Secondhand smoke as an acute threat for the cardiovascular system: a change in paradigm

Impact of Total Indoor Smoking Ban on Cardiovascular Disease Hospitalizations and Mortality: The Case of Chile

INTRODUCTION

The harmful effects of first and secondhand smoking are well-established. Smoke-free laws aim at protecting nonsmokers. This study aimed to assess the impact of the 2013 total ban on indoor smoking in Chile on hospitalizations and deaths of major cardiovascular events.

AIMS AND METHODS

The logarithm of the monthly hospitalization and death rates, standardized by age for every 100 000 inhabitants, were estimated for ischemic heart disease, acute myocardial infarction, strokes, and a composite outcome of ischemic heart diseases (which includes acute myocardial infarction) and strokes. In addition, interrupted time series with synthetic control groups were used to assess changes in levels and trends after the intervention.

RESULTS

The total ban on indoor smoking caused significant reductions in death rates for the three diseases studied for age groups above 20 years old. In addition, there were substantial decreases in the post-intervention hospitalization rates for ischemic heart disease: for the 20-44 age group, the decrease was 8.7% compared to the pre-intervention period (p < .01). In comparison, such a reduction was 4% (p < .01) for the ≥65 age group. For acute myocardial infarction, the decrease was 11.5% (p < .01) for the 20-44 age group, while for stroke, it was a 1.2% (p < .01) decrease for the total population. It is estimated that the smoking ban averted 15.6% of the deaths compared with the synthetic control groups.

CONCLUSIONS

The implementation of total smoke-free environments in Chile contributed to the reduction of mortality for main cardiovascular diseases. This study provides additional evidence of causality linking the policy to health outcomes.

IMPLICATIONS

The total indoor smoking ban significantly affected age-standardized hospitalization and deaths. The number of deaths averted by this policy is estimated at approximately 4758 and 5256 for IHD and stroke, respectively, during the 2013-2017 period (15.6% fewer deaths than predicted by the synthetic control groups). The study contributes to the body of evidence that supports total indoor smoking bans.

An Association Between State Laws Limiting Local Control and Community Smoke-Free Indoor Air in the United States

This study examines the association between state laws limiting local control (preemption laws) and local smoke-free policies. We utilized policy data from the American Nonsmokers' Rights Foundation. The primary outcome variable is the presence of a "100% smoke-free policy," across any of 4 indoor settings: workplaces, restaurants, bars, and gaming venues. We employed generalized structural equation modeling to investigate the relationship between state laws pre-empting smoke-free indoor air regulation and local adoption of policies requiring smoke-free air in any public venues, or for specific venues, adjusting for sociodemographic characteristics. Our findings reveal a significant association between state preemption laws and the presence of a local 100% smoke-free indoor policy as of 2023. In states with preemption laws, cities were less likely to have a 100% smoke-free indoor policy at any venue than cities in states without preemption laws (OR = 0.07, 95% CI = 0.05-0.10). When considering specific smoke-free venues, cities in states with preemption laws were less likely to have a 100% smoke-free indoor policy covering workplaces (OR = 0.05, 95% CI = 0.03-0.09), restaurants (OR = 0.04, 95% CI = 0.02-0.07), bars (OR = 0.04, 95% CI = 0.03-0.08), and gaming venues (OR = 0.03, 95% CI = 0.01-0.09) compared to cities in states without preemption laws. Our study suggests that state preemption laws limit local decision-making and the implementation of public health policies focused on tobacco harms.

A Comprehensive Review on the Impacts of Smoking on the Health of an Individual

Long-term smoking for several years has been known to cause severe ailments in humans from the beginning. Even after knowing that this dangerous addiction is a life-threatening deal, still, ironically, the prevalence of smoking is more or less not getting reduced to a desirable extent. Those who smoke are becoming miserable because of their habit of smoking. Still, on the other hand, due to passive smoking, many more innocent lives are also adversely affected for no fault. This aspect of smoking, i.e., passive or second-hand smoking, is a fearful complication of smoking which is seldom seen with other modes of addiction. Time and again, numerous researches have highlighted the adverse effects of smoking on the human body and the interference it does bring in one's life. Smoking contributes to the deterioration of many preexisting ailments and depletes many valuable aspects of the human body. Smoking thus has a devastating effect on almost all of the tissues of our body and thus exerts its effect on nearly all the major organs. This review article is made by analysing various findings from many researches conducted across the globe by having a thorough search of Pubmed database, which in turn is the main methodology of the article. This review article aims to provide a simple and subtle understanding of the ill effects of smoking on the human body by serving the readers with a readymade platter of comprehensive knowledge about smoking coupled with efforts to eliminate the associated myths.

Effects of chronic secondhand smoke exposure on cardiovascular regulation and the role of soluble epoxide hydrolase in mice

Background: Secondhand smoke (SHS) is a significant risk factor for cardiovascular morbidity and mortality with an estimated 80% of SHS-related deaths attributed to cardiovascular causes. Public health measures and smoking bans have been successful both in reducing SHS exposure and improving cardiovascular outcomes in non-smokers. Soluble epoxide hydrolase (sEH) inhibitors have been shown to attenuate tobacco exposure-induced lung inflammatory responses, making them a promising target for mitigating SHS exposure-induced cardiovascular outcomes. Objectives: The objectives of this study were to determine 1) effects of environmentally relevant SHS exposure on cardiac autonomic function and blood pressure (BP) regulation and 2) whether prophylactic administration of an sEH inhibitor (TPPU) can reduce the adverse cardiovascular effects of SHS exposure. Methods: Male C57BL/6J mice (11 weeks old) implanted with BP/electrocardiogram (ECG) telemetry devices were exposed to filtered air or 3 mg/m3 of SHS (6 hr/d, 5 d/wk) for 12 weeks, followed by 4 weeks of recovery in filtered air. Some mice received TPPU in drinking water (15 mg/L) throughout SHS exposure. BP, heart rate (HR), HR variability (HRV), baroreflex sensitivity (BRS), and BP variability were determined monthly. Results: SHS exposure significantly decreased 1) short-term HRV by ∼20% (p < 0.05) within 4 weeks; 2) overall HRV with maximum effect at 12 weeks (-15%, p < 0.05); 3) pulse pressure (-8%, p < 0.05) as early as week 4; and 4) BRS with maximum effect at 12 weeks (-11%, p < 0.05). Four weeks of recovery following 12 weeks of SHS ameliorated all SHS-induced cardiovascular detriments. Importantly, mice exposed to TPPU in drinking water during SHS-related exposure were protected from SHS cardiovascular consequences. Discussion: The data suggest that 1) environmental relevant SHS exposure significantly alters cardiac autonomic function and BP regulation; 2) cardiovascular consequences from SHS can be reversed by discontinuing SHS exposure; and 3) inhibiting sEH can prevent SHS-induced cardiovascular consequences.

Regulation of endothelial function by cigarette smoke and next-generation tobacco and nicotine products

Cigarette smoking is the most important avoidable cardiovascular risk factor. It causes endothelial dysfunction and atherosclerosis and increases the risk of its severe clinical complications like coronary artery disease, myocardial infarction, stroke, and peripheral artery disease. Several next-generation tobacco and nicotine products have been developed to decrease some of the deleterious effects of regular tobacco smoking. This review article summarizes recent findings about the impact of cigarette smoking and next-generation tobacco and nicotine products on endothelial dysfunction. Both cigarette smoking and next-generation tobacco products lead to impaired endothelial function. Molecular mechanisms of endothelial dysfunction like oxidative stress, reduced nitric oxide availability, inflammation, increased monocyte adhesion, and cytotoxic effects of cigarette smoke and next-generation tobacco and nicotine products are highlighted. The potential impact of short- and long-term exposure to next-generation tobacco and nicotine products on the development of endothelial dysfunction and its clinical implications for cardiovascular diseases are discussed.

Pre- and postnatal exposure to secondhand tobacco smoke and cardiometabolic risk at 12 years: Periods of susceptibility

BACKGROUND

To identify periods of heightened susceptibility to the association of secondhand tobacco smoke (SHS) exposure with cardiometabolic (CM) risk at age 12 years.

METHODS

We used data from 212 adolescents from the HOME Study, a prospective pregnancy and birth cohort in Cincinnati, OH. Using multiple informant models, we estimated associations of maternal serum cotinine (mean of concentrations at 16 and 26 weeks of pregnancy) and children's serum cotinine concentrations (mean of concentrations at ages 1, 2, 3, and 4 years) with a CM risk summary score constructed of five risk components measured at age 12 years. We determined if these associations differed for pre- and postnatal exposure periods, and adolescent's sex.

RESULTS

We found some evidence that the cotinine-outcome associations differed by exposure period and sex. Postnatal, but not prenatal, cotinine was associated with higher CM risk scores and individual CM risk component values (interaction p-values = 0.04 to 0.35). Each 10-fold increase in postnatal cotinine was associated with 0.57 (95% CI: 0.32, 1.45), 0.09 (95% CI: 0.13, 0.31), 0.14 (-0.08, 0.35), 0.07 (95% CI: 0.34, 0.48), and 0.11 (95% CI: 0.04, 0.27) higher CM risk, HOMA-IR, TG to HDL-C ratio, leptin to adiponectin ratio, and visceral fat area. Postnatal cotinine was associated with higher visceral fat area among females but not males (sex × period × cotinine interaction p-value = 0.01).

CONCLUSIONS

Serum cotinine concentrations during the postnatal period had greater influence on adolescent's CM risk compared to the prenatal period, and these associations may be sex-specific. This study reinforces the need for ongoing public health interventions to minimize children's exposure to SHS.

Association between passive smoking and the risk of rheumatoid arthritis: a systematic review and meta-analysis

In order to provide a basis for the prevention of RA, this systematic review and meta-analysis evaluated the association between passive smoking and the risk of developing RA. We searched electronic databases, including PubMed, Cochrane Central Register of Controlled Trials, Web of Science, and Embase, for published literature from the establishment to March 2022. Then we included subject-related cohort studies and case-control studies, and two researchers independently screened and extracted relevant data. Finally, we performed a meta-analysis, cumulative meta-analysis, and dose-response meta-analysis using the Stata software and evaluated the included literature for the level of evidence. This meta-analysis included three case-control and three cohort studies. There was only a small amount of statistical heterogeneity among the studies (I² = 34.9%). According to the study results, the risk of RA was 12% higher in passive smokers than in unexposed individuals. In subgroup analysis, a 12% increase in the prevalence of RA was observed in those exposed to passive smoking in adulthood. The developing RA rate was 34% higher in individuals exposed to passive smoking during childhood than in unexposed individuals. As time progressed and with the inclusion of extensive sample studies in the cumulative meta-analysis, the precision of the overall incidence effect values gradually increased. A dose-response meta-analysis showed no statistical significance that the risk of RA increased with the number of passive smoking years. Passive smoking may relate to the risk of RA, especially in childhood exposures.

Secondhand smoke and the risk of incident cardiovascular disease among never-smoking women

The prospective association between secondhand smoke (SHS) and the risk of incident cardiovascular disease (CVD) remains unclear. This study was the first to examine the association between SHS and risks of ischemic heart disease (IHD), stroke, and total CVD in a large cohort in Asia. The study followed 24,232 never-smoking women aged 40-59 from around Japan (Akita, Iwate, Nagano, Niigata, Ibaraki, Kochi, Nagasaki, and Okinawa prefectures). Their husbands were classified into never, former, and current smokers. After adjustment for age, body mass index, alcohol consumption, histories of hypertension and diabetes mellitus, medication use for hyperlipidemia, menopausal status, and public health center areas, the hazard ratios (HRs) of CVD according to husbands' smoking status were estimated by Cox proportional hazards models. During the 440,360 person-years follow-up, 846 women had total CVDs (103 IHDs, 744 strokes). The proportional hazard assumption was not assured during the total follow-up from 1990 to 2012, but so was then the follow-up of < and ≥ 10 person-years were examined separately. The multivariable HRs (95% confidence intervals) associated with husbands' current versus non-current smoking was 2.02 (1.19-3.45) for IHD, 1.18 (0.98-1.42) for stroke, and 1.25 (1.05-1.49) for total CVD in the follow-up of ≥10 person-years. The SHS from husbands may raise the risk of IHD among middle-aged never-smoking women.

Objectively measured secondhand tobacco smoke and cognitive impairment in disability-free older adults

Previous studies have suggested that exposure to secondhand smoke (SHS) may be associated with greater risk of cognitive impairment. However, no longitudinal study has examined the association of serum cotinine (as objective measure of SHS exposure) and cognitive function in older adults. We used data from 2087 non-smoking adults aged≥65 years participating in the ENRICA-2 cohort and free from limitations in Instrumental Activities of Daily Living. Cognitive function was assessed through the Mini-Mental State Examination (MMSE), the Digit Span Backwards subtest (DSBT), the Luria's motor series subtest from the Frontal Assessment Battery, the Trail Making Test A (TMT-A), the Free and Cued Selective Reminding Test (FCSRT), and the Categorical Verbal Fluency Test (CFT) of the 7 min test. Cross-sectional analyses were performed using multivariable logistic and ordered logistic models, while analyses on changes in cognition over time used multivariable repeated-measures mixed-effects models. Compared to the unexposed, those in the highest exposure group (≥0.161 ng/ml) were more likely to have cognitive impairment (MMSE<24) (odds ratio [OR]:1.64; 95% confidence interval [CI]:1.04-2.60) and lower DSBT scores (OR:1.25; 95%CI:1.00-1.57), as well as a non-significant higher odds of a lower score in the Luria test (OR:1.23; 95%CI:0.92-1.64) or episodic memory impairment (FCSRT<12, OR:1.38; 95%CI:0.90-2.11). In longitudinal analyses, those with baseline cotinine ≥0.161 ng/ml showed an increased risk of cognitive impairment (MMSE<24,OR:2.23; 95%CI:1.14-4.33; p-trend across cotinine categories = 0.028) and decreased DSBT (OR:1.23; 95%CI:1.01-1.51; p-trend across cotinine categories = 0.046). Findings show an increased risk of global cognitive impairment and declines in working memory performance in older adults exposed to SHS. More efforts are needed to protect older adults from SHS in areas not covered by smoke-free legislation.

Effect of Renin-Angiotensin-Aldosterone System Inhibitors on the Rupture Risk Among Hypertensive Patients With Intracranial Aneurysms

BACKGROUND

Mounting experimental evidence supports the concept that the RAAS (renin-angiotensin-aldosterone system) is involved in the pathogenesis of intracranial aneurysm rupture. However, whether RAAS inhibitors could reduce the rupture risk of intracranial aneurysms remains unclear.

METHODS

We performed a chart review of a multicenter, prospectively maintained database of 3044 hypertensive patients with intracranial aneurysms from 20 medical centers in China. The patients were separated into ruptured and unruptured groups. Univariable and multivariable logistical regression analyses were performed to determine the association between the use of RAAS inhibitors and the rupture risk. Sensitivity analyses and subgroup analyses were performed to verify the robustness of the results.

RESULTS

In multivariable analyses, female sex, passive smoking, uncontrolled, or unmonitored hypertension, use of over 2 antihypertensive medications, RAAS inhibitors use, antihyperglycemic agents use, hyperlipidemia, ischemic stroke, and aneurysmal location were independently associated with the rupture risk. The use of RAAS inhibitors was significantly associated with a reduced rupture risk compared with the use of non-RAAS inhibitors (odds ratio, 0.490 [95% CI, 0.402-0.597]; P=0.000). Compared with the use of non-RAAS inhibitors, the use of ACE (angiotensin-converting enzyme) inhibitors (odds ratio, 0.559 [95% CI, 0.442-0.709]; P=0.000) and use of ARBs (angiotensin receptor blockers; odds ratio, 0.414 [95% CI, 0.315-0.542]; P=0.000) were both significantly associated with a reduced rupture risk. The negative association of the rupture risk with RAAS inhibitors was consistent across 3 analyzed data and the predefined subgroups (including controlled hypertension).

CONCLUSIONS

The use of RAAS inhibitors was significantly associated with a decreased rupture risk independent of blood pressure control among hypertensive patients with intracranial aneurysms.

The impact of comprehensive tobacco control policies on cardiovascular diseases in Beijing, China

BACKGROUND AND AIMS

China has a high smoking prevalence, but lacks effective tobacco control interventions. In 2015, comprehensive policies that incorporated all six aspects of MPOWER were implemented in Beijing and were considered the strictest tobacco control policy implemented in China to date. Decreases in the prevalence of active smoking and secondhand smoke (SHS) exposure were observed thereafter. This study aimed to evaluate the impact of Beijing's 2015 tobacco control policy package on cardiovascular diseases (CVDs).

DESIGN

Interrupted time-series study.

SETTING

Beijing, China.

PARTICIPANTS

A total of 17.7 million employees enrolled in Urban Employee Basic Medical Insurance (UEBMI) between January 2013 to June 2017.

INTERVENTIONS

Beijing's 2015 comprehensive tobacco policy package, combining a complete ban on smoking in indoor public places, cessation support, more comprehensive bans on advertising, and tax rises.

MEASUREMENTS

The main outcome was hospital admissions for all CVDs and five major cause-specific CVDs, including ischaemic heart disease (IHD), heart failure (HF), heart rhythm disturbances (HRDs), stroke and other cerebrovascular diseases (CBDs). The absolute number and proportion of reductions in the number of hospital admissions after the policies are reported.

FINDINGS

A total of 419 875 hospital admissions for CVD were identified. In total, 13.4% [95% confidence interval (CI) = 11.5%, 15.3%] of hospital admissions for CVD were averted by the tobacco control policies. For major cause-specific CVDs, significant hospital admission reductions occurred for IHD (5.4%, 95% CI = 2.6%, 8.3%), stroke (21.2%, 95% CI = 17.8%, 24.6%) and other CBDs (25.9%, 95% CI = 20.8%, 31.0%), but not for HF (4.7%, 95% CI = -4.2%, 13.5%) or HRDs (4.7%, 95% CI = -2.9%, 12.3%).

CONCLUSIONS

Beijing's 2015 tobacco control policy package appears to have been associated with a more than 10% reduction in all cardiovascular hospital admissions, including a more than 20% reduction in admissions for cerebrovascular diseases.

Smoking, alcohol and opioids effect on coronary microcirculation: an update overview

Smoking, heavy alcohol drinking and drug abuse are detrimental lifestyle factors leading to loss of million years of healthy life annually. One of the major health complications caused by these substances is the development of cardiovascular diseases (CVD), which accounts for a significant proportion of substance-induced death. Smoking and excessive alcohol consumption are related to the higher risk of acute myocardial infarction. Similarly, opioid addiction, as one of the most commonly used substances worldwide, is associated with cardiac events such as ischemia and myocardial infarction (MI). As supported by many studies, coronary artery disease (CAD) is considered as a major cause for substance-induced cardiac events. Nonetheless, over the last three decades, a growing body of evidence indicates that a significant proportion of substance-induced cardiac ischemia or MI cases, do not manifest any signs of CAD. In the absence of CAD, the coronary microvascular dysfunction is believed to be the main underlying reason for CVD. To date, comprehensive literature reviews have been published on the clinicopathology of CAD caused by smoking and opioids, as well as macrovascular pathological features of the alcoholic cardiomyopathy. However, to the best of our knowledge there is no review article about the impact of these substances on the coronary microvascular network. Therefore, the present review will focus on the current understanding of the pathophysiological alterations in the coronary microcirculation triggered by smoking, alcohol and opioids.

Current Smoking Raises Risk of Incident Hypertension: Hispanic Community Health Study-Study of Latinos

BACKGROUND

Hypertension has been implicated as a smoking-related risk factor for cardiovascular disease but the dose-response relationship is incompletely described. Hispanics, who often have relatively light smoking exposures, have been understudied in this regard.

METHODS

We used data from a 6-year follow-up study of US Hispanic adults aged 18-76 to address the dose-response linking cigarette use with incident hypertension, which was defined by measured blood pressure above 140/90 mm Hg or initiation of antihypertensive medications. Adjustment was performed for potential confounders and mediators, including urinary albumin-to-creatinine ratio which worsened over time among smokers.

RESULTS

Current smoking was associated with incident hypertension, with a threshold effect above 5 cumulative pack-years of smoking (vs. never smokers, hazard ratio for hypertension [95% confidence interval] of 0.95 [0.67, 1.35] for 0-5 pack-years, 1.47 [1.05, 2.06] for 5-10 pack-years, 1.40 [1.00, 1.96] for 10-20 pack-years, and 1.34 [1.09, 1.66] for ≥20 pack-years, P = 0.037). In contrast to current smokers, former smokers did not appear to have increased risk of hypertension, even at the highest cumulative pack-years of past exposure.

CONCLUSIONS

The results confirm that smoking constitutes a hypertension risk factor in Hispanic adults. A relatively modest cumulative dose of smoking, above 5 pack-years of exposure, raises risk of hypertension by over 30%. The increased hypertension risk was confined to current smokers, and did not increase further with higher pack-year levels. The lack of a smoking-hypertension association in former smokers underscores the value of smoking cessation.

Potential Relationship Between Lifestyle Changes and Incidence of Hospital Admissions for Acute Coronary Syndrome During the COVID-19 Lockdown

Aims: To evaluate the impact of lockdown during the COVID-19 pandemic on lifestyle changes of the general population, and on admissions for acute coronary syndrome (ACS).

Methods and Results: All ACS admissions during the COVID-19 lockdown (10 March to 4 May, 2020), in 3 municipalities (3 spoke, and 1 hub hospital), in Southwestern Greece (411,576 inhabitants), were prospectively recorded and compared to the equivalent periods during 2018, and 2019. A telephone survey of 1014 participants was conducted to explore the lifestyle habits of citizens aged ≥35-years-old before and during lockdown. The median ACS incidence rate decreased from 19.0 cases per week in 2018 and 21.5 in 2019 down to 13.0 in 2020 (RR: 0.66 during the Covid-19 lockdown; 95%CI: 0.53–0.82; P = 0.0002). This was driven by a significant reduction of admissions for Non-ST elevation myocardial infarction (NSTEMI) (RR: 0.68; 95%CI: 0.52–0.88; P = 0.0037), mainly in patients with a lower burden of cardiovascular risk factors, as we noticed an inverse association between the reduction of the incidence of ACS during the Covid-19 lockdown period and the number of registered patient risk factors. There was no difference in the rates of STEMI and population-based all-cause mortality across the examined time periods. The telephone survey demonstrated reduction of passive smoking, working hours, alcohol, junk food and salt consumption, and an increase in sleeping hours, mainly in participants with a lower burden of cardiovascular risk factors.

Conclusions: A significant decline in ACS admissions during the COVID-19 lockdown was noted, affecting mainly NSTEMI patients with a lower burden of cardiovascular risk factors. This was accompanied by significant lifestyle changes. Thus, it is tempting to speculate that to some extend the latter might be associated with the observed decline in ACS admissions.

The association between urinary levels of 1,3-butadiene metabolites, cardiovascular risk factors, microparticles, and oxidative stress products in adolescents and young adults

1,3-Butadiene (BD) is a synthetic colorless gas used in the production of synthetic rubber and polymers. Exposure to BD has been reported to increase oxidative stress and accelerate atherosclerosis in vitro and in animal studies. In occupational studies, BD exposure has been linked to cardiovascular disease (CVD). However, no previous research has been reported on whether BD exposure is associated with CVD risk factors and oxidative stress in the general population. We recruited 853 young participants to study the correlation between urinary levels of the BD metabolite, N-acetyl-S-(3,4-dihydroxybutyl)-L-cysteine (DHBMA), CVD risk factors, serum levels of endothelial microparticles and platelet microparticles, and the urinary levels of 8-hydroxydeoxyguanosine (8-OHdG). The results showed the DHBMA levels were positively correlated with low-density lipoprotein-C, carotid intima-media thickness (CIMT), CD31+/CD42a - counts (endothelial apoptosis markers), and urinary 8-OHdG levels. Moreover, DHBMA levels were negatively correlated with CD62 P counts (platelet activation marker). The correlation between DHBMA, CIMT, and 8-OHdG was more evident when the levels of CD31+/CD42a - or CD62 P were above 50%. In conclusion, we reported that the urinary levels of DHBMA were associated with the lipid profile, CIMT, microparticles, and marker of oxidative stress in this young population. Future studies on BD exposure and atherosclerosis are needed.

Comparative Studies of Environmentally Persistent Free Radicals on Total Particulate Matter Collected from Electronic and Tobacco Cigarettes

In the current study, electron paramagnetic resonance (EPR) spectroscopy was employed to measure environmentally persistent free radicals (EPFRs) in the total particulate matter (TPM) of mainstream and sidestream TPM of conventional cigarettes and the TPM of e-cigarettes. Comparable concentrations of EPFRs were detected in both sidestream (8.05 ± 1.32) × 104 pmol/g and mainstream TPM (7.41 ± 0.85) × 104 pmol/g of conventional cigarettes. TPM exposure to air resulted in long-lived oxygen centered, secondary radicals with EPR g values of 2.0041 for mainstream and 2.0044 for sidestream. Surprisingly, despite no combustion process, the TPM from e-cigarettes (menthol flavor of NJOY and V2 brands) also contain EPFRs with g values of 2.0031-2.0033, characteristic of carbon centered radicals, while the radical signal in the vanilla flavor of V2 brand was remarkably similar to semiquinones in cigarette smoke with a higher g value (2.0063). The radical concentration in e-cigarettes was much lower as compared to tobacco TPM. Although the production of ROS generated by e-cigarettes is comparatively lower than ROS generated by conventional cigarettes, EPFRs in e-cigarettes appear to be more potent than those in tobacco TPM with respect to hydroxyl radical generation yield per unit EPFR. EPFRs in e-cigarette TPM may be a potential source of health impacts.

Impact of parental smoking on adipokine profiles and cardiometabolic risk factors in Chinese children

BACKGROUND AND AIMS

The mechanisms by which passive smoking leads to cardiometabolic risks, and the tissues involved still require elucidation. We aimed to evaluate the association of parental smoking exposure (PSE) with the secretion of adipocyte-derived hormones and cardiometabolic risk factors in Chinese children.

METHODS

We included 3150 school children aged 6-18 years from the Beijing Child and Adolescent Metabolic Syndrome (BCAMS) study. Data on PSE and potential confounders were collected. Six adipokines related to insulin resistance and metabolic syndrome (MetS) were measured.

RESULTS

PSE was reported in nearly two-thirds of the children. After adjusting for covariates, including age, sex, pubertal stages, lifestyle factors, and family history, PSE was independently associated with increases of 39.2% in leptin and 3.9% in retinol binding protein-4 and decreases of 11.4% in fibroblast growth factor 21 and 4.6% in adiponectin levels (p < 0.05 for all), plus risks for central obesity (OR 1.59, 95% CI 1.33-1.90), elevated blood pressure (1.22, 1.02-1.46) and MetS (1.43, 1.11-1.85). However, the associations of PSE with hypertension and MetS were abolished when adjusted for adiposity parameters or the above-mentioned adipokine profiles.

CONCLUSIONS

PSE was associated with dysregulation of adipokine levels, which might mediate the development of MetS in early life.

Secondhand Smoke Exposure Among High-Risk Patients in the United States (NHANES 2001-2012): Implications for Clinical Practice

INTRODUCTION

Patients with cancer, cardiovascular disease (CVD), and respiratory disease are susceptible to health consequences related to secondhand smoke (SHS) exposure. This study examined the prevalence, time trends, and correlates of SHS exposure among these patients compared with individuals without these diseases (control).

METHODS

Data were obtained from the 2001-2012 National Health and Nutrition Examination Survey. All adults (≥20 years old) who were nonsmokers and exposed to SHS (serum cotinine level 0.015-10 ng/mL), had cancer (n = 1,440), CVD (congestive heart failure, coronary heart disease, angina, heart attack, or stroke; n = 1,754), respiratory disease (asthma, chronic bronchitis, emphysema; n = 1,444), or none of these diseases (control; n = 11,615) were included in the analysis. Weighted prevalence, weighted second-degree polynomial linear regression of prevalence on year for trend analysis, and multivariable logistic regression analyses were performed with adjustments to the complex survey design.

RESULTS

SHS exposure was the highest among patients with respiratory disease (72.1%), followed by patients with CVD (70.6%), controls (70.4%), and patients with cancer (65.4%). From 2001 to 2012, exposure decreased the most among CVD patients (19.6%), followed by controls (16.0%), cancer patients (14.7%), and respiratory patients (10.0%). Exposed individuals in all groups were more likely to be younger, Black, and less educated. Exposed patients with respiratory disease were more likely to be former smokers (p < .05 for all).

CONCLUSIONS

SHS exposure among these patients is high and comparable to the general population. Strengthening smoke-free policies in all settings is critical. More efforts are needed to address SHS exposure more effectively in clinical care settings.

IMPLICATIONS

Despite the negative health effect of SHS exposure among patients with cancer, CVD, and respiratory disease, modest progress has been made in reducing their exposure. Continued efforts to strengthen smoke-free policies in workplaces, public place, and multiunit housing is critical. In addition, exposure to SHS among these patients seems to be overlooked in clinical care settings. More efforts are needed to address this problem more effectively in health care settings and investigate specific interventions directed at increasing patients' awareness about the risk of exposure to SHS and helping them to reducing their exposure.

Cardiovascular injury induced by tobacco products: assessment of risk factors and biomarkers of harm. A Tobacco Centers of Regulatory Science compilation

Although substantial evidence shows that smoking is positively and robustly associated with cardiovascular disease (CVD), the CVD risk associated with the use of new and emerging tobacco products, such as electronic cigarettes, hookah, and heat-not-burn products, remains unclear. This uncertainty stems from lack of knowledge on how the use of these products affects cardiovascular health. Cardiovascular injury associated with the use of new tobacco products could be evaluated by measuring changes in biomarkers of cardiovascular harm that are sensitive to the use of combustible cigarettes. Such cardiovascular injury could be indexed at several levels. Preclinical changes contributing to the pathogenesis of disease could be monitored by measuring changes in systemic inflammation and oxidative stress, organ-specific dysfunctions could be gauged by measuring endothelial function (flow-mediated dilation), platelet aggregation, and arterial stiffness, and organ-specific injury could be evaluated by measuring endothelial microparticles and platelet-leukocyte aggregates. Classical risk factors, such as blood pressure, circulating lipoproteins, and insulin resistance, provide robust estimates of risk, and subclinical disease progression could be followed by measuring coronary artery Ca2+ and carotid intima-media thickness. Given that several of these biomarkers are well-established predictors of major cardiovascular events, the association of these biomarkers with the use of new and emerging tobacco products could be indicative of both individual and population-level CVD risk associated with the use of these products. Differential effects of tobacco products (conventional vs. new and emerging products) on different indexes of cardiovascular injury could also provide insights into mechanisms by which they induce cardiovascular harm.

Environmental Tobacco Smoke and Cardiovascular Disease

Environmental tobacco smoke (ETS) and its sequelae are among the largest economic and healthcare burdens in the United States and worldwide. The relationship between active smoking and atherosclerosis is well-described in the literature. However, the specific mechanisms by which ETS influences atherosclerosis are incompletely understood. In this paper, we highlight the definition and chemical constituents of ETS, review the existing literature outlining the effects of ETS on atherogenesis and thrombosis in both animal and human models, and briefly outline the public health implications of ETS based on these data.

Exposure to Secondhand Smoke and Arrhythmogenic Cardiac Alternans in a Mouse Model

BACKGROUND

Epidemiological evidence suggests that a majority of deaths attributed to secondhand smoke (SHS) exposure are cardiovascular related. However, to our knowledge, the impact of SHS on cardiac electrophysiology, [Formula: see text] handling, and arrhythmia risk has not been studied.

OBJECTIVES

The purpose of this study was to investigate the impact of an environmentally relevant concentration of SHS on cardiac electrophysiology and indicators of arrhythmia.

METHODS

Male C57BL/6 mice were exposed to SHS [total suspended particles (THS): [Formula: see text], nicotine: [Formula: see text], carbon monoxide: [Formula: see text], or filtered air (FA) for 4, 8, or 12 wk ([Formula: see text]]. Hearts were excised and Langendorff perfused for dual optical mapping with voltage- and [Formula: see text]-sensitive dyes.

RESULTS

At slow pacing rates, SHS exposure did not alter baseline electrophysiological parameters. With increasing pacing frequency, action potential duration (APD), and intracellular [Formula: see text] alternans magnitude progressively increased in all groups. At 4 and 8 wk, there were no statistical differences in APD or [Formula: see text] alternans magnitude between SHS and FA groups. At 12 wk, both APD and [Formula: see text] alternans magnitude were significantly increased in the SHS compared to FA group ([Formula: see text]). SHS exposure did not impact the time constant of [Formula: see text] transient decay ([Formula: see text]) at any exposure time point. At 12 wk exposure, the recovery of [Formula: see text] transient amplitude with premature stimuli was slightly (but nonsignificantly) delayed in SHS compared to FA hearts, suggesting that [Formula: see text] release via ryanodine receptors may be impaired.

CONCLUSIONS

In male mice, chronic exposure to SHS at levels relevant to social situations in humans increased their susceptibility to cardiac alternans, a known precursor to ventricular arrhythmia. https://doi.org/10.1289/EHP3664.

Investigating the association between urinary levels of acrylonitrile metabolite N-acetyl-S-(2-cyanoethyl)-L-cysteine and the oxidative stress product 8-hydroxydeoxyguanosine in adolescents and young adults

Acrylonitrile is a colorless volatile liquid mostly present in tobacco smoke. Acrylonitrile exposure has shown to increase oxidative stress in animal studies; however, there was no previous research in human epidemiology. In this study, 853 subjects were recruited from a cohort of Taiwanese adolescents and young adults to investigate the association between urinary concentrations of the acrylonitrile metabolite N-acetyl-S-(2-cyanoethyl)-L-cysteine (CEMA), the oxidative stress product 8-hydroxydeoxyguanosine (8-OHdG) and cardiovascular disease (CVD) risk factors. The geometric mean (SD) of CEMA and 8-OHdG concentrations were 4.67 (8.61) μg/L and 2.97 (2.14) μg/L, respectively. 10% elevated in CEMA (μg/L) was positively correlated with the change of 8-OHdG levels (μg/L) (β = 0.325, SE = 0.105, P = 0.002) in multiple linear regression analyses. The urinary CEMA was not related to other CVD risk factors. In subpopulation analyses, the association between CEMA and 8-OHdG was evident in all genders, adolescents, homeostasis model assessment of insulin resistance score ≥0.89, and environmental tobacco smokers. In this study, we observed that higher levels of CEMA levels were correlated with increased levels of 8-OHdG in this cohort. Future research on exposure to acrylonitrile and oxidative stress was warranted.

Lead exposure is associated with risk of impaired coagulation in preschool children from an e-waste recycling area

Environmental lead exposure leads to various deleterious effects on multiple organs and systems, including the hematopoietic system. To explore the effects of lead exposure on platelet indices in preschool children from an informal, lead-contaminated electronic waste (e-waste) recycling area, we collected venous blood samples from 466 preschool children (331 from an e-waste area (Guiyu) and 135 from a non-e-waste area (Haojiang)). Child blood lead levels (BLLs) were determined by graphite furnace atomic absorption spectrophotometry, while platelet indices were quantified using a Sysmex XT-1800i hematology analyzer. Higher blood lead levels are observed in e-waste lead-exposed preschool children. Significant relationships between high blood lead levels (exceeding current health limits) and elevated platelet count (PLT), plateletcrit (PCT), mean platelet volume (MPV), and platelet large cell ratio (P-LCR) were also uncovered. Furthermore, the median PLT and PCT levels of children from the exposed group both exceeded the respective recommended maximum reference range value, whereas the reference group did not. Location of child residence in Guiyu and BLLs were both risk factors related to platelet indices. These results suggest that high blood lead exposure from e-waste recycling may increase the risk of an amplified coagulation process through the activation of platelets in preschool children.

Tobacco Smoke Exposure Association With Lipid Profiles and Adiposity Among U.S. Adolescents

PURPOSE

We investigated the association between tobacco smoke exposure (TSE) as measured by serum cotinine and lipoprotein cholesterols and adiposity in adolescents.

METHODS

We performed a secondary analysis of 1999-2012 National Health and Nutrition Examination Survey data including participants 12-19 years old. We examined TSE: unexposed (<.05 ng/mL), passively exposed (.05-2.99 ng/mL), and actively exposed (≥3 ng/mL); lipid profiles: total cholesterol, high-density lipoprotein cholesterol (HDL-C), non-HDL-C, low-density lipoprotein cholesterol (LDL-C), and triglycerides; and adiposity: body mass index z-score (BMIZ), waist circumference (WC), and waist-to-height ratio (WHtR). Covariates were age, sex, race/ethnicity, income, diet, and physical activity. Multiple regression models were used to assess the association between TSE and lipid profile variables separately, and then TSE and adiposity measures separately, adjusting for covariates. We performed logistic regression to examine the association of TSE with body mass index and WHtR classifications.

RESULTS

Of the 11,550 participants, 41.7% were unexposed to tobacco smoke, 40.5% were passively exposed, and 17.8% were actively exposed. Compared with unexposed, participants with active TSE had lower total cholesterol, lower HDL-C, and higher triglycerides; higher BMIZ, higher WC, and higher WHtR; participants with passive TSE had lower HDL-C, higher total cholesterol, and higher LDL-C; higher BMIZ, higher WC, and higher WHtR. Participants actively exposed were at increased odds of being obese or WHtR ≥.65, and those passively exposed were at increased odds of being overweight, obese, or WHtR ≥.65.

CONCLUSIONS

Active TSE and passive TSE are differentially associated with factors within the lipid profile and adiposity, independent of covariates. TSE prevention efforts should start as early as childhood and continue throughout adolescence and adulthood.

Secondhand smoke exposure and risk of incident peripheral arterial disease and mortality: a Scotland-wide retrospective cohort study of 4045 non-smokers with cotinine measurement

BACKGROUND

Active smoking is an important risk factor for all-cause mortality and peripheral arterial disease (PAD). In contrast, published studies on the associations with secondhand smoke (SHS) are limited. The aim of this study was to examine the associations between SHS exposure and incident PAD, as well as mortality, among middle-aged non-smokers.

METHODS

We undertook a retrospective, cohort study using record linkage of the Scottish Health Surveys between 1998 and 2010 to hospital admissions and death certificates. Inclusion was restricted to participants aged > 45 years. Cox proportional hazard models were used to examine the association between SHS exposure and incident PAD (hospital admission or death) and all-cause mortality, with adjustment for potential confounders.

RESULTS

Of the 4045 confirmed non-smokers (self-reported non-smokers with salivary cotinine concentrations < 15 ng/mL), 1163 (28.8%) had either moderate or high exposure to SHS at baseline. In men, high exposure to SHS (cotinine ≥2.7 ng/mL) was associated with increased risk of all-cause mortality (fully adjusted hazard ratio [HR] 1.54, 95% CI 1.07-2.22, p = 0.020) with evidence of a dose-relationship (p for trend = 0.004). In men, high exposure to SHS was associated with increased risk of incident PAD over the first five years of follow-up (fully adjusted HR 4.29, 95% CI 1.14-16.10, p = 0.031) but the association became non-significant over longer term follow-up.

CONCLUSIONS

SHS exposure was independently associated with all-cause mortality and may be associated with PAD, but larger studies, or meta-analyses, are required to confirm the latter.

Exposure to Parental Smoking in Childhood is Associated with High C-Reactive Protein in Adulthood: The Cardiovascular Risk in Young Finns Study

Aim: Children exposed to parental smoking are at increased long-term risk of subclinical atherosclerosis in adulthood. However, it has not been quantified if exposure to parental smoking in childhood is associated with adult systemic inflammation. This study aimed to determine if childhood exposure to parental smoking was associated with high-sensitivity C-reactive protein (hsCRP) in adulthood.

Methods: This longitudinal analysis of 2,511 participants used data from the Cardiovascular Risk in Young Finns Study, a prospective cohort of Finnish children. In 1980 or 1983, parents self-reported their smoking status and serum hsCRP was collected up to 31 years later in adulthood.

Results: Compared with children with non-smoking parents, the relative risk of developing high hsCRP (> 3 mg/L) in adulthood increased among those with 1 or both parents who smoked [relative risk (RR), 1.3; 95%confidence interval (CI), 1.0–1.8] after adjustment for socioeconomic status, cardiovascular risk factors, and smoking status in childhood and adulthood. Moreover, children exposed to mother smoking [RR, 2.4; 95% CI, 1.3–4.2] had highest risk of developing high hsCRP in adulthood compared with those exposed to father smoking [RR, 1.6; 95% CI, 1.2–2.3] and both parents smoking [RR, 1.4; 95% CI, 0.9–2.0].

Conclusion: Our findings suggest that children exposed to parental smoking are at increased risk of having high hsCRP in adulthood. Limiting children's exposure to passive smoking may have long-term benefits on general low-grade inflammation.

Individual and cumulative impacts of fire emissions and tobacco consumption on wildland firefighters' total exposure to polycyclic aromatic hydrocarbons

There is limited information about wildland firefighters' exposure to polycyclic aromatic hydrocarbons (PAHs), being scarce studies that included the impact of tobacco consumption. Thus, this work evaluated the individual and cumulative impacts of firefighting activities and smoking on wildland firefighters' total exposure to PAHs. Six urinary PAH metabolites (1-hydroxynaphthalene (1OHNaph), 1-hydroxyacenaphthene (1OHAce), 2-hydroxyfluorene (2OHFlu), 1-hydroxyphenanthrene (1OHPhen), 1-hydroxypyrene (1OHPy), and 3-hydroxybenzo[a]pyrene (3OHB[a]P)) were quantified by high-performance liquid chromatography with fluorescence detection. Firefighters from three fire stations were characterized and organized in three groups: non-smoking and non-exposed to fire emissions (NSNExp), smoking non-exposed (SNExp), and smoking exposed (SExp) individuals. 1OHNaph+1OHAce were the most predominant OH-PAHs (66-91% ∑OH-PAHs), followed by 2OHFlu (2.8-28%), 1OHPhen (1.3-7%), and 1OHPy (1.4-6%). 3OHB[a]P, the carcinogenicity PAH biomarker, was not detected. Regular consumption of tobacco increased 76-412% ∑OH-PAHs. Fire combat activities promoted significant increments of 158-551% ∑OH-PAHs. 2OHFlu was the most affected compound by firefighting activities (111-1068%), while 1OHNaph+1OHAce presented the more pronounced increments due to tobacco consumption (22-339%); 1OHPhen (76-176%) and 1OHPy (20-220%) were the least influenced ones. OH-PAH levels of SExp firefighters were significantly higher than in other groups, suggesting that these subjects may be more vulnerable to develop and/or aggravate diseases related with PAHs exposure.

Metalloproteinase-9 contributes to endothelial dysfunction in atherosclerosis via protease activated receptor-1

The atherosclerotic process begins when vascular endothelial cells undergo pro-inflammatory changes such as aberrant activation to dysfunctional phenotypes and apoptosis, leading to loss of vascular integrity. Our laboratory has demonstrated that exposure of mice to second hand smoke triggers an increase in expression of metalloproteinase-9. Further, metalloproteinase-9 released by second hand smoke-activated leukocytes may propagate pro-atherogenic alterations in endothelial cells. We have shown that levels of metalloproteinase-9 were increased in the plasma from apolipoprotein E deficient (ApoE-/-) mice exposed to second hand smoke relative to non-exposed controls. Moreover, we have collected data from two different, but complementary, treatments of second hand smoke exposed atherosclerotic mice. Animals received either cell specific metalloproteinase-9 directed siRNA to minimize metalloproteinase-9 expression in neutrophils and endothelial cells, or a pharmacological inhibitor of Bruton's tyrosine kinase which indirectly limits metalloproteinase-9 production in neutrophils. These treatments reduced atherosclerotic changes in mice and improved overall vascular health. We also demonstrated that metalloproteinase-9 could activate endothelial cells and induce their apoptosis via cleavage of protease activated receptor-1. In summary, better understanding of metalloproteinase-9's pathogenic capabilities as well as novel signaling pathways involved may lead to development of treatments which may provide additional benefits to atherosclerosis patients with a history of second hand smoke exposure.

Thirdhand Smoke: New Evidence, Challenges, and Future Directions

Thirdhand smoke (THS) is the contamination that persists after secondhand tobacco smoke has been emitted into air. It refers to the tobacco-related gases and particles that become embedded in materials, such as the carpet, walls, furniture, blankets, and toys. THS is not strictly smoke, but chemicals that adhere to surfaces from which they can be released back into the air, undergo chemical transformations and/or accumulate. Currently, the hazards of THS are not as well documented as the hazards of secondhand smoke (SHS). In this Perspective, we describe the distribution and chemical changes that occur as SHS is transformed into THS, studies of environmental contamination by THS, human exposure studies, toxicology studies using animal models and in vitro systems, possible approaches for avoiding exposure, remediation of THS contamination, and priorities for further research.

Association between secondhand smoke and glycemic control in adult diabetes patients

Diabetes is a major chronic disease, and many studies have shown an association between diabetes with severe complications and certain causes of diabetes, including secondhand smoke. Smoking has been considered a significant issue around the world, and research has been conducted on its relationship with diseases including diabetes. However, previous studies have focused on the onset of diabetes, rather than glycemic control in patients with diabetes. Thus, this study aims to provide evidence of a relationship between secondhand smoke and glycemic control. We conducted a cross-sectional study using data from the Korea National Health and Nutrition Examination Survey (2007-2014). We included 1168 male and 1248 female survey participants. Exposure to secondhand smoke at home and/or at workplaces was considered the primary independent variable, and glycemic control was represented by HbA1c levels. Chi-squared tests and logistic regression analysis were performed to evaluate the association. A significant association was found between secondhand smoke and glycemic control (male at home, odds ratio [OR]: 0.36, 95% confidence interval [CI]: 0.14-0.90; female at both locations, OR: 0.29, 95% CI: 0.11-0.74). The sub-group analysis showed a negative association of diabetes management with secondhand smoke in both sexes, regardless of income status or healthy/unhealthy behaviors. Exposure to secondhand smoke at home was revealed as a risk factor for poor glycemic control. Thus, healthcare providers should help diabetes patients to avoid secondhand smoke by educating them on the dangers of secondhand smoke.

Impact of Smoking on Circulating Cardiac Troponin I Concentrations and Cardiovascular Events in the General Population: The HUNT Study (Nord-Trøndelag Health Study)

BACKGROUND

Both tobacco smoking and circulating cardiac troponin I (cTnI) levels are associated with the risk of acute myocardial infarction, heart failure, and cardiovascular death. However, whether cTnI levels differ according to smoking status and whether smoking modifies the prognostic relationship between cTnI and outcomes remain unclear.

METHODS

Using data from a large, population-based cohort, we assessed the association between smoking and cTnI and the impact of smoking on the associations between cTnI levels and the incidence of acute myocardial infarction, heart failure, and cardiovascular death. cTnI was measured with a high-sensitivity assay in 3824 never smokers, 2341 former smokers, and 2550 current smokers participating in the prospective observational HUNT Study (Nord-Trøndelag Health Study). All subjects were free from known prior cardiovascular disease and diabetes mellitus at baseline.

RESULTS

The age of the participants ranged from 19 to 94 years; 55.5% were women. Current smokers exhibited significantly lower levels of cTnI (median, 2.9 ng/L; interquartile range, 2.0-4.1 ng/L) than never smokers (3.2 ng/L; interquartile range, 2.2-4.7 ng/L; P<0.001) and former smokers (3.4 ng/L; interquartile range, 2.3-5.0 ng/L; P<0.001). This association remained significant after adjustment for potential confounders (B=-0.098; 95% confidence interval, -0.129 to -0.068). We observed an association between increasing concentrations of cTnI and clinical end points in the total study cohort (adjusted hazard ratio per log unit increase in cTnI, 1.41; 95% confidence interval, 1.29-1.54). This association was attenuated for current smokers (hazard ratio, 1.17; 95% confidence interval, 0.98-1.40) and was significantly weaker than in never/former smokers (P for interaction=0.003). Prognostic accuracy, as assessed by C statistics, was significantly lower in current smokers than in never smokers (P<0.001). In addition, cTnI provided no incremental prognostic information to the Framingham Cardiovascular Disease risk score in current smokers (P=0.08).

CONCLUSIONS

Current smoking is associated with lower concentrations of cTnI, suggesting that substances in tobacco smoke may affect cardiomyocyte injury. The association between cTnI levels and cardiovascular end points is stronger in never/former smokers than in current smokers, compatible with the theory that the detrimental cardiovascular impact of current smoking is mediated via mechanisms other than subclinical myocardial injury.

Cigarette Smoking and Oxidative Stress in Patients with Coronary Artery Disease

AIM:

To determine whether cigarette smoking, as a risk factor for CAD, affects (anti)oxidant status.

MATERIAL AND METHODS:

The study included patients with CAD, divided according to their smoking status and the number of cigarettes smoked during a day. Biological markers of oxidative stress (concentration of oxidants and activity of antioxidant enzymes) were measured in all subjects.

RESULTS:

The study included 300 patients with CAD, (average age of 63 ± 11 years), predominantly males. Of the total, 34.0% were active smokers, 23.0% were former smokers, and 43.0% were non-smokers. Most of the active smokers smoked 1-20 cigarettes/day. In terms of concentration of oxidants (MDA and HP) there was not a significant difference between smokers versus non-smokers. As for the activity of antioxidant enzymes (SOD, CAT and GPX), a statistically significant difference was found in the activity of GPX among the active smokers with CAD and the non-smokers with CAD (p = 0.039).

CONCLUSION:

Smoking as a risk factor for CAD is closely associated with increased oxidative stress, and the number of cigarettes smoked plays an important role in increasing the level of oxidative damage and reducing antioxidant defence.

Decrease in mortality rate and hospital admissions for acute myocardial infarction after the enactment of the smoking ban law in São Paulo city, Brazil

BACKGROUND

Smoking restriction laws have spread worldwide during the last decade. Previous studies have shown a decline in the community rates of myocardial infarction after enactment of these laws. However, data are scarce about the Latin American population. In the first phase of this study, we reported the successful implementation of the law in São Paulo city, with a decrease in carbon monoxide rates in hospitality venues.

OBJECTIVE

To evaluate whether the 2009 implementation of a comprehensive smoking ban law in São Paulo city was associated with a reduction in rates of mortality and hospital admissions for myocardial infarction.

METHODS

We performed a time-series study of monthly rates of mortality and hospital admissions for acute myocardial infarction from January 2005 to December 2010. The data were derived from DATASUS, the primary public health information system available in Brazil and from Mortality Information System (SIM). Adjustments and analyses were performed using the Autoregressive Integrated Moving Average with exogenous variables (ARIMAX) method modelled by environmental variables and atmospheric pollutants to evaluate the effect of smoking ban law in mortality and hospital admission rate. We also used Interrupted Time Series Analysis (ITSA) to make a comparison between the period pre and post smoking ban law.

RESULTS

We observed a reduction in mortality rate (-11.9% in the first 17 months after the law) and in hospital admission rate (-5.4% in the first 3 months after the law) for myocardial infarction after the implementation of the smoking ban law.

CONCLUSIONS

Hospital admissions and mortality rate for myocardial infarction were reduced in the first months after the comprehensive smoking ban law was implemented.

Exposure to secondhand smoke and risk of peripheral arterial disease in southern Chinese non-smokers: The Guangzhou Biobank Cohort Study-Cardiovascular Disease Sub-cohort

Objectives

We studied the association between secondhand smoke (SHS) exposure and peripheral arterial disease (PAD) in Chinese non-smokers.

Methods

We conducted a cross-sectional study using baseline data from the Guangzhou Biobank Cohort Study: Cardiovascular Disease Sub-cohort Study (GBCS-CVD). Guangzhou residents aged ≥ 50 years were recruited between 2003 and 2008. Baseline data included measurement of ankle brachial pressure index (ABPI) and self-reported smoking status and SHS exposure. Univariate and multivariate logistic regression analyses were used to analyze the association between SHS and PAD (defined as ABPI < 0.9).

Results

Of the 1507 non-smokers, 24 (1.6%) had PAD. Of these, 12 were men and 12 were women. Exposure to SHS at home of ≥25 h per week was reported by 16.7% of PAD cases compared with 3.8% of those without PAD (χ2 test, p = 0.003). After adjustment for potential confounders, exposure to ≥25 h per week at home was still associated with PAD (adjusted OR 7.86, 95% CI 2.00–30.95, p = 0.003), with suggestion of a dose-response relationship.

Conclusions

Our results extend the US Surgeon General’s 2006 report that SHS exposure is an independent risk factor for PAD. National smoke-free legislation is needed to protect all people from exposure.

Measuring the Effect of Environmental Tobacco Smoke on Lung Function: Results From a Small Observational Investigation of Acute Exposure

OBJECTIVE

Exposure to environmental tobacco smoke (ETS) in smoky venues puts patrons and employees at risk for immediate respiratory symptoms. Although much literature focuses on outcomes associated with chronic ETS exposure, the current study assesses changes in lung function after acute exposure.

METHODS

Ninety-six nonsmoking, healthy adults were exposed to ETS at a bar. Lung function [eg, forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1)] was assessed at baseline, immediately after 3 hours of ETS exposure, and 2 hours after exiting the bar. PM2.5 recordings were also measured.

RESULTS

Repeated-measures analysis of variance found significant decreases in FEV1, FVC and FEF25-75%, and peak expiratory flow after ETS exposure compared with baseline that remained significantly decreased after a 2-hour recovery period.

CONCLUSIONS

Acute exposure to ETS in a natural environment significantly attenuates lung function. A subgroup experienced heightened reductions in lung function.

Time Course of Heart Rate Variability Response to PM2.5 Exposure from Secondhand Smoke

Purpose: Exposure to secondhand smoke (SHS) has been associated with decreased heart rate variability (HRV). However, the time course of this association is unclear. Therefore, the objective of this study was to investigate the association between 15–240 minute SHS-related fine particulate matter (PM_2.5) moving averages and indices of HRV. Methods: With a panel study design, we used personal monitors to continuously measure PM_2.5 and HRV of 35 participants who were exposed to SHS for approximately 6 hours. Results: We observed negative, significant associations between 5-minute HRV indices and 15 minute PM_2.5 moving averages and 240 minute PM_2.5 moving averages: there was a significant (p<0.01) 7.5% decrease in the 5-minute square root of the mean squared differences of successive normal heart beats associated with (RMSSD), and a significant (p<0.01) 14.7% decrease in the 5-minute high frequency (HF) power associated with the 15 minute PM_2.5 moving averages; there was also a significant (p<0.01) 46.9% decrease in the 5-minute RMSSD, and a significant (p<0.01) 77.7% decrease in the 5-minute high frequency (HF) power associated with the 240 minute PM_2.5 moving averages. Conclusions: Our findings that exposure to SHS related PM_2.5 was associated with HRV support the hypothesis that SHS can affect the cardiovascular system. The negative associations reported between short and longer term PM_2.5 and HRV indicate adverse effects of SHS on the cardiovascular system.

Statement of the Spanish Interdisciplinary Cardiovascular Prevention Committee (CEIPC for its Spanish acronym) on the 2012 European Cardiovascular Prevention Guidelines

Based on the two main frameworks for evaluating scientific evidence (SEC and GRADE) European cardiovascular prevention guidelines recommend interventions across all life stages using a combination of population-based and high-risk strategies with diet as the cornerstone of prevention. The evaluation of cardiovascular risk (CVR) incorporates HDL levels and psychosocial factors, a very high risk category, and the concept of age-risk. They also recommend cognitive-behavioural methods (e.g., motivational interviewing, psychological interventions) led by health professionals and with the participation of the patient's family, to counterbalance psychosocial stress and reduce CVR through the institution of positive habits such as a healthy diet, physical activity, smoking cessation, and adherence to treatment. Additionally, public health interventions - such as smoking ban in public areas or the elimination of trans fatty acids from the food chain - are also essential. Other innovations include abandoning antiplatelet therapy in primary prevention and the recommendation of maintaining blood pressure within the 130-139/80-85 mmHg range in diabetic patients and individuals with high CVR. Finally, due to the significant impact on patient progress and medical costs, special emphasis is given to the low therapeutic adherence levels observed. In sum, improving cardiovascular prevention requires a true partnership among the political class, public administrations, scientific and professional associations, health foundations, consumer associations, patients and their families. Such partnership would promote population-based and individual strategies by taking advantage of the broad spectrum of scientific evidence available, from clinical trials to observational studies and mathematical models to evaluate population-based interventions, including cost-effectiveness analyses.

The effect of smoking on carotid intima-media thickness progression rate and rate of lumen diameter reduction

OBJECTIVE

The purpose of the study was to investigate the long-term associations between smoking habits, environmental tobacco smoke exposure (ETS), carotid intima-media thickness (IMT) progression rate, and rate of lumen diameter reduction in the carotid artery during a 16-year follow-up. Another objective was to investigate if an effect of smoking on progression rate could be explained by increased low grade inflammation.

METHODS

The study population included 2992 middle-aged men and women in the 1991-1994 (baseline) and the 2007-2012 (re-examination) investigation of the Malmö Diet and Cancer Study cardiovascular cohort. Associations between smoking, progression of carotid IMT and lumen diameter reduction due to plaque protrusion were assessed by linear regression.

RESULTS

IMT progression rates and rate of lumen diameter reduction increased from never smokers with no ETS through former, moderate and heavy smokers, even after adjustment for traditional risk factors (e.g., differences in yearly progression rates (mm/year) of maximal IMT in the carotid bifurcation compared to never smokers; former smokers 0.0074 (95% CI: 0.0018-0.0129), moderate smokers 0.0106 (95% CI: 0.0038-0.0175), and heavy smokers 0.0146 (95% CI: 0.0061-0.0230)). Former smokers showed distinct lowering of progression rates after more than five years since smoking cessation. Smoking and former smoking was associated with increased low grade inflammation, however, the effect of smoking on atherosclerotic progression rate remained fairly unchanged after such adjustment.

CONCLUSION

The effect of smoking and former smoking on carotid IMT progression rates and change in lumen reduction due to plaque protrusion could not be explained by differences in traditional risk factors or low grade inflammation.

Meditative Movement as a Treatment for Pulmonary Dysfunction in Flight Attendants Exposed to Second-Hand Cigarette Smoke: Study Protocol for a Randomized Trial

A study protocol is presented for the investigation of meditative movement (MM) as a treatment for pulmonary dysfunction in flight attendants (FA) who were exposed to second-hand cigarette smoke while flying before the smoking ban. The study will have three parts, some of which will run concurrently. The first is a data gathering and screening phase, which will gather data on pulmonary and other aspects of the health of FA, and will also serve to screen participants for the other phases. Second is an exercise selection phase, in which a variety of MM exercises will be taught, over a 16-week period, to a cohort of 20 FA. A subset of these exercises will be selected on the basis of participant feedback on effectiveness and compliance. Third is a 52-week randomized controlled trial to evaluate the effectiveness of a digitally delivered form of the previously selected exercises on a group of 20 FA, as compared with an attention control group. Outcome measures to be used in all three parts of the study include the 6-min walk test as a primary measure, as well as a range of biomarkers, tests, and questionnaires documenting hormonal, cardio-respiratory, autonomic, and affective state. This study is registered at ClinicalTrials.gov. Identifier: NCT02612389.

Smoking determines the 10-year (2004-2014) prognosis in patients with Acute Coronary Syndrome: the GREECS observational study

Background

Smoking has long been positively associated with the development and progression of coronary heart disease. However, longitudinal cohort studies evaluating smoking habits among cardiac patients as well as the role of socio-demographic factors determining such behaviours are scarce and have been focused on primary care practice. Thus the aim of the present work was to examine the association of active smoking and behaviours and exposure to second-hand smoke, with the 10-year Acute Coronary Syndrome (ACS) prognosis, among cardiovascular patients.

Methods

From October 2003 to September 2004, a sample of six Greek hospitals was selected and almost allconsecutive 2172 ACS patients were enrolled. In 2013–14, the 10-year follow-up was performed in 1918 participants (11 % loss to follow-up). Smoking habits at the time of entry to the study, as well as during the follow-up period were studied using a standard questionnaire.

Results

Patients who had >60 pack-years of smoking had 57.8 % higher ACS mortality and 24.6 % higher risk for any ACS event. Nested model, adjusted only for age and sex, revealed that for every 30 pack-years of smoking increase, the associated ACS risk increased by 13 % (95 % CI 1.03, 1.30, p = 0.001). When further adjusted analysis, including several potential confounders, was applied the tested relationship was still significant (95 %CI 1.03, 1.30, p = 0.09). Accordingly, the risk for fatal ACS events increased by 8 % for every 30 pack-years of smoking increase (95 % CI 1.03, 1.63, p = 0.06). Moreover, 52 % of the patients reported being exposed to secondhand smoke and when further adjustments were made, it was revealed that they had 33 % (95 % CI 1.12, 1.60, p = 0.01) higher risk of having recurrent ACS events.

Conclusions

Active smoking and second-hand smoke among cardiac patients still represent a substantial clinical burden. Thus, smoking cessation policies should be incorporated into the long-term therapeutic management.

Long-term smoking cessation and heart rate dynamics in an aging healthy cohort: Is it possible to fully recover?

AIM

To evaluate the long-term influence of smoking cessation on the regulation of the autonomic cardiovascular system in an aging general population, using the subpopulation of lifelong non-smokers as control group.

METHODS

We analyzed 1481 participants aged ≥50 years from the SAPALDIA cohort. In each participant, heart rate variability and heart rate dynamics were characterized by means of various quantitative analyzes of the inter-beat interval time series generated from 24-hour electrocardiogram recordings. Each parameter obtained was then used as the outcome variable in multivariable linear regression models in order to evaluate the association with smoking status and time elapsed since smoking cessation. The models were adjusted for known confounding factors and stratified by the time elapsed since smoking cessation.

RESULTS

Our findings indicate that smoking triggers adverse changes in the regulation of the cardiovascular system, even at low levels of exposure since current light smokers exhibited significant changes as compared to lifelong non-smokers. Moreover, there was evidence for a dose-response effect. Indeed, the changes observed in current heavy smokers were more marked as compared to current light smokers. Furthermore, full recovery was achieved in former smokers (i.e., normalization to the level of lifelong non-smokers). However, while light smokers fully recovered within the 15 first years of cessation, heavy former smokers might need up to 15-25 years to fully recover.

CONCLUSION

This study supports the substantial benefits of smoking cessation, but also warns of important long-term alterations caused by heavy smoking.

A systematic review of secondhand tobacco smoke exposure and smoking behaviors: Smoking status, susceptibility, initiation, dependence, and cessation

OBJECTIVES

To examine the association between secondhand tobacco smoke exposure (SHSe) and smoking behaviors (smoking status, susceptibility, initiation, dependence, and cessation).

METHODS

Terms and keywords relevant to smoking behaviors and secondhand tobacco smoke exposure were used in a search of the PubMed database. Searches were limited to English language peer-reviewed studies up till December 2013. Included papers: a) had clearly defined measures of SHSe and b) had clearly defined measures of outcome variables of interest. A total of 119 studies were initially retrieved and reviewed. After further review of references from the retrieved studies, 35 studies were finally selected that met all eligibility criteria.

RESULTS

The reviewed studies consisted of thirty-five (89.7%) studies with differing measures of SHSe (including questionnaire and biological measures) and varying definitions of main outcome variables of interest between studies. The majority of the studies (77%) were cross-sectional in nature. The majority of studies found that SHSe was associated with greater likelihood of being a smoker, increased susceptibility and initiation of smoking, greater nicotine dependence among nonsmokers, and poorer smoking cessation.

CONCLUSIONS

The review found positive associations between SHSe and smoking status, susceptibility, initiation and nicotine dependence and a negative association with smoking cessation. In light of design limitations, future prospective and clinical studies are needed to better understand the mechanisms whereby SHSe influences smoking behaviors.

Passive and Active Tobacco Exposure and Children's Lipid Profiles

INTRODUCTION

Despite reductions in smoking rates, exposure to cigarette smoke remains common among US children and adolescents. In adults, active smoking and secondhand smoke (SHS) exposure have been linked to adverse changes in lipid profiles and increases in inflammatory markers. Evidence that such changes are present before adulthood remains limited, and the extent to which active smoking and SHS exposure affect these cardiovascular measures in children has not been thoroughly assessed.

METHODS

We employed data from 2008 individuals aged 12-19 years from the 2005-2010 National Health and Nutrition Examination Survey. Comparisons of the lipid and inflammatory marker levels among active smokers, those exposed to SHS (as determined by serum cotinine levels), and those unexposed to tobacco smoke were made using linear regression with multiple propensity score adjustment.

RESULTS

Compared to unexposed children, lipid and inflammatory marker profiles did not differ among those exposed to SHS exposure. Among active smokers, differences compared to unexposed children were observed in triglyceride levels ( β=8.5 mg/dL, P = .01), the ratio of triglycerides to high-density lipoprotein ( β=0.2, P = .045), and low-density lipoprotein cholesterol ( β=-4.1 mg/dL , P = .03), though these did not reach levels of confirmatory statistical significance.

CONCLUSIONS

After accounting for sociodemographic characteristics and medical comorbidities, serum lipids and markers of systemic inflammation were not associated with SHS exposure. Tobacco smoke exposure in children may require longer durations of compounded effect before serum lipid abnormalities are detected.

IMPLICATIONS

This paper adds detail to the study of secondhand smoke's effects on lipid profiles of children and adolescents. Prior research on this topic for these age groups has been limited, and this study provides national, cross-sectional data to show that both secondhand smoke and active smoking in childhood and adolescence is not associated with changes in lipid profiles or markers of inflammation. Tobacco smoke exposure may require longer durations of compounded effect before abnormalities are detected.

Secondhand Smoking Is Associated With Vascular Inflammation

BACKGROUND

The relative risk for cardiovascular diseases in passive smokers is similar to that of active smokers despite almost a 100-fold lower dose of inhaled cigarette smoke. However, the mechanisms underlying the surprising susceptibility of the vascular tissue to the toxins in secondhand smoke (SHS) have not been directly investigated. The aim of this study was to investigate directly vascular endothelial cell function in passive smokers.

METHODS

Using a minimally invasive method of endothelial biopsy, we investigated directly the vascular endothelium in 23 healthy passive smokers, 25 healthy active smokers, and 23 healthy control subjects who had never smoked and had no regular exposure to SHS. Endothelial nitric oxide synthase (eNOS) function (expression of basal eNOS and activated eNOS [phosphorylated eNOS at serine1177 (P-eNOS)]) and expression of markers of inflammation (nuclear factor-κB [NF-κB]) and oxidative stress (nitrotyrosine) were assessed in freshly harvested venous endothelial cells by quantitative immunofluorescence.

RESULTS

Expression of eNOS and P-eNOS was similarly reduced and expression of NF-κB was similarly increased in passive and active smokers compared with control subjects. Expression of nitrotyrosine was greater in active smokers than control subjects and similar in passive and active smokers. Brachial artery flow-mediated dilation was similarly reduced in passive and active smokers compared with control subjects, consistent with reduced endothelial NO bioavailability.

CONCLUSIONS

Secondhand smoking increases vascular endothelial inflammation and reduces active eNOS to a similar extent as active cigarette smoking, indicating direct toxic effects of SHS on the vasculature.

Immediate effect of passive smoking on microcirculatory flow

OBJECTIVE

Exposure to SHS, as by passive smoking, seems to increase the incidence of cardiovascular events. It has been shown that active smoking of a single cigarette causes an immediate and significant decrease in microcirculatory blood flow velocity, whereas the acute effects of exposure to SHS on microcirculatory flow have as yet not been demonstrated.

METHODS

Healthy nonsmoking volunteers of both genders were studied during acute exposure to SHS of two cigarettes burning up to 10 minutes. Microvessels were examined by in vivo vital capillaroscopy (Capiflow(®)), allowing continuous assessment of CBV.

RESULTS

CBV decreased from 514 mm/sec (CI 383-646) at baseline to 306 mm/sec (CI 191-420) at end of SHS exposure with a further decrease to a nadir of 240 mm/sec (CI 155-325) four minutes after the end of this exposure (p < 0.0001; ANOVA).

CONCLUSIONS

The result of this study shows that passive inhalation of secondhand cigarette smoke induces an immediate and prolonged marked reduction in CBV in nonsmoking healthy volunteers.