Mechanical upcycling of single-use face mask waste into high-performance composites: An ecofriendly approach with cost-benefit analysis

The COVID-19 pandemic created an unprecedented demand for PPE, with single-use face masks emerging as a critical tool in containing virus transmission. However, the extensive use and improper disposal of these single-use face masks, predominantly composed of non-biodegradable plastics, has exacerbated environmental challenges. This research presents an innovative method for mechanically upcycling PPEs used in medical sectors i.e. single use face masks. The study investigates a facile approach for reclamation of infection-free and pure polypropylene (PP) plastic from discarded single use face masks (W-PP) and blends it with various vegetable oil percentages (5, 10 and 20 %), resulting in a versatile material suitable for various applications. Melt flow index, rheological behaviour, DSC and FTIR were employed to investigate the effect of vegetable oil/radical initiator through chemical grafting on W-PP properties. The results demonstrate significant enhancements in the tensile strength and modulus of W-PP when blended with vegetable oil and a radical initiator. There was a marked increase in tensile strength (33 %) and strain (55 %) compared to untreated W-PP, rendering W-PP both robust and flexible. Furthermore, we employed this upcycled W-PP in the fabrication of glass fibre-reinforced composites, resulting in notable enhancements in both tensile strength and impact resistance. The upcycled W-PP demonstrates excellent potential for various applications, such as sheet forming and 3D printing, where the non-brittleness of plastics plays a pivotal role in manufacturing high-quality products. The cost-benefit analysis of this approach underscores the potential of upcycling PPE waste as a sustainable solution to mitigate plastic pollution and conserve valuable resources. The applications of this upcycled material span a wide range of industries, including automotive composites, packaging, and 3D printing.

Association of PM2.5 mass and its components with ovarian reserve in a northern peninsular province, China: The critical exposure period and components

BACKGROUND

A possible role of PM2.5 components on ovarian reserve has not been adequately unexplored.

OBJECTIVE

To evaluate the association between PM2.5 components and women' ovarian reserve over critical exposure periods in northern China, where the level of air pollution is among the nation's highest.

METHODS

We included 15,102 women with serum anti-Müllerian hormone (AMH) measurements from the Center for Reproductive Medicine of Shandong University during 2015-2019. Concentrations of PM2.5 and its five major components (0.1° × 0.1°), including sulfate, nitrate, ammonium, organic matter, and black carbon, were assigned to each residential address. Multivariable linear mixed effect models combined with constituent-residual models were performed to estimate the effect sizes of essential components over six short- to long-term exposure periods.

RESULTS

The strength of association was stronger during the process from primary to small antral follicle compared with other longer windows. For every interquartile range increase in PM2.5 mass was associated with - 8.7% (95%CI: -12.3%, -4.9%) change in AMH and the effect size was greatest for sulfate. Women with the lower level of attained education and those living inland were more susceptible compared with other population subgroups.

CONCLUSION

Exposure to specific components of air pollution during critical exposure windows is associated with a decline in ovarian reserve. These data add to the growing body of evidence that environmental factors have adverse effects on reproductive health, particularly for vulnerable population subgroups.

Climate change, environmental extremes, and human health in Australia: challenges, adaptation strategies, and policy gaps

Climate change presents a major public health concern in Australia, marked by unprecedented wildfires, heatwaves, floods, droughts, and the spread of climate-sensitive infectious diseases. Despite these challenges, Australia's response to the climate crisis has been inadequate and subject to change by politics, public sentiment, and global developments. This study illustrates the spatiotemporal patterns of selected climate-related environmental extremes (heatwaves, wildfires, floods, and droughts) across Australia during the past two decades, and summarizes climate adaptation measures and actions that have been taken by the national, state/territory, and local governments. Our findings reveal significant impacts of climate-related environmental extremes on the health and well-being of Australians. While governments have implemented various adaptation strategies, these plans must be further developed to yield concrete actions. Moreover, Indigenous Australians should not be left out in these adaptation efforts. A collaborative, comprehensive approach involving all levels of government is urgently needed to prevent, mitigate, and adapt to the health impacts of climate change.

Burden of Hypertensive Heart Disease and High Systolic Blood Pressure in Australia from 1990 to 2019: Results From the Global Burden of Diseases Study

BACKGROUND

There is a dearth of comprehensive studies examining the burden and trends of hypertensive heart disease (HHD) and high systolic blood pressure (SBP) among the Australian population. We aimed to explore the burden of HHD and high SBP, and how they changed over time from 1990 to 2019 in Australia.

METHODS

We analysed data from the Global Burden of Disease study in Australia. We assessed the prevalence, mortality, disability-adjusted life-years (DALY), years lived with disability (YLD) and years of life lost (YLL) attributable to HHD and high SBP. Data were presented as point estimates with 95% uncertainty intervals (UI). We compared the burden of HHD and high SBP in Australia with World Bank defined high-income countries and six other comparator countries with similar sociodemographic characteristics and economies.

RESULTS

From 1990 to 2019, the burden of HHD and high SBP in Australia reduced. Age standardised prevalence rate of HHD was 119.3 cases per 100,000 people (95% UI 86.6-161.0) in 1990, compared to 80.1 cases (95% UI 57.4-108.1) in 2019. Deaths due to HDD were 3.4 cases per 100,000 population (95% UI 2.6-3.8) in 1990, compared to 2.5 (95% UI 1.9-3.0) in 2019. HHD contributed to 57.2 (95% UI 46.6-64.7) DALYs per 100,000 population in 1990 compared to 38.4 (95% UI 32.0-45.2) in 2019. Death rates per 100,000 population attributable to high SBP declined significantly over time for both sexes from 1990 (155.6 cases; 95% UI 131.2-177.0) to approximately one third in 2019 (53.8 cases; 95% UI 43.4-64.4). Compared to six other countries in 2019, the prevalence of HHD was highest in the USA (274.3%) and lowest in the UK (52.6%), with Australia displaying the third highest prevalence. Australia ranked second in term of lowest rates of deaths and third for lowest DALYs respectively due to high SBP. From 1990-2019, Australia ranked third best for reductions in deaths and DALYs due to HHD and first for reductions in deaths and DALYs due to high SBP.

CONCLUSION

Over the past three decades, the burden of HHD in Australia has reduced, but its prevalence remains relatively high. The contribution of high SBP to deaths, DALYs and YLLs also reduced over the three decades.

A protocol for analysing the effects on health and greenhouse gas emissions of implemented climate change mitigation actions

Background: It is crucial to understand the benefits to human health from decarbonisation to galvanise action among decision makers. Most of our existing evidence comes from modelling studies and little is known about the extent to which the health co-benefits of climate change mitigation actions are realised upon implementation. We aim to analyse evidence from mitigation actions that have been implemented across a range of sectors and scales, to identify those that can improve and sustain health, while accelerating progress towards a zero-carbon economy.

Objectives: To understand the implementation process of actions and the role of key actors; explain the contextual elements influencing these actions; summarise what effects, both positive and negative, planned and unplanned they may have on emissions of greenhouse gases and health; and to summarise environmental, social, or economic co-benefits.

Data: We will review evidence collected through partnership with existing data holders and an open call for evidence. We will also conduct a hand search of reference lists from systematic reviews and websites of organisations relevant to climate change mitigation.

Screening: Screening will be done by two reviewers according to a pre-defined inclusion and exclusion criteria.

Analysis: We will identify gaps where implementation or evaluation of implementation of mitigation actions is lacking. We will synthesise the findings to describe how actions were implemented and how they achieved results in different contexts, identifying potential barriers and facilitators to their design, implementation, and uptake. We will also synthesise their effect on health outcomes and other co-benefits. Quantitative synthesis will depend on the heterogeneity of outcomes and metrics.

Conclusions: Findings will be used to identify lessons that can be learned from successful and unsuccessful mitigation actions, to make inferences on replicability, scalability, and transferability and will contribute to the development of frameworks that can be used by policy makers.

A protocol for analysing the effects on health and greenhouse gas emissions of implemented climate change mitigation actions

Background: It is crucial to understand the benefits to human health from decarbonisation to galvanise action among decision makers. Most of our existing evidence comes from modelling studies and little is known about the extent to which the health co-benefits of climate change mitigation actions are realised upon implementation. We aim to analyse evidence from mitigation actions that have been implemented across a range of sectors and scales, to identify those that can improve and sustain health, while accelerating progress towards a zero-carbon economy. Objectives: To understand the implementation process of actions and the role of key actors; explain the contextual elements influencing these actions; summarise what effects, both positive and negative, planned and unplanned they may have on emissions of greenhouse gases and health; and to summarise environmental, social, or economic co-benefits. Data: We will review evidence collected through partnership with existing data holders and an open call for evidence. We will also conduct a hand search of reference lists from systematic reviews and websites of organisations relevant to climate change mitigation. Screening: Screening will be done by two reviewers according to a pre-defined inclusion and exclusion criteria. Analysis: We will identify gaps where implementation or evaluation of implementation of mitigation actions is lacking. We will synthesise the findings to describe how actions were implemented and how they achieved results in different contexts, identifying potential barriers and facilitators to their design, implementation, and uptake. We will also synthesise their effect on health outcomes and other co-benefits. Quantitative synthesis will depend on the heterogeneity of outcomes and metrics. Conclusions: Findings will be used to identify lessons that can be learned from successful and unsuccessful mitigation actions, to make inferences on replicability, scalability, and transferability and will contribute to the development of frameworks that can be used by policy makers.

Mental health of new undergraduate students before and after COVID-19 in China

The purpose of this study was to examine the changes in severity of anxiety and depression symptoms, stress and sleeping quality after three months of mass quarantine for COVID-19 among undergraduate fresh students compared to their pre-COVID-19 measures. We used participants from the Chinese Undergraduate Cohort (CUC), a national prospective longitudinal study to examine the changes in anxiety and depression symptoms severity, stress and sleep quality after being under mass quarantine for three months. Wilcoxon matched pair signed-rank test was used to compare the lifestyle indicators. Severity of anxiety, depression symptoms, stress and sleep quality were compared with Wilcoxon signed-rank test. We used generalized estimating equation (GEE) to further quantify the change in mental health indicators and sleep quality after the COVID-19 mass quarantine compared to baseline. This study found that there was no deterioration in mental health status among Chinese new undergraduate students in 2020 after COVID-19 mass quarantine compared with the baseline measures in 2019. There was an improvement in sleep quality and anxiety symptoms. After adjusting for age, sex, exercise habit, time spent on mobile gadgets, and time spent outdoors, year 2020 was significantly associated with severity of depression symptoms in males (OR:1.52. 95%CI:1.05-2.20, p-value = 0.027). Year 2020 was significantly associated with the improvement of sleeping quality in total (OR:0.45, 95%CI:0.38-0.52, p < 0.001) and in all the subgroups. This longitudinal study found no deterioration in mental health status among Chinese new undergraduate students after three months of mass quarantine for COVID-19.

Sex disparities in the assessment and outcomes of chest pain presentations in emergency departments

OBJECTIVE

To determine whether sex differences exist in the triage, management and outcomes associated with non-traumatic chest pain presentations in the emergency department (ED).

METHODS

All adults (≥18 years) with non-traumatic chest pain presentations to three EDs in Melbourne, Australia between 2009 and 2013 were retrospectively analysed. Data sources included routinely collected hospital databases. Triage scoring of the urgency of presentation, time to medical examination, cardiac troponin testing, admission to specialised care units, and in-ED and in-hospital mortality were each modelled using the generalised estimating equations approach.

RESULTS

Overall 54 138 patients (48.7% women) presented with chest pain, contributing to 76 216 presentations, of which 26 282 (34.5%) were cardiac. In multivariable analyses, compared with men, women were 18% less likely to be allocated an urgency of 'immediate review' or 'within 10 min review' (OR=0.82, 95% CI 0.79 to 0.85), 16% less likely to be examined within the first hour of arrival to the ED by an emergency physician (0.84, 0.81 to 0.87), 20% less likely to have a troponin test performed (0.80, 0.77 to 0.83), 36% less likely to be admitted to a specialised care unit (0.64, 0.61 to 0.68), and 35% (p=0.039) and 36% (p=0.002) more likely to die in the ED and in the hospital, respectively.

CONCLUSIONS

In the ED, systemic sex bias, to the detriment of women, exists in the early management and treatment of non-traumatic chest pain. Future studies that identify the drivers explaining why women presenting with chest pain are disadvantaged in terms of care, relative to men, are warranted.

Modeling the Present and Future Incidence of Pediatric Hand, Foot, and Mouth Disease Associated with Ambient Temperature in Mainland China

BACKGROUND

There is limited evidence about the association between ambient temperature and the incidence of pediatric hand, foot, and mouth disease (HFMD) nationwide in China.

OBJECTIVES

We examined the childhood temperature-HFMD associations across mainland China, and we projected the change in HFMD cases due to projected temperature change by the 2090s.

METHODS

Data on daily HFMD (children 0-14 y old) counts and weather were collected from 362 sites during 2009-2014. Daily temperature by the 2090s was downscaled under the Representative Concentration Pathway (RCP) 4.5 and 8.5 scenarios. Temperature-HFMD associations were quantified using a two-stage Poisson regression with a distributed lag nonlinear model. The impact of changes in temperature on the incidence of HFMD was estimated by combining the fitted temperature-HFMD associations with projected temperatures under each scenario, assuming a constant population structure. Sensitivity analyses were performed to assess the influence of primary model assumptions.

RESULTS

During 2009-2014, >11 million HFMD cases were reported. In most regions, the temperature-HFMD association had an inverted U shape with a peak at approximately 20°C, but the association leveled off or continued to increase in the Inner Mongolia and Northeast regions. When estimates were pooled across all regions and the population size was held constant, the projected incidence of HFMD increased by 3.2% [95% empirical confidence interval (eCI): −13.5%, 20.0%] and 5.3% (95% eCI: −33.3%, 44.0%) by the 2090s under the RCP 4.5 and 8.5 scenarios, respectively. However, regional projections suggest that HFMD may decrease with climate change in temperate areas of central and eastern China.

CONCLUSION

Our estimates suggest that the association between temperature and HFMD varies across China and that the future impact of climate change on HFMD incidence will vary as well. Other factors, including changes in the size of the population at risk (children 0-14 y old) will also influence future HFMD trends. https://doi.org/10.1289/EHP3062.

Impact of ambient temperature on clinical visits for cardio-respiratory diseases in rural villages in northwest China

BACKGROUND

The association between temperature and cardio-respiratory disease in urban areas has been widely reported but there is limited information from populations living in rural areas that may be disproportionately affected by climate change.

OBJECTIVES

To quantify the associations between daily temperature and clinical visits due to cardiovascular and/or respiratory disease in rural villages in the Ningxia Hui Autonomous Region, China over 2012-2015.

METHODS

Daily data on clinical visits and weather conditions were collated from 203 villages. A quasi-Poisson regression with distributed lag non-linear model was used to examine the associations between daily temperature and clinical visits up to 28days, after controlling for potential confounders.

RESULTS

Over three years, 158,733 and 1,272,212 clinical visits were recorded for cardiovascular and respiratory diseases, respectively. Both low and high temperatures were associated with an increased risk of clinical visits for cardiovascular-related conditions, whereas only low temperatures were associated with increased clinical visits related to respiratory illness. The cold effect on cardiovascular visits appeared at the lag 6th day and persisted until the 22nd day, resulting in a cumulative relative risk (RR) 1.55 (95% CI: 1.26-1.92), compared with the minimum-clinical visit temperature. The cold effect on respiratory visits appeared immediately and lasted over the lag 0-28days, with a cumulative RR 2.96 (2.74-3.21). Suboptimal temperature accounted for approximately 13% and 26% of clinic visits due to cardiovascular and respiratory disorders, respectively, with the majority of cases attributable to moderate - rather than extreme - cold temperature.

CONCLUSIONS

In rural settings, sub-optimal temperatures explained nearly one quarter of all clinical visits due to cardiovascular and respiratory diseases. Although extreme cold temperature had a stronger, more immediate, prolonged effect on respiratory disease than for cardiovascular disease, moderately cold temperatures accounted for most of the overall burden of clinical visits.

Ambient temperature and emergency department visits: Time-series analysis in 12 Chinese cities

BACKGROUND

The association between ambient temperature and mortality has been well documented worldwide. However, limited data are available on nonfatal health outcomes, such as emergency department visits (EDVs), particularly from China.

OBJECTIVES

To examine the temperature-EDV association in 12 Chinese cities; and to assess the modification effects by region, gender and age.

METHODS

Daily meteorological data and non-accidental EDVs were collected during 2011-2014. Poisson regression with distributed lag non-linear model was applied to examine the temperature-lag-EDV association in each city. The effect estimates were pooled using multivariate meta-analysis at the national and regional level. Stratified analyses were performed by gender and age-groups. Sensitivity analyses adjusting for air pollution and relative humidity were conducted.

RESULTS

A total of 4,443,127 EDVs were collected from the 12 cities. Both cold and hot temperatures were associated with increased risk of EDVs, with minimum-mortality temperature located at 64th percentile of temperature. The effect of cold temperature appeared on day 2 and persisted until day 30, causing a cumulative relative risk (RR) of 1.80 (1.54, 2.11). The effect of hot temperature appeared immediately and lasted until day 3, with a cumulative RR of 1.15 (1.03, 1.29). The effect of temperature on EDVs was similar in male and female but was attenuated with increasing age. The effect of cold temperature on EDVs was greater in southern areas of the country whereas the hot effect was greater in northern cities. The association was robust to a large range of sensitivity analyses.

CONCLUSIONS

In China, there is a U-shaped association between temperature and risk of EDVs that is independent of air pollution and humidity. The temperature-EDV association varies with latitude and age-groups but is not affected by gender. Forecasting models for hospital emergency departments may be improved if temperature is included as an independent predictor.

The burden of lung cancer mortality attributable to fine particles in China

Although studies have examined the associations between fine particles (PM_2.5) and lung cancer mortality in US and European countries, the evidence is still limited for China. In addition, no study has provided estimates of spatial variation in lung cancer mortality attributable to PM_2.5 in China. In this study, we quantified the associations between lung cancer mortality and PM_2.5, using a spatiotemporal model with observed data of lung cancer mortality from 75 communities from the National Cancer Registration of China from 1990 to 2009 and the annual concentrations of PM_2.5 at 0.5°×0.5° spatial resolution. We also estimated lung cancer mortality burden attributable to PM_2.5 in China, with predicted county level lung cancer deaths in 2005. We found that the PM_2.5-lung cancer mortality associations were non-linear, with thresholds of 40μg/m³ overall, 45μg/m³ for male, 42μg/m³ for female, 45μg/m³ for those aged 30-64years, 48μg/m³ for those aged 65-74years, and 40μg/m³ for those aged 75years and more, above which the relative risks were 1.08 (95% CI: 1.07, 1.09), 1.07 (95% CI: 1.05, 1.08), 1.12 (95% CI: 1.1, 1.14), 1.05 (95% CI: 1.04, 1.07), 1.07 (95% CI: 1.06, 1.09), and 1.14 (95% CI: 1.12, 1.16) respectively. There were 51,219 (95% CI: 45,745-56,512) lung cancer deaths attributed to PM_2.5 in 2005, with attributable fractions of 13.7% (95% CI: 12.23-15.11%) overall, 10.01% (95% CI: 8.37-11.58%) for men, 18.06% (95% CI: 15.81-20.18%) for women, 8.35% (95% CI: 6.07-10.51%) for those aged 65-74years, 9.73% (95% CI: 7.6-11.75%) for those aged 65-74years, 21.7% (95% CI: 19.27-23.99%) for those aged 75years or more. In conclusion, assuming a causal relation a reduction in exposure levels of PM_2.5 below thresholds would avert a substantial number of deaths from lung cancer in China.

The association between ambient air pollution and selected adverse pregnancy outcomes in China: A systematic review

The association between exposure to ambient air pollution and respiratory or cardiovascular endpoints is well-established. An increasing number of studies have shown that this exposure is also associated with adverse pregnancy outcomes. However, the majority of research has been undertaken in high-income western countries, with relatively lower levels of exposure. There is now a sufficient number of studies to warrant an assessment of effects in China, a relatively higher exposure setting. We conducted a systematic review of 25 studies examining the association between ambient air pollution exposure and adverse pregnancy outcomes (lower birth weight, preterm birth, mortality, and congenital anomaly) in China, published between 1980 and 2015. The results indicated that sulphur dioxide (SO2) was more consistently associated with lower birth weight and preterm birth, and that coarse particulate matter (PM10) was associated with congenital anomaly, notably cardiovascular defects.

The impact of ambient fine particles on influenza transmission and the modification effects of temperature in China: A multi-city study

BACKGROUND

There is good evidence that air pollution is a risk factor for adverse respiratory and vascular health outcomes. However, data are limited as to whether ambient fine particles contribute to the transmission of influenza and if so, how the association is modified by weather conditions.

OBJECTIVES

We examined the relationship between ambient PM_2.5 and influenza incidence at the national level in China and explored the associations at different temperatures.

METHODS

Daily data on concentrations of particulate matter with aerodynamic diameter<2.5μm (PM_2.5) and influenza incidence counts were collected in 47 Chinese cities. A Poisson regression model was used to estimate the city-specific PM_2.5-influenza association, after controlling for potential confounders. Then, a random-effect meta-analysis was used to pool the effects at national level. In addition, stratified analyses were performed to examine modification effects of ambient temperature.

RESULTS

For single lag models, the highest effect of ambient PM_2.5 on influenza incidence appeared at lag day 2, with relative risk (RR) of 1.015 (95% confidence interval (CI): 1.004, 1.025) associated with a 10μg/m³ increase in PM_2.5. For moving average lag models, the significant association was found at lag 2-3days, with RR of 1.020 (95% CI: 1.006, 1.034). The RR of influenza transmission associated with PM_2.5 was higher for cold compared with hot days. Overall, 10.7% of incident influenza cases may result from exposure to ambient PM_2.5.

CONCLUSIONS

Ambient PM_2.5 may increase the risk of exposure to influenza in China especially on cooler days. Control measures to reduce PM_2.5 concentrations could potentially also be of benefit in lowering the risk of exposure and subsequent transmission of influenza in China.

Cumulative Exposure to Ideal Cardiovascular Health and Incident Diabetes in a Chinese Population: The Kailuan Study

Background

It is unclear whether ideal cardiovascular health (CVH), and particularly cumulative exposure to ideal CVH (cumCVH), is associated with incident diabetes. We aimed to fill this research gap.

Methods and Results

The Kailuan Study is a prospective cohort of 101 510 adults aged 18 to 98 years recruited in 2006–2007 and who were subsequently followed up at 2‐ (Exam 2), 4‐ (Exam 3), and 6 (Exam 4)‐year intervals after baseline. The main analysis is restricted to those individuals with complete follow‐up at all 4 examinations and who had no history of diabetes until Exam 3. Cumulative exposure to ideal CVH (cumCVH) was calculated as the summed CVH score for each examination multiplied by the time between the 2 examinations (score×year). Logistic regression models were used to assess the association between cumCVH and incident diabetes. In fully adjusted models, compared with the lowest quintile of cumCVH, individuals in the highest quintile had ~68% (95% confidence interval [CI] 60‐75) lower risk for incident diabetes (compared with 61% [95% CI 52‐69] lower risk when using baseline CVH). Every additional year lived with a 1‐unit increase in ideal CVH was associated with a 24% (95% CI 21‐28) reduction in incident diabetes.

Conclusions

Ideal CVH is associated with a reduced incidence of diabetes, but the association is likely to be underestimated if baseline measures of CVH exposure are used. Measures of cumulative exposure to ideal CVH are more likely to reflect lifetime risk of diabetes and possibly other health outcomes.

Clinical Trial Registration

URL: https://www.chictr.org. Unique identifier: ChiCTRTNC‐11001489.

Body-mass index and all-cause mortality: individual-participant-data meta-analysis of 239 prospective studies in four continents

BACKGROUND

Overweight and obesity are increasing worldwide. To help assess their relevance to mortality in different populations we conducted individual-participant data meta-analyses of prospective studies of body-mass index (BMI), limiting confounding and reverse causality by restricting analyses to never-smokers and excluding pre-existing disease and the first 5 years of follow-up.

METHODS

Of 10 625 411 participants in Asia, Australia and New Zealand, Europe, and North America from 239 prospective studies (median follow-up 13·7 years, IQR 11·4-14·7), 3 951 455 people in 189 studies were never-smokers without chronic diseases at recruitment who survived 5 years, of whom 385 879 died. The primary analyses are of these deaths, and study, age, and sex adjusted hazard ratios (HRs), relative to BMI 22·5-<25·0 kg/m(2).

FINDINGS

All-cause mortality was minimal at 20·0-25·0 kg/m(2) (HR 1·00, 95% CI 0·98-1·02 for BMI 20·0-<22·5 kg/m(2); 1·00, 0·99-1·01 for BMI 22·5-<25·0 kg/m(2)), and increased significantly both just below this range (1·13, 1·09-1·17 for BMI 18·5-<20·0 kg/m(2); 1·51, 1·43-1·59 for BMI 15·0-<18·5) and throughout the overweight range (1·07, 1·07-1·08 for BMI 25·0-<27·5 kg/m(2); 1·20, 1·18-1·22 for BMI 27·5-<30·0 kg/m(2)). The HR for obesity grade 1 (BMI 30·0-<35·0 kg/m(2)) was 1·45, 95% CI 1·41-1·48; the HR for obesity grade 2 (35·0-<40·0 kg/m(2)) was 1·94, 1·87-2·01; and the HR for obesity grade 3 (40·0-<60·0 kg/m(2)) was 2·76, 2·60-2·92. For BMI over 25·0 kg/m(2), mortality increased approximately log-linearly with BMI; the HR per 5 kg/m(2) units higher BMI was 1·39 (1·34-1·43) in Europe, 1·29 (1·26-1·32) in North America, 1·39 (1·34-1·44) in east Asia, and 1·31 (1·27-1·35) in Australia and New Zealand. This HR per 5 kg/m(2) units higher BMI (for BMI over 25 kg/m(2)) was greater in younger than older people (1·52, 95% CI 1·47-1·56, for BMI measured at 35-49 years vs 1·21, 1·17-1·25, for BMI measured at 70-89 years; pheterogeneity<0·0001), greater in men than women (1·51, 1·46-1·56, vs 1·30, 1·26-1·33; pheterogeneity<0·0001), but similar in studies with self-reported and measured BMI.

INTERPRETATION

The associations of both overweight and obesity with higher all-cause mortality were broadly consistent in four continents. This finding supports strategies to combat the entire spectrum of excess adiposity in many populations.

FUNDING

UK Medical Research Council, British Heart Foundation, National Institute for Health Research, US National Institutes of Health.

The harms of smoking and benefits of smoking cessation in women compared with men with type 2 diabetes: an observational analysis of the ADVANCE (Action in Diabetes and Vascular Disease: Preterax and Diamicron modified release Controlled Evaluation) trial

OBJECTIVES

In general populations, the adverse effects of smoking on coronary risk have been demonstrated to be greater in women than in men; whether this is true for individuals with diabetes is unclear.

DESIGN

Cohort study.

SETTING

20 countries worldwide participating in the ADVANCE (Action in Diabetes and Vascular Disease: Preterax and Diamicron modified release Controlled Evaluation) trial.

PARTICIPANTS

11,140 patients with type 2 diabetes aged ≥ 55 years and in cardiovascular risk at the time of randomisation.

PRIMARY AND SECONDARY OUTCOME MEASURES

Major cardiovascular events (death from cardiovascular disease, non-fatal stroke or non-fatal myocardial infarction (MI)), all cardiovascular events (major cardiovascular event or peripheral arterial disease or transient ischaemic attack), and all-cause mortality. Secondary outcome measures were major coronary events (fatal and non-fatal MI), major cerebrovascular events (fatal and non-fatal stroke), nephropathy (new or worsening renal disease), and all cancer.

RESULTS

At baseline, 6466 (56% women) participants were never-smokers, 1550 (28% women) were daily smokers and 3124 (21% women) were former smokers. Median follow-up time was 5 years. In Cox regression models after multiple adjustments, compared with never smoking, daily smoking was associated with increased risk of all primary and secondary outcomes with the exception of major cerebrovascular disease. Only for major coronary events was there any evidence of a stronger effect in women than in men (ratio of the adjusted HRs women:men; 1.64 (0.83 to 3.26) p=0.08). For all other outcomes considered, the hazards of smoking were similar in men and women. Quitting smoking was associated with a 30% reduction in all-cause mortality (p=0.001) in both sexes.

CONCLUSIONS

In individuals with diabetes, the effects of smoking on all major forms of cardiovascular disease are equally as hazardous in women and men with the possible exception of major coronary events where there was some evidence of a greater hazard in women.

TRIAL REGISTRATION NUMBER

NCT00145925.

The association between lung cancer incidence and ambient air pollution in China: A spatiotemporal analysis

BACKGROUND

China is experiencing more and more days of serious air pollution recently, and has the highest lung cancer burden in the world.

OBJECTIVES

To examine the associations between lung cancer incidence and fine particles (PM2.5) and ozone in China.

METHODS

We used 75 communities' data of lung cancer incidence from the National Cancer Registration of China from 1990 to 2009. The annual concentrations of fine particles (PM2.5) and ozone at 0.1°×0.1° spatial resolution were generated by combing remote sensing, global chemical transport models, and improvements in coverage of surface measurements. A spatial age-period-cohort model was used to examine the relative risks of lung cancer incidence associated with the air pollutants, after adjusting for impacts of age, period, and birth cohort, sex, and community type (rural and urban) as well as the spatial variation on lung cancer incidence.

RESULTS

The relative risks of lung cancer incidence related to a 10 µg/m(3) increase in 2-year average PM2.5 were 1.055 (95% confidence interval (CI): 1.038, 1.072) for men, 1.149 (1.120, 1.178) for women, 1.060 (1.044, 1.075) for an urban communities, 1.037 (0.998, 1.078) for a rural population, 1.074 (1.052, 1.096) for people aged 30-65 years, and 1.111 (1.077, 1.146) for those aged over 75 years. Ozone also had a significant association with lung cancer incidence.

CONCLUSIONS

The increased risks of lung cancer incidence were associated with PM2.5 and ozone air pollution. Control measures to reduce air pollution would likely lower the future incidence of lung cancer.

Comparison of anthropometric measures as predictors of cancer incidence: A pooled collaborative analysis of 11 Australian cohorts

Obesity is a risk factor for cancer. However, it is not known if general adiposity, as measured by body mass index (BMI) or central adiposity [e.g., waist circumference (WC)] have stronger associations with cancer, or which anthropometric measure best predicts cancer risk. We included 79,458 men and women from the Australian and New Zealand Diabetes and Cancer Collaboration with complete data on anthropometry [BMI, WC, Hip Circumference (HC), WHR, waist to height ratio (WtHR), A Body Shape Index (ABSI)], linked to the Australian Cancer Database. Cox proportional hazards models assessed the association between each anthropometric marker, per standard deviation and the risk of overall, colorectal, post-menopausal (PM) breast, prostate and obesity-related cancers. We assessed the discriminative ability of models using Harrell's c-statistic. All anthropometric markers were associated with overall, colorectal and obesity-related cancers. BMI, WC and HC were associated with PM breast cancer and no significant associations were seen for prostate cancer. Strongest associations were observed for WC across all outcomes, excluding PM breast cancer for which HC was strongest. WC had greater discrimination compared to BMI for overall and colorectal cancer in men and women with c-statistics ranging from 0.70 to 0.71. We show all anthropometric measures are associated with the overall, colorectal, PM breast and obesity-related cancer in men and women, but not prostate cancer. WC discriminated marginally better than BMI. However, all anthropometric measures were similarly moderately predictive of cancer risk. We do not recommend one anthropometric marker over another for assessing an individuals' risk of cancer.

Effects of blood pressure lowering on cardiovascular risk according to baseline body-mass index: a meta-analysis of randomised trials

BACKGROUND

The cardiovascular benefits of blood pressure lowering in obese people compared with people of normal weight might depend on choice of drug. We compared the effects of blood pressure-lowering regimens on cardiovascular risk in groups of patients categorised by baseline body-mass index (BMI).

METHODS

We used individual patient data from trials included in the Blood Pressure Lowering Treatment Trialists' Collaboration to compare the effects of different classes of blood pressure-lowering regimens for the primary outcome of total major cardiovascular events (stroke, coronary heart disease, heart failure, and cardiovascular death). We used meta-analyses and meta-regressions to assess interactions between treatment and BMI when fitted as either a categorical variable (<25 kg/m(2), 25 to <30 kg/m(2), and ≥30 kg/m(2)) or a continuous variable.

FINDINGS

Analyses were based on 135,715 individuals from 22 trials who had 14,353 major cardiovascular events. None of the six primary comparisons showed evidence that protection varied by drug class across the three BMI groups (all p for trend >0·20). When analysed as a continuous variable, angiotensin-converting-enzyme inhibitors gave slightly greater protection for each 5 kg/m(2) higher BMI than did calcium antagonists (hazard ratio 0·93, 95% CI 0·89-0·98; p=0·004) or diuretics (0·93, 0·89-0·98; p=0·002). The meta-regressions showed no relation between BMI category and the risk reduction for a given fall in systolic blood pressure. By contrast with a previous report, we noted no relation between BMI and the efficacy of calcium antagonists compared with diuretics.

INTERPRETATION

We found little evidence that selection of a particular class of blood pressure-lowering drug will lead to substantially different outcomes for individuals who are obese compared with those who are lean.

FUNDING

None.

The Asia pacific cohort studies collaboration: a decade of achievements

The Asia Pacific Cohort Studies Collaboration (APCSC) was established in the late 1990s when there was a distinct shortfall in evidence of the importance of risk factors for cardiovascular disease in Asia. With few exceptions, most notably from Japan, most of the published reports on cardiovascular disease in the last century were from Western countries, and there was uncertainty how far etiological associations found in the West could be assumed to prevail in the East. Against this background, APCSC was set up as a pooling project, combining individual participant data (about 600,000 subjects) from all available leading cohort studies (36 from Asia and 8 from Australasia) in the region, to fill the knowledge gaps. In the past 10 years, APCSC has published 50 peer-reviewed publications of original epidemiological research, primarily concerned with coronary heart disease, stroke, and cancer. This work has established that Western risk factors generally act similarly in Asia and in Australasia, just as they do in other parts of the world. Consequently, strategies to reduce the prevalence of elevated blood pressure, obesity, and smoking are at least as important in Asia as elsewhere- and possibly more important when the vast size of Asia is considered. This article reviews the achievements of APCSC in the past decade, with an emphasis on coronary heart disease.

Age at menarche and risk of type 2 diabetes among African-American and white women in the Atherosclerosis Risk in Communities (ARIC) study

AIMS/HYPOTHESIS

We examined race differences in the association between age at menarche and type 2 diabetes before and after adjustment for adiposity.

METHODS

We analysed baseline and 9-year follow-up data from 8,491 women (n = 2,505 African-American, mean age 53.3 years; n = 5,986 white, mean age 54.0 years) in the Atherosclerosis Risk in Communities (ARIC) study. Stratifying by race, we used logistic regression to estimate the OR for prevalent diabetes at baseline, and Cox proportional hazard models to estimate the HR for incident diabetes over follow-up according to age at menarche category (8-11, 12, 13, 14 and 15-18 years).

RESULTS

Adjusting for age and centre, we found that early age at menarche (8-11 vs 13 years) was associated with diabetes for white, but not African-American women in both the prevalent (white OR 1.72, 95% CI 1.32, 2.25; African-American OR 1.13, 95% CI 0.84, 1.51; interaction p = 0.043) and incident models (white HR 1.43, 95% CI 1.08, 1.89; African-American HR 1.20, 95% CI 0.87, 1.67; interaction p = 0.527). Adjustment for adiposity and lifestyle confounders attenuated associations for prevalent (white OR 1.41, 95% CI 1.05, 1.89; African-American OR 0.94, 95% CI 0.68, 1.30; interaction p = 0.093) and incident diabetes (white HR 1.22, 95% CI 0.92, 1.63; African-American HR 1.11, 95% CI 0.80, 1.56; interaction p = 0.554).

CONCLUSIONS/INTERPRETATION

Early menarche was associated with type 2 diabetes in white women, and adulthood adiposity attenuated the relationship. We did not find a similar association in African-American women. Our findings suggest that there may be race/ethnic differences in the influence of developmental factors in the aetiology of type 2 diabetes, which merit further investigation.

The association between resting heart rate, cardiovascular disease and mortality: evidence from 112,680 men and women in 12 cohorts

BACKGROUND

Multiple studies have examined the relationship between heart rate and mortality; however, there are discrepancies in results. Our aim was to describe the relationship between resting heart rate (RHR) and both major cardiovascular (CV) outcomes, as well as all-cause mortality in the Asia-Pacific region.

DESIGN AND METHODS

Individual data from 112,680 subjects in 12 cohort studies were pooled and analysed using Cox models, stratified by study and sex, and adjusted for age and systolic blood pressure.

RESULTS

During a mean 7.4 years follow-up, 6086 deaths and 2726 fatal or nonfatal CV events were recorded. There was a continuous, increasing association between having a RHR above approximately 65 beats/min and the risk of both CV and all-cause mortality, yet there was no evidence of associations below this threshold. The hazard ratio (95% CI) comparing the extreme quarters of RHR (80+ v <65 beats/min) was 1.44 (1.29-1.60) for CV and 1.54 (1.43-1.66) for total mortality. These associations were not materially changed by adjustment for other risk factors and exclusion of the first 2 years of follow-up. Hazard ratios of a similar magnitude were found for ischemic and hemorrhagic stroke, but the hazard ratio for heart failure was higher (2.08, 95% CI 1.07-4.06) and for Coronary Heart Disease (CHD) was lower (1.11, 95% CI 0.93-1.31) than for stroke.

CONCLUSIONS

RHR of above 65 beats/min has a strong independent effect on premature mortality and stroke, but a lesser effect on CHD. Lifestyle and pharmaceutical regimens to reduce RHR may be beneficial for people with moderate to high levels of RHR.

Does Body Mass Index Impact on the Relationship Between Systolic Blood Pressure and Cardiovascular Disease?

Background and Purpose—

Elevated blood pressure and excess body mass index (BMI) are established risk factors for cardiovascular disease (CVD) but controversy exists as to whether, and how, they interact.

Methods—

The interactions between systolic blood pressure and BMI on coronary heart disease, ischemic and hemorrhagic stroke and CVD were examined using data from 419 448 participants (≥30 years) in the Asia-Pacific region. BMI was categorized into 5 groups, using standard criteria, and systolic blood pressure was analyzed both as a categorical and continuous variable. Cox proportional hazard models, stratified by sex and study, were used to estimate hazard ratios, adjusting for age and smoking and the interaction was assessed by likelihood ratio tests.

Results—

During 2.6 million person-years of follow-up, there were 10 877 CVD events. Risks of CVD and subtypes increased monotonically with increasing systolic blood pressure in all BMI subgroups. There was some evidence of a decreasing hazard ratio, per additional 10 mm Hg systolic blood pressure, with increasing BMI, but the differences, although significant, are unlikely to be of clinical relevance. The hazard ratio for CVD was 1.34 (95% CI, 1.32–1.36) overall with individual hazard ratios ranging between 1.28 and 1.36 across all BMI groups. For coronary heart disease, ischemic stroke, and hemorrhagic stroke, the overall hazard ratios per 10 mm Hg systolic blood pressure were 1.24, 1.46, and 1.65, respectively.

Conclusions—

Increased blood pressure is an important determinant of CVD risk irrespective of BMI. Although its effect tends to be weaker in people with relatively high BMI, the difference is not sufficiently great to warrant alterations to existing guidelines.

Oral disease in relation to future risk of dementia and cognitive decline: prospective cohort study based on the Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified-Release Controlled Evaluation (ADVANCE) trial

OBJECTIVE

Examine the association of oral disease with future dementia/cognitive decline in a cohort of people with type 2 diabetes.

METHODS

A total of 11,140 men and women aged 55-88 years at study induction with type 2 diabetes participated in a baseline medical examination when they reported the number of natural teeth and days of bleeding gums. Dementia and cognitive decline were ascertained periodically during a 5-year follow-up.

RESULTS

Relative to the group with the greatest number of teeth (more than or equal to 22), having no teeth was associated with the highest risk of both dementia (hazard ratio; 95% confidence interval: 1.48; 1.24, 1.78) and cognitive decline (1.39; 1.21, 1.59). Number of days of bleeding gums was unrelated to these outcomes.

CONCLUSIONS

Tooth loss was associated with an increased risk of both dementia and cognitive decline.

Total cholesterol and cancer risk in a large prospective study in Korea

PURPOSE

To further clarify the relationship between total cholesterol and cancer, which remains unclear.

METHODS

We prospectively examined the association between total cholesterol and site-specific and all-cancer incidence among 1,189,719 Korean adults enrolled in the National Health Insurance Corporation who underwent a standardized biennial medical examination in 1992 to 1995 and were observed for 14 years until cancer diagnosis or death.

RESULTS

Over follow-up, 53,944 men and 24,475 women were diagnosed with a primary cancer. Compared with levels less than 160 mg/dL, high total cholesterol (≥ 240 mg/dL) was positively associated with prostate cancer (hazard ratio [HR], 1.24; 95% CI, 1.07 to 1.44; P trend = .001) and colon cancer (HR, 1.12; 95% CI, 1.00 to 1.25; P trend = .05) in men and breast cancer in women (HR, 1.17; 95% CI, 1.03 to 1.33; P trend = .03). Higher total cholesterol was associated with a lower incidence of liver cancer (men: HR, 0.42; 95% CI, 0.38 to 0.45; P trend < .001; women: HR, 0.32; 95% CI, 0.27 to 0.39; P trend < .001), stomach cancer (men: HR, 0.87; 95% CI, 0.82 to 0.93; P trend ≤ .001; women: HR, 0.86; 95% CI, 0.77 to 0.97; P trend = .06), and, in men, lung cancer (HR, 0.89; 95% CI, 0.82 to 0.96; P trend < .001). Results for liver cancer were slightly attenuated after additional adjustment for liver enzyme levels and hepatitis B surface antigen status (men: HR, 0.60; P trend < .001; women: HR, 0.46; P trend = .003) and exclusion of the first 10 years of follow-up (men: HR, 0.59; P trend < .001; women: HR, 0.44; P trend < .001). Total cholesterol was inversely associated with all-cancer incidence in both men (HR, 0.84; 95% CI, 0.81 to 0.86; P trend < .001) and women (HR, 0.91; 95% CI, 0.87 to 0.95; P trend < .001), but these associations were attenuated after excluding incident liver cancers (men: HR, 0.95; P trend < .001; women: HR, 0.98; P trend = .32).

CONCLUSION

In this large prospective study, we found that total cholesterol was associated with the risk of several different cancers, although these relationships differed markedly by cancer site.

Erectile dysfunction and later cardiovascular disease in men with type 2 diabetes: prospective cohort study based on the ADVANCE (Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified-Release Controlled Evaluation) trial

OBJECTIVES

The aim of this study was to examine the relationship between erectile problems in men and cardiovascular disease (CVD) mortality.

BACKGROUND

Although there are plausible mechanisms linking erectile dysfunction (ED) with coronary heart disease (CHD) and stroke, studies are scarce.

METHODS

In a cohort analysis of the ADVANCE (Action in Diabetes and Vascular Disease: Preterax and Diamicron Modified-Release Controlled Evaluation) trial population, 6,304 men age 55 to 88 years with type 2 diabetes participated in a baseline medical examination when inquiries were made about ED. Over 5 years of follow-up, during which study members attended repeat clinical examinations, the presence of fatal and nonfatal CVD outcomes, cognitive decline, and dementia was ascertained.

RESULTS

After adjusting for a range of covariates, including existing illness, psychological health, and classic CVD risk factors, relative to those who were free of the condition, baseline ED was associated with an elevated risk of all CVD events (hazard ratio: 1.19; 95% confidence interval: 1.08 to 1.32), CHD (hazard ratio: 1.35; 95% confidence interval: 1.16 to 1.56), and cerebrovascular disease (hazard ratio: 1.36; 95% confidence interval: 1.11 to 1.67). Men who experienced ED at baseline and at 2-year follow-up had the highest risk for these outcomes.

CONCLUSIONS

In this cohort of men with type 2 diabetes, ED was associated with a range of CVD events.

Temporal trends in overweight and obesity of children and adolescents from nine Provinces in China from 1991-2006

OBJECTIVES

To assess temporal changes in mean body mass index (BMI) and the impact of socio-economic status on the prevalence of overweight and obesity among Chinese children and adolescents in nine provinces between 1991 and 2006.

METHODS

Analysis of height and weight data in children and adolescents aged 7-17 years with complete information on age, gender, region, height and weight from consecutive China Health and Nutrition Surveys (CHNS). Measurements were recorded in 1991, 1993, 1997, 2000, 2004 and 2006. Household income data in 2006 were included in the analysis of the impact of socio-economic status on the prevalence of overweight and obesity in children and adolescents. BMI cut-offs recommended by IOTF were used to define childhood overweight and obesity, as well as the Chinese cut-offs. The Cochrane-Mantel-Haenszel test for trend was used to examine the temporal trends in the prevalence of childhood overweight and obesity. Generalised estimating equations analysis was performed to assess the changes in BMI during the study period after adjusting for age, sex, region and income.

RESULTS

In Chinese children and adolescents mean BMI steadily increased from 17.4 kg/m(2) (95% CI: 17.3-17.5) in 1991 to 18.3 kg/m(2) (95% CI: 18.1-18.5) in 2006, after adjusting for age, sex, region and income level. There was a corresponding increase in the prevalence of overweight and obesity from 5.2% in 1991 to 13.2% in 2006. The greatest increase occurred among male children and adolescents in whom the prevalence of excess body weight tripled from 4.8% in 1991 to 15.4% in 2006, compared with 5.4% and 11.0% in females over the same period. In 2006, those from higher income families tended to have the highest prevalence of overweight and obesity.

CONCLUSIONS

The prevalence of overweight and obesity among Chinese children and adolescents has increased steadily over the past 15 years with the increase being apparent in all age, sex and income groups. However, the most noticeable increase was in children from urban areas and those from higher income backgrounds.

Influence of individual and combined health behaviors on total and cause-specific mortality in men and women: the United Kingdom health and lifestyle survey

BACKGROUND

Physical activity, diet, smoking, and alcohol consumption have been shown to be related to mortality. We examined prospectively the individual and combined influence of these risk factors on total and cause-specific mortality.

METHODS

The prospective cohort study included 4886 individuals at least 18 years old from a United Kingdom-wide population in 1984 to 1985. A health behavior score was calculated, allocating 1 point for each poor behavior: smoking; fruits and vegetables consumed less than 3 times daily; less than 2 hours physical activity per week; and weekly consumption of more than 14 units of alcohol (in women) and more than 21 units (in men) (range of points, 0-4). We examined the relationship between health behaviors and mortality using Cox models and compared it with the mortality risk associated with aging.

RESULTS

During a mean follow-up period of 20 years, 1080 participants died, 431 from cardiovascular diseases, 318 from cancer, and 331 from other causes. Adjusted hazard ratios and 95% confidence intervals (CIs) for total mortality associated with 1, 2, 3, and 4 poor health behaviors compared with those with none were 1.85 (95% CI, 1.28-2.68), 2.23 (95% CI, 1.55-3.20), 2.76 (95% CI, 1.91-3.99), and 3.49 (95% CI, 2.31-5.26), respectively (P value for trend, <.001). The effect of combined health behaviors was strongest for other deaths and weakest for cancer mortality. Those with 4 compared with those with no poor health behaviors had an all-cause mortality risk equivalent to being 12 years older.

CONCLUSION

The combined effect of poor health behaviors on mortality was substantial, indicating that modest, but sustained, improvements to diet and lifestyle could have significant public health benefits.

Impact of blood pressure lowering on cardiovascular outcomes in normal weight, overweight, and obese individuals: the Perindopril Protection Against Recurrent Stroke Study trial

There is considerable uncertainty regarding the efficacy of blood pressure-lowering therapy in reducing cardiovascular risk in obese people. In this report we examine the effects of blood pressure lowering according to baseline body mass index (kilograms per meter squared) in the Perindopril Protection Against Recurrent Stroke Study. A total of 6105 participants with cerebrovascular disease were randomized to perindopril-based blood pressure-lowering therapy or placebo. The overall mean difference in systolic/diastolic blood pressure between participants assigned active therapy or placebo was 9/4 mm Hg (SE: 0.5/0.3 mm Hg), with no difference by body mass index quarters (<23.1, 23.1 to 25.3, 25.4 to 27.8, and > or = 27.9 kg/m(2)). A consistent treatment benefit was demonstrated for protection against major vascular events across quarters with the following hazard ratios (95% CIs): 0.80 (0.62 to 1.02), 0.78 (0.61 to 1.01), 0.67 (0.53 to 0.86), 0.69 (0.54 to 0.88), and 0.74 (0.66 to 0.84; P for heterogeneity=0.16). Similar results were apparent for stroke and stroke subtypes (all P for heterogeneity > or = 0.07) or with the standard definitions of overweight and obesity (<25, 25 to 29, and > or = 30 kg/m(2); all P for heterogeneity > or = 0.28). The absolute effects of treatment were, however, more than twice that in the highest compared with the lowest body mass index quartile. Across increasing quarters of body mass index over 5 years, active therapy prevented 1 major vascular event among every 28, 23, 13, and 13 patients treated. In conclusion, blood pressure-lowering therapy produced comparable risk reductions in vascular disease across the whole range of body mass indices in participants with a history of stroke. However, the greater baseline level of cardiovascular risk in those with higher body mass index meant that these patients obtained the greatest benefit.

The discrimination of dyslipidaemia using anthropometric measures in ethnically diverse populations of the Asia-Pacific Region: the Obesity in Asia Collaboration

Dyslipidaemia is a major risk factor for cardiovascular disease and is only detectable through blood testing, which may not be feasible in resource-poor settings. As dyslipidaemia is commonly associated with excess weight, it may be possible to identify individuals with adverse lipid profiles using simple anthropometric measures. A total of 222 975 individuals from 18 studies were included as part of the Obesity in Asia Collaboration. Linear and logistic regression models were used to assess the association between measures of body size and dyslipidaemia. Body mass index, waist circumference, waist : hip ratio (WHR) and waist : height ratio were continuously associated with the lipid variables studied, but the relationships were consistently stronger for triglycerides and high-density lipoprotein cholesterol. The associations were similar between Asians and non-Asians, and no single anthropometric measure was superior at discriminating those individuals at increased risk of dyslipidaemia. WHR cut-points of 0.8 in women and 0.9 in men were applicable across both Asians and non-Asians for the discrimination of individuals with any form of dyslipidaemia. Measurement of central obesity may help to identify those individuals at increased risk of dyslipidaemia. WHR cut-points of 0.8 for women and 0.9 for men are optimal for discriminating those individuals likely to have adverse lipid profiles and in need of further clinical assessment.

Coffee, decaffeinated coffee, and tea consumption in relation to incident type 2 diabetes mellitus: a systematic review with meta-analysis

BACKGROUND

Coffee consumption has been reported to be inversely associated with risk of type 2 diabetes mellitus. Similar associations have also been reported for decaffeinated coffee and tea. We report herein the findings of meta-analyses for the association between coffee, decaffeinated coffee, and tea consumption with risk of diabetes.

METHODS

Relevant studies were identified through search engines using a combined text word and MeSH (Medical Subject Headings) search strategy. Prospective studies that reported an estimate of the association between coffee, decaffeinated coffee, or tea with incident diabetes between 1966 and July 2009.

RESULTS

Data from 18 studies with information on 457 922 participants reported on the association between coffee consumption and diabetes. Six (N = 225 516) and 7 studies (N = 286 701) also reported estimates of the association between decaffeinated coffee and tea with diabetes, respectively. We found an inverse log-linear relationship between coffee consumption and subsequent risk of diabetes such that every additional cup of coffee consumed in a day was associated with a 7% reduction in the excess risk of diabetes relative risk, 0.93 [95% confidence interval, 0.91-0.95]) after adjustment for potential confounders.

CONCLUSIONS

Owing to the presence of small-study bias, our results may represent an overestimate of the true magnitude of the association. Similar significant and inverse associations were observed with decaffeinated coffee and tea and risk of incident diabetes. High intakes of coffee, decaffeinated coffee, and tea are associated with reduced risk of diabetes. The putative protective effects of these beverages warrant further investigation in randomized trials.

Burden of lung cancer deaths due to smoking for men and women in the WHO Western Pacific and South East Asian regions

INTRODUCTION

Eighty percent of all smokers live in low and middle-income countries of the Asia Pacific region but actual estimates of the burden of disease due to smoking in the region have yet to be quantified.

METHODS

The burden of lung cancer due to smoking for all countries in the WHO Western Pacific and South East Asian regions was calculated from the population attributable fractions (PAFs). Nationally representative sex-specific prevalences of smoking were obtained from the World Health Organization, MEDLINE and/or national government documents and hazard ratios (HR) for lung cancer due to smoking in Asian and non-Asian populations were obtained from published data. The HR and prevalence were then used to calculate PAFs for lung cancer deaths due to smoking, by gender and by country.

RESULTS

The national prevalence of smoking in the Asia Pacific region ranged from 18-65% in men and from 0-50% in women. The fraction of lung cancer deaths attributable to smoking ranged from 0-40% in Asian women and from 21-49% in Asian men. In ANZ, PAFs were as high as 80% for women and 68% for men. Future estimates of the burden of smoking-related lung cancer in Asia were obtained by assuming a continuation of current smoking habits in these populations. By extrapolating the higher HR from the ANZ region to Asia, resulted in an increase in the PAFs to 4-90% in women and from 62-85% in men.

CONCLUSION

The current burden of lung-cancer due to smoking in the Asia-Pacific region is substantial accounting for up to 50% of deaths from the disease in men and up to 40% in women depending on the country. If current smoking habits in Asia remain unchanged then the number of people dying from smoking-related lung cancer over the next couple of decades is expected to double. It is known that the majority of lung cancer is due to smoking. This is the first paper to systematically compare current burdens of lung cancer deaths due to smoking in countries in the Western Pacific and South East Asia and by gender. Findings from this paper demonstrate the number of lung cancer deaths that could be prevented if the prevalence of smoking was eliminated.

Obesity and liver cancer mortality in Asia: The Asia Pacific Cohort Studies Collaboration

While obesity is associated with liver cancer in studies from western societies, the paucity of data from Asia limits insights into its aetiological role in this population. We examined the relationship between body mass index (BMI) and liver cancer mortality using data from the Asia Pacific Cohort Studies Collaboration. In 309,203 Asian study members, 4 years of follow-up gave rise to 11,135 deaths from all causes, 420 of which were ascribed to liver cancer. BMI, whether categorised according to current guidelines for Asian groups or World Health Organisation recommendations, was not associated with liver cancer in any of our analyses.

Systematic review: sodium bicarbonate treatment regimens for the prevention of contrast-induced nephropathy

BACKGROUND

Intravenous sodium bicarbonate has been proposed to reduce the risk for contrast-induced nephropathy (CIN).

PURPOSE

To determine the effect of sodium bicarbonate on the risk for CIN.

DATA SOURCES

MEDLINE, PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials from 1950 to December 2008; conference proceedings; and ClinicalTrials.gov, without language restriction.

STUDY SELECTION

Randomized, controlled trials of intravenous sodium bicarbonate that prespecified the outcome of CIN as a 25% increase in baseline serum creatinine level or an absolute increase of 44 micromol/L (0.5 mg/dL) after radiocontrast administration.

DATA EXTRACTION

Using standardized protocols, 2 reviewers serially abstracted data for each study.

DATA SYNTHESIS

23 published and unpublished trials with information on 3563 patients and 396 CIN events were included. The pooled relative risk was 0.62 (95% CI, 0.45 to 0.86), with evidence of significant heterogeneity across studies (I(2) = 49.1%; P = 0.004). Some heterogeneity was due to the difference in the estimates between published and unpublished studies: relative risk, 0.43 (CI, 0.25 to 0.75) versus 0.78 (CI, 0.52 to 1.17), respectively. Meta-regression showed that small, poor-quality studies that assessed outcomes soon after radiocontrast administration were more likely to suggest benefit (P < 0.05 for all). No clear effects of treatment on the risk for dialysis, heart failure, and total mortality were identified.

LIMITATION

Power to assess clinical end points was limited.

CONCLUSION

The effectiveness of sodium bicarbonate treatment to prevent CIN in high-risk patients remains uncertain. Earlier reports probably overestimated the magnitude of any benefit, whereas larger, more recent trials have had neutral results. Large multicenter trials are required to clarify whether sodium bicarbonate has value for prevention of CIN before routine use can be recommended.

PRIMARY FUNDING SOURCE

None.

Smoking, diabetes and cardiovascular diseases in men in the Asia Pacific region

BACKGROUND

To assess whether there is a statistical interaction between smoking and diabetes that is related to the risk of cardiovascular disease (CVD) in men in the Asia Pacific region.

METHODS

An individual participant data meta-analysis was conducted on 34 cohort studies, involving 16 492 participants with diabetes (47.4% smokers) and 188 897 without (47.6% smokers). Hazard ratios (HR) and 95% confidence intervals (CI) were calculated for smoking (stratified by study and adjusted for age) for those with and without diabetes.

RESULTS

In men with diabetes, the HR (95% CI) comparing current smokers with non-smokers was 1.42 (1.10-1.83) for coronary heart disease, 1.10 (0.88-1.37) for total stroke and 1.15 (0.98-1.35) for total CVD. The corresponding figures for men without diabetes were 1.47 (1.33-1.61), 1.27 (1.16-1.39) and 1.35 (1.27-1.44), respectively. There was no evidence of a statistical interaction between diabetes and current smoking, the number of cigarettes smoked per day or quitting smoking. Smoking cessation was associated with a 19% reduction in CVD risk, irrespective of diabetes status.

CONCLUSIONS

The effects of cigarette smoking and smoking cessation are broadly similar in men with and without diabetes. In Asia, where there are high rates of smoking and a rapidly increasing prevalence of diabetes, strategies that encourage smokers to quit are likely to have huge benefits in terms of reducing the burden of CVD in men with diabetes.

Body mass index, waist circumference and waist:hip ratio as predictors of cardiovascular risk--a review of the literature

Overweight and obesity have become a major public health problem in both developing and developed countries as they are causally related to a wide spectrum of chronic diseases including type II diabetes, cardiovascular diseases and cancer. However, uncertainty regarding the most appropriate means by which to define excess body weight remains. Traditionally, body mass index (BMI) has been the most widely used method by which to determine the prevalence of overweight in, and across, populations as well as an individual's level of risk. However, in recent years, measures of central obesity, principally waist circumference and the waist:hip ratio and to a lesser extent the waist:height ratio, which more accurately describe the distribution of body fat compared with BMI, have been suggested to be more closely associated with subsequent morbidity and mortality. There is also uncertainty about how these measures perform across diverse ethnic groups; earlier, most of the evidence regarding the relationships between excess weight and risk has been derived chiefly from Caucasian populations, and hence, it remains unclear whether the relationships are consistent in non-Caucasian populations. The purpose of this review, therefore, is to provide an overview of the current evidence-base focusing predominantly on three main questions: (1) Which, if any, of the commonly used anthropometric measures to define excess weight is more strongly associated with cardiovascular risk? (2) Which of the anthropometric measures is a better discriminator of risk? and (3) Are there any notable differences in the strength and nature of these associations across diverse ethnic groups?