Heart disease mortality in nonsmokers living with smokers

Secondhand and thirdhand smoke: a review on chemical contents, exposure routes, and protective strategies

Secondhand smoke (SHS: a mixture of sidestream and mainstream smoke) and thirdhand smoke (THS: made up of the pollutants that settle indoors after smoking in closed environments) are a significant public health concern. SHS and THS contain various chemicals which can be released into the air or settle on surfaces. At present, the hazards of SHS and THS are not as well documented. In this review, we describe the chemical contents of THS and SHS, exposure routes, vulnerable groups, health effects, and protective strategies. The literature search was conducted for published papers on September 2022 in Scopus, Web of Science, PubMed, and Google Scholar databases. This review could provide a comprehensive understanding of the chemical contents of THS and SHS, exposure routes, vulnerable groups, health effects, protective strategies, and future researches on environmental tobacco smoke.

Association of exposure to environmental tobacco smoke at home and risk of mortality among US never smokers by race/ethnicity, education, and income

Environmental tobacco smoke (ETS) increases the risk of mortality among nonsmokers. Yet, few studies have examined this association among racial/ethnic minorities or among people with less education or income. We assessed self-reported ETS exposure at home among never smoking participants (n = 110,945) of the 1991-2010 National Health Interview Surveys. Deaths through 2015 were identified by the National Death Index. Hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause and cause-specific mortality were estimated using Cox proportional hazards regression models with age as the underlying time metric and adjusted for sex, race/ethnicity, education, household income, body mass index, region of residence, and survey year. We further stratified all-cause mortality analyses by race/ethnicity, household income, and education. Relative to no ETS at home, every day exposure was associated with higher risk of all-cause mortality (HR = 1.33, 95%CI: 1.23, 1.45), with similar HRs observed across strata of education and income. HRs were similar among non-Hispanic Black (HR = 1.28, 95%CI: 1.08, 1.53) and non-Hispanic White adults (HR = 1.34, 95%CI: 1.21, 1.48) although somewhat higher among Hispanic adults (HR = 1.65, 95%CI: 1.29, 2.10; P for pairwise comparison = 0.04). ETS exposure at home is an important contributor to mortality across strata of race/ethnicity, education, and income in the US.

Burden of disease from second-hand tobacco smoke exposure at home among adults from European Union countries in 2017: an analysis using a review of recent meta-analyses

Smoke-free legislation reduced second-hand smoke (SHS) exposure in public places, and indirectly promoted private smoke-free settings. Nevertheless, a large proportion of adults is still exposed to SHS at home. The aim of this paper is to quantify the burden of disease due to home SHS exposure among adults in the 28-European Union (EU) countries for year 2017. The burdens by gender from lung cancer, chronic obstructive pulmonary disease (COPD), breast cancer, ischemic heart disease (IHD), stroke, asthma, and diabetes were estimated in an original research analysis using the comparative risk assessment method. Relative risks of death/diseases by gender for adults exposed to SHS at home compared to not exposed ones were estimated updating existing meta-analyses. Prevalence of home SHS exposure by gender was estimated using a multiple imputation procedure based on Eurobarometer surveys. Data on mortality and disability adjusted life years (DALYs) were obtained from the Global Burden of Disease, Injuries and Risk Factors Study. In 2017, 526,000 DALYs (0.36% of total DALYs) and 24,000 deaths (0.46% of total deaths) were attributable to home SHS exposure in the 28-EU countries, mainly from COPD and IHD. South-Eastern EU countries showed the highest burden, with proportion of DALYs/deaths attributable to SHS exposure on total higher than 0.50%/0.70%, whereas northern EU-countries showed the lowest burden, with proportions of DALYs/deaths lower than 0.25%/0.34%. The burden from SHS exposure is still significant in EU countries. More could be done to raise awareness of the health risks associated with SHS exposure at home.

Stretching the stress boundary: Linking air pollution health effects to a neurohormonal stress response

Inhaled pollutants produce effects in virtually all organ systems in our body and have been linked to chronic diseases including hypertension, atherosclerosis, Alzheimer's and diabetes. A neurohormonal stress response (referred to here as a systemic response produced by activation of the sympathetic nervous system and hypothalamus-pituitary-adrenal (HPA)-axis) has been implicated in a variety of psychological and physical stresses, which involves immune and metabolic homeostatic mechanisms affecting all organs in the body. In this review, we provide new evidence for the involvement of this well-characterized neurohormonal stress response in mediating systemic and pulmonary effects of a prototypic air pollutant - ozone. A plethora of systemic metabolic and immune effects are induced in animals exposed to inhaled pollutants, which could result from increased circulating stress hormones. The release of adrenal-derived stress hormones in response to ozone exposure not only mediates systemic immune and metabolic responses, but by doing so, also modulates pulmonary injury and inflammation. With recurring pollutant exposures, these effects can contribute to multi-organ chronic conditions associated with air pollution. This review will cover, 1) the potential mechanisms by which air pollutants can initiate the relay of signals from respiratory tract to brain through trigeminal and vagus nerves, and activate stress responsive regions including hypothalamus; and 2) the contribution of sympathetic and HPA-axis activation in mediating systemic homeostatic metabolic and immune effects of ozone in various organs. The potential contribution of chronic environmental stress in cardiovascular, neurological, reproductive and metabolic diseases, and the knowledge gaps are also discussed. This article is part of a Special Issue entitled Air Pollution, edited by Wenjun Ding, Andrew J. Ghio and Weidong Wu.

Meta-analysis of the association between second-hand smoke exposure and ischaemic heart diseases, COPD and stroke

Background

Second-hand smoke (SHS) is the most important contaminant of indoor air in first world countries. The risks associated with SHS exposure are highly relevant, because many people are regularly, and usually involuntarily, exposed to SHS. This study aims to quantify the effects of SHS exposure. Therefore, its impact on ischaemic heart diseases (IHD), chronic obstructive pulmonary diseases (COPD) and stroke will be considered.

Methods

A systematic literature review was conducted to identify articles dealing with the association between SHS and the three outcomes IHD, COPD and stroke. Overall, 24 articles were included in a meta-analysis using a random effects model. Effect sizes stratified for sex and for both sexes combined were calculated.

Results

The synthesis of primary studies revealed significant effect sizes for the association between SHS exposure and all three outcomes. The highest RR for both sexes combined was found for COPD (RR = 1.66, 95 % CI: 1.38–2.00). The RR for both sexes combined was 1.35 (95 % CI: 1.22–1.50) for stroke and 1.27 (95 % CI: 1.10–1.48) for IHD. The risks were higher in women than in men for all three outcomes.

Conclusions

This is the first study to calculate effect sizes for the association between SHS exposure and the disease outcomes IHD, COPD, and stroke at once. Overall, the effect sizes are comparable with previous findings in meta-analyses and therefore assumed to be reliable. The results indicate the high relevance of public health campaigns and legislation to protect non-smokers from the adverse health effects attributable to SHS exposure.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-2489-4) contains supplementary material, which is available to authorized users.

Environmental tobacco smoke: respiratory and other health effects

Involuntary exposure to environmental tobacco smoke (ETS) is a serious and entirely preventable public health hazard. It has become clear that ETS adversely affects the health of all who breathe its toxins. Independent of active smoking, ETS exposure is a modifiable risk factor for chronic obstructive pulmonary disease. The expanding body of research presented in this article provides evidence that the damaging consequences of ETS reach far beyond the lungs. Having been determined the third leading cause of preventable death in this country, this is a problem that must be addressed aggressively.

The impact of environmental tobacco smoke on women's risk of dying from heart disease: a meta-analysis

OBJECTIVE

To review systematically and analyze the association between environmental tobacco smoke (ETS) exposure and the risk of dying from heart disease in women.

METHODS

We searched the English-language literature using MEDLINE (1966-April 2004), CINAHL, PsychInfo, and bibliographies of selected studies. We included studies that specifically addressed the association of ETS and heart disease mortality in women and had adequate controls and retrievable risk estimates. We looked for either cohort studies or randomized controlled trials. Studies were evaluated independently by two of the authors. Nine cohort studies were finally selected for analysis. We estimated the summary relative risk (RR) and associated 95% confidence intervals (95% CI) using a random-effects model.

RESULTS

Mean follow-up periods for these cohorts ranged from 6 to 39 years. Among non-smoking women, exposure to ETS was associated with a 15% increase in the risk of dying from heart disease compared with nonsmoking women not exposed to ETS (RR = 1.15, 95% CI 1.03-1.28, p < 0.05).

CONCLUSIONS

Among nonsmoking women, exposure to passive smoke increases the risk of dying from heart disease. In accordance with the newly developed guidelines by the American Heart Association for prevention of cardiovascular disease (CVD) in women, we recommend counseling women on reducing or avoiding ETS exposure.

Marijuana use and cessation of tobacco smoking in adults from a community sample

Tobacco smokers are more likely to use marijuana than those who do not smoke tobacco. Little is known about how marijuana use affects the probability of tobacco smoking cessation. This analysis was based on 431 adults less than 45 years of age who reported recent tobacco smoking in the 1981 baseline interview in the household-based Baltimore Epidemiologic Catchment Area study and were re-interviewed 13 years later. At baseline, 41% of the tobacco smokers reported ever use of marijuana, 27% reported use of marijuana in the previous 30 days, and 9% reported daily use of marijuana for 2 weeks or more in the last 30 days. Marijuana users in the past 30 days at baseline were more likely than nonusers to still be using tobacco at follow-up after adjusting for race, educational level and marital status (OR = 1.94, 95% CI = 1.03, 3.63). Daily use of marijuana at baseline was even more strongly related to continued tobacco smoking 13 years later. Difficulty in tobacco cessation might be considered one of the most important adverse effects of marijuana use. Clinicians working with patients who are trying to stop tobacco smoking may be aided by routinely assessing marijuana use history, particularly with the recent increase in co-smoking of marijuana and tobacco.

Smoking and cardiovascular disease

Mainstream and ETS exposure are strong risk factors for cardiovascular disease in men and women. The relationships between smoking and cardiovascular disease result from multiple mechanisms that interact to contribute to atherosclerosis, vascular injury, thrombosis, and vascular dysfunction. We are only now beginning to understand how smoking contributes to the genesis and progression of cardiovascular disease. Because of the complexity of the interactions between nicotine and the components of MSS, ETS, and sidestream smoke with the vasculature, it will take a great deal of time and effort to fully unravel the mechanisms by which smoking contributes to cardiovascular disease. In addition, cardiovascular risk in female smokers is complicated by hormonal variables that may contribute to greater relative risk. It is important that health care providers, educators, and policy makers recognize the changing patterns of smoking and the impact of smoking on cardiovascular disease, and continue campaigns aimed at enhancing smoking cessation in the general population and in teens. Rigorous research is needed on the changing cultural, psychosocial, and environmental factors that influence tobacco use to improve our understanding of racial/ethnic smoking patterns, and identify strategic tobacco control opportunities. The capacity of tobacco control efforts to keep pace with patterns of tobacco use and cessation depends on timely recognition of emerging prevalence and cessation patterns and the resulting development of appropriate community-based programs to address the factors involved. Smoking trends today will determine how heavy the health burden of cardiovascular disease and others will be among communities tomorrow. Programs that aim at early intervention and reflect cultural diversity will be the cornerstone in the battle against tobacco use. Continued interest in research, educational, and prevention efforts are needed to help curb the risk of cardiovascular disease from smoking in men and women.

Medium-sized business employees speak out about smoking

A health promotion study, funded by a state health department to meet objectives 3.4 and 3.11 of Healthy People 2000, was designed to: (1) identify tobacco use; (2) assess employees' beliefs on one's health and family member's health; and (3) assess the type of smoking policies favored. Using the Health Belief Model, it was hypothesized that there were differences in the health beliefs of tobacco users, former users, and never users. A 34-item questionnaire was administered to 1090 employees with a return rate of 603 (55%).

RESULTS

tobacco users perceived weight control and reduction of tension as benefits; they accepted warning label as hazardous but reported smokeless not as harmful; they perceived heart disease and cancer as related to tobacco use; and 62% had tried to quit smoking. Former and never users wanted "total ban policies" while, tobacco users wanted "designated areas" for smoking. All perceived their smoking and environmental tobacco smoke hazardous to their health and the health of family.

Physiological role of L-ascorbic acid in rats exposed x887p6arette smoke

This study clarifies the effect of exposure to cigarette smoke on L-ascorbic acid (AsA) metabolism and on the activities of drug-metabolizing enzymes. Male Wistar rats were used. The test rats (group T) were exposed to side-stream smoke from cigarette for 2 h every day for 25 days. During the experimental period, the excreted amount of AsA in the urine from group T was higher than that from the control group (group C). At the end of the experimental period, the AsA content of the plasma and tissues, the liver cytochrome P-450 content and the activities of drug-metabolizing enzymes in group T were each higher than those in group C.

Case-control study of passive smoking at home and risk of acute myocardial infarction. Argentine FRICAS Investigators. Factores de Riesgo Coronario en América del Sur

OBJECTIVES

We sought to study the relation between passive smoking at home and the risk of acute myocardial infarction (AMI).

BACKGROUND

Previous epidemiologic studies have linked environmental tobacco smoke to an increased risk of coronary heart disease, but the evidence to support this view is not strong enough. To study this issue further, we analyzed the data from a case-control study conducted in Argentina between 1991 and 1994.

METHODS

Case patients included 336 never-smokers with AMI. Control patients were 446 never-smokers admitted to the same network of hospitals with a wide spectrum of acute disorders unrelated to smoking or to known or suspected risk factors for AMI. Data on the smoking habits of the participants' close relatives (spouse and children) were collected by trained interviewers using a structured questionnaire.

RESULTS

Compared with subjects whose relatives had never smoked, the multivariate odds ratios for passive smokers, according to the smoking status of their relatives, were 1.68 (95% confidence interval [CI] 1.20 to 2.37) for one or more relatives who smoked; 1.59 (95% CI 0.85 to 2.96) for a spouse who smoked; 1.24 (95% CI 0.61 to 2.52) for a spouse who smoked 1 to 20 cigarettes/day; 4.03 (95% CI 0.99 to 16.32) for a spouse who smoked >20 cigarettes/day; and 1.80 (95% CI 1.20 to 2.68) for one or more children who smoked. There was a significant interaction between passive smoking and hypercholesterolemia (> or = 240 mg/dl), hypertension, diabetes and family history of MI.

CONCLUSIONS

In never-smokers, passive smoking at home appeared to be associated with the risk of AMI, and approximately 14% of cases in men and 18% of cases in women in this Argentinian cohort are attributable to passive smoking.

Heart disease from passive smoking in the workplace

OBJECTIVES

This review sought to determine whether passive smoking in the workplace has roughly the same association with heart disease as passive smoking at home and to update a previous 1994 review on the effects of home-based passive exposure on the heart.

BACKGROUND

To predict the effects of passive smoking at work on heart disease, public agencies have had to assume that workplace exposure to tobacco smoke was equivalent to home exposure. With the availability of more workplace exposure data, it is now possible to make a direct comparison.

METHODS

The odds ratios and relative risks (RRs) of the eight studies that contained data on workplace exposure (1,699 cases) were arranged in what was believed to be the order of the quality of their tobacco smoke exposure measurements. A meta-analysis was performed to obtain combined RRs. Data from seven new studies on largely home-based exposure and heart disease that were not included in the 1994 review were also evaluated.

RESULTS

The combined RR for the three top-rated workplace studies was 1.50 (95% confidence interval [CI] 1.12 to 2.01). Adding four lower rated studies reduced the RR to 1.35 (95% CI 1.09 to 1.67). Adding the largest study but the one with questionable exposure history reduced the combined RR to 1.18 (95% CI 1.04 to 1.34). Adding the seven new, largely home-based studies increased the home-based morbidity RR to 1.49 (95% CI 1.29 to 1.72) compared with 1.42 in 1994 while leaving the mortality RR unchanged at 1.23 (95% CI 1.14 to 1.32).

CONCLUSIONS

The RRs for heart disease from passive smoking at work are roughly equal to those from home-based exposure.

Passive smoking and coronary heart disease: a brief review

1. Whether passive smoking or environmental tobacco smoke (ETS) can cause coronary heart disease (CHD) is controversial. We have undertaken a comprehensive review of the epidemiological studies regarding the relationship between ETS and CHD. 2. We searched for all original papers and reviews and calculated pooled odds ratio using the Mantel-Haenszel method. 3. Ten prospective studies, nine case-control studies and one cross-sectional study were found. Almost all studies showed positive associations between ETS and CHD and a few were statistically significant, with dose-response relationships being evident. Six review papers calculated pooled estimates of the relative risks, which ranged from 1.23 to 1.51. Other studies also showed that ETS could have other cardiovascular effects. 4. The association observed is likely to be real. The criteria for causation of time sequence, consistency, coherence and biological plausibility are satisfied. We conclude that ETS may cause CHD, particularly in women who have never smoked.

Dietary and lifestyle correlates of passive smoking in Hong Kong, Japan, Sweden, and the U.S.A

From epidemiologic studies in several countries, passive smoking has been associated with increased risk for lung cancer, respiratory diseases, and coronary heart disease. Since the relative risks derived from those studies are weak, i.e. relative risk less than two, we investigated whether poorer diets and less healthy lifestyles might act as confounders and be correlated with having a smoking husband on a cross-cultural basis. Characteristics of never-smoked wives with or without smoking husbands were compared between 530 women from Hong Kong, 13,047 from Japan, 87 from Sweden, and 144 from the U.S. In all four sites, wives with smoking husbands generally ate less healthy diets. They had a tendency to eat more fried food but less fruit than wives with nonsmoking husbands. Other healthy traits, e.g. avoiding obesity, dietary cholesterol and alcohol, or taking vitamins and participating in preventive screening were also less prevalent among wives with smoking husbands. These patterns suggest that never-smoked wives with smoking husbands tend to share the same less healthy dietary traits characteristic of smokers, and to have dietary habits associated with increased risk for lung cancer and heart disease in their societies. These results emphasize the need to take into account the potential confounding effects of diet and lifestyle in studies evaluating the health effects of passive smoking, especially since it is known that the current prevalence rates of smoking among men is indirectly associated with social class and education in affluent urban societies.

A prospective study of passive smoking and coronary heart disease

BACKGROUND

Several epidemiological studies have suggested an association of passive smoking with coronary heart disease (CHD). However, few studies have taken account of exposure to passive smoking in the workplace. Additionally, several studies have been unable to control for the full range of potential confounding factors. We examined prospectively the relationship of passive smoking with risk of CHD in a cohort of women.

METHODS AND RESULTS

The study was carried out in an ongoing prospective cohort of US female nurses, in whom we assessed exposure to passive smoking at home and at work as well as duration of years spent living with someone who smoked regularly. We studied 32046 women 36 to 61 years of age in 1982 who had never smoked and were free of diagnosed CHD, stroke, and cancer. During 10 years of follow-up (1982 to 1992), 152 incident cases of CHD (127 nonfatal myocardial infarction and 25 fatal CHD) occurred. Compared with women not exposed to passive smoking, the relative risks of total CHD-adjusted for a broad range of cardiovascular risk factors-were 1.58 (95% CI, 0.93 to 2.68) among those reporting occasional exposure and 1.91 (95% CI, 1.11 to 3.28) among women reporting regular exposure to passive smoking at home or work. There was no relation apparent between duration of living with a smoker and risk of CHD.

CONCLUSIONS

Despite the fact that exposure to passive smoking was assessed by self-report and only at baseline (as well as other limitations), these data suggest that regular exposure to passive smoking at home or work increases the risk of CHD among nonsmoking women.

Testosterone worsens endothelial dysfunction associated with hypercholesterolemia and environmental tobacco smoke exposure in male rabbit aorta

OBJECTIVES

To assess the effects of interaction of sex hormones, hypercholesterolemia (HC) and environmental tobacco smoke (ETS) exposure on endothelium-dependent relaxation, we examined vascular reactivity in vitro in an animal model of atherogenesis.

BACKGROUND

Animal and human studies indicate the presence of interactions between classic coronary artery disease risk factors and endothelium-dependent relaxation. Sex hormones have also been shown to influence release of endothelium-derived relaxing factor.

METHODS

New Zealand White rabbits were randomized to receive either an HC diet (n = 8) or ETS exposure plus HC diet (n = 8). Eight rabbits receiving a normal diet, without exposure to ETS, served as the control group. The HC diet consisted of 3% soybean oil and 0.3% cholesterol by weight over 13 weeks. The source of ETS was sidestream smoke of 4 cigarettes/15 min, 6 h/day, 5 days/week over 10 weeks in a smoking chamber. Rabbits were killed, and fresh aortic rings were harvested and maintained in oxygenated Krebs solution in an organ bath at 37 degrees C. Rings were precontracted with norepinephrine and exposed to acetylcholine in increasing doses, and isometric tension was recorded. Rings were also exposed to physiologic concentrations (1 nmol/liter) of either 17-beta-estradiol, testosterone or progesterone before pre-contraction with norepinephrine and relaxation with acetylcholine. Endothelium-independent relaxation was studied using nitroglycerin. The surface area of the ring covered by lipids was measured by Sudan IV staining.

RESULTS

HC and ETS significantly reduced endothelium-dependent relaxation (p = 0.01 and p < 0.0005, respectively) and caused atherogenesis (p < 0.0005 and p = 0.047, respectively) but did not affect endothelium-independent relaxation. Incubation with estradiol and estradiol plus progesterone did not influence endothelium-dependent relaxation. Testosterone reduced endothelium-dependent relaxation (p = 0.049) and augmented the endothelial dysfunction associated with ETS exposure and HC (p = 0.03).

CONCLUSIONS

Both HC and ETS are atherogenic and impair endothelial function but do not affect endothelium-independent relaxation. Physiologic levels of estradiol and estradiol plus progesterone do not affect endothelium-dependent relaxation. Physiologic levels of testosterone impair relaxation and augment the endothelial dysfunction associated with ETS exposure and HC.

Influence of worksite environmental tobacco smoke on serum lipoprotein profiles of female nonsmokers

The purpose of this study was to examine the influence of environmental tobacco smoke (ETS) in the workplace on high-density lipoprotein cholesterol (HDL-C), HDL-C subfractions, and apolipoprotein (apo) A-I and apo B in female workers. Premenopausal women free from factors known to influence HDL-C (cigarette smoking, vigorous physical exercise, etc) who were not taking oral contraceptives, were moderate consumers of alcohol, caffeine, and dietary fat, and were between the ages of 21 and 50 years participated in one of two groups: (1) nonsmokers who had never smoked cigarettes and were generally free from ETS exposure (nonsmokers), and (2) nonsmokers who had never smoked but were subjected to concentrated doses of ETS at least 6 hours per day, 4 days per week, for at least 6 consecutive months (ETS-exposed). A third group consisting of current cigarette smokers who smoked a minimum of 20 cigarettes per day for at least the past 5 consecutive years served as smoking control (smokers). Subjects were matched by group as closely as possible with regard to criteria that can influence blood lipoprotein levels. Participants were solicited from taverns and restaurants where they were employed. It was hypothesized that individuals chronically exposed to ETS would demonstrate unfavorable lipoprotein profiles. Results showed that HDL-C, HDL2, and apo A-I were significantly (P < .05) depressed for ETS-exposed and smokers as compared with nonsmokers. Values for ETS-exposed were not different from those for smokers. Total cholesterol, triglycerides, HDL3, and apo B did not differ among the three groups. It was concluded that excessive exposure to ETS in female workers can have deleterious effects on HDL-C, HDL2, and apo A-I in nonsmokers that are similar to effects observed in cigarette smokers. It is possible that these effects increase coronary artery disease (CAD) risk.

Chronic obstructive pulmonary disease in lifelong nonsmokers: results from NHANES

The prevalence of chronic obstructive pulmonary disease was evaluated in 12,980 lifelong nonsmoking adults who participated in one of three National US Health and Nutrition Examination Surveys. Also evaluated were the relationships between chronic obstructive pulmonary disease and age, sex, ethnicity, education, income, and certain environmental and occupational factors. Overall, 4% of men and 5% of women reported physician-diagnosed chronic obstructive pulmonary disease. Prevalence increased with age and with decreasing household income, was higher in Whites than in non-Whites, and was particularly high in Hispanic women. Further research is needed to explain the excess risk for chronic obstructive pulmonary disease in economically disadvantaged nonsmokers, and to assess the role of environmental tobacco smoke in nonsmokers' risk for the disease.

Passive smoking as a cause of heart disease

The effects of passive smoking on ischemic heart disease are reviewed. Short-term exposures of 20 min to 8 h result in increased platelet sensitivity and decreased ability of the heart to receive and process oxygen. Longer term exposure results in plaque buildup and adverse effects on blood cholesterol. The available epidemiology is reviewed, and it is concluded that passive smoking increases the coronary death rate among U.S. never smokers by 20% to 70%. The newest Environmental Protection Agency procedures for estimating deaths from passive smoking, when applied to the epidemiologic results on heart disease and passive smoking, indicate that in 1985 an estimated 62,000 ischemic heart disease deaths in the United States were associated with exposure to environmental tobacco smoke. Clinicians are advised to counsel their patients to avoid tobacco smoke at home, at work and in transportation settings.

Environmental tobacco smoke exposure among Hispanic women of reproductive age

Exposure to environmental tobacco smoke is a potential health risk for women of reproductive age and their children. Household and workplace exposures were estimated for 4256 Hispanic women age 12 to 49 who participated in the Hispanic health and nutrition examination survey. Age-specific household exposure for nonsmokers was 31% to 62% for Mexican-Americans, 22% to 59% for Puerto Ricans, and 40% to 53% for Cuban-Americans. Exposure was significantly high for Puerto Rican and Mexican-American adolescents, 59% and 62%, respectively. Workplace exposure for nonsmokers was 22% to 35% for Mexican-Americans, 28% to 33% for Puerto Ricans, and 33% to 49% for Cuban-Americans. Young Mexican-American and Puerto Rican and all Cuban-American women reported high exposure to environmental tobacco smoke in the home or workplace. Assessment of family living and smoking patterns, understanding cultural values and norms, and household smoking control and cessation strategies that are mutually derived are useful for nurses and Hispanic and Latino populations to meet the environmental tobacco smoke health objectives for the nation.

Coronary heart disease, cancer and mortality in male middle-aged light smokers

We examined the effect of light smoking in relation to incidence of coronary heart disease (CHD) in a general population sample consisting of 6879 men aged 47-55 years and free of previous myocardial infarction (MI) at baseline. After a follow-up of mean duration 11.8 years, 11.0% of men smoking 1-4 cigarettes daily (n = 228) had suffered a major CHD event, compared to 3.7% of non-smokers (n = 2049) [adjusted odds ratio 2.8 (1.7-4.7)]. No further increase in risk was observed in men who smoked more. There was an increasing risk of death from cancer with the number of cigarettes smoked per day. Mortality was increased in all categories of cigarette smokers, particularly among the very heavy smokers, who had a mortality risk of 22% compared to 6% among nonsmokers [adjusted odds ratio 4.4 (2.7-7.1)]. Data from an examination 4 years later considered only those men who stated that their smoking habits were identical on both occasions (n = 3981). Among these subjects the incidence of CHD after a mean period of 7.1 years was 10.6% in men smoking 1-4 cigarettes per day, compared to 2.6% in nonsmokers [adjusted O.R. 4.6 (2.1-10.1)]. No dose-response effect was observed. Even very light cigarette smoking considerably increases the risk of CHD in middle-aged men.

Environmental tobacco smoke: current assessment and future directions

Scientific information on environmental tobacco smoke (ETS) is critically reviewed. Key areas addressed are: differences in chemical composition between mainstream smoke, sidestream smoke, and ETS; techniques for measurement of ETS; epidemiology; in vitro and in vivo toxicology; and chamber and field studies of perceptual or physiological effects. Questions concerning estimation of ETS exposure, suitability of various biomarkers, calculation of lifetime dose, control of confounding variables, use of meta-analysis, and the relationship between ETS concentrations and human responses all emphasize the need for additional research in order to assess potential effects of ETS on health or comfort.

Smoking and the risk of first acute myocardial infarction

When analyzing risk factors for first acute myocardial infarction in the Copenhagen City Heart Study, a large prospective population study of 20,000 men and women, smoking was found to influence risk significantly in a dose-dependent manner, the risk increasing 2% to 3% for each gram of tobacco smoked daily. Risk was particularly associated with inhalation, the risk for inhalers being almost twice that of noninhalers. No difference in risk could be demonstrated between various types of tobacco (pipe, cigar/cheroots, or plain and filtered cigarettes). The risk seemed associated with current smoking only, inasmuch as the duration of the smoking habit was not important. Ex-smokers had the same risk as those who had never smoked regardless of duration of smoking and time elapsed since quitting. Relative excess risk was significantly higher in female smokers than in male smokers, and daily alcohol intake appeared to have some protective effect on the risk of first acute myocardial infarction among heavy smokers.

Passive smoking and the risk of heart attack or coronary death

OBJECTIVES

To estimate the prevalence of passive smoking in an Australian population, the magnitude of risk of myocardial infarction or coronary death associated with passive smoking and the extent to which fibrinogen concentrations might be affected by passive smoking.

DESIGN

A population-based case-control study of myocardial infarction or coronary death and passive smoking, and measurement of fibrinogen in a random sample from the same population.

SETTING AND PARTICIPANTS

Residents of the Lower Hunter Region of New South Wales aged 35-69 years in 1988-1989. Case subjects were all those who suffered myocardial infarction or coronary death. Control subjects were participants in a risk factor prevalence survey.

OUTCOME MEASURES

Myocardial infarction or coronary death, defined by criteria of the WHO MONICA Project, and fibrinogen concentration (measured in controls only).

RESULTS

Prevalence of passive smoking at home was 20% for male case subjects, 13% for male control subjects, 29% for female case subjects and 19% for female control subjects. The corresponding prevalence rates for passive smoking at work were 40%, 44%, 41% and 37%. Odds ratios of myocardial infarction or coronary death for active smokers compared with non-smokers were 4.70 (95% confidence interval [CI], 3.35-6.58) in women and 2.71 (95% CI, 2.07-3.53) in men. For women the odds ratios of myocardial infarction or coronary death for those exposed to passive smoking at home were 2.46 (95% CI, 1.47-4.13) among non-smokers and 1.48 (95% CI, 0.67-3.30) among ex-smokers. For men the odds ratios for passive smoking at home were 0.97 (95% CI, 0.50-1.86) for non-smokers and 1.78 (95% CI, 1.13-2.79) for ex-smokers. The odds ratios for passive smoking at work did not suggest increased risk. Fibrinogen concentrations were generally higher among people exposed to passive smoking at home or work compared with those not exposed but were not as high as concentrations in active smokers.

CONCLUSIONS

Passive smoking increases the risk of coronary heart disease and increased fibrinogen concentration provides a marker of its effect.

Passive smoking and heart disease. Epidemiology, physiology, and biochemistry

The evidence that ETS increases risk of death from heart disease is similar to that which existed in 1986 when the US Surgeon General concluded that ETS caused lung cancer in healthy nonsmokers. There are 10 epidemiological studies, conducted in a variety of locations, that reflect about a 30% increase in risk of death from ischemic heart disease or myocardial infarction among nonsmokers living with smokers. The larger studies also demonstrate a significant dose-response effect, with greater exposure to ETS associated with greater risk of death from heart disease. These epidemiological studies are complemented by a variety of physiological and biochemical data that show that ETS adversely affects platelet function and damages arterial endothelium in a way that increases the risk of heart disease. Moreover, ETS, in realistic exposures, also exerts significant adverse effects on exercise capability of both healthy people and those with heart disease by reducing the body's ability to deliver and utilize oxygen. In animal experiments, ETS also depresses cellular respiration at the level of mitochondria. The polycyclic aromatic hydrocarbons in ETS also accelerate, and may initiate, the development of atherosclerotic plaque. Of note, the cardiovascular effects of ETS appear to be different in nonsmokers and smokers. Nonsmokers appear to be more sensitive to ETS than do smokers, perhaps because some of the affected physiological systems are sensitive to low doses of the compounds in ETS, then saturate, and also perhaps because of physiological adaptions smokers undergo as a result of long-term exposure to the toxins in cigarette smoke. In any event, these findings indicate that, for cardiovascular disease, it is incorrect to compute "cigarette equivalents" for passive exposure to ETS and then to extrapolate the effects of this exposure on nonsmokers from the effects of direct smoking on smokers. These results suggest that heart disease is an important consequence of exposure to ETS. The combination of epidemiological studies with demonstration of physiological changes with exposure to ETS, together with biochemical evidence that elements of ETS have significant adverse effects on the cardiovascular system, leads to the conclusion that ETS causes heart disease. This increase in risk translates into about 10 times as many deaths from ETS-induced heart disease as lung cancer; these deaths contribute greatly to the estimated 53,000 deaths annually from passive smoking. This toll makes passive smoking the third leading preventable cause of death in the United States today, behind active smoking and alcohol.

Passive smoking and 20-year cardiovascular disease mortality among nonsmoking wives, Evans County, Georgia

The association of passive smoking and cardiovascular disease (CVD) mortality was assessed in a cohort of 513 rural, married Black and White women who were disease-free and self-described as never-smokers at baseline in 1960. Over a 20-year period, 76 of 147 total deaths were attributed to CVD. Relative risk estimates adjusted for age, cholesterol, blood pressure, and body mass from proportional hazards models were 1.59 for CVD (95% CI = 0.99, 2.57) and 1.39 (CI = 0.99, 1.94) for all cause mortality among women with husbands who smoked cigarettes.

Community impact of a localized smoking cessation contest

The present study assessed the effectiveness of a localized community contest timed to coincide with a statewide smoking cessation contest. Follow-up interviews were conducted with 218 local contest participants and 198 participants from the statewide contest. Overall cessation impact (participation rate x abstinence) was 0.39 percent for the local contest and 0.09 percent for the statewide contest. Localized community contests offered in conjunction with statewide or national campaigns may represent cost-effective methods of reaching large numbers of smokers.

Deaths from all causes in non-smokers who lived with smokers

Mortality associated with passive smoking was evaluated in a 12-year study of 27,891 White adult smokers and 19,035 never smokers identified in 1963. Death rates were calculated using an estimate of the person-years at risk. Adjusted for age, marital status, education, and quality of housing, the estimated relative risks of death from all causes were 1.17 (approximate 95% confidence interval 1.01, 1.36) for men and 1.15 (1.06, 1.24) for women with passive exposure. These relative risks were similar to those for ex-smokers and for pipe or cigar smokers. Risks increased slightly with level of exposure. The relative risk from passive smoking was greatest for men under age 50 (RR = 2.09, 1.31-3.34). Risks from passive smoking were slightly elevated for several causes among men and women, and may be broader than those previously reported. On the other hand, these small nonspecific increases in death rates may reflect other characteristics of passive smokers that increase mortality.