Hemodynamic and vascular effects of active and passive smoking

Inhaled turmerone can attenuate nicotine-induced degeneration of the aorta

Nicotine in secondhand smoke can increase the risk of development of cardiovascular disease in passive smokers through degeneration of the aorta which is one of main pathologies of cardiovascular disease. We speculated that the adverse effect of nicotine can be attenuated by volatile active molecules. As the potential molecule having vasoprotective effect, we focused on turmerone which is major volatile compound in turmeric (Curcuma longa). Oral administration of turmerone reportedly shows biological activities such as anti-inflammation, anti-oxidation, and anti-depression effects. We previously reported that turmerone was detected in the blood and organs of mice that inhaled turmeric essential oil. In addition, high fat-induced weight gain was suppressed in the group of mice that inhaled turmeric essential oil, suggesting the existence of biological activity of inhaled turmerone. However, the effects of inhaled turmerone on the aorta remain unclear. The aim of this study is to investigate the effects of inhaled turmerone on nicotine-induced aortic degeneration. Nicotine-induced degradation of elastic fiber and increased matrix metalloproteinase (MMP)-2 was attenuated by inhalation of the turmeric essential oil. In the serum of mice that inhaled the turmeric essential oil, all turmerone species, α-turmerone, β-turmerone, and ar-turmerone, were detected. In ex vivo cultured aorta, ar-turmerone showed the strongest protective effects on nicotine-induced degeneration of the aorta compared to α-turmerone and β-turmerone. These data indicate that inhaled turmerone attenuate nicotine-induced aortic degeneration after incorporated into the body.

Genetic and Phenotypic Profiling of Triptan Users in a Swedish Cluster Headache Cohort

Up to 25% of individuals who live with cluster headache (CH), an extremely painful primary headache disorder, do not adequately respond to the first-line treatment, triptans. Studies have indicated that genetic variants can play a role in treatment response. Likewise, differences in clinical characteristics can give clues to mechanisms underlying triptan non-response. Our aim was to investigate five genetic variants previously implicated in triptan response and their relation to triptan usage in our Swedish CH cohort and to investigate potential distinctions in clinical characteristics. 545 CH patients were screened for the genetic variants rs1024905, rs6724624, rs4795541, rs5443, and rs2651899 with a case control design based on triptan usage. Analysis of clinical characteristics was based on self-reported questionnaire data from 893 patients. One genetic variant, rs1024905, was significantly associated with triptan non-usage in CH (Pc = 0.010). In addition, multi-allele effector analysis showed that individuals with a higher number of effector variants were less likely to use triptans (P = 0.007). Analysis of clinical characteristics showed that triptan users were more likely to have alcohol as a trigger (57.4% vs 43.4%, P = 0.002), have autonomic symptoms (95.1% vs 88.1%, P = 0.002), and be current smokers (27.0% vs 21.9%, P = 0.033) compared to non-users. These results support the hypothesis that genetic variants can play a role in triptan usage in CH and that patients with a typical CH phenotype are more likely to use triptans.

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.

Evaluation of neural reflex activation as a potential mode of action for respiratory and cardiovascular effects of fine particulate matter

OBJECTIVES

Mortality from respiratory and cardiovascular health conditions contributes largely to the total mortality that has been associated with exposure to PM2.5 in epidemiology studies. A mode of action (MoA) for these underlying morbidities has not been established, but it has been proposed that some effects of PM2.5 occur through activation of neural reflexes.

MATERIALS AND METHODS

We critically reviewed the experimental studies of PM2.5 (including ambient PM2.5, diesel exhaust particles, concentrated ambient particles, diesel exhaust, and cigarette smoke) and neural reflex activation, and applied the principles of the International Programme on Chemical Safety (IPCS) MoA/human relevance framework to assess whether they support a biologically plausible and human-relevant MoA by which PM2.5 could contribute to cardiovascular and respiratory causes of death. We also considered whether the evidence from these studies supports a non-threshold MoA that operates at low, human-relevant PM2.5 exposure concentrations.

RESULTS AND DISCUSSION

We found that the proposed MoA of neural reflex activation is biologically plausible for PM2.5-induced respiratory effects at high exposure levels used in experimental studies, but further studies are needed to fill important data gaps regarding the relevance of this MoA to humans at lower PM2.5 exposure levels. A role for the proposed MoA in PM2.5-induced cardiovascular effects is plausible for some effects but not others.

CONCLUSIONS

Further studies are needed to determine whether neural reflex activation is the MoA by which PM2.5 could cause either respiratory or cardiovascular morbidities in humans, particularly at the ambient concentrations associated with total mortality in epidemiology studies.

Transverse Cervical Artery for Head and Neck Reconstruction with Free Jejunal Flaps: A Retrospective Study of Computed Tomography Angiography

BACKGROUND

 The transverse cervical artery is less commonly used than other external carotid arteries as a recipient vessel. Therefore, we aimed to compare the utility of the transverse cervical artery as a recipient vessel with that of the external carotid artery system for microvascular head and neck reconstruction by quantitative analysis of dynamic-enhanced computed tomography.

METHODS

 Fifty-one consecutive patients who underwent free jejunum transfer following total pharyngolaryngectomy between January 2017 and December 2020 were retrospectively reviewed. Ninety-four pairs of the diameters of the transverse cervical artery, superior thyroid artery, and lingual artery, measured via computed tomography angiography, were analyzed. Operative outcomes were compared between the following groups based on the recipient artery: transverse cervical artery (n = 27), superior thyroid artery (n = 17), and other artery (n = 7) groups.

RESULTS

 In the analysis of the computed tomography angiography, nine transverse cervical arteries (9.6%) could not be identified. However, the percentage was significantly lower than the percentage of superior thyroid arteries (20.2%) and lingual arteries (18.1%) (p < 0.01). Among the identified vessels, the transverse cervical arteries (2.09 ± 0.41 mm) and the lingual arteries (1.97 ± 0.40 mm) were significantly larger than the superior thyroid arteries (1.70 ± 0.36 mm) in diameter at the commonly used level (p < 0.01). Multivariate analysis revealed that prior radiation therapy was not an independent factor significantly affecting transverse cervical artery diameter (p = 0.17). Intraoperative anastomotic revision was required in only two cases of the superior thyroid artery.

CONCLUSION

 The transverse cervical artery can offer a larger caliber and more reliable candidate than the superior thyroid artery for a recipient artery. More liberal use of the transverse cervical artery may improve the safety of microsurgical head and neck reconstruction.

Knowledge, Awareness, and Determinants of Medication Adherence in Hypertensive Patients: A Hospital-Based Cross-sectional Study in North India

Background

Knowledge and awareness studies reveal the basic information of the community and the misconceptions in relation to practices of a disease. The identification of such factors is important as they directly influence the health care-related interventions. Hypertension is one of the emerging noncommunicable diseases (NCDs) globally. So, we conducted this study to assess the status of our community regarding hypertension.

Materials and Methods

The study was conducted on 300 hypertensive patients to assess the knowledge and awareness by a hypertension fact questionnaire. Medication adherence was assessed in the same group of patients by Hill-Bone scale-a uniform scale used worldwide.

Results

Our study revealed a greater number of females with hypertension as compared to males and a maximum number of patients being in the age-group of 61-70 years and belonging to rural areas. Most of the patients had a secondary education as a highest educational qualification with only 10% of patients being postgraduates. A fair number of patients had a good knowledge and awareness about their disease, and most of the respondents accounted forgetfulness as a main reason for nonadherence to therapy over other reasons.

Conclusion

Our population has good knowledge and awareness about their disease despite not having very good educational qualifications, and we need to strengthen our healthcare programs for even more greater dissemination of information.

Nicotine and Cardiovascular Health: When Poison is Addictive - a WHF Policy Brief

Nicotine is universally recognized as the primary addictive substance fuelling the continued use of tobacco products, which are responsible for over 8 million deaths annually. In recent years, the popularity of newer recreational nicotine products has surged drastically in many countries, raising health and safety concerns. For decades, the tobacco industry has promoted the myth that nicotine is as harmless as caffeine. Nonetheless, evidence shows that nicotine is far from innocuous, even on its own. In fact, numerous studies have demonstrated that nicotine can harm multiple organs, including the respiratory and cardiovascular systems. Tobacco and recreational nicotine products are commercialized in various types and forms, delivering varying levels of nicotine along with other toxic compounds. These products deliver nicotine in profiles that can initiate and perpetuate addiction, especially in young populations. Notably, some electronic nicotine delivery systems (ENDS) and heated tobacco products (HTP) can deliver concentrations of nicotine that are comparable to those of traditional cigarettes. Despite being regularly advertised as such, ENDS and HTP have demonstrated limited effectiveness as tobacco cessation aids in real-world settings. Furthermore, ENDS have also been associated with an increased risk of cardiovascular disease. In contrast, nicotine replacement therapies (NRT) are proven to be safe and effective medications for tobacco cessation. NRTs are designed to release nicotine in a slow and controlled manner, thereby minimizing the potential for abuse. Moreover, the long-term safety of NRTs has been extensively studied and documented. The vast majority of tobacco and nicotine products available in the market currently contain nicotine derived from tobacco leaves. However, advancements in the chemical synthesis of nicotine have introduced an economically viable alternative source. The tobacco industry has been exploiting synthetic nicotine to circumvent existing tobacco control laws and regulations. The emergence of newer tobacco and recreational nicotine products, along with synthetic nicotine, pose a tangible threat to established tobacco control policies. Nicotine regulations need to be responsive to address these evolving challenges. As such, governments should regulate all tobacco and non-medical nicotine products through a global, comprehensive, and consistent approach in order to safeguard tobacco control progress in past decades.

Investigating the impact of smoking habits through photoplethysmography analysis

Smoking is widely recognized as a significant risk factor in the progression of arterial stiffness and cardiovascular diseases. Valuable information related to cardiac arrhythmias and heart function can be obtained by analyzing biosignals such as the electrocardiogram (ECG) and the photoplethysmogram (PPG). The PPG signal is a non-invasive optical technique that can be used to evaluate the changes in blood volume, and thus it can be linked to the health of the vascular system.Objective. In this study, the impact of three smoking habits-cigarettes, shisha, and electronic cigarettes (e-cigarettes)-on the features of the PPG signal were investigated.Approach. The PPG signals are measured for 45 healthy smokers before, during, and after the smoking session and then processed to extract the morphological features. Quantitative statistical techniques were used to analyze the PPG features and provide the most significant features of the three smoking habits. The impact of smoking is observed through significant changes in the features of the PPG signal, indicating blood volume instability.Main results. The results revealed that the three smoking habits influence the characteristics of the PPG signal significantly, which presentseven after 15 min of smoking. Among them, shisha has the greatest impact on PPG features, particularly on heart rate, systolic time, augmentation index, and peak pulse interval change. In contrast, e-cigarettes have the least effect on PPG features. Interestingly, smoking electronic cigarettes, which many participants use as a substitute for traditional cigarettes when attempting to quit smoking, has nearly a comparable effect to regular smoking.Significance. The findings suggest that individuals who smoke shisha are more likely to develop cardiovascular diseases at an earlier age compared to those who have other smoking habits. Understanding the variations in the PPG signal caused by smoking can aid in the early detection of cardiovascular disorders and provide insight into cardiac conditions. This ultimately contributes to the prevention of the development of cardiovascular diseases and the development of a health screening system.

Measuring Suite for Vascular Response Monitoring during Hyperbaric Oxygen Therapy by Means of Pulse Transit Time (PTT) Analysis

The efficacy of hyperbaric oxygen therapy in treating wound healing disorders is well established. The obvious explanation is the presence of elevated oxygen tissue tensions during the high-pressure oxygen exposure. This explanation omits that the effective agent, elevated oxygen tension, is only present for 6.25% of the time. To investigate possible prevailing vascular changes caused by HBOT, the presented device monitors the vascular response during therapy by Pulse-Transit-Time analysis. The device allows synchronous 1 kHz ECG and PPG measurements. The data are stored in a 1 GBit flash drive and retrieved post-therapy. Normoxic measurements on the authors with and without nicotine validate the device's functionality. Measurements during HBO therapy have been successfully performed.

CIGARETTE SMOKING IS ASSOCIATED WITH DECREASED MORTALITY IN CRITICALLY ILL TRAUMA PATIENTS

ABSTRACT

Background: Smoking may offer pathophysiologic adaptations that increase survivability in certain patients with cardiovascular disease. We sought to identify if smoking increases survivability in trauma patients, hypothesizing that critically ill trauma patients who smoke have a decreased risk of mortality compared with non-smokers. Methods: The Trauma Quality Improvement Program (2010-2016) database was queried for trauma patients with intensive care unit admissions. A multivariable logistic regression model was performed. Results: From the 630,278 critically ill trauma patients identified, 116,068 (18.4%) were current cigarette smokers. Critically ill trauma smokers, compared with non-smokers, had a higher rate of pneumonia (7.8% vs. 6.9%, P< 0.001) and lower mortality rate (4.0% vs. 8.0%, P< 0.001). After controlling for covariates, smokers had a decreased associated risk of mortality compared with non-smokers (OR = 0.55, CI = 0.51-0.60, P< 0.001), and no difference in the risk of major complications (OR = 0.98, CI = 0.931.03, P = 0.44). The same analysis was performed using age as a continuous variable with associated decreased risk of mortality (OR 0.57 (CI 0.53-0.62), P< 0.001). Conclusion: Critically ill trauma smokers had a decreased associated mortality risk compared with non-smokers possibly due to biologic adaptations such as increased oxygen delivery developed from smoking. Future basic science and translational studies are needed to pursue potential novel therapeutic benefits without the deleterious long-term side effects of smoking.

Effects of Occupational Stress and Health Behaviors on Heart Rate Variability in Live-Fire Instructors

OBJECTIVES

This study aimed to identify the association between the healthrelated characteristics and the subscales of occupational stress of live fire instructors and heart rate variability (HRV).

METHODS

We conducted questionnaire survey on a general health checkup for 15 live fire instructors. Occupational stress and HRV parameters were measured to determine the association between health behavior, including smoking, drinking, exercise, and sleep-related disorders, and occupational stress of live fire instructors and HRV parameters using Spearman's rank correlation coefficient.

RESULTS

Smoking, insomnia, and job insecurity, a subscale of occupational stress measurement, showed negative Spearman rank correlations with HRV.

CONCLUSIONS

Insomnia, smoking, and job insecurity (due to occupational stress) among live fire instructors were associated with decreased HRV.

Diet, Lifestyle, Smoking

Cardiovascular disease is the leading cause of death globally The past few decades have shown that especially low- and middle-income countries have undergone rapid industrialization, urbanization, economic development and market globalization. Although these developments led to many positive changes in health outcomes and increased life expectancies, they all also caused inappropriate dietary patterns, physical inactivity and obesity. Evidence shows that a large proportion of the cardiovascular disease burden can be explained by behavioural factors such as low physical activity, unhealthy diet and smoking. Controlling these risk factors from early ages is important for maintaining cardiovascular health. Even in patients with genetic susceptibility to cardiovascular disease, risk factor modification is beneficial.Despite the tremendous advances in the medical treatment of cardiovascular risk factors to reduce overall cardiovascular risk, the modern lifestyle which has led to greater sedentary time, lower participation in active transport and time spent in leisure or purposeful physical activity, unhealthy diets and increased exposure to stress, noise and pollution have diminished the beneficial effects of contemporary medical cardiovascular prevention strategies. Therefore attenuating or eliminating these health risk behaviours and risk factors is imperative in the prevention of cardiovascular diseases.

Tobacco Use and Periodontal Disease-The Role of Microvascular Dysfunction

Periodontal disease consists in highly prevalent wide-ranging inflammatory conditions that affect the supporting apparatus of teeth. Tobacco use is the most important risk factor for periodontal disease as it increases disease severity and periodontal surgery complications. Tobacco use is harmful for the vasculature by causing microvascular dysfunction, which is known to negatively affect periodontal disease. To the author's knowledge this paper is the first comprehensive review on the mechanisms by which tobacco use affects oral microcirculation and impacts the pathophysiology of periodontal disease. In healthy subjects, acute nicotine administration or tobacco use (smoking/smokeless forms) increases the blood flow in the oral mucosa due to local irritation and increased blood pressure, which overcome neural- and endocrine-mediated vasoconstriction. Chronic tobacco smokers display an increased gingival microvascular density, which is attributed to an increased capillary recruitment, however, these microcirculatory units show higher tortuosity and lower caliber. These morphological changes, together with the repetitive vasoconstrictive insults, contribute to lower gingival perfusion in chronic smokers and do not completely regress upon smoking cessation. In periodontal disease there is considerable gingival inflammation and angiogenesis in non-smokers which, in chronic smokers, are considerably suppressed, in part due to local immune suppression and oxidative stress. Tobacco exposure, irrespective of the form of use, causes long-term microvascular dysfunction that increases the risk of complications due to the natural disease course or secondary therapeutic strategies.

Smoking may be more harmful to vasospastic angina patients who take antiplatelet agents due to the interaction: Results of Korean prospective multi-center cohort

Background

The interaction between smoking and the use of antiplatelet agents on the prognosis of vasospastic angina (VA) is rarely investigated.

Methods

VA-Korea is a nation-wide multi-center registry with prospective design (n = 1812). The primary endpoint was the composite occurrence of acute coronary syndrome (ACS), symptomatic arrhythmia, and cardiac death. Log-rank test and Cox proportional hazard model were for statistical analysis. Also, we conducted interaction analysis in both additive and multiplicative scales between smoking and antiplatelet agents among VA patients. For additive scale interaction, relative excess risk due to interaction (RERI) was calculated and for multiplicative scale interaction, the ratio of hazard ratio (HR) was calculated. All statistical analysis conducted by Stata Ver 16.1.

Results

Patients who were smoking and using antiplatelet agents had the highest incidence rate in the primary composite outcome. The incidence rate was 3.49 per 1,000 person-month (95% CI: 2.30-5.30, log-rank test for primary outcome p = 0.017) and HR of smoking and using antiplatelet agents was 1.66 (95%CI: 0.98-2.81). The adjusted RERI of smoking and using antiplatelet agents was 1.10 (p = 0.009), and the adjusted ratio of HR of smoking and using antiplatelet agents was 3.32 (p = 0.019). The current study observed the interaction between smoking and using antiplatelet agents in both additive and multiplicative scales.

Conclusions

Smoking was associated with higher rates of unfavorable clinical outcomes among VA patients taking antiplatelet agents. This suggested that VA patients, especially those using antiplatelet agents should quit smoking.

Prevalence and factors that are associated with elevated blood pressure among primary school children in Mwanza Region, Tanzania

Introduction

hypertension (HTN) among children is reported to be increasing due to sedentary lifestyles. In developed countries the prevalence of paediatric HTN is recorded to be up to 21% while the magnitude of the same is up to 11% in Tanzania. This study aimed to determine the blood pressure profile and factors associated with elevated blood pressure (BP) among children of Mwanza region.

Methods

a cross sectional study involving 742 children aged 6 to 16 years in selected primary schools in Mwanza region was conducted from June to August 2019. Data were collected using self-administered structured questionnaires where parents helped children to fill in. Blood pressure, body weight and height were measured using digital portable sphygmomanometer, self-calibrating digital weighing scale and Shorr measuring board respectively. Data were analyzed using EpiInfo.

Results

this study found mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) were 109.2 ± 8.1 mmHg and 62.3 ± 7.2 mmHg respectively. Prevalence of elevated BP was 18.1%. Pre-hypertension 9.6%, and hypertension 8.5%. The age specific elevated BP prevalence was significantly higher (OR = 1.9, 95% CI: 1.2 - 2.9, p = 0.008) among children aged ≥10 years (21.4%) than younger ones (15.1%). Prevalence was also higher (OR = 1.5, 95% CI: 1.1 - 2.3, p = 0.048) among girls (20.1%) than boys (16.0%). Elevated BP was found to be associated with obesity (OR = 3.5, 95% CI: 1.6 - 7.7, p = <0.001), overweight (OR = 1.9, 95% CI: 1.1 - 3.3, p = 0.037), eating fried food (OR = 2.2, 95% CI: 1.1 - 4.4, p = 0.023), drinking sugar soft drinks (OR = 2.0, 95% CI: 1.2 - 3.5, p = 0.002) and not eating fruits (OR = 13.4, 1.6, 95% CI: 2.1 - 65.8, p-value 0.006).

Conclusion

findings indicate high prevalence of elevated BP among children of Mwanza region. There was an association between elevated BP and increased age, gender, sedentary lifestyle and obesity. Importance of measuring paediatric blood pressure and health information regarding effects of sedentary life is recommended to Tanzanians. Parents should encourage their children to have active physical activities. Moreover, health workers should implement programmes to modify sedentary lifestyle and prevent children from elevated blood pressure.

Immunization Against Oxidized Elastin Exacerbates Structural and Functional Damage in Mouse Model of Smoke-Induced Ocular Injury

Purpose

Age-related macular degeneration (AMD) is the leading cause of blindness in Western populations. While an overactive complement system has been linked to pathogenesis, mechanisms contributing to its activation are largely unknown. In aged and AMD eyes, loss of the elastin layer (EL) of Bruch's membrane (BrM) has been reported. Elastin antibodies are elevated in patients with AMD, the pathogenic significance of which is unclear. Here we assess the role of elastin antibodies using a mouse model of smoke-induced ocular pathology (SIOP), which similarly demonstrates EL loss.

Methods

C57BL/6J mice were immunized with elastin or elastin peptide oxidatively modified by cigarette smoke (ox-elastin). Mice were then exposed to cigarette smoke or air for 6 months. Visual function was assessed by optokinetic response, retinal morphology by spectral-domain optical coherence tomography and electron microscopy, and complement activation and antibody deposition by Western blot.

Results

Ox-elastin IgG and IgM antibodies were elevated in ox-elastin immunized mice following 6 months of smoke, whereas elastin immunization had a smaller effect. Ox-elastin immunization exacerbated smoke-induced vision loss, with thicker BrM and more damaged retinal pigment epithelium (RPE) mitochondria compared with mice immunized with elastin or nonimmunized controls. These changes were correlated with increased levels of IgM, IgG2, IgG3, and complement activation products in RPE/choroid.

Conclusions

These data demonstrate that SIOP mice generate elastin-specific antibodies and that immunization with ox-elastin exacerbates ocular pathology. Elastin antibodies represented complement fixing isotypes that, together with the increased presence of complement activation seen in immunized mice, suggest that elastin antibodies exert pathogenic effects through mediating complement activation.

Associations of Smoke-Free Policies in Restaurants, Bars, and Workplaces With Blood Pressure Changes in the CARDIA Study

Background

Smoke‐free legislation has been associated with reductions in secondhand smoke exposure and cardiovascular disease. However, it remains unknown whether smoke‐free policies are associated with reductions in blood pressure (BP).

Methods and Results

Longitudinal data from 2606 nonsmoking adult participants of the CARDIA (Coronary Artery Risk Development in Young Adults) Study (1995–2011) were linked to state, county, and local‐level 100% smoke‐free policies in bars, restaurants, and/or nonhospitality workplaces based on participants’ census tract of residence. Mixed‐effects models estimated associations of policies with BP and hypertension trajectories over 15 years of follow‐up. Fixed‐effects regression estimated associations of smoke‐free policies with within‐person changes in systolic and diastolic BP and hypertension. Models were adjusted for sociodemographic, health‐related, and policy/geographic covariates. Smoke‐free policies were associated with between‐person differences and within‐person changes in systolic BP. Participants living in areas with smoke‐free policies had lower systolic BP on average at the end of follow‐up compared with those in areas without policies (adjusted predicted mean differences [in mm Hg]: restaurant: −1.14 [95% confidence interval: −2.15, −0.12]; bar: −1.52 [−2.48, −0.57]; workplace: −1.41 [−2.32, −0.50]). Smoke‐free policies in restaurants and bars were associated with mean within‐person reductions in systolic BP of −0.85 (−1.61, −0.09) and −1.08 (−1.82, −0.34), respectively. Only restaurant policies were associated with a significant within‐person reduction in diastolic BP, of −0.58 (−1.15, −0.01).

Conclusions

While the magnitude of associations was small at the individual level, results suggest a potential mechanism through which reductions in secondhand smoke because of smoke‐free policies may improve population‐level cardiovascular health.

See Editorial by https://10.1161/JAHA.118.011120

Smoking is associated with an improved short-term outcome in patients with rib fractures

BACKGROUND

Smokers with cardiovascular disease have been reported to have decreased mortality compared to non-smokers. Rib fractures are associated with significant underlying injuries such as lung contusions, lacerations, and/or pneumothoraces. We hypothesized that blunt trauma patients with rib fractures who are smokers have decreased ventilator days and risk of in-hospital mortality compared to non-smokers.

STUDY DESIGN

The Trauma Quality Improvement Program (2010-2016) was queried for patients presenting with a blunt rib fracture. Patients that died within 24 h of admission were excluded. A multivariable logistic regression model was performed.

RESULTS

From 282,986 patients with rib fractures, 57,619 (20.4%) were smokers. Compared to non-smokers with rib fractures, smokers had a higher median injury severity score (17 vs. 16, p < 0.001). Smokers had a higher rate of pneumonia (7.5% vs. 6.6%, p < 0.001), however, less ventilator days (5 vs. 6, p = 0.04), and lower in-hospital mortality rate (2.3% vs. 4.6%, p < 0.001), compared to non-smokers. After controlling for covariates, smokers with rib fractures were associated with a decreased risk for in-hospital mortality compared to non-smokers with rib fractures (OR 0.64, 0.56-0.73, p < 0.001).

CONCLUSION

Despite having more severe injuries and increased rates of pneumonia, smokers with rib fractures were associated with nearly a 40% decreased risk of in-hospital mortality and one less ventilator day compared to non-smokers. The long-term detrimental effects of smoking have been widely established. However, the biologic and pathophysiologic adaptations that smokers have may confer a survival benefit when recovering in the hospital from chest wall trauma. This study was limited by the database missing the number of pack-years smoked. Future prospective studies are needed to confirm this association and elucidate the physiologic mechanisms that may explain these findings.

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.

Association of exposure level to passive smoking with hypertension among lifetime nonsmokers in Japan: a cross-sectional study

Brief exposure to passive smoking immediately elevates blood pressure. However, little is known about the association between exposure to passive smoking and chronic hypertension. We aimed to examine this association in a cross-sectional study, after controlling multiple potential confounders.Participants included 32,098 lifetime nonsmokers (7,216 men and 24,882 women) enrolled in the Japan Multi-Institutional Collaborative Cohort Study. Passive smoking was assessed using a self-administered questionnaire. The single question about exposure to passive smoking had five response options: "sometimes or almost never," "almost every day, 2 hours/day or less," "almost every day, 2 to 4 hours/day," "almost every day, 4 to 6 hours/day," and "almost every day, 6 hours/day or longer." Hypertension was defined as any of the following: systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg, or use of antihypertensive medication. Multivariate-adjusted odds ratio (OR) and 95% confidence interval (CI) for hypertension were estimated by exposure level to passive smoking using unconditional logistic regression models.The multivariate-adjusted OR for hypertension in those exposed almost every day was 1.11 (95% CI: 1.03-1.20) compared with those exposed sometimes or almost never. The OR for a 1-hour per day increase in exposure was 1.03 (95% CI: 1.01-1.06, Pfor trend = .006). This association was stronger in men than in women; the ORs were 1.08 (95% CI: 1.01-1.15, Pfor trend = .036) and 1.03 (95% CI: 1.00-1.05, Pfor trend = .055), respectively.Our findings suggest importance of tobacco smoke control for preventing hypertension.

Melatonin attenuates thiocyanate-induced vasoconstriction in aortic rings

Cigarette smoking not only has a carcinogenic effect but also leads to an increase in arterial blood pressure. Besides its main components, i.e. nicotine, tar, and carbon monoxide, cigarette smoke also contains thiocyanate. Thiocyanate anions (SCN^-) arise from the detoxification of hydrogen cyanide and its plasma concentrations were found to correlate significantly with cigarette consumption. There is also evidence that atherosclerotic disease progression is much more rapid when serum SCN^- levels are increased. Melatonin, a non-toxic indolamine with various physiologic functions, is believed to protect against inflammatory processes and oxidative stress. It has been demonstrated that melatonin serves as free radical scavenger and represents a potent antioxidant. Therefore, it is believed that melatonin with its atheroprotective effects may be useful either as a sole therapy or in conjunction with others. The aim of this study was to quantify the thiocyanate-induced vasomotor response in aortic tissue and further to examine the potential of melatonin in affecting the generated vasoreactivity. Aortic rings of adult male normotensive Wistar rats were cut into 4-mm rings. Following the administration of thiocyanate in various concentrations, vasomotor response of aortic vessel segments was measured. To assess the effect of melatonin on vasomotor activity, organ bath concentrations were modulated from 60 to 360 pM, which corresponds to physiologic plasma up to the levels of patients with regular oral intake of 3 mg of melatonin as a supplement. Thirty-six rat aortic rings were studied. When exposed to thiocyanate, vessel segments revealed vasoconstriction in a concentration-dependent manner. In rings which were preincubated with melatonin at a concentration of 360 pM, a 56.5% reduction of effect size could be achieved (4.09 ± 1.22 mN versus 9.41 ± 1.74 mN, P < 0.0001). Additionally, administration of 360 pM melatonin at a norepinephrine concentration of 80 mM resulted in a relaxation of 10.9 ± 2.2%. The vasodilatatory effect of melatonin was significantly reduced to 1.3 ± 0.5% when concentration of norepinephrine was doubled (P < 0.002). This study indicates that vessel segments that were exposed to thiocyanate responded with a dose-dependent vasoconstriction. The effect could be markedly attenuated in segments preincubated in melatonin.

The Association of Cigarette Smoking With High-Frequency Heart Rate Variability: An Ecological Momentary Assessment Study

OBJECTIVE

Evidence from both laboratory and observational studies suggests that acute and chronic smoking leads to reduced high-frequency heart rate variability (HF-HRV), a measure of cardiac vagal regulation. We used ecological momentary assessment (EMA) to study the effect of smoking on concurrent HF-HRV in a trial measuring the effects of hostility reduction and compared 24-hour HF-HRV in smokers and nonsmokers.

METHOD

Ambulatory electrocardiogram data were collected before randomization from 149 healthy individuals with high hostility levels (20-45 years, body mass index ≤ 32 kg/m) and paired with concurrent EMA ratings of smoking and physical position during waking hours. A multilevel mixed model was estimated associating ln(HF-HRV) from smoking status (between-person factor) and person-centered momentary smoking (within-person factor, treated as a random effect), adjusting for momentary physical position, medication use, and consumption of alcohol and caffeine.

RESULTS

Thirty-five smokers and 114 nonsmokers provided both EMA and HF-HRV data. Within smokers, ln HF-HRV was reduced by 0.31 millisecond (p = .04) when participants reported having recently smoked cigarettes, compared with when they had not. The 24-hour HF-HRV was significantly lower in smokers (M [SD] = 5.24 [0.14] milliseconds) than nonsmokers (5.63 ± 0.07 milliseconds, p = .01).

CONCLUSIONS

In healthy smokers with high hostility levels used as their own controls during daily living, smoking acutely reduced HF-HRV. HF-HRV was also reduced in smokers as compared with nonsmokers. Although limited by a small sample of individuals with high hostility levels, these findings nonetheless provide additional evidence that cardiac vagal regulation is lowered by cigarette smoking, which may be one of the numerous pathophysiological effects of smoking.

Association of Smoking Status With Angina and Health-Related Quality of Life After Acute Myocardial Infarction

BACKGROUND

Smoking cessation after acute myocardial infarction (AMI) decreases the risk of recurrent AMI and mortality by 30% to 50%, but many patients continue to smoke. The association of smoking with angina and health-related quality of life (HRQOL) after AMI is unclear.

METHODS AND RESULTS

Patients in 2 US multicenter AMI registries (n=4003) were assessed for smoking and HRQOL at admission and 1, 6, and 12 months after AMI. Angina and HRQOL were measured with the Seattle Angina Questionnaire and Short Form-12 Physical and Mental Component Scales. At admission, 29% never had smoked, 34% were former smokers (quit before AMI), and 37% were active smokers, of whom 46% quit by 1 year (recent quitters). In hierarchical, multivariable, regression models that adjusted for sociodemographic, clinical and treatment factors, never and former smokers had similar and the best HRQOL in all domains. Recent quitters had intermediate HRQOL levels, with angina and Short Form-12 Mental Component Scale scores similar to never smokers. Persistent smokers had worse HRQOL in all domains compared with never smokers and worse Short Form-12 Mental Component Scale scores than recent quitters.

CONCLUSIONS

Smoking after AMI is associated with more angina and worse HRQOL in all domains, whereas smokers who quit after AMI have similar angina levels and mental health as never smokers. These observations may help encourage patients to stop smoking after AMI.

Cerebral oxygenation and sympathetic responses to smoking in young and middle-aged smokers

This study examined the effects of acute tobacco smoking on cerebral oxygenation and autonomic function in 28 male, habitual smokers of shorter young smokers (YSM) or longer middle-aged smokers (MSM) smoking history. Following baseline testing, participants undertook a smoking protocol involving the consumption of two cigarettes within 15 min. Measures of cerebral oxygenation and autonomic function were collected before, during, and 0 min, 30 min, 1 h, and 4 h post-smoking. Tissue saturation index (TSI) for MSM was greater than YSM during cigarette consumption ( p < 0.05). Moreover, MSM observed significant within-group changes for TSI during and post-cigarette consumption ( p < 0.05). Further, MSM observed an increase in low frequency (LF) band from 30 min to 1 h post-consumption, followed by a decline, whereas elevations above MSM were observed in YSM at 4 h ( p < 0.05). Both MSM and YSM showed a decrease in high-frequency (HF) band post-cigarette, while increased LF/HF ratio post-consumption was observed in YSM. A decline in the standard deviation of RR intervals, post-cigarette consumption was evident in MSM ( p < 0.05). Moreover, the root mean square of RR interval in both groups similarly decreased following cigarette consumption ( p < 0.05). Acute smoking affects heart rate variability, suggestive of vagal withdrawal, and maybe indicate an effect of smoking history. Additionally, prolonged smoking history alters cerebral microcirculatory responses to acute tobacco exposure in MSM.

The Effects of Acute Passive Smoke Exposure on Endothelium-Dependent Brachial Artery Dilation in Healthy Individuals

Passive smoking has both short-term and long-term vascular effects. It is not clear whether impairment of endothelial function reflects the acute effects of passive smoke exposure or the chronic effects. The purpose of this study was to assess the hypothesis that short-term exposure to passive smoke impairs endothelium-dependent vasodilation in healthy nonsmokers. Eighteen healthy young never smokers (12 men, 6 women) 21 to 55 years old (mean ± SD: 34 ±9 years) underwent ultrasonography measuring baseline brachial-artery diameter and brachial-artery diameter during hyperemia and after sublingual administration of nitroglycerin, twice: in a smoke-free environment, and then in the same environment polluted by 30 to 35 ppm carbon monoxide. Each subject served as his/her control. Carboxyhemoglobin was measured in blood samples of subjects tested. Mean value of carboxyhemoglobin was 0.6 ±0.5% in a smoke-free environment and 1.4 ± 0.5% in a smoking environment (p <0.02). Mean values of flow-mediated dilation (FMD) were 12.6% ± 7.8% in a smoke-free environment versus 6.8 ± 7.8% in a smoking environment (p <0.01). On the contrary, nitroglycerin-induced vasodilation did not show any statistical difference (21 ± 9.8% versus 23 ±1.4%). Finally, the increase of carboxyhemoglobin was related statistically to the impairment of flow-mediated dilation (r = 0.51; p <0.002). Passive smoking impaired flow-mediated vasodilation in healthy never smokers in a smoking environment. The impairment was strongly related to carboxyhemoglobin level.

Forced Expiratory Volume in the First Second and Aldosterone as Mediators of Smoking Effect on Stroke in African Americans: The Jackson Heart Study

BACKGROUND

Cigarette smoking is a risk factor for stroke, but the mechanisms by which smoking contributes to stroke are not well understood. This study aimed to evaluate the roles of lung function (represented by forced expiratory volume in the first second (FEV1)) and aldosterone as potential mediators of the association of smoking with stroke.

METHODS AND RESULTS

The data were derived from 5010 Jackson Heart Study participants who had mean follow-up of 97.9 months. Using the Cox proportional hazards model, we estimated the hazard ratios of smoking for total stroke with and without adjustment for FEV1 and/or aldosterone at baseline after controlling for the confounders. The hazard ratio for current smoking (versus never smoking) was 2.70 (95% CI 1.71 to 4.25) for total stroke after adjustment for the confounders. Additional adjustment for FEV1 and aldosterone reduced the hazard ratio to 2.32 (95% CI 1.42 to 3.79), suggesting that 22.4% of the excess risk of current smoking for total stroke is mediated by these factors. FEV1 and aldosterone account for 13.1% and 12.1%, respectively, of the excess risk. The hazard ratio for FEV1 increased (0.61 versus 0.65) after including systemic inflammatory marker C-reactive protein, and the hazard ratios for aldosterone were comparable for the models that included all confounders and smoking status with or without different blood pressure measurements.

CONCLUSIONS

Our findings suggest that the difference in stroke risk between current and never smokers may develop partially through pathways involving lung function and aldosterone and that the mediation effect through aldosterone is independent of blood pressure.

Tobacco and e-cigarette products initiate Kupffer cell inflammatory responses

Kupffer cells are liver resident macrophages that are responsible for screening and clearing blood of pathogens and foreign particles. It has recently been shown that Kupffer cells interact with platelets, through an adhesion based mechanism, to aid in pathogen clearance and then these platelets re-enter the general systemic circulation. Thus, a mechanism has been identified that relates liver inflammation to possible changes in the systemic circulation. However, the role that Kupffer cells play in cardiovascular disease initiation/progression has not been elucidated. Thus, our objective was to determine whether or not Kupffer cells are responsive to a classical cardiovascular risk factor and if these changes can be transmitted into the general systemic circulation. If Kupffer cells initiate inflammatory responses after exposure to classical cardiovascular risk factors, then this provides a potential alternative/synergistic pathway for cardiovascular disease initiation. We aimed to elucidate the prevalence of this potential pathway. We hypothesized that Kupffer cells would initiate a robust inflammatory response after exposure to tobacco cigarette or e-cigarette products and that the inflammatory response would have the potential to antagonize other salient cells for cardiovascular disease progression. To test this, Kupffer cells were incubated with tobacco smoke extracts, e-cigarette vapor extracts or pure nicotine. Complement deposition onto Kupffer cells, Kupffer cell complement receptor expression, oxidative stress production, cytokine release and viability and density were assessed after the exposure. We observed a robust inflammatory response, oxidative stress production and cytokine release after Kupffer cells were exposed to tobacco or e-cigarette extracts. We also observed a marginal decrease in cell viability coupled with a significant decrease in cell density. In general, this was not a function of the extract formulation (e.g. tobacco vs. e-cigarette products or the formulation of the cigarette product). These results indicate that Kupffer cells are responsive to classical cardiovascular risk factors and that an inflammatory response is initiated that may pass into the general systemic circulation.

Nicotine effect on bone remodeling during orthodontic tooth movement: histological study in rats

INTRODUCTION

Nicotine is harmful to angiogenesis, osteogenesis and synthesis of collagen.

OBJECTIVE

The aim of this study was to investigate the effect of nicotine on bone remodeling during orthodontic movement in rats.

METHODS

Eighty male Wistar rats were randomly divided into three groups: Group C (control), group CM (with orthodontic movement) and group NM (nicotine with orthodontic movement) groups. The animals comprising groups C and CM received 0.9% saline solution while group NM received nicotine solution (2 mg/kg). A nickel-titanium closed-coil spring was used to induce tooth movement. The animals were euthanized and tissue specimens were histologically processed. Blood vessels, Howship's lacunae and osteoclast-like cells present in the tension and compression areas of periodontal ligaments were quantified. The extent of bone formation was evaluated under polarized light, to determine the percentage of immature/mature collagen.

RESULTS

It was observed lower blood vessel densities in the NM group in comparison to the CM group, three (p < 0.001) and seven (p < 0.05) days after force application. Osteoclast-like cells and Howship's lacunae in the NM group presented lower levels of expression, in comparison to the CM group, with significant differences on day 7 (p < 0.05 for both variables) and day 14 (p < 0.05 for osteoclast-like cells and p < 0.01 for Howship's lacunae). The percentage of immature collagen was increased in the NM group in comparison to the CM group, with a statistically significant difference on day 3 (p < 0.05), day 7 (p < 0.001), day 14 (p < 0.001) and day 21 (p < 0.001).

CONCLUSIONS

Nicotine affects bone remodeling during orthodontic movement, reducing angiogenesis, osteoclast-like cells and Howship's lacunae, thereby delaying the collagen maturation process in new bone matrix.

"Smoker's Paradox" in Patients Treated for Severe Injuries: Lower Risk of Mortality After Trauma Observed in Current Smokers

BACKGROUND

Studies evaluating the effect of smoking status on mortality outcomes in trauma patients have been limited, despite the fact that survival benefits of smoking have been reported in other critical care settings. The phenomenon "smoker's paradox" refers to the observation that following acute cardiovascular events, such as acute myocardial infarction and cardiac arrest, smokers often experience decreased mortality in the hospital setting. The objective of our study was to determine whether smoking imparts a survival benefit in patients with traumatic injuries.

METHODS

We performed a retrospective cohort study that analyzed cases included in the National Trauma Data Bank research dataset. Hierarchical logistic regression analyses were used to determine whether smoking alters the risk of mortality and complications in patients who smoke.

RESULTS

The percentage of patients experiencing mortality differed significantly between smokers (n = 38,564) and nonsmokers (n = 319,249) (1.8% vs. 4.3%, P < .001); however, the percentage experiencing a major complication did not (9.7% vs. 9.6%, P = .763). Regression analyses indicated that smokers were significantly less likely to die during the hospital stay compared to nonsmokers after adjusting for individual and hospital factors (OR = 0.15; CI = 0.10, 0.22). Additionally, smokers were also less likely to develop a major complication than nonsmokers (OR = 0.73, CI = 0.59-0.91).

CONCLUSIONS

Patients who smoke appear to have a much lower risk of in-hospital mortality than nonsmokers. Further investigation into biological mechanisms responsible for this effect should be carried out in order to potentially develop therapeutic applications.

Smoking and age-related macular degeneration: review and update

Age-related macular degeneration (AMD) is one of the main socioeconomical health issues worldwide. AMD has a multifactorial etiology with a variety of risk factors. Smoking is the most important modifiable risk factor for AMD development and progression. The present review summarizes the epidemiological studies evaluating the association between smoking and AMD, the mechanisms through which smoking induces damage to the chorioretinal tissues, and the relevance of advising patients to quit smoking for their visual health.

Mechanisms of Coronary Thrombosis in Cigarette Smoke Exposure

Acute rupture or erosion of a coronary atheromatous plaque and subsequent coronary artery thrombosis cause the majority of sudden cardiac deaths and myocardial infarctions. Cigarette smoking is a major risk factor for acute coronary thrombosis. Indeed, a majority of sudden cardiac deaths attributable to acute thrombosis are in cigarette smokers. Both active and passive cigarette smoke exposure seem to increase the risk of coronary thrombosis and myocardial infarctions. Cigarette smoke exposure seems to alter the hemostatic process via multiple mechanisms, which include alteration of the function of endothelial cells, platelets, fibrinogen, and coagulation factors. This creates an imbalance of antithrombotic/prothrombotic factors and profibrinolytic/antifibrinolytic factors that support the initiation and propagation of thrombosis.

Alternative complement pathway deficiency ameliorates chronic smoke-induced functional and morphological ocular injury

BACKGROUND

Age-related macular degeneration (AMD), a complex disease involving genetic variants and environmental insults, is among the leading causes of blindness in Western populations. Genetic and histologic evidence implicate the complement system in AMD pathogenesis; and smoking is the major environmental risk factor associated with increased disease risk. Although previous studies have demonstrated that cigarette smoke exposure (CE) causes retinal pigment epithelium (RPE) defects in mice, and smoking leads to complement activation in patients, it is unknown whether complement activation is causative in the development of CE pathology; and if so, which complement pathway is required.

METHODS

Mice were exposed to cigarette smoke or clean, filtered air for 6 months. The effects of CE were analyzed in wildtype (WT) mice or mice without a functional complement alternative pathway (AP; CFB(-/-) ) using molecular, histological, electrophysiological, and behavioral outcomes.

RESULTS

CE in WT mice exhibited a significant reduction in function of both rods and cones as determined by electroretinography and contrast sensitivity measurements, concomitant with a thinning of the nuclear layers as measured by SD-OCT imaging and histology. Gene expression analyses suggested that alterations in both photoreceptors and RPE/choroid might contribute to the observed loss of function, and visualization of complement C3d deposition implies the RPE/Bruch's membrane (BrM) complex as the target of AP activity. RPE/BrM alterations include an increase in mitochondrial size concomitant with an apical shift in mitochondrial distribution within the RPE and a thickening of BrM. CFB(-/-) mice were protected from developing these CE-mediated alterations.

CONCLUSIONS

Taken together, these findings provide clear evidence that ocular pathology generated in CE mice is dependent on complement activation and requires the AP. Identifying animal models with RPE/BrM damage and verifying which aspects of pathology are dependent upon complement activation is essential for developing novel complement-based treatment approaches for the treatment of AMD.

Is the primary mechanism underlying COPD: inflammation or ischaemia?

The mechanisms underlying the majority of COPD cases have remained ill-defined. Cigarette smoke contains many toxic chemicals that certainly cause some inflammatory responses, but this article advances a hypothesis that the nicotine and similar compounds within the smoke acting as vasoconstrictors of bronchiolar arterioles may be more important via multiple small infarcts that eventually destroy lung tissue. The hypothesis can explain many of the known features of COPD and if accepted would significantly alter the approach to this condition.

Serum cotinine levels and prehypertension in never smokers

Background. Few studies have shown that self-reported secondhand smoke exposure in never smokers is associated with high blood pressure. However, there are no studies investigating the relationship between secondhand smoke exposure, measured objectively by serum cotinine levels, and high blood pressure in never smokers. Methods. We examined never smokers (n = 2027) from the National Health and Nutrition Examination Survey 2005–2008. Our exposure of interest was the secondhand smoke exposure estimated by serum cotinine level and our outcome was prehypertension (n = 734), defined as a systolic blood pressure of 120–139 mmHg or diastolic blood pressure of 80–89 mmHg. Results. We found that, in never smokers, serum cotinine levels were positively associated with prehypertension. Compared to those with cotinine levels in the lowest quartile (≤0.024 ng/mL), the multivariable odds ratio (95% confidence interval) of prehypertension among those with cotinine levels in the highest quartile (≥0.224 ng/mL) was 1.45(1.00, 2.11); P trend = 0.0451. In subsequent subgroup analyses, the positive association was found to be stronger among men, non-Whites, and non-obese subjects. Conclusion. Higher secondhand smoke exposure measured objectively by serum cotinine levels was found to be associated with prehypertension in certain subgroups of a representative sample of the US population.

The biology behind the atherothrombotic effects of cigarette smoke

Cigarette smoke is an aerosol that contains >4,000 chemicals, including nicotine, carbon monoxide, acrolein, and oxidant compounds. Exposure to cigarette smoke induces multiple pathological effects in the endothelium, several of which are the result of oxidative stress initiated by reactive oxygen species, reactive nitrogen species, and other oxidant constituents of cigarette smoke. Cigarette-smoke exposure interferes adversely with the control of all stages of plaque formation and development and pathological thrombus formation. The reactive oxygen species in cigarette smoke contribute to oxidative stress, upregulation of inflammatory cytokines, and endothelial dysfunction, by reducing the bioavailability of nitric oxide. Plaque formation and the development of vulnerable plaques also result from exposure to cigarette smoke via the enhancement of inflammatory processes and the activation of matrix metalloproteases. Moreover, exposure to cigarette smoke results in platelet activation, stimulation of the coagulation cascade, and impairment of anticoagulative fibrinolysis. Many cigarette-smoke-mediated prothrombotic changes are quickly reversible upon smoking cessation. Public health efforts should urgently promote our understanding of current cigarette-smoke-induced cardiovascular pathology to encourage individuals to reduce their exposure to cigarette smoke and, therefore, the detrimental consequences of associated atherothrombotic disease.

Acute electrocardiographic changes during smoking: an observational study

OBJECTIVE

To study the temporal relationship of smoking with electrophysiological changes.

DESIGN

Prospective observational study.

SETTING

Tertiary cardiac center.

PARTICIPANTS

Male smokers with atypical chest pain were screened with a treadmill exercise test (TMT). A total of 31 such patients aged 49.8±10.5 years, in whom TMT was either negative or mildly positive were included. Heart rate variability (HRV) parameters of smokers were compared to those of 15 healthy non-smoking participants.

INTERVENTIONS

All patients underwent a 24 h Holter monitoring to assess ECG changes during smoking periods.

RESULTS

Heart rate increased acutely during smoking. Mean heart rate increased from 83.8±13.7 bpm 10 min before smoking, to 90.5±16.4 bpm during smoking, (p<0.0001) and returned to baseline after 30 min. Smoking was also associated with increased ectopic beats (mean of 5.3/h prior to smoking to 9.8/h during smoking to 11.3/h during the hour after smoking; p<0.001). Three patients (9.7%) had significant ST-T changes after smoking. HRV index significantly decreased in smokers (15.2±5.3) as compared to non-smoking controls participants (19.4±3.6; p=0.02), but the other spectral HRV parameters were comparable.

CONCLUSIONS

Heart rate and ectopic beats increase acutely following smoking. Ischaemic ST-T changes were also detected during smoking. Spectral parameters of HRV analysis of smokers remained in normal limits, but more importantly geometrical parameter-HRV index-showed significant abnormality.

Cardiac autonomic function in healthy young smokers

The present study examined the heart rate turbulence (HRT) and heart rate variability (HRV) parameters in healthy young smokers (<40 years) to assess the effects of smoking on cardiac autonomic function. The study included 75 smokers with a history of habitual smoking for at least 1 year (41 males and 34 females; mean age, 29.3 ± 7.3 years) and 30 nonsmokers (hospital staff; 16 males and 14 females; mean age, 29.0 ± 6.1 years). Addiction to smoking was evaluated using the modified Fagerström test for nicotine-dependence index (NDI). HRT, HRV, basic clinical and echocardiographic, and Holter test parameters were compared between groups. No significant differences between the two groups were found in the basic clinical and echocardiographic variables. Turbulence onset (TO) was significantly higher in the smoking group than in the controls, and turbulence slope was significantly lower in the smokers, than in the controls (p < 0.05). Standard deviation of all normal-to-normal (NN) interval index (SDNNI) was the only HRV parameter that was significantly different between the smoking and control groups (p < 0.05). The NDI was positively correlated with the TO (p < 0.05). Smoking impairs the baroregulatory function in healthy young smokers, particularly the HRT parameters and SDNNI. Our findings highlight the importance of complete smoking cessation.

Maternal smoking and increased risk of sudden infant death syndrome: a meta-analysis

Maternal smoking is detrimental to the development of fetuses and neonates. This meta-analysis was performed to measure the accumulated association of sudden infant death syndrome (SIDS) risk with both prenatal and postnatal maternal smoking. The odds ratio (OR) corresponding to the 95% confidence interval (CI) was used to assess the associations between maternal smoking and SIDS risk. The statistical heterogeneity among studies was assessed with the Q-test and I(2) statistics. The data for this meta-analysis were available from 35 case-control studies. The prenatal and postnatal maternal smoking was associated with a significantly increased risk of SIDS (OR=2.25, 95% CI=2.03-2.50 for prenatal maternal smoking analysis, and OR=1.97, 95% CI=1.77-2.19 for postnatal maternal smoking analysis, respectively) by random effects model. After stratified analyses, regardless of prenatal or postnatal smoking, heavy cigarette consumption increased the risk of SIDS and significantly elevated SIDS risk was found to be associated with co-sleeping with postnatal smoking mothers. Our results suggested that maternal smoking were associated with elevated SIDS risk, the effects were dose-dependent. In addition, SIDS risk was significantly increased in infants co-sleeping with postnatal smoking mothers.

Acute and chronic effects of smoking on myocardial function in healthy heavy smokers: a study of Doppler flow, Doppler tissue velocity, and two-dimensional speckle tracking echocardiography

BACKGROUND

The purpose of the study was to evaluate the acute and chronic effect of smoking on left ventricular function in healthy heavy smokers by conventional Doppler flow, tissue Doppler, and two-dimensional speckle tracking echocardiography (2D-STE).

METHODS

Echocardiograms were performed in 42 healthy heavy (>20 cigarettes/day) smokers (age 34 ± 5 years), before (group SM-1), 15 minutes (SM-2) and 30 minutes (SM-3) after starting smoking 2 cigarettes. Nonsmokers (n = 41, age 33 ± 4 years) served as controls. Transmitral flow, isovolumetric relaxation time (IVRT), and myocardial performance index (MPI) were measured. Tissue velocity measurements were averaged from lateral and septal mitral annulus. Longitudinal strain (GS), systolic (SRs), early diastolic (SRe), late diastolic (SRa), and isovolumetric relaxation (SRivr) strain rate were measured. The percent change in strain from end-systole to the first one-third of diastole (SI-DI = [(GS - strain at one-third diastole)/GS] × 100) was also measured.

RESULTS

IVRT and MPI were increased and early diastolic mitral annular velocity was decreased in SM-2; they returned to baseline in SM-3. There was no difference in GS and SRs. SRe and SRivr were reduced in SM-1 (P < 0.05), and remained significantly reduced in SM-2 and SM-3. SI-DI was lower in SM-1 (P = 0.011) and was further reduced in SM-2 and SM-3 (P < 0.001).

CONCLUSION

Acute and chronic smoking inhalation has adverse effects on myocardial function in healthy heavy smokers. 2D-STE is able to detect both baseline differences and late acute effects of smoking.

Association of serum cotinine levels and hypertension in never smokers

Hypertension is a major public health problem. Identifying novel risk factors for hypertension, including widely prevalent environmental exposures, is therefore important. Active smoking is a well-known risk factor for hypertension and cardiovascular diseases. However, there are no studies investigating the relationship between secondhand smoke exposure, measured objectively by serum cotinine, and high blood pressure among never smokers. We examined 2889 never smokers from the National Health and Nutrition Examination Survey 2005-2008. Our exposure of interest was secondhand smoke exposure among never smokers, estimated by serum cotinine level, and our main outcome was hypertension (n=1004). We found that in never smokers, higher serum cotinine levels were positively associated with hypertension. In comparison with those with serum cotinine levels ≤ 0.025 ng/mL, the multivariable odds ratio (95% confidence interval) of hypertension among those with serum cotinine levels ≥ 0.218 ng/mL was 1.44 (1.01-2.04). In addition, higher serum cotinine was positively associated with mean change in systolic blood pressure (odds ratio [95% confidence interval], 3.24 [0.86-5.63]; P=0.0061). However, no association was present with diastolic blood pressure. In conclusion, in never smokers, higher secondhand smoke exposure measured objectively by serum cotinine levels was found to be associated with systolic blood pressure and hypertension independent of age, sex, ethnicity, education, alcohol drinking, body mass index, glycohemoglobin, total cholesterol, and other confounders.

Effects of cigarette smoking on reproduction

BACKGROUND Cigarette smoking is associated with lower fecundity rates, adverse reproductive outcomes and a higher risk of IVF failures. Over the last few decades, prevalence of smoking among women of reproductive age has increased. This review focuses on current knowledge of the potential effects of smoke toxicants on all reproductive stages and the consequences of smoke exposure on reproductive functions. METHODS We conducted a systematic review of the scientific literature on the impact of cigarette smoking and smoke constituents on the different stages of reproductive function, including epidemiological, clinical and experimental studies. We attempted to create hypotheses and find explanations for the deleterious effects of cigarette smoke observed in experimental studies. RESULTS Cigarette smoke contains several thousand components (e.g. nicotine, polycyclic aromatic hydrocarbons and cadmium) with diverse effects. Each stage of reproductive function, folliculogenesis, steroidogenesis, embryo transport, endometrial receptivity, endometrial angiogenesis, uterine blood flow and uterine myometrium is a target for cigarette smoke components. The effects of cigarette smoke are dose-dependent and are influenced by the presence of other toxic substances and hormonal status. Individual sensitivity, dose, time and type of exposure also play a role in the impact of smoke constituents on human fertility. CONCLUSIONS All stages of reproductive functions are targets of cigarette smoke toxicants. Further studies are necessary to better understand the deleterious effects of cigarette smoke compounds on the reproductive system in order to improve health care, help to reduce cigarette smoking and provide a better knowledge of the molecular mechanisms involved in reproductive toxicology.

The pathophysiology of cigarette smoking and age-related macular degeneration

Age-related macular degeneration (AMD) is the most common form of visual impairment, in people over 65, in the Western world. AMD is a multifactorial disease with genetic and environmental factors influencing disease progression. Cigarette smoking is the most significant environmental influence with an estimated increase in risk of 2- to 4-fold. Smoke-induced damage in AMD is mediated through direct oxidation, depletion of antioxidant protection, immune system activation and atherosclerotic vascular changes. Moreover, cigarette smoke induces angiogenesis promoting choroidal neovascularisation and progression to neovascular AMD. Further investigation into the effects of cigarette smoke through in vitro and in vivo experimentation will provide a greater insight into the pathogenesis of age-related macular degeneration.

Smoking, clopidogrel, and mortality in patients with established cardiovascular disease

BACKGROUND

Smoking increases platelet aggregability and the degree of platelet inhibition by clopidogrel on ex vivo platelet function tests. Whether smoking status affects the relationship between clopidogrel and clinical outcomes is unknown.

METHODS AND RESULTS

We evaluated the relationship between smoking status (current smoker, former smoker, or never-smoker) and treatment with clopidogrel on the risk of all-cause, cardiovascular, and cancer mortality among the 12 152 participants from the CHARISMA (Clopidogrel for High Atherothrombotic Risk and Ischemic Stabilization, Management, and Avoidance) trial who had established cardiovascular disease. Current smoking was associated with an increase in all-cause (adjusted hazard ratio [HR] 2.58, 95% confidence interval [CI] 1.85 to 3.60), cardiovascular (HR 2.26, 95% CI 1.48 to 3.45), and cancer (HR 3.56, 95% CI 1.96 to 6.46) mortality compared with never smoking. The impact of clopidogrel on mortality differed by smoking status (P for interaction=0.018 for current smokers). Among current smokers, clopidogrel was associated with a reduction in all-cause mortality (HR 0.68, 95% CI 0.49 to 0.94); clopidogrel did not reduce all-cause mortality among former smokers (HR 0.95, 95% CI 0.75 to 1.19) or never-smokers (HR 1.14, 95% CI 0.83 to 1.58). A similar pattern was noted for cardiovascular mortality. As expected, no relationship was observed between clopidogrel and cancer mortality by smoking status. The risk of bleeding appeared to differ according to smoking status; randomized clopidogrel was associated with a significantly increased risk of severe or moderate bleeding (HR 1.62, P=0.04) among current smokers but a smaller and nonsignificant increase among never-smokers (HR 1.31, P=0.15).

CONCLUSIONS

Clopidogrel therapy may be more effective in current smokers, but it may also confer a greater bleeding risk than in nonsmokers. Further studies are needed to investigate this possibility.