Secondhand Smoke Exposure and Subclinical Cardiovascular Disease: The Multi-Ethnic Study of Atherosclerosis

Advancements in Cardiovascular Disease Research Affected by Smoking

The harmful substances in tobacco are widely recognized to exert a significant detrimental impact on human health, constituting one of the most substantial global public health threats to date. Tobacco usage also ranks among the principal contributors to cardiovascular ailments, with tobacco being attributed to up to 30% of cardiovascular disease-related deaths in various countries. Cardiovascular disease is influenced by many kinds of pathogenic factors, among them, tobacco usage has led to an increased year by year incidence of cardiovascular disease. Exploring the influencing factors of harmful substances in tobacco and achieving early prevention are important means to reduce the incidence of cardiovascular diseases and maintain health. This article provides a comprehensive review of the effects of smoking on health and cardiovascular diseases.

Documento de consenso sobre tabaquismo y riesgo vascular

Consensus statement on smoking and vascular risk About 22% of the Spanish population are daily smokers. Men are more likely to smoke than women. In Spain, women between 15-25 years of age smoke as much or more than men. Every smoker should be assessed for: physical dependence on nicotine (Fagerström test), social and psychological dependence (Glover Nilsson test), level of motivation to quit (Richmond test), probability of therapy success (Henri-Mondor and Michael-Fiore tests), and stage of behavioral change development (Prochaska and DiClementi). Advice on smoking cessation is highly cost-effective and should always be provided. Smoking is an enhancer of cardiovascular risk because it acts as a pathogen agent in the development of arteriosclerosis and is associated with ischemic heart disease, stroke, and peripheral artery disease. Smoking increases the risk of chronic lung diseases (COPD) and is related to cancers of the lung, female genitalia, larynx, oropharynx, bladder, mouth, esophagus, liver and biliary tract, and stomach, among others. Combined oral contraceptives should be avoided in women smokers older than 35 years of age due to the risk of thromboembolism. In smoking cessation, the involvement of physicians, nurses, psychologists, etc. is important, and their multidisciplinary collaboration is needed. Effective pharmacological treatments for smoking cessation are available. Combined treatments are recommended when smoker's dependence is high. For individuals who are unable to quit smoking, a strategy based on tobacco damage management with a total switch to smokeless products could be a less dangerous alternative for their health than continuing to smoke.

Systemic inflammation mediates the association between environmental tobacco smoke and depressive symptoms: A cross-sectional study of NHANES 2009-2018

BACKGROUND

Depression is associated with both environmental tobacco smoke (ETS) and inflammation. However, whether systemic inflammation mediates the ETS-depression relationship is unclear.

METHODS

We analyzed 19,612 participants from the 2009-2018 National Health and Nutrition Examination Survey (representing approximately 206,284,711 USA individuals), utilizing data of depressive symptoms (assessed by Patient Health Questionnaire-9), blood cotinine level (an ETS biomarker), dietary inflammatory index (DII, assessed by 24-h dietary recall) and inflammation, represented by immune-inflammation index (SII) and systemic inflammation response index (SIRI).

RESULTS

Weighted multivariable logistic regression showed that a higher blood cotinine level is significantly associated with a higher depressive symptoms risk (OR = 1.79, 1.35-2.38). After adjusting for covariates, the effect in smokers (OR = 1.220, 95 % CI: 1.140-1.309) is larger than that in non-smokers (OR = 1.150, 95 % CI: 1.009-1.318). Compared to the lowest level, depressive symptoms risks in participants with the highest level of SII, SIRI and DII are 19 % (OR = 1.19, 1.05-1.35), 15 % (OR = 1.15, 1.01-1.31) and 88 % (OR = 1.88, 1.48-2.39) higher, respectively. Weighted linear regression demonstrated positive correlations of SII (β = 0.004, 0.001-0.006), SIRI (β = 0.009, 0.005-0.012) and DII (β = 0.213, 0.187-0.240) with blood cotinine level. Restricted cubic splines model showed a linear dose-response relationship between blood cotinine and depressive symptoms (Pnon-linear = 0.410), with decreasing risk for lower DII. And SII and SIRI respectively mediate 0.21 % and 0.1 % of the association between blood cotinine and depressive symptoms.

LIMITATION

Cross-sectional design, and lack of medication data for depression.

CONCLUSIONS

Positive association of ETS (blood cotinine) with depressive symptoms risk is partly mediated by systemic inflammation, and anti-inflammatory diet could be beneficial.

Association between secondhand smoke exposure and incident heart failure: The Multi-Ethnic Study of Atherosclerosis (MESA)

AIMS

There are no studies on the association between secondhand smoke (SHS) exposure and incident heart failure (HF). This cohort study aimed to examine the associations of self-reported and urinary cotinine-assessed SHS exposure with incident HF.

METHODS AND RESULTS

This study included 5548 non-active smoking participants aged 45-84 years and free of known cardiovascular diseases and HF at baseline who self-reported SHS exposure time in the Multi-Ethnic Study of Atherosclerosis (MESA) at baseline (2000-2002). A cohort subset of 3376 non-active smoking participants underwent urinary cotinine measurements. HF events were verified by medical records or death certificates and ascertained from baseline through 2019. Multivariable Cox proportional hazards regression analysis was used with adjustment for demographic variables, traditional cardiovascular risk factors, physical activity, tobacco pack-years and medications. During a median follow-up of 17.7 years, 353 and 196 HF events were identified in the self-report cohort and cohort subset, respectively. In the self-report cohort, compared with the SHS unexposed group (0 h/week), the highest tertile of the SHS exposed group (7-168 h/week) was not associated with incident HF (hazard ratio [HR] 0.70, 95% confidence interval [CI] 0.49-1.00; p = 0.052). In contrast, in the cohort subset, participants with detectable urinary cotinine >7.07 ng/ml had a higher risk of incident HF than those with undetectable urinary cotinine ≤7.07 ng/ml (HR 1.45, 95% CI 1.03-2.06; p = 0.034). There were no significant heterogeneities in HF risk by age, sex, race/ethnicity, or past smoking status.

CONCLUSION

Secondhand smoke exposure reflected by modestly increased urinary cotinine (>7.07 ng/ml) rather than self-report in non-active smokers was associated with a 40-50% higher risk of any HF event.

Association of secondhand smoke with fracture risk in community-dwelling nonsmoking adults in Korea

Although the detrimental effects of active smoking on bone health have been widely recognized, the impact of secondhand smoke exposure on fracture risk in non-smokers remains less understood. A total of 4843 nonsmokers aged 40-69 yr, who participated in the Korean Genome and Epidemiology Study from 2001 to 2018, were analyzed. The participants were categorized into two groups based on their exposure status to secondhand smoke: currently exposed and unexposed. The exposure group was subsequently divided into two subgroups based on the median weekly exposure time (high vs low). The incidence of new fractures was determined using self-reported questionnaires. The identified fractures were categorized according to the fracture site: overall, vertebral, hip, non-vertebral, and non-vertebral non-hip fractures. The mean age of the participants was 52.4 yr (84.1% women). Exposure to secondhand smoke was associated with an increased risk of fracture (adjusted hazard ratio [aHR]: 1.27, P = 0.028) after adjusting for multiple covariates including age, sex, BMI, household income, bone density of mid-shaft tibia, C-reactive protein, alcohol consumption, and fracture history. Secondhand smoke remained as a significant risk factor for fracture, independent of the major osteoporotic fracture probabilities estimated using a fracture risk assessment tool (aHR: 1.24, P = 0.038). The high exposure group had higher risk of fracture than that of the unexposed group (aHR: 1.33, P = 0.025), whereas the fracture risk did not differ significantly between low exposure and unexposed groups (aHR: 1.18, P = 0.253), suggesting a potential dose-response relationship. Secondhand smoke showed robust association with increased risk of non-vertebral (aHR: 1.37, P = 0.008) or non-vertebral non-hip fractures (aHR: 1.36, P = 0.013), while its association with vertebral fracture was attenuated (aHR: 1.03, P = 0.908). Secondhand smoke was associated with an elevated risk of fracture in nonsmokers, independent of clinical risk factors.

Smoking and secondhand smoke exposure and carotid intima-media thickness: Baseline data from the Aidai Cohort Study in Japan

INTRODUCTION

Epidemiological evidence regarding the relationship between smoking and secondhand smoke (SHS) exposure and carotid intima-media thickness (CIMT) has been limited in Asian populations. Employing baseline data from the Aidai Cohort Study, Japan, we evaluated the evidence in this cross-sectional study.

METHODS

Study subjects were 727 men aged 35-88 years and 1297 women aged 34-85 years. Information on smoking, SHS exposure, and confounders was obtained through a self-administered questionnaire. An automated carotid ultrasonography device was used to measure the right and left CIMT. The greatest CIMT measurement in the left or right common carotid artery was considered the maximum CIMT, and a maximum CIMT >1.0 mm was indicative of carotid wall thickening. Age, alcohol consumption, leisure time physical activity, hypertension, dyslipidemia, diabetes mellitus, body mass index, waist circumference, employment, and education level were adjusted at one time.

RESULTS

The prevalence of carotid wall thickening was 13.0%. The prevalence of never smoking was 30.5% in men and 90.1% in women. Among those who had never smoked, the prevalence of never SHS exposure at home and work was 74.3% and 48.2% in men and 38.3% and 56.3% in women, respectively. Active smoking and pack-years of smoking were independently positively related to carotid wall thickening regardless of sex, although the association with current smoking in women was not significant. Independent positive relationships were shown between former smoking and pack-years of smoking and maximum CIMT in men but not in women. No significant relationships were found between SHS exposure at home and work and carotid wall thickening or maximum CIMT in either men or women.

CONCLUSIONS

Active smoking, especially pack-years of smoking, was positively associated with carotid wall thickening in both sexes. Such positive associations with maximum CIMT were found only in men; however, interactions between smoking and sex were not significant.

Machine learning models for predicting the risk factor of carotid plaque in cardiovascular disease

Introduction

Cardiovascular disease (CVD) is a group of diseases involving the heart or blood vessels and represents a leading cause of death and disability worldwide. Carotid plaque is an important risk factor for CVD that can reflect the severity of atherosclerosis. Accordingly, developing a prediction model for carotid plaque formation is essential to assist in the early prevention and management of CVD.

Methods

In this study, eight machine learning algorithms were established, and their performance in predicting carotid plaque risk was compared. Physical examination data were collected from 4,659 patients and used for model training and validation. The eight predictive models based on machine learning algorithms were optimized using the above dataset and 10-fold cross-validation. The Shapley Additive Explanations (SHAP) tool was used to compute and visualize feature importance. Then, the performance of the models was evaluated according to the area under the receiver operating characteristic curve (AUC), feature importance, accuracy and specificity.

Results

The experimental results indicated that the XGBoost algorithm outperformed the other machine learning algorithms, with an AUC, accuracy and specificity of 0.808, 0.749 and 0.762, respectively. Moreover, age, smoke, alcohol drink and BMI were the top four predictors of carotid plaque formation. It is feasible to predict carotid plaque risk using machine learning algorithms.

Conclusions

This study indicates that our models can be applied to routine chronic disease management procedures to enable more preemptive, broad-based screening for carotid plaque and improve the prognosis of CVD patients.

Investigating the association of traditional and non-traditional tobacco product use with subclinical and clinical cardiovascular disease: The Cross-Cohort Collaboration-Tobacco working group rationale, design, and methodology

While the impact of combustible cigarette smoking on cardiovascular disease (CVD) is well-established, the longitudinal association of non-traditional tobacco products with subclinical and clinical CVD has not been fully explored due to: 1) limited data availability; and 2) the lack of well-phenotyped prospective cohorts. Therefore, there is the need for sufficiently powered well-phenotyped datasets to fully elucidate the CVD risks associated with non-cigarette tobacco products. The Cross-Cohort Collaboration (CCC)-Tobacco is a harmonized dataset of 23 prospective cohort studies predominantly in the US. A priori defined variables collected from each cohort included baseline characteristics, details of traditional and non-traditional tobacco product use, inflammatory markers, and outcomes including subclinical and clinical CVD. The definitions of the variables in each cohort were systematically evaluated by a team of two physician-scientists and a biostatistician. Herein, we describe the method of data acquisition and harmonization and the baseline sociodemographic and risk profile of participants in the combined CCC-Tobacco dataset. The total number of participants in the pooled cohort is 322782 (mean age: 59.7 ± 11.8 years) of which 76% are women. White individuals make up the majority (73.1%), although there is good representation of other race and ethnicity groups including African American (15.6%) and Hispanic/Latino individuals (6.4%). The prevalence of participants who never smoked, formerly smoked, and currently smoke combustible cigarettes is 50%, 36%, and 14%, respectively. The prevalence of current and former cigar, pipe, and smokeless tobacco is 7.3%, 6.4%, and 8.6%, respectively. E-cigarette use was measured only in follow-up visits of select studies, totaling 1704 former and current users. CCC-Tobacco is a large, pooled cohort dataset that is uniquely designed with increased power to expand knowledge regarding the association of traditional and non-traditional tobacco use with subclinical and clinical CVD, with extension to understudied groups including women and individuals from underrepresented racial-ethnic groups.

Nicotine dependence and visceral adiposity as risk factors for the development and severity of carotid artery stenosis

Nicotine dependence (ND) and visceral adiposity are emerging as independent risk factors for cardiovascular diseases, including carotid artery stenosis (CAS). This study aimed to determine the relationship between ND and the contribution of abdominal fat to the onset of CAS, which is indicated by a luminal narrowing of at least 60% as determined by duplex and/or Doppler ultrasound. We prospectively collected data from 60 patients with CAS and 60 age- and gender-matched healthy subjects. The Fagerström Test for Nicotine Dependence (FTND), a common research tool, was used in the study. The original questionnaire was designed to gather social and demographic data. Anthropometric measurements, visceral adiposity index (VAI), and lipid accumulation products (LAP) were used to assess obesity. Most patients showed a high or mild-moderate degree of ND: 46.67% and 35%, respectively. The median visceral adiposity index (VAI) and lipid accumulation product (LAP) in patients was 3.92 and 32.83, respectively. Prolonged smoking duration, increased intensity, and high ND are hallmarks of CAS patients.

Passive Smoking Exposure Modifies Cardiovascular Structure and Function: Beijing Child Growth and Health Cohort (PROC) Study

Passive smoking exposure in children is prevalent worldwide and exposes children to respiratory and systemic toxins. In this study, we enrolled 568 children to study how secondhand smoke (SHS) might affect children's cardiovascular health in China. The measurement of nicotine and its metabolites in urine showed that 78.9% of children were exposed to SHS. Children exposed to SHS had greater interventricular septum thickness (p = 0.005) and left ventricular mass index (p = 0.008) than nonexposed children. Urinary norcotinine levels were associated with increased ascending aorta diameter (β = 0.10, 95%CI 0.02-0.17) and decreased left ventricular end systolic diameter (β = -0.10, 95%CI -0.19 to -0.01). The effects of SHS exposure on cardiovascular function: norcotinine levels associated with lower left ventricular mass index (β = -0.32, 95%CI -0.59 to -0.05), left ventricular end diastolic volume index (β = -0.43, 95%CI -0.85 to -0.02), and left ventricular end systolic volume index (β = -0.20, 95%CI -0.37 to -0.03). Moreover, there no no significant associations of nicotine, cotinine, and trans-3'-hydroxycotinine with cardiovascular health. Overall, SHS exposure in children remains prevalent in Beijing and may affect children's cardiovascular development, in both structure and function. It suggests that stricter and practical measures are needed toward the elimination of tobacco use in children's environments.

Secondhand tobacco smoke exposure, urine cotinine, and risk of incident atrial fibrillation: The multi-ethnic study of atherosclerosis

BACKGROUND

Secondhand tobacco smoke (SHS) exposure may reduce heart rate variability and lead to atrial fibrillation (AF); however prior study findings have not been confirmed using objective measures for both SHS and AF events.

METHODS

We prospectively examined the association between SHS exposure and incident AF in 5731 participants, ages of 45-84 years and free of known AF and other cardiovascular diseases (CVD) at baseline (2000-2002), who were followed through 2015 in the Multi-Ethnic Study of Atherosclerosis (MESA). SHS weekly exposure time was identified by self-report. Urine cotinine was collected in a cohort subset of 3237 current non-smoking cohort participants. AF events were identified using Medicare claims, hospital records, and 12‑lead electrocardiographic findings. A multivariable Cox proportional hazards regression analysis was used with simultaneous adjustment for demographic factors, educational level, health insurance status, active smoking status, tobacco pack-years, traditional CVD risk factors, depressive symptoms and medications.

RESULTS

During a median follow-up of 14.0 years, 856 and 452 AF events were identified in the overall and the cohort subset, respectively. No association of SHS exposure time or urine cotinine with incident AF was observed. However, a higher AF risk with greater urine cotinine (8.53-442.0 ng/mL) compared with lower urine cotinine (≤7.07 ng/mL) was observed in never smokers [hazard ratios (HR) and 95% confidence intervals: 1.60 (1.16, 2.19)], but not in former smokers [HR: 0.88 (0.63, 1.23)] (p-value for multiplicative interaction: 0.009 and for additive interaction: 0.017, respectively).

CONCLUSION

Objectively measured greater SHS exposure expressed by urine cotinine might be associated with 1.6-fold higher risk of incident AF in never smokers.

Inflammatory markers and lung function in relation to indoor and ambient air pollution

Ambient air pollution causes a range of adverse health effects, whereas effects of indoor sources of air pollution are not well described in high-income countries. We compared hazards of ambient air pollution and indoor sources with respect to important biomarkers of cardiorespiratory effects in terms of lung function and systemic inflammation in a middle-aged Danish cohort. Our cohort comprised 5199 men and women aged 49-63 years at the recruitment during April 2009 to March 2011, with information on exposure to second-hand smoke (SHS) and use of candles, wood stove, kerosene heater and gas cooker as well as relevant covariates. Ambient air pollution exposure was assessed as 2-year mean nitrogen dioxide (NO₂) at the address (mean ± SD: 17.1 ± 9.9 μg/m³) and 4-day average levels of particulate matter with diameter <2.5 μm (PM_2.5; mean ± SD: 12.5 ± 6.0 μg/m³) in urban background. Lung function was assessed as % predicted forced expiratory volume in the first second (FEV1) and inflammatory markers comprised interleukin-6 (IL-6), IL-10, IL-18, interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), and high sensitivity C-reactive protein (hs-CRP). We used random-effect regression models controlling for potential confounders as well as models with further adjustment for self-reported health or for all other exposures. In models adjusted for confounders FEV1 was inversely associated with exposure to NO₂, (-0,83% per 10 μg/m³; 95% CI: -1.26; -0.41%), SHS (-0.56% per 1 of 5 categories increment; 95% CI: -0.89; -0.23%), and gas cooker without hood (-0.89%; 95% CI: -1.62; -0.17%), whereas use of wood stove and candles showed positive associations, although these attenuated by mutual adjustment for all exposures or self-reported health. IL-6 showed positive associations with NO₂ (6.30% increase in log-transformed values per 10 μg/m³; 95% CI: 3.54; 9.05%), PM_2.5 (7.82% per 10 μg/m³; 95% CI: 3.35; 12.4%), SHS (4.38% per increase of 1 of 5 categories; 95% CI: 2.22; 6.54%) and use of kerosene (13.8%; 95% CI: 2.51; 25.1%), whereas the associations with use of wood stove and candles were inverse. PM_2.5 and NO₂ showed positive associations with IFN-γ and TNF-α, while PM_2.5 further associated with IL-10 and IL-18. Hs-CRP was inversely associated with use of candles. These results suggest that the levels of exposure to ambient air pollution and SHS are more harmful than are the levels of exposure to indoor combustion sources from candles and wood stoves in a high-income setting.

Association between secondhand smoke and peripheral arterial disease: a meta-analysis of cross-sectional studies

PURPOSE

The association between secondhand smoke (SHS) and peripheral arterial disease (PAD) was inconsistent and the studies were relatively scarce, hence, we conducted a meta-analysis of the association between SHS and PAD.

MATERIALS AND METHODS

We systematically searched three electronic databases (PubMed, EMBASE, and Web of Science), and calculated the pooled prevalence risk ratio (RR) and estimated standard error by random effect model from the meta-analysis. Furthermore, we performed a subgroup meta-analysis according to the location of SHS exposure.

RESULTS

We initially identified 502 articles from the electronic database, and 6 articles, cross-sectional data from 4 cross-sectional studies and 2 prospective cohort studies, were included in the meta-analysis. Among these six articles, two studies showed a significant correlation between SHS exposure and PAD, whereas no study showed a negative correlation between SHS exposure and PAD. In the meta-analysis, pooled prevalence showed a significant association between SHS exposure and PAD (RR = 1.23; 95% confidence interval [CI] 1.08-1.41; z = 3.02, p = 0.003). In the subgroup analysis based on location of SHS exposure, the prevalence RR of PAD at home was 1.30 (95% CI 1.14-1.49, Z-3.99, p < 0.0001). The prevalence RR in the subgroup of SHS exposure at work was not significant (RR = 0.89; 95% CI 0.55-1.44; z = 0.48, p = 0.63).

CONCLUSION

Exposure to SHS was significantly and positively associated with PAD. Moreover, we found a significant association between exposure to SHS and PAD at home, but the association was not significant at work.

Subclinical cardiovascular disease and utility of coronary artery calcium score

ASCVD are the leading causes of mortality and morbidity among Globe. Evaluation of patients' comprehensive and personalized risk provides risk management strategies and preventive interventions to achieve gain for patients. Framingham Risk Score (FRS) and Systemic Coronary Risk Evaluation Score (SCORE) are two well studied risk scoring models, however, can miss some (20-35%) of future cardiovascular events. To obtain more accurate risk assessment recalibrating risk models through utilizing novel risk markers have been studied in last 3 decades and both ESC and AHA recommends assessing Family History, hs-CRP, CACS, ABI, and CIMT. Subclinical Cardiovascular Disease (SCVD) has been conceptually developed for investigating gradually progressing asymptomatic development of atherosclerosis and among these novel risk markers it has been well established by literature that CACS having highest improvement in risk assessment. This review study mainly selectively discussing studies with CACS measurement. A CACS = 0 can down-stratify risk of patients otherwise treated or treatment eligible before test and can reduce unnecessary interventions and cost, whereas CACS ≥ 100 is equivalent to statin treatment threshold of ≥ 7.5% risk level otherwise statin ineligible before test. Since inflammation, insulin resistance, oxidative stress, dyslipidemia and ongoing endothelial damage due to hypertension could lead to CAC, ASCVD linked with comorbidities. Recent cohort studies have shown a CACS 100-300 as a sign of increased cancer risk. Physical activity, dietary factors, cigarette use, alcohol consumption, metabolic health, family history of CHD, aging, exposures of neighborhood environment and non-cardiovascular comorbidities can determine CACs changes.

Smoking and the Pathophysiology of Peripheral Artery Disease

Smoking is one of the most important preventable factors causing peripheral artery disease (PAD). The purpose of this review is to comprehensively analyze and summarize the pathogenesis and clinical characteristics of smoking in PAD based on existing clinical, in vivo, and in vitro studies. Extensive searches and literature reviews have shown that a large amount of data exists on the pathological process underlying the effects of cigarette smoke and its components on PAD through various mechanisms. Cigarette smoke extracts (CSE) induce endothelial cell dysfunction, smooth muscle cell remodeling and macrophage phenotypic transformation through multiple molecular mechanisms. These pathological changes are the molecular basis for the occurrence and development of peripheral vascular diseases. With few discussions on the topic, we will summarize recent insights into the effect of smoking on regulating PAD through multiple pathways and its possible pathogenic mechanism.

Particulate matter air pollutants and cardiovascular disease: Strategies for intervention

Air pollution is consistently linked with elevations in cardiovascular disease (CVD) and CVD-related mortality. Particulate matter (PM) is a critical factor in air pollution-associated CVD. PM forms in the air during the combustion of fuels as solid particles and liquid droplets and the sources of airborne PM range from dust and dirt to soot and smoke. The health impacts of PM inhalation are well documented. In the US, where CVD is already the leading cause of death, it is estimated that PM2.5 (PM < 2.5 μm in size) is responsible for nearly 200,000 premature deaths annually. Despite the public health data, definitive mechanisms underlying PM-associated CVD are elusive. However, evidence to-date implicates mechanisms involving oxidative stress, inflammation, metabolic dysfunction and dyslipidemia, contributing to vascular dysfunction and atherosclerosis, along with autonomic dysfunction and hypertension. For the benefit of susceptible individuals and individuals who live in areas where PM levels exceed the National Ambient Air Quality Standard, interventional strategies for mitigating PM-associated CVD are necessary. This review will highlight current state of knowledge with respect to mechanisms for PM-dependent CVD. Based upon these mechanisms, strategies for intervention will be outlined. Citing data from animal models and human subjects, these highlighted strategies include: 1) antioxidants, such as vitamins E and C, carnosine, sulforaphane and resveratrol, to reduce oxidative stress and systemic inflammation; 2) omega-3 fatty acids, to inhibit inflammation and autonomic dysfunction; 3) statins, to decrease cholesterol accumulation and inflammation; 4) melatonin, to regulate the immune-pineal axis and 5) metformin, to address PM-associated metabolic dysfunction. Each of these will be discussed with respect to its potential role in limiting PM-associated CVD.

Second-Hand Smoke and Its Synergistic Effect with a Body-Mass Index of >24.9 kg/m2 Increase the Risk of Gout Arthritis in Indonesia

To analyze the association between smoking status (active smoking and exposure to Second-Hand Smoking (SHS)) and the synergistic effect of smoking status and BMI with gout risk, a community-based case-control design was undertaken among 385 participants, including 304 healthy controls and 81 gout patients from seven community health services. Adjusted Odd Ratios (AORs) and 95% Confidence Interval (CIs) of gout for active smoking and SHS were 3.26 (95% CI = 1.07~9.90) and 4.67 (95% CI = 2.18~10.00) compared to non-smokers. Time-dependent manner of active smoking and SHS significantly increased gout risk with AORs and 95% CIs of 5.95 (1.41~25.03) and 10.12 (3.51~29.14). Dose-dependency of active smokers and SHS showed AORs and 95% CIs of 5.15 (1.28~20.63) and 4.37 (1.33~14.28). Smoking 20 cigarettes (one pack) per day for one year is equivalent to one pack-year. Active smoking >20 pack-year and SHS > 26.5 pack-year increased gout risk with AORs and 95% CIs of 7.18 (1.53~33.67) and 9.95 (3.64~27.22). Participants who smoked (active smoking and SHS) and with Body Mass Index (BMI) of > 24.9 kg/m2 synergistically increased gout risk, with an AOR of 9.65 and 95% CI of 3.25~28.65, compared to BMI ≤ 24.9 kg/m2 and non-smoker. Smoking status (active smoking and SHS) and the synergistic effect of smoking status and BMI increased gout risk in Indonesia.

Association of a Tobacco-specific Nitrosamine Carcinogen with Urinary Cotinine, Urinary Sodium Excretion, and Total Energy Intake in Adolescents and Children

This study investigated the association of a tobacco-specific nitrosamine carcinogen, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanol (NNAL) with urinary cotinine (uCot), urinary sodium (uNa) excretion, systolic blood pressure (sBP), and total energy intake in adolescents and children in relation to the subjects' age. A total of 790 subjects aged 6-19 years were evaluated. NNAL, uCot, corrected NNAL (cNNAL), the NNAL/uCot ratio, uNa, sBP, and nutrient intake were measured. A strong association between uCot and cNNAL was observed in children who were 11 years of age (r=0.881, P<0.001); however, no significant association was noted in adolescents who were 19 years of age. The uNa level was significantly higher (133.9 mmol/L vs. 107.8 mmol/L, P<0.001) and sBP was significantly lower (105.3 mmHg vs. 110.6 mmHg, P=0.012) in adolescents with elevated NNAL than in those without elevated NNAL. NNAL was significantly higher in subjects with increased uNa excretion than in those without increased uNa excretion. NNAL was positively correlated with uNa (r=0.183, P<0.001) and negatively correlated with sBP (r=-0.142, P<0.001). Non-smokers with elevated NNAL/uCot ratios had significantly lower total energy intake than those without elevated NNAL/uCot ratios (1729.0 kcal/day vs. 1911.0 kcal/day, P=0.008). The relationship between NNAL and uCot varied according to the subjects' age. NNAL seems to play a role in decreasing sBP by enhancing uNa excretion. Insufficient nutrient intake may contribute to endogenous formation of NNAL in non-smoking adolescents and children.

Subnational exposure to secondhand smoke in Iran from 1990 to 2013: a systematic review

Every year, almost eight million people die from tobacco-related diseases, among which around 1.2 million die from secondhand smoke (SHS) exposure. Generally, it is estimated that SHS constituents generated in the interval between puffs are approximately 3 times more toxic than those produced at the moment of puffing. There is no risk-free level of SHS exposure, and even brief exposure can be harmful to health. The aim of this study was to assess SHS exposure and its trend in the different provinces of Iran from 1990 to 2013. To collect available data on SHS exposure, a systematic review was performed. We searched international and national databases using a combination of Medical Subject Headings (MeSH) and relevant text words in the titles, abstracts, and/or keywords. Also, the data in national surveys were gathered. The frequency of exposure in different provinces as well as age, sex, and rural/urban areas were extracted. Afterwards, modeling was done to estimate SHS exposure from the smoking data. According to our findings, SHS exposure was more prevalent among young people. Moreover, this exposure was greater in rural areas as compared to urban areas. A national study on 13-15-year-old individuals showed the highest exposure occurred outdoors. In addition, a declining trend was observed on SHS exposure over time. It seems that attention to the importance of SHS exposure in researches in Iran dates back to 2001, and gradually, especially in recent years, further studies have been conducted on SHS exposure.

Second-Hand Smoke Exposure Among Coronary Heart Disease Patients

Purpose

The objectives of this study were to assess second-hand smoke (SHS) exposure among coronary heart disease (CHD) patients at home, in transportation, workplace, public and social places; to examine the demographic factors that predict SHS exposure; and to investigate the relationship between SHS exposure and CHD complications, age at the time of diagnosis, and number of admissions in the last year.

Patients and Methods

A descriptive cross-sectional design was used with a convenient sample of 400 CHD patients from three hospitals in Jordan. A modified version of the Smoking Scale for Adults (SS-A) was used.

Results

The percentage of SHS exposure was 64% in public places, 51.5% in social places, 48.5% in the household, 31% in transportation, while it was only 14.8% in the workplace. In addition, being male, employed, having a younger age and lower education significantly predicted higher exposure to SHS. Exposure to SHS was positively associated with CHD complications and the number of admissions, while it was negatively associated with the age at diagnosis with CHD.

Conclusion

Collaboration is needed among all health care sectors to adopt educational strategies about SHS exposure and to activate policies to prohibit smoking in public places.

Rice Intake, Arsenic Exposure, and Subclinical Cardiovascular Disease Among US Adults in MESA

Background Arsenic-related cardiovascular effects at exposure levels below the US Environmental Protection Agency's standard of 10 μg/L are unclear. For these populations, food, especially rice, is a major source of exposure. We investigated associations of rice intake, a marker of arsenic exposure, with subclinical cardiovascular disease (CVD) markers in a multiethnic population. Methods and Results Between 2000 and 2002, MESA (Multi-Ethnic Study of Atherosclerosis) enrolled 6814 adults without clinical CVD. We included 5050 participants with baseline data on rice intake and markers of 3 CVD domains: inflammation (hsCRP [high-sensitivity C-reactive protein], interleukin-6, and fibrinogen), vascular function (aortic distensibility, carotid distensibility, and brachial flow-mediated dilation), and subclinical atherosclerosis at 3 vascular sites (carotid intima-media thickness, coronary artery calcification, and ankle-brachial index). We also evaluated endothelial-related biomarkers previously associated with arsenic. Rice intake was assessed by food frequency questionnaire. Urinary arsenic was measured in 310 participants. A total of 13% of participants consumed ≥1 serving of rice/day. Compared with individuals consuming <1 serving of rice/week, ≥1 serving of rice/day was not associated with subclinical markers after demographic, lifestyle, and CVD risk factor adjustment (eg, geometric mean ratio [95% CI] for hsCRP, 0.98 [0.86-1.11]; aortic distensibility, 0.99 [0.91-1.07]; and carotid intima-media thickness, 0.98 [0.91-1.06]). Associations with urinary arsenic were similar to those for rice intake. Conclusions Rice intake was not associated with subclinical CVD markers in a multiethnic US population. Research using urinary arsenic is needed to assess potential CVD effects of low-level arsenic exposure. Understanding the role of low-level arsenic as it relates to subclinical CVD may contribute to CVD prevention and control.

Associations of cigarette smoking and burden of thoracic aortic calcification in asymptomatic individuals: A dose-response relationship

Smoking is known as a powerful predictor of pathological coronary atherosclerosis. Thoracic aortic calcification (TAC), an alternative marker for pathological atherosclerosis, has also been shown to be associated unfavorable cardiovascular outcomes. We aimed to investigate the dose-response relationship between cigarette use and calcification burden in subjects free from clinical symptoms. Among 3109 patients enrolled in this analysis, we categorized study participants according to smoking exposure pattern as: non-smokers, ex-smokers and current smokers. Smoking dose (cigarette/day), duration (years) and pack-years were semi-quantified as smoking dose exposure variables. Thoracic aortic calcification burden (including TAC score, plaque volume and plaque density) were determined and related to smoking dose and pattern information. TAC burdens (including TAC score, plaque volume and density) were highest in current smoker compared to non-smoker group, with ex-smoker showing TAC burdens in-between (all ANOVA p<0.05). Linear regression models consistently demonstrated that TAC burdens as continuous variables were independently higher in a dose-dependent manner with smoking exposure, particularly in high-dose (> 10 cigarettes/day) and the long-duration (> 3 years) smokers, even after adjusting for baseline demographic differences (all p<0.05). By logistic regression, subjects who never smoke consistently demonstrated reduced risk of TAC existence (adjusted OR: 0.65 [95% CI: 0.48–0.86], P = 0.003) in contrary to those current smokers (adjusted OR: 1.47 [95% CI: 1.10–1.89], P = 0.009). A dose-response relationship between active cigarette use and TAC burden was observed, with those who never exposed to smoking or quitted demonstrating partial protective effects. Our data provided imaging-based evidence about the potential deleterious biological hazards of long-term and high-dose cigarette consumption.

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.

The Burden of Modifiable Risk Factors in Newly Defined Categories of Blood Pressure

BACKGROUND

The 2017 American College of Cardiology/American Heart Association Guideline introduced new categories of high blood pressure. The vast majority of individuals in these newly defined categories are recommended for nonpharmacological intervention rather than antihypertensive therapy. This study sought to determine the burden of potentially modifiable risk factors of hypertension among untreated adults in the newly defined categories of blood pressure.

METHODS

We analyzed data from the 1999-2014 National Health and Nutrition Examination Survey (N = 37,448). Potentially modifiable risk factors included abdominal obesity, high non-high-density lipoprotein (HDL) cholesterol, secondhand smoking, binge drinking, suboptimal physical activity, and low-fiber diet.

RESULTS

Although the prevalence of certain modifiable risk factors decreased during the study period, the prevalence of low fiber intake, suboptimal physical activity, abdominal obesity, and binge drinking remained high during the last combined survey cycle (2011-2014). Modifiable risk factors generally demonstrated dose-response relationships with high blood pressure categories. The most common type of risk factor clustering included low fiber intake, suboptimal physical activity, high non-HDL cholesterol, and abdominal obesity, with its prevalence increasing gradually from 9.5% (95% confidence interval, 8.8%-10.3%) in the normal blood pressure group to 16.5% (95% confidence interval, 14.8%-18.3%) in the stage 2 hypertension group (P_trend < .001). The prevalence of 4 or more modifiable risk factors per participant increased stepwise, ranging from 28.5% in the normal blood pressure group to 48.0% in the stage 2 hypertension group (P_trend < .001).

CONCLUSIONS

The burden of potentially modifiable risk factors for hypertension shows progressive increase along the blood pressure categories and represents an important target for nonpharmacologic intervention.

Associations of Cigarette Smoking With Subclinical Inflammation and Atherosclerosis: ELSA-Brasil (The Brazilian Longitudinal Study of Adult Health)

Background

There is a need to identify sensitive biomarkers of early tobacco‐related cardiovascular disease. We examined the association of smoking status, burden, time since quitting, and intensity, with markers of inflammation and subclinical atherosclerosis.

Methods and Results

We studied 14 103 participants without clinical cardiovascular disease in ELSA‐Brasil (Brazilian Longitudinal Study of Adult Health). We evaluated baseline cross‐sectional associations between smoking parameters and inflammation (high‐sensitivity C‐reactive protein [hsCRP]) and measures of subclinical atherosclerosis (carotid intima–media thickness, ankle‐brachial index, and coronary artery calcium [CAC]). The cohort included 1844 current smokers, 4121 former smokers, and 8138 never smokers. Mean age was 51.7±8.9 years; 44.8% were male. After multivariable adjustment, compared with never smokers, current smokers had significantly higher levels of hsCRP (β=0.24, 0.19–0.29 mg/L; P<0.001) and carotid intima–media thickness (β=0.03, 0.02–0.04 mm; P<0.001) and odds of ankle‐brachial index ≤1.0 (odds ratio: 2.52; 95% confidence interval, 2.06–3.08; P<0.001) and CAC >0 (odds ratio: 1.83; 95% confidence interval, 1.46–2.30; P<0.001). Among former and current smokers, pack‐years of smoking (burden) were significantly associated with hsCRP (P<0.001 and P=0.006, respectively) and CAC (P<0.001 and P=0.002, respectively). Among former smokers, hsCRP and carotid intima–media thickness levels and odds of ankle‐brachial index ≤1.0 and CAC >0 were lower with increasing time since quitting (P<0.01). Among current smokers, number of cigarettes per day (intensity) was positively associated with hsCRP (P<0.001) and CAC >0 (P=0.03) after adjusting for duration of smoking.

Conclusions

Strong associations were observed between smoking status, burden, and intensity with inflammation (hsCRP) and subclinical atherosclerosis (carotid intima–media thickness, ankle‐brachial index, CAC). These markers of early cardiovascular disease injury may be used for the further study and regulation of traditional and novel tobacco products.

The relationship between smoking intensity and subclinical cardiovascular injury: The Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND AND AIMS

Modern tobacco regulatory science requires an understanding of which biomarkers of cardiovascular injury are most sensitive to cigarette smoking exposure.

METHODS

We studied self-reported current smokers from the Multi-Ethnic Study of Atherosclerosis. Smoking intensity was defined by number of cigarettes/day and urinary cotinine levels. Subclinical cardiovascular injury was assessed using markers of inflammation [high-sensitivity C-reactive protein (hsCRP), interleukin 6 & 2 (IL-2 & IL-6), tumor necrosis factor alpha (TNF-α)], thrombosis (fibrinogen, D-dimer, homocysteine), myocardial injury (troponin T; TnT), endothelial damage (albumin: creatinine ratio), and vascular function [aortic & carotid distensibility, flow-mediated dilation (FMD)]. Biomarkers were modeled as absolute and percent change using multivariable-adjusted linear regression models adjusted for cardiovascular risk factors and smoking duration.

RESULTS

Among 843 current smokers, mean age was 58 (9) years, 53% were men, 39% were African American, mean number of cigarettes per day was 13 (10), and median smoking duration was 39 (15) years. Cigarette count was significantly associated with higher hsCRP, IL-6 and fibrinogen (β coefficients: 0.013, 0.011, 0.60 respectively), while ln-transformed cotinine was associated with the same biomarkers (β coefficients: 0.12, 0.04, 5.3 respectively) and inversely associated with aortic distensibility (β coefficient: -0.13). There was a limited association between smoking intensity and homocysteine, D-dimer, and albumin:creatinine ratio in partially adjusted models only, while there was no association with IL-2, TNF-α, carotid distensibility, FMD, or TnT in any model. In percent change analyses, relationships were strongest with hsCRP.

CONCLUSIONS

Smoking intensity was associated with early biomarkers of CVD, particularly, markers of systemic inflammation. Of these, hsCRP may be the most sensitive.

Water pipe (Shisha, Hookah, Arghile) Smoking and Secondhand Tobacco Smoke Effects on CYP1A2 and CYP2A6 Phenotypes as Measured by Caffeine Urine Test

Public policies to stop or reduce cigarette smoking and exposure to secondhand smoke and associated diseases have yielded successful results over the past decade. Yet, the growing worldwide popularity of another form of tobacco consumption, water pipe smoking, has received relatively less attention. To the best of our knowledge, no study to date has evaluated the effects of water pipe smoking on cytochrome P450 (CYP450) activities and drug interaction potential in humans, whereas only limited information is available on the impact of secondhand smoke on drug metabolism. In a sample of 99 healthy volunteers (28 water pipe smokers, 30 secondhand tobacco smoke exposed persons, and 41 controls), we systematically compared CYP1A2 and CYP2A6 enzyme activities in vivo using caffeine urine test. The median self-reported duration of water pipe smoking was 7.5 h/week and 3 years of exposure in total. The secondhand smoke group had a median of 14 h of self-reported weekly exposure to tobacco smoke indoor where a minimum of five cigarettes were smoked/hour for a total of 3.5 years (median). Analysis of variance did not find a significant difference in CYP1A2 and CYP2A6 activities among the three study groups (p > 0.05). Nor was there a significant association between the extent of water pipe or secondhand smoke exposure and the CYP1A2 and CYP2A6 activities (p > 0.05). Further analysis in a subsample with smoke exposure more than the median values also did not reveal a significant difference from the controls. Although we do not rule out an appreciable possible impact of water pipe smoke and secondhand smoke on in vivo activities of these two drug metabolism pathways, variability in smoke constituents from different tobacco consumption methods (e.g., water pipe) might affect drug metabolism in ways that might differ from that of cigarette smoke. Further studies in larger prospective samples are recommended to evaluate water pipe and secondhand tobacco smoke effects on CYP450 function, particularly at higher smoke exposure conditions.