Evidence relating cigarettes,cigars and pipes to cardiovascular disease and stroke:Meta-analysis of recent data from three regions

BACKGROUND More recent data are required relating to disease risk for use of various smoked products and of other products containing nicotine.Earlier we published metaanalyses of recent results for chronic obstructive pulmonary disease and lung cancer on the relative risk(RR)of current compared to never product use for cigarettes,cigars and pipes based on evidence from North America,Europe and Japan.We now report corresponding up-to-date evidence for acute myocardial infarction(AMI),ischaemic heart disease(IHD)and stroke.AIM To estimate,using recent data,AMI,IHD and stroke RRs by region for current smoking of cigarettes,cigars and pipes.METHODS Publications in English from 2015 to 2020 were considered that,based on epidemiological studies in the three regions,estimated the current smoking RR of AMI,IHD or stroke for one or more of the three products.The studies should involve at least 100 cases of stroke or cardiovascular disease(CVD),not be restricted to populations with specific medical conditions,and should be of cohort or nested case-control study design or randomized controlled trials.A literature search was conducted on MEDLINE,examining titles and abstracts initially,and then full texts.Additional papers were sought from reference lists of selected papers,reviews and meta-analyses.For each study identified,we entered the most recent available data on current smoking of each product,as well as the characteristics of the study and the RR estimates.Combined RR estimates were derived using random-effects meta-analysis for stroke and,in the case of CVD,separately for IHD and AMI.For cigarette smoking,where far more data were available,heterogeneity was studied by a wide range of factors.For cigar and pipe smoking,a more limited heterogeneity analysis was carried out.A more limited assessment of variation in risk by daily number of cigarettes smoked was also conducted.RESULTS Current cigarette smoking:Ten studies gave a random-effects RR for AMI of 2.72[95%confidence interval(CI):2.40-3.08],derived from 13 estimates between 1.47 and 4.72.Twenty-three studies gave an IHD RR of 2.01(95%CI:1.84-2.21),using 28 estimates between 0.81 and 4.30.Thirty-one studies gave a stroke RR of 1.62(95%CI:1.48-1.77),using 37 estimates from 0.66 to 2.91.Though heterogeneous,only two of the overall 78 RRs were below 1.0,71 significantly(P<0.05)exceeding 1.0.The heterogeneity was only partly explicable by the factors studied.Estimates were generally higher for females and for later-starting studies.They were significantly higher for North America than Europe for AMI,but not the other diseases.For stroke,the only endpoint with multiple Japanese studies,RRs were lower there than for Western studies.Adjustment for multiple factors tended to increase RRs.Our RR estimates and the variations by sex and region are consistent with earlier meta-analyses.RRs generally increased with amount smoked.Current cigar and pipe smoking:No AMI data were available.One North American study reported reduced IHD risk for non-exclusive cigar or pipe smoking,but considered few cases.Two North American studies found no increased stroke risk with exclusive cigar smoking,one reporting reduced risk for exclusive pipe smoking(RR 0.24,95%CI:0.06-0.91).The cigar results agree with an earlier review showing no clear risk increase for IHD or stroke.CONCLUSION Current cigarette smoking increases risk of AMI,IHD and stroke,RRs being 2.72,2.01 and 1.62.The stroke risk is lower in Japan,no increase was seen for cigars/pipes.

Inhibition of the NF-κB Signaling Pathway Improves Cigarette Mainstream Smoke-Induced Lung Injury and Gut Microbiota Disturbance

Currently,cigarette smoke(CS)remains a major contributor to disease morbidity and mortality.CS can be divided into cigarette mainstream smoke(CMS)and side-stream smoke,depending on where it is produced by burning tobacco^([1]).CMS is inhaled by smokers from the filter end during cigarette combustion and is strongly associated with the development of several diseases^([2-4]).

Unveiling the dynamic role of innate and adaptive immune cells in COPD pathogenesis induced by cigarette smoke

Chronic obstructive pulmonary disease(COPD)is a multifaceted syndrome characterized by a dysregulated inflammatory cascade within the respiratory system,primarily triggered by exposure to harmful particles and gases,notably from cigarette smoke.This inflammatory response is orchestrated by innate immune cells like macrophages and epithelial cells,which recognize danger signals released from damaged cells.Prolonged inflammation prompts an adaptive immune reaction mediated by dendritic cells,culminating in the formation of lymphoid follicles and involving a complex interplay of T and B cells,as well as cytotoxic activity.Additionally,both viral and bacterial infections exacerbate COPD by further igniting inflammatory pathways,perpetuating the chronic inflammatory state.This comprehensive review encapsulates the intricate interplay between innate and adaptive immunity in COPD,with a particular focus on the role of cigarette smoke in its pathogenesis and potential therapeutic targets.

Research on the Relationship Between Average Cigarette Price per Box and Government Procurement in City A Based on a Regression Model

This study aims to analyze and predict the relationship between the average price per box in the cigarette market of City A and government procurement,providing a scientific basis and support for decision-making.By reviewing relevant theories and literature,qualitative prediction methods,regression prediction models,and other related theories were explored.Through the analysis of annual cigarette sales data and government procurement data in City A,a comprehensive understanding of the development of the tobacco industry and the economic trends of tobacco companies in the county was obtained.By predicting and analyzing the average price per box of cigarette sales across different years,corresponding prediction results were derived and compared with actual sales data.The prediction results indicate that the correlation coefficient between the average price per box of cigarette sales and government procurement is 0.982,implying that government procurement accounts for 96.4%of the changes in the average price per box of cigarettes.These findings offer an in-depth exploration of the relationship between the average price per box of cigarettes in City A and government procurement,providing a scientific foundation for corporate decision-making and market operations.

Analysis of four tobacco-specific nitrosamines in mainstream cigarette smoke of Virginia cigarettes by LC-MS/MS

An improved method was developed for the determination of the four major tobacco-specific nitrosamines（TSNAs） in mainstream cigarette smoke. The new method offers decreased sample preparation and analysis time as compared to traditional methods. This method uses isotope dilution liquid chromatography coupled with a tandem mass spectrometer with electrospray ionization and is significantly more sensitive than traditional methods. It also shows no evidence of artifactual formation of TSNAs. Sample concentrations were determined for four TSNAs in mainstream smoke using two isotopically labeled TSNAs analogues as internal standards. Mainstream smoke was collected on an industry standard 44-ram Cambridge filter pad, extracted with 0.1 mol/L ammonium acetate, purified by solid-phase extraction, and analyzed without further sample cleanup. The analytical column is a 3.9 mm×150 mm Waters Symmertry Shield RP18 column and volume fraction of the mobile phase is 50% methanol, 50% water containing 0.1% acetic acid. The results show that the linear range is 0.5-100.0 mg/L except for N-nitrosoanabasine （NAB） from 0.25 to 50.0 mg/L. The limits of detection are 0.1 mg/L for N-nitrosonornicotine （NNN）, 0.08 mg/L for 4-（methylnitrosamino）-1- （3-py-ridyl）-1-butanone （NNK）, 0.05 mg/L for N-nitrosoanatabine （NAT） and 0.06 mg/L for NAB. The recoveries of the four TSNAs are from 90.2% to 105.7%.

The Impact of Tobacco Taxation Policy on Slim Cigarette Use and the Growing Popularity of Slim Cigarettes in China Since 2014

Introduction: In 2016, China became the largest market for slim cigarettes in the world, selling 68.945 billion sticks. The purpose of this study is to examine the impact of China’s 2015 tobacco taxation policy on slim cigarette consumption and the product’s market trends. Methods: Monthly data on the market share of slim cigarettes and their average price between January 2014 and June 2017 were used to show tobacco market trends and to estimate the impact of the 2015 tobacco tax increase on tobacco consumption. Segmented regression analysis was used to estimate the immediate effect of the 2015 tax policy and the time trends in consumption due to the policy change. Findings: After the tobacco tax increase was announced in May 2015, the market share of slim cigarettes initially decreased by 0.2117 (p = 0.067). However, by the third month after the policy change, consumption began to increase, and the market share of slim cigarettes was 1.6 times the normal increase over time. Slim cigarettes gained a 2.02% additional share by the second quarter of 2017 (from 2.58% to 4.60%), controlling for the price difference between slim cigarettes and regular cigarettes. The coefficient of the share and the price ratio (slim cigarettes/regular cigarettes) was ?0.7536 (p = 0.0044), suggesting that slim cigarettes are a substitute for regular cigarettes. Estimates also show that after the tax increase was implemented, consumption of slim cigarettes increased almost three times the normal consumption rate (0.0069 versus 0.0024). Conclusion: The slim cigarette industry in China has grown rapidly in recent years. The 2015 tax increase has had only minimal or short-term impact on reducing the growing popularity of slim cigarettes. Since slim cigarettes are a substitute for regular cigarettes, more empirical research is urgently needed to study the health impacts of slim cigarette use and the impact of tobacco control policies on slim cigarette consumption.

Assessment of tobacco heating system 2.4 on osteogenic differentiation of mesenchymal stem cells and primary human osteoblasts compared to conventional cigarettes

BACKGROUND Cigarette smoking(CS)is the most common method of consuming tobacco.Deleterious effects on bone integrity,increased incidence of fractures,and delayed fracture healing are all associated with CS.Over 150 of the 6500 molecular species contained in cigarette smoke and identified as toxic compounds are inhaled by CS and,via the bloodstream,reach the skeletal system.New technologies designed to develop a reduced-risk alternative for smokers are based on electronic nicotine delivery systems,such as e-cigarettes and tobacco heating systems(THS).THS are designed to heat tobacco instead of burning it,thereby reducing the levels of harmful toxic compounds released.AIM To examine the effects of THS on osteoprogenitor cell viability and function compared to conventional CS.METHODS Human immortalized mesenchymal stem cells(n=3)and primary human preosteoblasts isolated from cancellous bone samples from BG Unfall Klinik Tübingen(n=5)were osteogenically differentiated in vitro with aqueous extracts generated from either the THS 2.4“IQOS”or conventional“Marlboro”cigarettes for up to 21 d.Cell viability was analyzed using resazurin conversion assay(mitochondrial activity)and calcein-AM staining(esterase activity).Osteogenic differentiation and bone cell function were evaluated using alkaline phosphatase(AP)activity,while matrix formation was analyzed through alizarin red staining.Primary cilia structure was examined by acetylatedα-tubulin immunofluorescent staining.Free radical production was evaluated with 2’,7’-dichlorofluoresceindiacetate assay.RESULTS Our data clearly show that THS is significantly less toxic to bone cells than CS when analyzed by mitochondrial and esterase activity(P<0.001).No significant differences in cytotoxicity between the diverse flavors of THS were observed.Harmful effects from THS on bone cell function were observed only at very high,non-physiological concentrations.In contrast,extracts from conventional cigarettes significantly reduced the AP activity(by two-fold)and matrix mineralization(four-fold)at low concentrations.Additionally,morphologic analysis of primary cilia revealed no significant changes in the length of the organelle involved in osteogenesis of osteoprogenitor cells,nor in the number of ciliated cells following THS treatment.Assessment of free radical production demonstrated that THS induced significantly less oxidative stress than conventional CS in osteoprogenitor cells.CONCLUSIONTHS was significantly less harmful to osteoprogenitor cells during osteogenesisthan conventional CS. Additional studies are required to confirm whether THS isa better alternative for smokers to improve delays in bone healing followingfracture.

On the Development and Maintenance of Cigarettes Exported to North Korea

According to the requirements of " going out" strategy of Jilin Tobacco Industry Co. Ltd.,in order to further expand the Changbaishan series brand in the market of North Korea,this paper elaborates the product development and maintenance ideas and measures for three cigarette companies in North Korea based on the actual work being done,so as to determine the development and maintenance focus of export cigarettes and provide strong technical support for accelerating the pace of localization of production while achieving homogenization of production.

Smoking Cessation with E-Cigarettes in Smokers with a Documented History of Depression and Recurring Relapses

The association between nicotine dependence and affective disorders, particularly major depressive disorder (MDD), is well known with high prevalence rates being reported for smokers. The reason for this association is not clear, but, it has been argued that smoking may help individuals to cope with stress or medicate depressed mood. Smoking cessation programs are useful in helping smokers to quit, but smoking is a very difficult addiction to break, especially for people suffering from depression, and the need for novel and effective approaches to smoking cessation interventions for this special population is unquestionable. The e-cigarette is a battery-powered electronic nicotine delivery device (ENDD), which may help smokers to remain abstinent during their quit attempt. Here, we report for the first time objective measures of smoking cessation in two heavy smokers, suffering from depression, who experimented the e-cigarette.

Toxicology of Commonly Found Ingredients in E-Cigarettes: A Brief Review

Electronic cigarettes (EC) have gained popularity among smokers due to their taste, smell, appearance, and easy availability compared to traditional cigarettes, as well as the perception that they are safer than traditional cigarettes. These devices result in aerosols containing nicotine, propylene glycol, glycerin, ethylene glycol, vitamin E, and chemical flavors inhaled into the lungs. Other components found in these vapors include heavy metals such as nickel, chromium, lead, manganese, and tin. In addition, some ingredients volatilization leads to toxic aldehydes formation such as formaldehyde, acetaldehyde, and acrolein. Smoking cigarettes is addictive and has been associated with many health issues such as heart disease, lung cancer, etc. Rising awareness of these dangers moves more people towards these electronic delivery systems, reducing the health effects of cigarettes. The toxicity of EC’s ingredients is well studied when ingested;however, their toxicity through inhalation remains unclear. Consequently, the use of ECs has become a significant concern worldwide and raises whether it is indeed safe to use. This paper will serve as a literature review paper to discuss the toxicity of commonly found ingredients in ECs and their associated health issues. Our conclusion emphasizes that even though smoking EC is less risker than smoking traditional cigarettes, it is still not safe due to the potentially harmful effect these E-cig’s ingredients have on the human’s health. In addition, E-cigarette’s aerosol could also contain toxic compounds such as formaldehyde, acetaldehyde, and acrolein due to glycerin’s thermo-degradation.

Use of Cigarettes and Other Tobacco Products among Primary and Secondary School Students in Khartoum State, Sudan

Introduction: In Sudan, tobacco use is common;it is used in some form by 20% of the population. As most users start during adolescence, we aimed to determine the prevalence of ever use of tobacco products (i.e. cigarettes, herbal cigarettes, shisha and tombak) among Sudanese adolescent males and females, and to assess associations between tobacco ever use and personal characteristics. Methods: This cross-sectional study was conducted in Khartoum State, Sudan. The study data were collected in June 2014. The target population consisted of adolescents in 8th grade of primary education or 1st and 2nd grade of secondary education. They were asked to fill in a written questionnaire during the school break. Schools were randomly selected using a stratified two-stage cluster sampling design method. Results: A total of 1229 respondents (56.4% male), with a mean age of 14.5 years, were included in the analysis. Prevalence of cigarettes, herbal cigarettes, shisha and tombak ever use were 13%, 7.8% 5.9% and 3.5%, respectively. Older respondents were significantly more likely to have ever smoked cigarettes. Males were found to be significantly more likely to have ever used any tobacco products. Urban adolescents were significantly more likely to have ever used shisha. Respondents were in the bottom third percentiles with regard to academic achievements, had an almost three-fold increased risk of having ever smoked a cigarette and were at least five-fold more likely to have ever smoked herbal cigarettes. Moreover, respondents in the middle third percentiles were more than twice as likely to have ever smoked herbal cigarettes. Conclusion: As uptake of tobacco products increased significantly with age among males with a middle and lower school performance living in urban areas, timely prevention targeting adolescents, such as school-based tobacco control programmes, are recommended. Our findings show that prevention should start in primary school.

Experimental Study on a New Type of Drug-treated Cigarettes Lowering Bronchopulmonary Lesions

A new type of drug-treated cigarettes aimed at low-ering bronchopulmonary lesions have been studied. Therats smoking ordinary cigarettes were compared with therats smoking cigarettes treated with Chinese traditionaldrugs which possessed anti-inflammatory and detoxicationeffects. The results showed that bronchiolar and bronchi-olopulmonary lesions are less in the drug-treated groupby histopathologic observation. We also found that bacte-riophagocytosis and immunocytochemical lysozyme reac-tions of alveolar macrophages in bronchial alveolar lavagefluids from the drug-treated cigarette smoking rats wereweakened. There are some differences of surface ultra-structures of alveolar macrophages between the ordinarysmoking group and the drug-treated smoking group. Thisindicated differentially functional states of these alveo-lar macrophages in the different groups.

A Comparative Study of Non-Volatile Compounds Present in 3R4F Cigarettes and iQOS Heatsticks Utilizing GC-MS

It is now widely suggested that people who are dependent on nicotine should switch from ordinary tobacco smoking to alternative products, which at least reduce the overall harm from smoking. A number of alternatives are now popular, including electronic cigarettes and heatsticks. In this work comparative analysis of the smoke/aerosol emission from 3R4F standard cigarettes and iQOS heatsticks was undertaken. For this, gas chromatography-mass spectrometry (GC-MS) analysis was applied, to measure the non-volatile compounds of smoke/aerosol emission from individual samples, with the specific aim to determine their content of nicotine and selected other main components. All measurement data were collected under the Health Canada Intense (HCI) puffing regime. The most relevant findings of the present investigation can be summarized as follows. First, the number of measured aerosol components in the iQOS samples, with respect to those of 3R4F samples, was significantly lower (notably 37 versus 12 components). Second, the analysis of the iQOS and 3R4F GC-MS chromatographic fingerprints indicated a non-nicotine global component reduction (number and areas excluding nicotine) of larger than 80% for the iQOS samples in comparison to 3R4F samples. Third, the nicotine content of the iQOS aerosol was less than half that contained in the 3R4F smoke. The results from the present investigation indicate that—except for nicotine—smokers are exposed to a largely reduced number and amount of non-volatile, non-nicotine components in the iQOS heatstick aerosol, in comparison to those in the 3R4F cigarette smoke.

Attitudes toward E-Cigarettes, Reasons for Initiating E-Cigarette Use, and Changes in Smoking Behavior after Initiation: A Pilot Longitudinal Study of Regular Cigarette Smokers

Objectives: We examined 1) changes in smoking and vaping behavior and associated cotinine levels and health status among regular smokers who were first-time e-cigarette purchasers and 2) attitudes, intentions, and restrictions regarding e-cigarettes. Methods: We conducted a pilot longitudinal study with assessments of the aforementioned factors and salivary cotinine at weeks 0, 4, and 8. Eligibility criteria included being ≥18 years old, smoking ≥25 of the last 30 days, smoking ≥5 cigarettes per day (cpd), smoking regularly ≥1 year, and not having started using e-cigarettes. Of 72 individuals screened, 40 consented, 36 completed the baseline survey, and 83.3% and 72.2% were retained at weeks 4 and 8, respectively. Results: Participants reduced cigarette consumption from baseline to week 4 and 8 (p’s < 0.001);23.1% reported no cigarette use in the past month at week 8. There was no significant decrease in cotinine from baseline to week 4 or 8 (p’s = ns). At week 8, the majority reported improved health (65.4%), reduced smoker’s cough (57.7%), and improved sense of smell (53.8%) and taste (50.0%). The majority believed that e-cigarettes versus regular cigarettes have fewer health risks (97.2%) and that e-cigarettes have been shown to help smokers quit (80.6%) and reduce cigarette consumption (97.2%). In addition, the majority intended to use e-cigarettes as a complete replacement for regular cigarettes (69.4%) and reported no restriction on e-cigarette use in the home (63.9%) or car (80.6%). Conclusions: Future research is needed to document the long-term impact on smoking behavior and health among cigarette smokers who initiate use of e-cigarettes.

Electronic cigarettes — myocardial infarction, hemodynamic compromise during pregnancy, and systolic and diastolic dysfunction: Minireview

The aim of this study was to review the most recent literature on the safety of electronic cigarettes(ECs)in the context of cardiovascular disease and in the context as a tool for smoking cessation and recreational purposes.The format of this review begins with relevant research from the basic sciences and follows through with a pertinent review of clinical trials.Daily use of ECs has implications in myocardial infarction(MI)with an odds ratio of 1.70 compared to healthy,nonsmokers and even worse risk for MI with dual use of combustible cigarettes together with EC with an odds ratio of 4.62.Studies measuring cardiac function with echocardiography reported both systolic and diastolic dysfunction along with reduced ejection fractions.Platelet aggregation,endothelial function,and hemodynamics during pregnancy were all but some of the pernicious cardiovascular implications of EC exposure.Though more studies need to be done on the topic of EC use and cardiovascular disease,the majority of studies considered in this review concluded some level of harm albeit in some instances less than that of traditional combustible cigarettes.ECs are toxic to human beings and their harmful effects cannot be overlooked.There is some favorable evidence of efficacy in smoking cessation though mixed with concern of chronic EC use.It will take decades to collect data for chronic EC use on long term sequelae,such as lung cancer.Though more and more reports of acute lung injury and hospitalizations related to EC use have been reported.Due to undergoing investigations of possible harm and life threatening complications of EC use,we cannot recommend ECs as safer or a more efficacious method of smoking cessation to traditional nicotine replacement therapies.A notable consideration for much of the literature reviewed are that standardization of EC use is difficult as device generation and battery voltage,frequency of use,and contents of ECliquid are just some of the vast complicating factors that limit the ability to effectively compare data.

Application of Y2O3 nanoparticles on reducing the content of tar in cigarettes

Y2O3 nanoparticles prepared in microemulsion, which were sprayed on cut tobacco, can reduce tar in cigarettes effectively. Reducing the content of tar in many brands of cigarettes was studied. The results show that Y2O3 nanoparticles can reduce tar in cigarettes effectively and have no influence on nicotine when the addition of Y2O3 nanoparticles is 0,5-1.2%. The smaller the grain size of Y2O3 nanoparticles is,the more effective tar reduction is. The principle of reducing tar in cigarettes is studied preliminarily.

The Prevalence, Pattern, and Factors Affecting Cigarette Smoking among Undergraduate Students in a Tertiary Institution in Plateau State, Nigeria

Background: Cigarette smoking is a modern health hazard, and it is preventable. It starts in adolescence for 90% of adults with an average age of onset ranging between 13 - 15 years and is commoner among males. This study is aimed at the prevalence, pattern, and factors affecting Cigarette smoking among undergraduate students in a tertiary institution in Plateau State. Method: A cross-sectional descriptive study involving 290 undergraduate students of the University of Jos was selected using the multistage sampling method. Results: The prevalence of cigarette use was 5.3%. Seven (70.0%) of students smoke daily, 6 (60.0%), smoke cigarettes before Lecture Hours, and 90.0% are unwilling to stop smoking. Smoking was done to experience the highness feeling, 8 (80.0%), peer smoking 8 (80.0%), to reduce stress and tension 5 (50.0%), and Smoking for Fun 7 (70.0%). Most students first smoked a cigarette when with friends 6 (60.0%). Factors significantly associated with the current use of cigarettes among the respondents were religion (χ2 = 4.167, p = 0.041) Level/year of study (χ2 = 32.266, p ≤ 0.001), and type of family (χ2 = 6.271, p = 0.043). Conclusion: Most students smoke daily, smoke before lectures start, and are unwilling to stop smoking. Health-promotion program to help smoking cessation and prevent initiation of smoking is recommended.

Cigarette induced release of exo-miR-34a from 16HBE vesicles targeting CASP2 promoted the proliferation of COPD MRC-5 cell

Objective:To explore how cigarette smoke extract(CES)regulates the expression of exosomal miR-34a in 16 HBE bronchial epithelial cells,thus affecting the proliferation of MRC-5 lung fibroblasts.Methods:CES was prepared from commercially available cigarettes,and 16HBE cells were treated with CES.The exosomal miR-34a collected from Yipeng Ding,Chief Physician,M.D..the supernatant was used for MRC-5 cell culture.The expression level of exosomal miR-34a was detected by RT-PCR.The proliferation ability of MRC-5 cells was determined by CCK-8 cell counting kit.The expression of CASP2 was detected by Western blot,and the target binding of miR-34a and CASP2 gene was verified by dual luciferase.Results:Under the transmission electron microscope,the exosomes in the supernatant of 16 HBE were spherical,with a particle size of about 100 nm;after CES treatment,the expression of exosomal miR-34a significantly increased.Further research showed that the exosomal miR-34a induced by CES can promote the proliferation of MRC-5 cells;miR-34a and CASP2 have a target binding relationship;miR-34a mimic significantly inhibited the expression of CASP2.Conclusion:In CES-induced 16HBE cells,exosomal miR-34a plays a key role in fibroblast proliferation through target binding with the CASP2 gene.

Stubbing Out the Cigarette

China has rolled out laws,policies,and programs to reduce the use of tobacco,and achieved marked results over the past decades.OLD Chen took a drag on his cigarette,watching his three-year-old granddaughter woddle around in a small park in western Beijing.Whenever the toddler came near,he would stretch out his hand holding the cigarette as far away from her as possible.Still,the smell of smoke was perceptible even at arm’s length.“Smoking is no good,my wife complains about it every day,”he acknowledged.“But I am too old to quit,”he said,giving a familiar excuse.Like many men of his generation,the 67-year-old first picked up the nicotine habit from his peers,fellow factory workers in his case.He has noticed that fewer people of his age are smoking today.“Smoking is no good,”he reiterated.

Evidence relating cigarette,cigar and pipe smoking to lung cancer and chronic obstructive pulmonary disease:Meta-analysis of recent data from three regions

BACKGROUND There is a need to have up-to-date information for various diseases on the risk related to the use of different smoked products and the use of other nicotinecontaining products.Here,we contribute to the information pool by presenting up-to-date quantitative evidence for North America,Europe and Japan and for both lung cancer and chronic obstructive pulmonary disease(COPD)on the relative risk(RR)relating to current vs never product use for each of the three smoked tobacco products,cigarettes,cigars and pipes.AIM To estimate lung cancer and COPD current smoking RRs for the three products using recent data for the three regions.METHODS Publications in English from 2010 to 2020 were considered that,based on epidemiological studies in the three regions,estimated the current smoking RR of lung cancer and/or COPD for one or more of the three products.The studies should involve at least 100 cases of the disease considered,not be restricted to specific lung cancer types or populations with specific medical conditions,and should be of cohort or nested case-control study design or randomized controlled trials.Literature searches were conducted on MEDLINE separately for lung cancer and for COPD,examining titles and abstracts initially,and then full texts.Additional papers were sought from reference lists of selected papers,reviews and metaanalyses.For each study identified,the most recent available data on each product were entered on current smoking,as well as on characteristics of the study and the RR estimates.Combined RR estimates were derived using random-effects meta-analysis.For cigarette smoking,where far more data were available,heterogeneity was studied by a wide range of factors.For cigar and pipe smoking,a more limited heterogeneity analysis was carried out.Results were compared with those from previous meta-analyses published since 2000.RESULTS Current cigarette smoking:For lung cancer,44 studies(26 North American,14 European,three Japanese,and one in multiple continents),gave an overall estimate of 12.14[95%confidence interval(CI)10.30-14.30].The estimates were higher(heterogeneity P<0.001)for North American(15.15,CI 12.77-17.96)and European studies(12.30,CI 9.77-15.49)than for Japanese studies(3.61,CI 2.87-4.55),consistent with previous evidence of lower RRs for Asia.RRs were higher(P<0.05)for death(14.85,CI 11.99-18.38)than diagnosis(10.82,CI 8.61-13.60).There was some variation(P<0.05)by study population,with higher RRs for international and regional studies than for national studies and studies of specific populations.RRs were higher in males,as previously reported,the within-study male/female ratio of RRs being 1.52(CI 1.20-1.92).RRs did not vary significantly(P≥0.05)by other factors.For COPD,RR estimates were provided by 18 studies(10 North American,seven European,and one Japanese).The overall estimate of 9.19(CI 6.97-12.13),was based on heterogeneous data(P<0.001),and higher than reported earlier.There was no(P>0.1)variation by sex,region or exclusive use,but limited evidence(0.05<P<0.1)that RR estimates were greater where cases occurring shortly after baseline were ignored;where bronchiectasis was excluded from the COPD definition;and with greater confounder adjustment.Within-study comparisons showed adjusted RRs exceeded unadjusted RRs.Current cigar smoking:Three studies gave an overall lung cancer RR of 2.73(CI 2.36-3.15),with no heterogeneity,lower than the 4.67(CI 3.49-6.25)reported in an earlier review.Only one study gave COPD results,the RR(2.44,CI 0.98-6.05)being imprecise.Current pipe smoking:Four studies gave an overall lung cancer RR of 4.93(CI 1.97-12.32),close to the 5.20(CI 3.50-7.73)given earlier.However,the estimates were heterogeneous,with two above 10,and two below 3.Only one study gave COPD results,the RR(1.12,CI 0.29-4.40),being imprecise.For both diseases,the lower RR estimates for cigars and for pipes than for current smoking of cigarettes aligns with earlier published evidence.CONCLUSION Current cigarette smoking substantially increases lung cancer and COPD risk,more so in North America and Europe than Japan.Limited evidence confirms lower risks for cigars and pipes than cigarettes.