Electronic Cigarette Usage Patterns and Perceptions in Adult Australians.

Despite their increasing popularity, and Australia's unique regulatory environment, how and why Australian adults use e-cigarettes and their perceptions of their safety, efficacy and regulation have not been extensively reported before. In this study, we screened 2217 adult Australians with the aim of assessing these questions in a sample of current or former e-cigarette users. A total of 505 out of 2217 respondents were current or former e-cigarette users, with only these respondents completing the full survey. Key findings of this survey included the high proportion of respondents who indicated they were currently using e-cigarettes (307 out of 2217 = 13.8%), and the high proportion of current e-cigarette users that were also smokers (74.6%). The majority of respondents used e-liquids containing nicotine (70.3%), despite it being illegal in Australia without a prescription, and the majority bought their devices and liquids in Australia (65.7%). Respondents reported using e-cigarettes in a variety of places, including inside the home, inside public places (where it is illegal to smoke tobacco cigarettes), and around other people-which has implications for second and third hand exposures. A significant proportion of current e-cigarette users (30.6%) thought that e-cigarettes were completely safe to use long-term, although in general, there was a large amount of uncertainty/ambivalence with respect to perceptions of e-cigarette safety and efficacy as smoking cessation tools. This study shows that e-cigarette use is common in Australia, and that appropriate dissemination of unbiased research findings on their safety and efficacy in smoking cessation is urgently required.

Relationship between obesity and lower rates of breast feeding initiation in regional Victoria, Australia: an 8-year retrospective panel study.

OBJECTIVES: Using routinely collected hospital data, this study explored secular trends over time in breast feeding initiation in a large Australian sample. The association between obesity and not breast feeding was investigated utilising a generalised estimating equations logistic regression that adjusted for sociodemographics, antenatal, intrapartum and postpartum conditions, mode of delivery and infant's-related covariates. DESIGN: Population-based retrospective panel. SETTING: A regional hospital that serves 26% of Victoria's 6.5 million population in Australia. PARTICIPANTS: All women experiencing live births between 2010 and 2017 were included. Women with missing body mass index (BMI) were excluded. RESULTS: A total of 7491 women contributed to 10 234 live births. At baseline, 57.2% of the women were overweight or obese, with obesity increasing over 8 years by 12.8%, p=0.001. Although, breast feeding increased over time, observed in all socioeconomic status (SES) and BMI categories, the lowest proportions were consistently found among the obese and morbidly obese (78.9% vs 87.1% in non-obese mothers, p<0.001). In the multivariable analysis, risk of not breast feeding was associated with higher BMI, teenage motherhood, smoking, belonging to the lowest SES class, gravidity >4 and undergoing an assisted vaginal or caesarean delivery. Compared with women with a normal weight, the obese and morbidly obese were 66% (OR 1.66, 95% CI 1.40 to 1.96, p<0.001) to 2.6 times (OR 2.61, 95% CI 2.07 to 3.29, p<0.001) less likely to breast feed, respectively. The detected dose-response effect between higher BMI and lower breast feeding was not explained by any of the study covariates. CONCLUSION: This study provides evidence of increasing breast feeding proportions in regional Victoria over the past decade. However, these proportions were lowest among the obese and morbidly obese and those coming from the most disadvantaged backgrounds suggesting the need for targeted interventions to support breast feeding among these groups. The psychosocial and physiological associations between obesity and breast feeding should further be investigated.

Trends in Hospital Admission Rates and Associated Direct Healthcare Costs in Brazil: A Nationwide Retrospective Study between 2000 and 2015.

BACKGROUND: In Brazil, the increase in non-fatal events presents a new, unprecedented challenge for the free and universally accessible public healthcare system (SUS), the size and nature of which has yet to be reliably quantified. We examined the change in all-cause and cause-specific SUS hospital admissions during 2000 to 2015. MATERIALS AND METHODS: Data on hospital admissions across 1,816 cities were collected from the Brazilian Unified Health System. The age-standardized rates of hospital admissions, the associated healthcare costs, and length of hospital stay were quantified. Stratum analyses were performed by age, sex, region, and cause-specific categories. RESULTS: Hospital admission rates decreased by 10.2‰ per decade to 54.2‰ in 2015. For admissions in 2015, healthcare costs per patient equaled US$353 (an increase of $23.5/year since 2000) with an average length of hospital stay of 5 days (a decline of 0.04 days/year since 2000). Circulatory diseases incurred the greatest financial costs. Children and the elderly were most susceptible, especially for pneumonia. Injury and poisoning were the primary reason for admission in adult males, whereas maternal and other female-specific conditions were the highest burden in females. The burden of hospital admission was highest in the south and lowest in the north and northeast. DISCUSSION: Although hospital admission rates and length of stay have decreased in Brazil since 2000, the decline has been offset by an increase in direct healthcare costs. Age-, sex-, and region-specific features of the disease burden should be factored into future plans for healthcare expenditure in Brazil.

Association of Cardiovascular Disease With Premature Mortality in the United States.

Importance: Cardiovascular disease (CVD) is a leading cause of morbidity and mortality in the United States. Despite substantial declines in CVD mortality rates during past decades, progress against cardiovascular deaths in midlife has stagnated, with rates increased in some US racial/ethnic groups. Objective: To examine the trends in premature (ages 25-64 years) mortality from CVD from 2000 to 2015 by demographics and county-level factors, including education, rurality, and the prevalence of smoking, obesity, and diabetes. Design, Setting, and Participants: This descriptive study used US national mortality data from the Surveillance, Epidemiology, and End Results data set and included all CVD deaths among individuals ages 25 to 64 years from January 2000 to December 2015. The data analysis began in February 2018. Exposures: Age, sex, race/ethnicity, and county-level factors. Main Outcomes and Measures: Age-standardized mortality rates and average annual percent change (AAPC) in rates by age, sex, race/ethnicity, and county-level factors (in quintiles) and relative risks of CVD mortality across quintiles of each county-level factor. Results: In 2000 to 2015, 2.3 million CVD deaths occurred among individuals age 25 to 64 years in the United States. There were significant declines in CVD mortality for black, Latinx, and Asian and Pacific Islander individuals (AAPC: range, -1.7 to -3.2%), although black people continued to have the highest CVD mortality rates. Mortality rates were second highest for American Indian/Alaskan Native individuals and increased significantly among those aged 25 to 49 years (AAPC: women, 2.1%; men, 1.3%). For white individuals, mortality rates plateaued among women age 25 to 49 years (AAPC, 0.05%). Declines in mortality rates were observed for most major CVD subtypes except for ischemic heart disease, which was stable in white women and increased in American Indian/Alaska Native women, hypertensive heart disease, for which significant increases in rates were observed in most racial/ethnic groups, and endocarditis, for which rates increased in white individuals and American Indian/Alaska Native men. Counties with the highest prevalence of diabetes (quintile 5 vs quintile 1: relative risk range 1.6-1.8 for white individuals and 1.4-1.6 for black individuals) had the most risk of CVD mortality. Conclusions and Relevance: There have been substantial declines in premature CVD mortality in much of the US population. However, increases in CVD mortality before age 50 years among American Indian/Alaska Native individuals, flattening rates in white people, and overall increases in deaths from hypertensive disease suggest that targeted public health interventions are needed to prevent these premature deaths.

Associations Between Sub-Clinical Markers of Cardiometabolic Risk and Exposure to Residential Indoor Air Pollutants in Healthy Adults in Perth, Western Australia: A Study Protocol.

BACKGROUND: A growing body of epidemiological and clinical evidence has implicated air pollution as an emerging risk factor for cardiometabolic disease. Whilst individuals spend up to two-thirds of daily time in their domestic residential environment, very few studies have been designed to objectively measure the sub-clinical markers of cardiometabolic risk with exposure to domestic indoor air pollutants. This cross-sectional study aims to investigate associations between the components of domestic indoor air quality and selected sub-clinical cardiometabolic risk factors in a cohort of healthy adults living in Perth, Western Australia. METHODS: One hundred and eleven non-smoking adults (65% female) living in non-smoking households who were aged between 35-69 years were recruited for the project. Study subjects were invited to participate in all sections of the study, which included: Domestic indoor air monitoring along with the concurrent 24 h ambulatory monitoring of peripheral and central blood pressure and measures of central hemodynamic indices, standardized questionnaires on aspects relating to current health status and the domestic environment, a 24 h time-activity diary during the monitoring period, and clinic-based health assessment involving collection of blood and urine biomarkers for lipid and glucose profiles, as well as measures of renal function and an analysis of central pulse wave and pulse wave velocity. RESULTS: This study provides a standardized approach to the study of sub-clinical cardiometabolic health effects that are related to the exposure to indoor air pollution. CONCLUSION: The findings of this study may provide direction for future research that will further contribute to our understanding of the relationship that exists between indoor air pollution and sub-clinical markers of cardiometabolic risk.

Smoking as a risk factor for lung cancer in women and men: a systematic review and meta-analysis.

OBJECTIVES: To investigate the sex-specific association between smoking and lung cancer. DESIGN: Systematic review and meta-analysis. DATA SOURCES: We searched PubMed and EMBASE from 1 January 1999 to 15 April 2016 for cohort studies. Cohort studies before 1 January 1999 were retrieved from a previous meta-analysis. Individual participant data from three sources were also available to supplement analyses of published literature. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Cohort studies reporting the sex-specific relative risk (RR) of lung cancer associated with smoking. RESULTS: Data from 29 studies representing 99 cohort studies, 7 million individuals and >50 000 incident lung cancer cases were included. The sex-specific RRs and their ratio comparing women with men were pooled using random-effects meta-analysis with inverse-variance weighting. The pooled multiple-adjusted lung cancer RR was 6.99 (95% Confidence Interval (CI) 5.09 to 9.59) in women and 7.33 (95% CI 4.90 to 10.96) in men. The pooled ratio of the RRs was 0.92 (95% CI 0.72 to 1.16; I2=89%; p<0.001), with no evidence of publication bias or differences across major pre-defined participant and study subtypes. The women-to-men ratio of RRs was 0.99 (95% CI 0.65 to 1.52), 1.11 (95% CI 0.75 to 1.64) and 0.94 (95% CI 0.69 to 1.30), for light, moderate and heavy smoking, respectively. CONCLUSIONS: Smoking yields similar risks of lung cancer in women compared with men. However, these data may underestimate the true risks of lung cancer among women, as the smoking epidemic has not yet reached full maturity in women. Continued efforts to measure the sex-specific association of smoking and lung cancer are required.

The Burden of Cardiovascular Disease Attributable to Major Modifiable Risk Factors in Indonesia.

BACKGROUND: In Indonesia, coronary heart disease (CHD) and stroke are estimated to cause more than 470 000 deaths annually. In order to inform primary prevention policies, we estimated the sex- and age-specific burden of CHD and stroke attributable to five major and modifiable vascular risk factors: cigarette smoking, hypertension, diabetes, elevated total cholesterol, and excess body weight. METHODS: Population attributable risks for CHD and stroke attributable to these risk factors individually were calculated using summary statistics obtained for prevalence of each risk factor specific to sex and to two age categories (<55 and ≥55 years) from a national survey in Indonesia. Age- and sex-specific relative risks for CHD and stroke associated with each of the five risk factors were derived from prospective data from the Asia-Pacific region. RESULTS: Hypertension was the leading vascular risk factor, explaining 20%-25% of all CHD and 36%-42% of all strokes in both sexes and approximately one-third of all CHD and half of all strokes across younger and older age groups alike. Smoking in men explained a substantial proportion of vascular events (25% of CHD and 17% of strokes). However, given that these risk factors are likely to be strongly correlated, these population attributable risk proportions are likely to be overestimates and require verification from future studies that are able to take into account correlation between risk factors. CONCLUSIONS: Implementation of effective population-based prevention strategies aimed at reducing levels of major cardiovascular risk factors, especially blood pressure, total cholesterol, and smoking prevalence among men, could reduce the growing burden of CVD in the Indonesian population.

Risk of Cardiovascular Disease from Cumulative Cigarette Use and the Impact of Smoking Intensity.

BACKGROUND: Relative risks (RRs) for cardiovascular disease (CVD) by smoking rate exhibit a concave pattern, with RRs in low rate smokers exceeding a linear extrapolation from higher rate smokers. However, cigarettes/day does not by itself fully characterize smoking-related risks. A reexamination of the concave pattern using a comprehensive representation of smoking may enhance insights. METHODS: Data were from the Atherosclerosis Risk in Communities (ARIC) Study, a prospective cohort enrolled in four areas of the US in 1987-1989. Follow-up was through 2008. Analyses included 14,233 participants, 245,915 person-years, and 3,411 CVD events. RESULTS: The concave RRs with cigarettes/day were consistent with cigarettes/day modifying a linear RR association of pack-years with CVD (i.e., strength of the pack-years association depended on cigarettes/day, indicating that the manner of pack-years accrual impacted risk). Smoking fewer cigarettes/day for longer duration was more deleterious than smoking more cigarettes/day for shorter duration (P < 0.01). For 50 pack-years (365,000 cigarettes), estimated RRs of CVD were 2.1 for accrual at 20 cigarettes/day and 1.6 for accrual at 50 cigarettes/day. Years since smoking cessation did not alter the diminishing strength of association with increasing cigarettes/day. Analyses that accounted for competing risks did not affect findings. CONCLUSION: Pack-years remained the primary determinant of smoking-related CVD risk; however, accrual influenced RRs. For equal pack-years, smoking fewer cigarettes/day for longer duration was more deleterious than smoking more cigarettes/day for shorter duration. This observation provides clues to better understanding the biological mechanisms, and reinforces the importance of cessation rather than smoking less to reduce CVD risk.

Age- and Sex-Specific Burden of Cardiovascular Disease Attributable to 5 Major and Modifiable Risk Factors in 10 Asian Countries of the Western Pacific Region.

Cardiovascular disease (CVD) is the leading cause of mortality worldwide, causing an estimated 18 million deaths annually. Much of the burden of CVD resides in lower- and middle-income countries, particularly those Asian countries comprising the Western Pacific Region. Epidemiological studies have convincingly shown that up to 90% of all CVD can be explained by a small number of modifiable risk factors, including blood pressure, smoking, diabetes, total cholesterol and excess body weight. However, the relationship between these risk factors and coronary artery disease and stroke often differ by age and sex, and yet these differences are often overlooked in burden of disease estimations. As such, that can result in either an over- or under-estimation of the disease burden in specific population subgroups, which may affect resource allocation of healthcare. In this review, we derive the most reliable and previously unpublished estimates of the age- and sex-specific burden of vascular disease attributable to the aforementioned risk factors for 10 of the most populous Asian countries in the Western Pacific Region. Understanding how the burden of vascular disease is distributed within and between populations is crucial for developing appropriate health policies and effective treatment strategies, particularly in resource-poor settings.

Socioeconomic status in relation to cardiovascular disease and cause-specific mortality: a comparison of Asian and Australasian populations in a pooled analysis.

OBJECTIVES: In Western countries, lower socioeconomic status is associated with a higher risk of cardiovascular disease (CVD) and premature mortality. These associations may plausibly differ in Asian populations, but data are scarce and direct comparisons between the two regions are lacking. We, thus, aimed to compare such associations between Asian and Western populations in a large collaborative study, using the highest level of education attained as our measure of social status. SETTING: Cohort studies in general populations conducted in Asia or Australasia. PARTICIPANTS: 303,036 people (71% from Asia) from 24 studies in the Asia Pacific Cohort Studies Collaboration. Studies had to have a prospective cohort study design, have accumulated at least 5000 person-years of follow-up, recorded date of birth (or age), sex and blood pressure at baseline and date of, or age at, death during follow-up. OUTCOME MEASURES: We used Cox regression models to estimate relationships between educational attainment and CVD (fatal or non-fatal), as well as all-cause, cardiovascular and cancer mortality. RESULTS: During more than two million person-years of follow-up, 11,065 deaths (3655 from CVD and 4313 from cancer) and 1809 CVD non-fatal events were recorded. Adjusting for classical CVD risk factors and alcohol drinking, hazard ratios (95% CIs) for primary relative to tertiary education in Asia (Australasia) were 1.81 (1.38, 2.36) (1.10 (0.99, 1.22)) for all-cause mortality, 2.47(1.47, 4.17) (1.24 (1.02, 1.51)) for CVD mortality, 1.66 (1.00, 2.78) (1.01 (0.87, 1.17)) for cancer mortality and 2.09 (1.34, 3.26) (1.23 (1.04, 1.46)) for all CVD. CONCLUSIONS: Lower educational attainment is associated with a higher risk of CVD or premature mortality in Asia, to a degree exceeding that in the Western populations of Australasia.

Risk of all-cause mortality and vascular events in women versus men with type 1 diabetes: a systematic review and meta-analysis.

BACKGROUND: Studies have suggested sex differences in the mortality rate associated with type 1 diabetes. We did a meta-analysis to provide reliable estimates of any sex differences in the effect of type 1 diabetes on risk of all-cause mortality and cause-specific outcomes. METHODS: We systematically searched PubMed for studies published between Jan 1, 1966, and Nov 26, 2014. Selected studies reported sex-specific estimates of the standardised mortality ratio (SMR) or hazard ratios associated with type 1 diabetes, either for all-cause mortality or cause-specific outcomes. We used random effects meta-analyses with inverse variance weighting to obtain sex-specific SMRs and their pooled ratio (women to men) for all-cause mortality, for mortality from cardiovascular disease, renal disease, cancer, the combined outcome of accident and suicide, and from incident coronary heart disease and stroke associated with type 1 diabetes. FINDINGS: Data from 26 studies including 214 114 individuals and 15 273 events were included. The pooled women-to-men ratio of the SMR for all-cause mortality was 1·37 (95% CI 1·21-1·56), for incident stroke 1·37 (1·03-1·81), for fatal renal disease 1·44 (1·02-2·05), and for fatal cardiovascular diseases 1·86 (1·62-2·15). For incident coronary heart disease the sex difference was more extreme; the pooled women-to-men ratio of the SMR was 2·54 (95% CI 1·80-3·60). No evidence suggested a sex difference for mortality associated with type 1 diabetes from cancer, or accident and suicide. INTERPRETATION: Women with type 1 diabetes have a roughly 40% greater excess risk of all-cause mortality, and twice the excess risk of fatal and nonfatal vascular events, compared with men with type 1 diabetes. FUNDING: None.

Obesity related risk of sudden cardiac death in the atherosclerosis risk in communities study.

OBJECTIVE: To examine the association of body mass index (BMI), waist circumference (WC) and waist hip ratio (WHR) with sudden cardiac death (SCD) in community dwelling individuals. METHODS: Data from a multicentre, prospective, cohort study of 14 941 men and women (African American, and white), aged 45-64 years, participating in the Atherosclerosis Risk in Communities study was analysed. Obesity measures were assessed at baseline (1987-1989). SCD was adjudicated by a committee. RESULTS: At enrolment mean±SD age of the participants was 54±6 years (55% female; 26% African American). During 12.6±2.5 years of follow-up, 253 SCD occurred (incidence rate 1.34/100 person-years). The association between obesity and SCD differed by smoking status (interaction p≤0.01). In models adjusting for age, sex, race, study centre and education level, SCD risk was positively associated (p<0.001) with BMI, WC and WHR in non-smokers, but not in smokers. WHR was more strongly associated with SCD in non-smokers than was BMI or WC (HR per SD increment (95% CI) 2.00 (1.65 to 2.42); 1.34 (1.15 to 1.56) and 1.49 (1.28 to 1.74), respectively). After adjustment for potential mediators (hypertension, diabetes, lipid profile, prevalent coronary heart disease, heart failure, and LV hypertrophy), non-smokers in the highest WHR category (>0.95 in women; >1.01 in men) had double the risk of SCD (HR 2.03, 95% CI 1.19 to 3.46; incidence rate 1.43/1000 person-years) versus those with normal WHR. CONCLUSIONS: General obesity is associated with increased risk of SCD in middle-aged, non-smoking individuals, mediated by traditional cardiovascular risk factors. Central obesity, however, is independently associated with SCD by pathways that remain to be elucidated.

A comparison of risk factors for mortality from heart failure in Asian and non-Asian populations: an overview of individual participant data from 32 prospective cohorts from the Asia-Pacific Region.

BACKGROUND: Most of what is known regarding the epidemiology of mortality from heart failure (HF) comes from studies within Western populations with few data available from the Asia-Pacific region where the burden of heart failure is increasing. METHODS: Individual level data from 543694 (85% Asian; 36% female) participants from 32 cohorts in the Asia Pacific Cohort Studies Collaboration were included in the analysis. Adjusted hazard ratios (HR) and 95% confidence intervals (CI) for mortality from HF were estimated separately for Asians and non-Asians for a quintet of cardiovascular risk factors: systolic blood pressure, diabetes, body mass index, cigarette smoking and total cholesterol. All analyses were stratified by sex and study. RESULTS: During 3,793,229 person years of follow-up there were 614 HF deaths (80% Asian). The positive associations between elevated blood pressure, obesity, and cigarette smoking were consistent for Asians and non-Asians. There was evidence to indicate that diabetes was a weaker risk factor for death from HF for Asians compared with non-Asians: HR 1.26 (95% CI: 0.74-2.13) versus 3.04 (95% CI 1.76-5.25) respectively; p for interaction = 0.022. Additional adjustment for covariates did not materially change the overall associations. There was no good evidence to indicate that total cholesterol was a risk factor for HF mortality in either population. CONCLUSIONS: Most traditional cardiovascular risk factors including elevated blood pressure, obesity and cigarette smoking appear to operate similarly to increase the risk of death from HF in Asians and non-Asians populations alike.

Smoking behavior and lung cancer in a biracial cohort: the Atherosclerosis Risk in Communities study.

BACKGROUND: In the U.S., the incidence of lung cancer varies by race, with rates being highest among black men. There are marked differences in smoking behavior between blacks and whites, but little is known regarding how these differences contribute to the racial disparities in lung cancer. PURPOSE: To compare the lung cancer risk associated with smoking in 14,610 blacks and whites in the prospective cohort Atherosclerosis Risk in Communities study. METHODS: Smoking characteristics were ascertained at baseline and three follow-up visits in 1990-1992, 1993-1995, and 1996-1998 (response rates were 93%, 86%, and 80%, respectively), as well as from annual telephone interviews. Data were analyzed in the fall of 2012. Multivariable-adjusted proportional hazards models were used to calculate hazard ratios and 95% CIs for lung cancer. RESULTS: Over 20 years of follow-up (1987-2006), 470 incident cases of lung cancer occurred. Lung cancer incident rates were highest in black men and lowest in black women. However, there was no evidence to support racial differences in the associations of smoking status, intensity, or age at initiation with lung cancer risk (all p(interaction)≥0.25). The hazard ratio for those who started smoking at age ≤12 versus >22 years was 3.03 (95% CI=1.62, 5.67). Prolonged smoking cessation (≥10 years) was associated with a decrease in lung cancer risk, with equivalent benefits in whites and blacks, 84% and 74%, respectively (p(interaction)=0.25). CONCLUSIONS: Smoking confers similar lung cancer risk in blacks and whites.

The association of spousal smoking status with the ability to quit smoking: the Atherosclerosis Risk in Communities Study.

Smoking is the leading cause of preventable death in the United States. Studies have shown that smoking status tends to be concordant within spouse pairs. This study aimed to estimate the association of spousal smoking status with quitting smoking in US adults. We analyzed data from 4,500 spouse pairs aged 45-64 years from the Atherosclerosis Risk in Communities Study cohort, sampled from 1986 to 1989 from 4 US communities and followed up every 3 years for a total of 9 years. Logistic regression with generalized estimating equations was used to calculate the odds ratio of quitting smoking given that one's spouse is a former smoker or a current smoker compared to a never smoker. Among men and women, being married to a current smoker decreased the odds of quitting smoking (for men, odds ratio (OR) = 0.37, 95% confidence interval (CI): 0.29, 0.46; for women, OR = 0.54, 95% CI: 0.43, 0.68). Among women only, being married to a former smoker increased the odds of quitting smoking (OR = 1.26, 95% CI: 1.04, 1.53). In conclusion, spouses of current smokers are less likely to quit, whereas women married to former smokers are more likely to quit. Smoking cessation programs and clinical advice should consider targeting couples rather than individuals.

Do smoking habits differ between women and men in contemporary Western populations? Evidence from half a million people in the UK Biobank study.

OBJECTIVES: Several studies have shown that smoking may confer a greater excess risk for chronic diseases in women compared with men. The reasons for this excess risk of smoking in women are unclear, yet sex differences in smoking habits may play a role. We, thus, characterised sex differences in smoking habits in a contemporary Western population. DESIGN: Cross-sectional population-based study. SETTING: UK Biobank Resource. PARTICIPANTS: 499,797 (54% women) individuals with data on smoking habits. MAIN OUTCOME MEASURES: Women-to-men prevalence ratios in smoking status, and the women-minus-men mean difference in age at smoking initiation, number of cigarettes smoked daily and age at smoking cessation in 5-year birth cohort bands. RESULTS: The women-to-men ever-smoking ratio ranged from 0.57 in the oldest to 0.87 in the youngest birth cohort. In the oldest cohort, born 1935-1939, women started smoking 1.9 years (95% CI 1.7 to 2.1) later than did men, but in those born after 1959 there was no difference in the age at initiation. The oldest women smoked 5.3 (95% CI 4.7 to 5.9) cigarettes per day fewer than did the oldest men, compared with 2.0 (95% CI 1.7 to 2.3) fewer cigarettes smoked per day in the youngest, born 1965-1969. Among quitters, women born before 1945 were, on average, 1.5 years older than their male contemporaries, but this differential was 1 year or less among people born after 1949. CONCLUSIONS: Differences in smoking behaviour between women and men have decreased over time. Even past differentials are unlikely to explain the increased susceptibility to smoking-related chronic disease in women compared with men that has previously been observed. Future studies are required to determine whether sex differences in the physiological and biological effects of smoking are responsible for the differential impact of smoking on health in women and men.

A comparative analysis of risk factors and stroke risk for Asian and non-Asian men: the Asia Pacific cohort studies collaboration.

BACKGROUND: The risk of stroke is high in men among both Asian and non-Asian populations, despite differences in risk factor profiles; whether risk factors act similarly in these populations is unknown. AIM: To study the associations between five major risk factors and stroke risk, comparing Asian with non-Asian men. METHODS: We obtained data from the Asia Pacific Cohort Studies Collaboration, a pooled analysis of individual participant data from 44 studies involving 386 411 men with 9·4 years follow-up. Using cohorts from Asia and Australia/New Zealand Cox models were fitted to estimate risk factor associations for ischemic and haemorrhagic stroke. RESULTS: We identified significant, positive associations between all five risk factors and risk of ischemic stroke. The associations between body mass index, smoking, and diabetes with ischemic stroke were comparable for men from Asia and Australia/New Zealand. The association between systolic blood pressure and ischemic stroke was stronger for Asian than Australia/New Zealand cohorts, whereas the reverse was true for total cholesterol. For haemorrhagic stroke, only systolic blood pressure and smoking were associated with increased risk, although the relationship with systolic blood pressure was significantly stronger for men from Asia than Australia/New Zealand (P interaction = 0·03), whereas the reverse was true for smoking (P interaction = 0·001). There was an inverse trend of total cholesterol with haemorrhagic stroke, significant only for Asian men. CONCLUSIONS: Men from the Asia-Pacific region share common risk factors for stroke. Strategies aimed at lowering population levels of systolic blood pressure, total cholesterol, body mass index, smoking, and diabetes are likely to be beneficial in reducing stroke risk, particularly for ischemic stroke, across the region.

Smoking as a risk factor for stroke in women compared with men: a systematic review and meta-analysis of 81 cohorts, including 3,980,359 individuals and 42,401 strokes.

BACKGROUND AND PURPOSE: It is currently unknown whether the excess risk of stroke by smoking is the same for women and men. We performed a systematic review and meta-analysis to estimate the effect of smoking on stroke in women compared with men. METHODS: PubMed MEDLINE was systematically searched for prospective population-based cohort studies published between January 1, 1966, and January 26, 2013. Studies that presented sex-specific estimates of the relative risk of stroke comparing current smoking with nonsmoking and its associated variability were selected. The sex-specific relative risks and their ratio (RRR), comparing women with men, were pooled using random-effects meta-analysis with inverse variance weighting. Similarly, the RRR for former versus never smoking was pooled. RESULTS: Data from 81 prospective cohort studies that included 3,980,359 individuals and 42,401 strokes were available. Smoking was an independent risk factor for stroke in both sexes. Overall, the pooled multiple-adjusted RRR indicated a similar risk of stroke associated with smoking in women compared with men (RRR, 1.06 [95% confidence interval, 0.99-1.13]). In a regional analysis, there was evidence of a more harmful effect of smoking in women than in men in Western (RRR, 1.10 [1.02-1.18)] but not in Asian (RRR, 0.97 [0.87-1.09]) populations. Compared with never-smokers, the beneficial effects of quitting smoking among former smokers on stroke risk were similar between the sexes (RRR, 1.10 [0.99-1.22]). CONCLUSIONS: Compared with nonsmokers, the excess risk of stroke is at least as great among women who smoke compared with men who smoke.

Relation of serum phosphorus levels to the incidence of atrial fibrillation (from the Atherosclerosis Risk In Communities [ARIC] study).

High serum phosphorus levels have been linked with vascular calcification and greater cardiovascular morbidity and mortality. We assessed whether serum phosphorus was associated with the atrial fibrillation (AF) incidence in a large community-based cohort in the United States. Our analysis included 14,675 participants (25% black, 45% men) free of AF at baseline (1987 to 1989) and with measurements of fasting serum phosphorus from the Atherosclerosis Risk In Communities (ARIC) study. The incidence of AF was ascertained through the end of 2008 from study visit electrocardiograms, hospitalizations, and death certificates. Cox proportional hazard models were used to estimate the hazard ratios of AF by the serum phosphorus levels, adjusting for potential confounders. During a median follow-up of 19.7 years, we identified 1,656 incident AF cases. Greater serum phosphorus was associated with a greater AF risk: the hazard ratio of AF with a 1-mg/dl increase in serum phosphorus was 1.13 (95% confidence interval 1.02 to 1.26). No significant interaction was seen by race (p = 0.88) or gender (p = 0.51). The risk of AF was increased in association with greater serum phosphorus in those with an estimated glomerular filtration rate of ≥90 ml/min/1.72 m(2) but not among those with an estimated glomerular filtration rate of <90 ml/min/1.72 m(2). The total corrected calcium levels were not related to AF risk; however, greater levels of the calcium-phosphorus product were associated with greater AF risk. In conclusion, in the present large population-based study, greater levels of serum phosphorus and the related calcium-phosphorus product were associated with a greater incidence of AF.