortality (33,27 and 1,226/100,000 person-years) and adjusted HR for all-cause deaths—2.20 (95 % CI 1.64–2.93) and 1.99 (1.43–2.77). A similar association was observed for deaths due to CVD, stroke and cancer (except for females), and other causes of mortality.

Conclusions

Elevated RHR may be an independent marker of all-cause, CVD and other causes of death for both sexes and stroke and cancer deaths for males.