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European Urology Aug 2023Bladder cancer (BC) is common worldwide and poses a significant public health challenge. External risk factors and the wider exposome (totality of exposure from external... (Review)
Review
CONTEXT
Bladder cancer (BC) is common worldwide and poses a significant public health challenge. External risk factors and the wider exposome (totality of exposure from external and internal factors) contribute significantly to the development of BC. Therefore, establishing a clear understanding of these risk factors is the key to prevention.
OBJECTIVE
To perform an up-to-date systematic review of BC's epidemiology and external risk factors.
EVIDENCE ACQUISITION
Two reviewers (I.J. and S.O.) performed a systematic review using PubMed and Embase in January 2022 and updated it in September 2022. The search was restricted to 4 yr since our previous review in 2018.
EVIDENCE SYNTHESIS
Our search identified 5177 articles and a total of 349 full-text manuscripts. GLOBOCAN data from 2020 revealed an incidence of 573 000 new BC cases and 213 000 deaths worldwide in 2020. The 5-yr prevalence worldwide in 2020 was 1 721 000. Tobacco smoking and occupational exposures (aromatic amines and polycyclic aromatic hydrocarbons) are the most substantial risk factors. In addition, correlative evidence exists for several risk factors, including specific dietary factors, imbalanced microbiome, gene-environment risk factor interactions, diesel exhaust emission exposure, and pelvic radiotherapy.
CONCLUSIONS
We present a contemporary overview of the epidemiology of BC and the current evidence for BC risk factors. Smoking and specific occupational exposures are the most established risk factors. There is emerging evidence for specific dietary factors, imbalanced microbiome, gene-external risk factor interactions, diesel exhaust emission exposure, and pelvic radiotherapy. Further high-quality evidence is required to confirm initial findings and further understand cancer prevention.
PATIENT SUMMARY
Bladder cancer is common, and the most substantial risk factors are smoking and workplace exposure to suspected carcinogens. On-going research to identify avoidable risk factors could reduce the number of people who get bladder cancer.
Topics: Humans; Vehicle Emissions; Risk Factors; Urinary Bladder Neoplasms; Smoking; Tobacco Smoking; Occupational Exposure
PubMed: 37198015
DOI: 10.1016/j.eururo.2023.03.029 -
EBioMedicine Aug 2022The causal association between cigarette smoking and several diseases remains equivocal. The purpose of this study was to appraise the causal role of smoking in a wide... (Meta-Analysis)
Meta-Analysis
BACKGROUND
The causal association between cigarette smoking and several diseases remains equivocal. The purpose of this study was to appraise the causal role of smoking in a wide range of diseases by summarizing the evidence from Mendelian randomization (MR) studies.
METHODS
MR studies on genetic liability to smoking initiation or lifetime smoking (composite of smoking initiation, heaviness, duration, and cessation) in relation to circulatory system, digestive system, nervous system, musculoskeletal system, endocrine, metabolic, and eye diseases, and neoplasms published until February 15, 2022, were identified in PubMed. De novo MR analyses were performed using summary statistics data from genome-wide association studies. Meta-analysis was applied to combine study-specific estimates.
FINDINGS
Meta-analyses of findings of 29 published MR studies and 123 de novo MR analyses of 57 distinct primary outcomes showed that genetic liability to smoking (smoking initiation or lifetime smoking) was associated with increased risk of 13 circulatory system diseases, several digestive system diseases (including diverticular, gallstone, gastroesophageal reflux, and Crohn's disease, acute pancreatitis, and periodontitis), epilepsy, certain musculoskeletal system diseases (including fracture, osteoarthritis, and rheumatoid arthritis), endocrine (polycystic ovary syndrome), metabolic (type 2 diabetes) and eye diseases (including age-related macular degeneration and senile cataract) as well as cancers of the lung, head and neck, esophagus, pancreas, bladder, kidney, cervix, and ovaries, and myeloid leukemia. Smoking liability was associated with decreased risk of Parkinson's disease and prostate cancer.
INTERPRETATION
This study found robust evidence that cigarette smoking causes a wide range of diseases.
FUNDING
This work was supported by research grants from the Swedish Cancer Society (Cancerfonden), the Swedish Heart Lung Foundation (Hjärt-Lungfonden, 20210351), the Swedish Research Council for Health, Working Life and Welfare (Forte, 2018-00123), and the Swedish Research Council (Vetenskapsrådet, 2019-00977). Stephen Burgess is supported by Sir Henry Dale Fellowship jointly funded by the Wellcome Trust and the Royal Society (204623/Z/16/Z) and the National Institute for Health Research Cambridge Biomedical Research Centre (BRC-1215-20014). The views expressed are those of the authors and not necessarily those of the National Institute for Health Research or the Department of Health and Social Care.
Topics: Acute Disease; Diabetes Mellitus, Type 2; Female; Genome-Wide Association Study; Humans; Male; Mendelian Randomization Analysis; Neoplasms; Pancreatitis; Polymorphism, Single Nucleotide; Smoking
PubMed: 35816897
DOI: 10.1016/j.ebiom.2022.104154 -
Medicina (Kaunas, Lithuania) Dec 2021: Tobacco is today the single most preventable cause of death, being associated with countless diseases, including cancer and neurological, cardiovascular, and... (Meta-Analysis)
Meta-Analysis Review
: Tobacco is today the single most preventable cause of death, being associated with countless diseases, including cancer and neurological, cardiovascular, and respiratory diseases. Smoking also brings negative consequences to oral health, potentially impairing treatment with dental implants. The present review aimed to evaluate the influence of smoking on dental implant failure rates and marginal bone loss (MBL). : Electronic search was undertaken in three databases, plus a manual search of journals. Meta-analyses were performed, in addition to meta-regressions, in order to verify how the odds ratio (OR) and MBL were associated with follow-up time. : The review included 292 publications. Altogether, there were 35,511 and 114,597 implants placed in smokers and in non-smokers, respectively. Pairwise meta-analysis showed that implants in smokers had a higher failure risk in comparison with non-smokers (OR 2.402, < 0.001). The difference in implant failure between the groups was statistically significant in the maxilla (OR 2.910, < 0.001), as well as in the mandible (OR 2.866, < 0.001). The MBL mean difference (MD) between the groups was 0.580 mm ( < 0.001). There was an estimated decrease of 0.001 in OR ( = 0.566) and increase of 0.004 mm ( = 0.279) in the MBL MD between groups for every additional month of follow-up, although without statistical significance. Therefore, there was no clear influence of the follow-up on the effect size (OR) and on MBL MD between groups. : Implants placed in smokers present a 140.2% higher risk of failure than implants placed in non-smokers.
Topics: Dental Implants; Humans; Mandible; Maxilla; Smokers; Smoking
PubMed: 35056347
DOI: 10.3390/medicina58010039 -
Nicotine & Tobacco Research : Official... Jan 2017Many studies report a positive association between smoking and mental illness. However, the literature remains mixed regarding the direction of this association. We... (Review)
Review
BACKGROUND
Many studies report a positive association between smoking and mental illness. However, the literature remains mixed regarding the direction of this association. We therefore conducted a systematic review evaluating the association of smoking and depression and/or anxiety in longitudinal studies.
METHODS
Studies were identified by searching PubMed, Scopus, and Web of Science and were included if they: (1) used human participants, (2) were longitudinal, (3) reported primary data, (4) had smoking as an exposure and depression and/or anxiety as an outcome, or (5) had depression and/or anxiety as the exposure and smoking as an outcome.
RESULTS
Outcomes from 148 studies were categorized into: smoking onset, smoking status, smoking heaviness, tobacco dependence, and smoking trajectory. The results for each category varied substantially, with evidence for positive associations in both directions (smoking to later mental health and mental health to later smoking) as well as null findings. Overall, nearly half the studies reported that baseline depression/anxiety was associated with some type of later smoking behavior, while over a third found evidence that a smoking exposure was associated with later depression/anxiety. However, there were few studies directly supporting a bidirectional model of smoking and anxiety, and very few studies reporting null results.
CONCLUSIONS
The literature on the prospective association between smoking and depression and anxiety is inconsistent in terms of the direction of association most strongly supported. This suggests the need for future studies that employ different methodologies, such as Mendelian randomization (MR), which will allow us to draw stronger causal inferences.
IMPLICATIONS
We systematically reviewed longitudinal studies on the association of different aspects of smoking behavior with depression and anxiety. The results varied considerably, with evidence for smoking both associated with subsequent depression and anxiety, and vice versa. Few studies supported a bidirectional relationship, or reported null results, and no clear patterns by gender, ethnicity, clinical status, length to follow-up, or diagnostic test. Suggesting that despite advantages of longitudinal studies, they cannot alone provide strong evidence of causality. Therefore, future studies investigating this association should employ different methods allowing for stronger causal inferences to be made, such as MR.
Topics: Anxiety; Anxiety Disorders; Depression; Depressive Disorder; Humans; Prospective Studies; Sex Characteristics; Smoking; Tobacco Use Disorder
PubMed: 27199385
DOI: 10.1093/ntr/ntw140 -
JAMA Pediatrics Aug 2017The public health implications of e-cigarettes depend, in part, on whether e-cigarette use affects the risk of cigarette smoking. (Meta-Analysis)
Meta-Analysis Review
IMPORTANCE
The public health implications of e-cigarettes depend, in part, on whether e-cigarette use affects the risk of cigarette smoking.
OBJECTIVE
To perform a systematic review and meta-analysis of longitudinal studies that assessed initial use of e-cigarettes and subsequent cigarette smoking.
DATA SOURCES
PubMed, EMBASE, Cochrane Library, Web of Science, the 2016 Society for Research on Nicotine and Tobacco 22nd Annual Meeting abstracts, the 2016 Society of Behavioral Medicine 37th Annual Meeting & Scientific Sessions abstracts, and the 2016 National Institutes of Health Tobacco Regulatory Science Program Conference were searched between February 7 and February 17, 2017. The search included indexed terms and text words to capture concepts associated with e-cigarettes and traditional cigarettes in articles published from database inception to the date of the search.
STUDY SELECTION
Longitudinal studies reporting odds ratios for cigarette smoking initiation associated with ever use of e-cigarettes or past 30-day cigarette smoking associated with past 30-day e-cigarette use. Searches yielded 6959 unique studies, of which 9 met inclusion criteria (comprising 17 389 adolescents and young adults).
DATA EXTRACTION AND SYNTHESIS
Study quality and risk of bias were assessed using the Newcastle-Ottawa Scale and the Risk of Bias in Non-randomized Studies of Interventions tool, respectively. Data and estimates were pooled using random-effects meta-analysis.
MAIN OUTCOMES AND MEASURES
Among baseline never cigarette smokers, cigarette smoking initiation between baseline and follow-up. Among baseline non-past 30-day cigarette smokers who were past 30-day e-cigarette users, past 30-day cigarette smoking at follow-up.
RESULTS
Among 17 389 adolescents and young adults, the ages ranged between 14 and 30 years at baseline, and 56.0% were female. The pooled probabilities of cigarette smoking initiation were 30.4% for baseline ever e-cigarette users and 7.9% for baseline never e-cigarette users. The pooled probabilities of past 30-day cigarette smoking at follow-up were 21.5% for baseline past 30-day e-cigarette users and 4.6% for baseline non-past 30-day e-cigarette users. Adjusting for known demographic, psychosocial, and behavioral risk factors for cigarette smoking, the pooled odds ratio for subsequent cigarette smoking initiation was 3.62 (95% CI, 2.42-5.41) for ever vs never e-cigarette users, and the pooled odds ratio for past 30-day cigarette smoking at follow-up was 4.28 (95% CI, 2.52-7.27) for past 30-day e-cigarette vs non-past 30-day e-cigarette users at baseline. A moderate level of heterogeneity was observed among studies (I2 = 60.1%).
CONCLUSIONS AND RELEVANCE
e-Cigarette use was associated with greater risk for subsequent cigarette smoking initiation and past 30-day cigarette smoking. Strong e-cigarette regulation could potentially curb use among youth and possibly limit the future population-level burden of cigarette smoking.
Topics: Adolescent; Adolescent Behavior; Disease Progression; Electronic Nicotine Delivery Systems; Female; Humans; Male; Risk Factors; Smoking; Smoking Cessation; Tobacco Use Disorder; Young Adult
PubMed: 28654986
DOI: 10.1001/jamapediatrics.2017.1488 -
American Journal of Preventive Medicine Jun 2018The study systematically reviewed articles on the association between tobacco smoking and periodontitis, as it has been hypothesized that smoking affects the course of... (Meta-Analysis)
Meta-Analysis
CONTEXT
The study systematically reviewed articles on the association between tobacco smoking and periodontitis, as it has been hypothesized that smoking affects the course of periodontitis through impairment of immunological and vascular mechanisms.
EVIDENCE ACQUISITION
Searches of articles indexed in PubMed, Scopus, and Embase were performed up to and including May 2017. Search strategy included MeSH and free terms: periodontitis, periodontal diseases, smoking, tobacco use, tobacco, tobacco products, cigarette, pipe, and cigar. Only original prospective longitudinal studies that investigated the association between smoking and periodontitis incidence or progression were included. Results were shown as combined risk ratio. Meta-regression and subgroup analyses were used to explore potential sources of heterogeneity. Analyses were conducted in August 2017.
EVIDENCE SYNTHESIS
Twenty-eight studies were included in the review; of these, only 14 presented data that could be included in the meta-analysis. Pooled adjusted risk ratios estimate that smoking increases the risk of periodontitis by 85% (risk ratio=1.85, 95% CI=1.5, 2.2). Meta-regression demonstrated that age explained 54.2% of the variability between studies, time of follow-up explained 13.5%, loss to follow-up 10.7%, criteria used to assess the periodontal status explained 2.1%, and severity of periodontitis explained 16.9%.
CONCLUSIONS
Smoking has a detrimental effect on the incidence and progression of periodontitis. Tobacco smoking, therefore, is important information that should be assessed along with other risk factors for periodontitis.
Topics: Humans; Incidence; Longitudinal Studies; Periodontitis; Prospective Studies; Risk Factors; Smoking; Tobacco Products
PubMed: 29656920
DOI: 10.1016/j.amepre.2018.02.014 -
Clinical Gastroenterology and... Feb 2016Gastroesophageal reflux disease (GERD) affects up to 30% of adults in Western populations and is increasing in prevalence. GERD is associated with lifestyle factors,... (Review)
Review
BACKGROUND & AIMS
Gastroesophageal reflux disease (GERD) affects up to 30% of adults in Western populations and is increasing in prevalence. GERD is associated with lifestyle factors, particularly obesity and tobacco smoking, which also threatens the patient's general health. GERD carries the risk of several adverse outcomes and there is widespread use of potent acid-inhibitors, which are associated with long-term adverse effects. The aim of this systematic review was to assess the role of lifestyle intervention in the treatment of GERD.
METHODS
Literature searches were performed in PubMed (from 1946), EMBASE (from 1980), and the Cochrane Library (no start date) to October 1, 2014. Meta-analyses, systematic reviews, randomized clinical trials (RCTs), and prospective observational studies were included.
RESULTS
Weight loss was followed by decreased time with esophageal acid exposure in 2 RCTs (from 5.6% to 3.7% and from 8.0% to 5.5%), and reduced reflux symptoms in prospective observational studies. Tobacco smoking cessation reduced reflux symptoms in normal-weight individuals in a large prospective cohort study (odds ratio, 5.67). In RCTs, late evening meals increased time with supine acid exposure compared with early meals (5.2% point change), and head-of-the-bed elevation decreased time with supine acid exposure compared with a flat position (from 21% to 15%).
CONCLUSIONS
Weight loss and tobacco smoking cessation should be recommended to GERD patients who are obese and smoke, respectively. Avoiding late evening meals and head-of-the-bed elevation is effective in nocturnal GERD.
Topics: Behavior Therapy; Gastroesophageal Reflux; Humans; Life Style; Obesity; Prospective Studies; Smoking
PubMed: 25956834
DOI: 10.1016/j.cgh.2015.04.176 -
Clinical and Experimental Dental... Jun 2021While tobacco cigarette smoking has been proven to be a risk factor for periodontitis, limited information is available regarding vaping, a new alternative to smoking... (Review)
Review
BACKGROUND AND OBJECTIVE
While tobacco cigarette smoking has been proven to be a risk factor for periodontitis, limited information is available regarding vaping, a new alternative to smoking that has been branded as less harmful. Several important in vitro studies have shown that vaping has a similarly damaging effect as cigarette smoking on the health of the periodontium. However, a comprehensive review is lacking in this field. Therefore, we aimed to systematically review the literature about the impact of vaping on periodontitis.
METHODS
The research question was created using the PICOs format. A systematic search of the following electronic databases was performed up to March 2020: Medline, Embase, PubMed, Cochrane, and grey literature. Human studies that assessed periodontal status (plaque index, bleeding on probing, clinical attachment loss, marginal bone loss, and probing depth) in e-cigarette users compared to non-smokers (control group) were assessed based on an estimate of fixed effects. The weights of the studies were calculated based on their risks of bias.
RESULTS
After duplicates were removed, 1,659 studies were screened and 8 case-control studies that investigated the relationship between vaping and periodontal parameters in humans were selected after their risk of bias assessment. Estimated effects of vaping after weighting results based on their standard deviation showed increased plaque, marginal bone loss, clinical attachment loss, pocket depth, and reduced bleeding on probing.
CONCLUSION
This study concluded that there is not enough evidence to fully characterize the impacts of vaping on periodontitis. However, within the limitations of our review and the selected included studies, the available results point to increased destruction of the periodontium leading to the development of the disease.
Topics: Electronic Nicotine Delivery Systems; Humans; Periodontitis; Smokers; Smoking; Vaping
PubMed: 33274850
DOI: 10.1002/cre2.360 -
The Lancet. Respiratory Medicine Feb 2016Smokers increasingly use e-cigarettes for many reasons, including attempts to quit combustible cigarettes and to use nicotine where smoking is prohibited. We aimed to... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Smokers increasingly use e-cigarettes for many reasons, including attempts to quit combustible cigarettes and to use nicotine where smoking is prohibited. We aimed to assess the association between e-cigarette use and cigarette smoking cessation among adult cigarette smokers, irrespective of their motivation for using e-cigarettes.
METHODS
PubMed and Web of Science were searched between April 27, 2015, and June 17, 2015. Data extracted included study location, design, population, definition and prevalence of e-cigarette use, comparison group (if applicable), cigarette consumption, level of nicotine dependence, other confounders, definition of quitting smoking, and odds of quitting smoking. The primary endpoint was cigarette smoking cessation. Odds of smoking cessation among smokers using e-cigarettes compared with smokers not using e-cigarettes were assessed using a random effects meta-analysis. A modification of the ACROBAT-NRSI tool and the Cochrane Risk of Bias Tool were used to assess bias. This meta-analysis is registered with PROSPERO (number CRD42015020382).
FINDINGS
38 studies (of 577 studies identified) were included in the systematic review; all 20 studies with control groups (15 cohort studies, three cross-sectional studies, and two clinical trials) were included in random effects meta-analysis and sensitivity analyses. Odds of quitting cigarettes were 28% lower in those who used e-cigarettes compared with those who did not use e-cigarettes (odds ratio [OR] 0·72, 95% CI 0·57-0·91). Association of e-cigarette use with quitting did not significantly differ among studies of all smokers using e-cigarettes (irrespective of interest in quitting cigarettes) compared with studies of only smokers interested in cigarette cessation (OR 0·63, 95% CI 0·45-0·86 vs 0·86, 0·60-1·23; p=0·94). Other study characteristics (design, population, comparison group, control variables, time of exposure assessment, biochemical verification of abstinence, and definition of e-cigarette use) were also not associated with the overall effect size (p≥0·77 in all cases).
INTERPRETATION
As currently being used, e-cigarettes are associated with significantly less quitting among smokers.
FUNDING
National Institutes of Health, National Cancer Institute, FDA Center for Tobacco Products.
Topics: Electronic Nicotine Delivery Systems; Humans; Motivation; Odds Ratio; Prevalence; Smoking; Smoking Cessation
PubMed: 26776875
DOI: 10.1016/S2213-2600(15)00521-4 -
The Cochrane Database of Systematic... Mar 2017Individual counselling from a smoking cessation specialist may help smokers to make a successful attempt to stop smoking. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Individual counselling from a smoking cessation specialist may help smokers to make a successful attempt to stop smoking.
OBJECTIVES
The review addresses the following hypotheses:1. Individual counselling is more effective than no treatment or brief advice in promoting smoking cessation.2. Individual counselling is more effective than self-help materials in promoting smoking cessation.3. A more intensive counselling intervention is more effective than a less intensive intervention.
SEARCH METHODS
We searched the Cochrane Tobacco Addiction Group Specialized Register for studies with counsel* in any field in May 2016.
SELECTION CRITERIA
Randomized or quasi-randomized trials with at least one treatment arm consisting of face-to-face individual counselling from a healthcare worker not involved in routine clinical care. The outcome was smoking cessation at follow-up at least six months after the start of counselling.
DATA COLLECTION AND ANALYSIS
Both authors extracted data in duplicate. We recorded characteristics of the intervention and the target population, method of randomization and completeness of follow-up. We used the most rigorous definition of abstinence in each trial, and biochemically-validated rates where available. In analysis, we assumed that participants lost to follow-up continued to smoke. We expressed effects as a risk ratio (RR) for cessation. Where possible, we performed meta-analysis using a fixed-effect (Mantel-Haenszel) model. We assessed the quality of evidence within each study using the Cochrane 'Risk of bias' tool and the GRADE approach.
MAIN RESULTS
We identified 49 trials with around 19,000 participants. Thirty-three trials compared individual counselling to a minimal behavioural intervention. There was high-quality evidence that individual counselling was more effective than a minimal contact control (brief advice, usual care, or provision of self-help materials) when pharmacotherapy was not offered to any participants (RR 1.57, 95% confidence interval (CI) 1.40 to 1.77; 27 studies, 11,100 participants; I = 50%). There was moderate-quality evidence (downgraded due to imprecision) of a benefit of counselling when all participants received pharmacotherapy (nicotine replacement therapy) (RR 1.24, 95% CI 1.01 to 1.51; 6 studies, 2662 participants; I = 0%). There was moderate-quality evidence (downgraded due to imprecision) for a small benefit of more intensive counselling compared to brief counselling (RR 1.29, 95% CI 1.09 to 1.53; 11 studies, 2920 participants; I = 48%). None of the five other trials that compared different counselling models of similar intensity detected significant differences.
AUTHORS' CONCLUSIONS
There is high-quality evidence that individually-delivered smoking cessation counselling can assist smokers to quit. There is moderate-quality evidence of a smaller relative benefit when counselling is used in addition to pharmacotherapy, and of more intensive counselling compared to a brief counselling intervention.
Topics: Behavior Therapy; Counseling; Humans; Psychotherapy, Group; Randomized Controlled Trials as Topic; Self-Help Groups; Smoking; Smoking Cessation; Smoking Prevention; Tobacco Use Cessation Devices
PubMed: 28361496
DOI: 10.1002/14651858.CD001292.pub3