Toxicology of smokeless tobacco: implications for immune, reproductive, and cardiovascular systems

Association of Smokeless Tobacco Use With Perioperative Complications and Revision Surgery After Anterior Cruciate Ligament Reconstruction

BACKGROUND

Tobacco use is a known modifiable risk factor for postoperative complications and revision surgery after anterior cruciate ligament reconstruction (ACLR). Previous studies focus on tobacco as a broad categorization of traditional smoking, smokeless tobacco, and other forms of nicotine use. It is unclear if differences in the type of nicotine used lead to similar adverse outcomes after ACLR.

PURPOSES

To (1) assess the incidence of postoperative complications among ACLR patients who use smokeless tobacco and (2) compare these outcomes with those of patients who do not use tobacco and those who smoke tobacco.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective cohort study utilizing the PearlDiver database was conducted. Patients undergoing primary ACLR with a minimum 2-year follow-up were included. Smokeless tobacco users (n = 898), cigarette smokers (n= 22,062), and non-tobacco users (n= 207,462) were matched based on patient variables and comorbidities. Postoperative complications within 90 days of surgery and subsequent knee surgery within 2 years were compared among groups. Multivariable logistic regressions were used to control for confounding variables.

RESULTS

Compared with nonusers, smokeless tobacco users demonstrated an increased risk of pneumonia (odds ratio [OR], 3.36; 95% CI, 1.41-7.90), acute kidney injury (OR, 12.7; 95% CI, 3.77-52.8), and emergency department (ED) utilization (OR, 6.29; 95% CI, 3.70-10.9) within 90 days of the ACLR. Additionally, smokeless tobacco users had an increased risk of ACLR (OR, 4.75; 95% CI, 3.60-6.26) and meniscal surgery (OR, 2.89; 95% CI, 2.23-3.73) within 2 years. When compared with cigarette smokers, smokeless tobacco users showed an increased risk of pneumonia (OR, 3.25; 95% CI, 1.33-7.78), acute kidney injury (OR, 7.63; 95% CI, 2.72-22.5), and ED visits (OR, 1.55; 95% CI, 1.26-1.90) within 90 days and subsequent ACLR (OR, 4.81; 95% CI, 3.58-6.47) and meniscal surgery (OR, 3.23; 95% CI, 2.45-4.26) within 2 years.

CONCLUSION

Smokeless tobacco use was associated with an increased risk of medical complications, ED utilization, and subsequent procedures compared with nonuser controls and traditional smokers. These findings highlight the importance of considering specific forms of tobacco use in preoperative screening for patients undergoing ACLR.

From cultivation to cancer: formation of N-nitrosamines and other carcinogens in smokeless tobacco and their mutagenic implications

Tobacco use is a major cause of preventable morbidity and mortality globally. Tobacco products, including smokeless tobacco (ST), generally contain tobacco-specific N-nitrosamines (TSNAs), such as N'-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-butanone (NNK), which are potent carcinogens that cause mutations in critical genes in human DNA. This review covers the series of biochemical and chemical transformations, related to TSNAs, leading from tobacco cultivation to cancer initiation. A key aim of this review is to provide a greater understanding of TSNAs: their precursors, the microbial and chemical mechanisms that contribute to their formation in ST, their mutagenicity leading to cancer due to ST use, and potential means of lowering TSNA levels in tobacco products. TSNAs are not present in harvested tobacco but can form due to nitrosating agents reacting with tobacco alkaloids present in tobacco during certain types of curing. TSNAs can also form during or following ST production when certain microorganisms perform nitrate metabolism, with dissimilatory nitrate reductases converting nitrate to nitrite that is then released into tobacco and reacts chemically with tobacco alkaloids. When ST usage occurs, TSNAs are absorbed and metabolized to reactive compounds that form DNA adducts leading to mutations in critical target genes, including the RAS oncogenes and the p53 tumor suppressor gene. DNA repair mechanisms remove most adducts induced by carcinogens, thus preventing many but not all mutations. Lastly, because TSNAs and other agents cause cancer, previously documented strategies for lowering their levels in ST products are discussed, including using tobacco with lower nornicotine levels, pasteurization and other means of eliminating microorganisms, omitting fermentation and fire-curing, refrigerating ST products, and including nitrite scavenging chemicals as ST ingredients.

Altered oral microbiome in Sudanese Toombak smokeless tobacco users carries a newly emerging risk of squamous cell carcinoma development and progression

There are an estimated 6-10 million smokeless tobacco (Toombak) users in Sudan, the majority being males. Toombak is known to be a carcinogenic product that is likely to modify the oral microbiome spatiality into a high-risk potential for the development and progression of oral cancer, but previous studies are lacking in this field. Here, we endeavour for the first time the exploration of the oral microbiome in key mucosal areas of the oral cavity and assess the microbiome variations in premalignant and oral squamous cell carcinoma (OSCC) samples from both users and non-users of Toombak. 16S rRNA sequencing was performed on DNA obtained from pooled saliva, oral mucosa and supragingival plaque from 78 Sudanese users and non-users of Toombak, aged between 20 and 70 years. In 32 of the pooled saliva samples, the mycobiome (fungal) environment was analysed through ITS sequencing. Then, 46 formalin-fixed paraffin-embedded samples of premalignant and OSCC samples were collected, and their associated microbiomes sequenced. The oral Sudanese microbiome was found to be enriched in Streptococcaceae, but Staphylococcaceae were significantly more abundant amongst Toombak users. Genera enriched in the oral cavity of Toombak users included Corynebacterium_1 and Cardiobacterium while in non-users, Prevotella, Lactobacillus and Bifidobacterium were prominent. Aspergillus was the most abundant fungus in the mouths of Toombak users with a marked loss of Candida. The genus Corynebacterium_1 was abundant in the buccal, floor of the mouth and saliva microbiomes as well as in oral cancer samples from Toombak users indicating a possible role for this genus in the early stages of oral cancer development. An oral cancer microbiome that favours poor survival and metastasis in those who use Toombak also emerged that includes the genera Stenotrophomonas and Schlegelella. Those utilising Toombak carry an altered oral microbiome that may be an additional risk factor for this products carcinogenicity to the oral structures. These significant microbiome modulations are a newly emerging key driving factor in oral cancer development and progression in Toombak users while it is also shown that Toombak users carry an oral cancer microbiome that may increase the potential for a poorer prognosis.

An in Vitro Study of Constituents Released from Smokeless Tobacco Products into Human Saliva

Smokeless tobacco (ST) products are used worldwide, and consumption is increasing in the USA. Although ST products are considered to occupy a different position on the tobacco product continuum of risk compared to combusted tobacco products, they can still lead to health problems, including cancer, dental problems and changes in heart rate and blood pressure. Therefore, the determination of harmful and potentially harmful constituents released from ST products into human saliva is important. Four certified reference ST products were tested in this study: loose leaf chewing tobacco (3S1), Swedish-style snus (1S4), snus (1S5) and moist snuff (3S3). These certified reference ST products are manufactured for research purposes, not for human consumption. The reference ST products were used in this study because they have been well characterized and are intended and designed to represent commercial ST products. The reference ST products were incubated in human saliva at 37°C with a range of incubation times for the evaluation of constituents released from these products into human saliva. In this study, alkaloids (nicotine and cotinine), tobacco-specific N-nitrosamines (TSNAs) (N'-nitrosornicotine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone) and benzo[α]pyrene (B[α]P) in the reference ST products and saliva samples were determined by gas chromatography--mass spectrometry (GC--MS), gas chromatography--flame ionization detection (GC--FID), or ultra-performance liquid chromatography--tandem mass spectrometry (UPLC--MS-MS). Our results indicate that the amounts of each constituent released from the reference ST products were altered by the tobacco cut size and product format (pouched or unpouched). The constituents (TSNAs and alkaloids) in moist snuff and loose leaf chewing tobacco were released faster compared to those in Swedish-style snus and snus. B[α]P was only detected in reference moist snuff samples, and only 3.4% of the total B[α]P was released into human saliva after incubation for 60 min, whereas higher percentages of total TSNAs and alkaloids were released at different rates from the four reference ST products.

Toxic effects of smokeless tobacco on female reproductive health: A review

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Smokeless tobacco use can lead to impairments of ovarian function, morphology, oocyte quality and hormonal regulation.

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Use of smokeless tobacco during pregnancy has adverse health effects on both the mother and fetus.

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Exposure to smokeless tobacco in utero has long term health consequences on offspring.

The habitual consumption of tobacco in its various form is widespread and a serious public health issue globally. In particular, the use of smokeless tobacco has increased substantially due to its easy availability and misconception that it is relatively harmless compared to smoking. Tobacco use has been well established from numerous studies as a causative agent of devastating illnesses such as cancer, insulin resistance, hypertension, acute respiratory disease, osteoporosis, etc. Limited but growing evidence have also suggested its role in adversely affecting reproductive capabilities and outcomes in women of reproductive age and during pregnancy. This paper provides an updated review on available literature regarding the negative effects of smokeless tobacco use on female reproductive health, during pregnancy and its adverse consequences on the offspring. Existing data suggests the association between chronic smokeless tobacco use and impairment of ovarian morphology and function, oocyte quality, hormonal perturbations, fetal development and long-term health effects on the fetus. Improved understanding of these issues can contribute to better awareness of the dangers of smokeless tobacco products.

The Potential of Dietary Bioactive Compounds against SARS-CoV-2 and COVID-19-Induced Endothelial Dysfunction

COVID-19 is an endothelial disease. All the major comorbidities that increase the risk for severe SARS-CoV-2 infection and severe COVID-19 including old age, obesity, diabetes, hypertension, respiratory disease, compromised immune system, coronary artery disease or heart failure are associated with dysfunctional endothelium. Genetics and environmental factors (epigenetics) are major risk factors for endothelial dysfunction. Individuals with metabolic syndrome are at increased risk for severe SARS-CoV-2 infection and poor COVID-19 outcomes and higher risk of mortality. Old age is a non-modifiable risk factor. All other risk factors are modifiable. This review also identifies dietary risk factors for endothelial dysfunction. Potential dietary preventions that address endothelial dysfunction and its sequelae may have an important role in preventing SARS-CoV-2 infection severity and are key factors for future research to address. This review presents some dietary bioactives with demonstrated efficacy against dysfunctional endothelial cells. This review also covers dietary bioactives with efficacy against SARS-CoV-2 infection. Dietary bioactive compounds that prevent endothelial dysfunction and its sequelae, especially in the gastrointestinal tract, will result in more effective prevention of SARS-CoV-2 variant infection severity and are key factors for future food research to address.

Tobacco Smoking and Liver Cancer Risk: Potential Avenues for Carcinogenesis

Smoking a cigarette generates over 4000 chemicals that have a deleterious impact on each part of the human body. It produces three main severe effects on the liver organ: oncogenic, immunological, and indirect or direct toxic effects. It results in the production of cytotoxic substances, which raises fibrosis and necro-inflammation. Additionally, it also directs the production of pro-inflammatory cytokines tumour necrosis factor alfa (TNF-α) and interleukins (IL-1β, IL-6) that will be responsible for the chronic liver injury. Furthermore, it gives rise to secondary polycythemia and successively raises the turnover and mass of red cells, which might be a common factor responsible for the development of oxidative stress in the liver due to iron overload. It also produces chemicals that are having oncogenic properties and raises the risk of liver cancer especially in sufferers of chronic hepatitis C. Smoking modulates both humoral and cell-mediated responses by restricting the proliferation of lymphocytes and inducing their apoptosis and ultimately decreasing the surveillance of cancer cells. Moreover, it has been determined that heavy smoking impacts the response of hepatitis C patients to interferon (IFN) therapy through different mechanisms, which can be improved by phlebotomy. Efforts are being made in different nations in decreasing the prevalence of smoking to improve premature death and ill effects of their nation's individuals.

Combustible Cigarette and Smokeless Tobacco Product Preparations Differentially Regulate Intracellular Calcium Mobilization in HL60 Cells

Changes in the level of intracellular calcium ([Ca²⁺]_i) are central to leukocyte signaling and immune response. Although evidence suggests that cigarette smoking affects inflammatory response via an increase in intracellular calcium, it remains unclear if the use of smokeless tobacco (e.g., moist snuff) elicits a similar response. In this study, we evaluated the effects of tobacco product preparations (TPPs), including total particulate matter (TPM) from 3R4F reference cigarettes, smokeless tobacco extract (STE) from 2S3 reference moist snuff, and nicotine alone on Ca²⁺ mobilization in HL60 cells. Treatment with TPM, but not STE or nicotine alone, significantly increased [Ca²⁺]_i in a concentration-dependent manner in HL60 cells. Moreover, TPM-induced [Ca²⁺]_i increase was not related to extracellular Ca²⁺ and did not require the activation of the IP3 pathway nor involved the transient receptor potential (TRP) channels. Our findings indicate that, in cells having either intact or depleted endoplasmic reticulum (ER) Ca²⁺ stores, TPM-mediated [Ca²⁺]_i increase involves cytosolic Ca²⁺ pools other than thapsigargin-sensitive ER Ca²⁺ stores. These results, for the first time, demonstrate that TPM triggers [Ca²⁺]_i increases, while significantly higher nicotine equivalent doses of STE or nicotine alone, did not affect [Ca²⁺]_i under the experimental conditions. In summary, our study suggests that in contrast with STE or nicotine preparations, TPM activates Ca²⁺ signaling pathways in HL60 cells. The differential effect of combustible and non-combustible TPPs on Ca²⁺ mobilization could be a useful in vitro endpoint for tobacco product evaluation.

Arsenic and smokeless tobacco exposure induces DNA damage and oxidative stress in reproductive organs of female Swiss albino mice

Arsenic contamination in the groundwater of Southern Assam, India is well-documented. A specific type of smokeless tobacco (sadagura, SG) is highly prevalent among the local population. Thus, the present study is aimed to evaluate the toxicological implications of arsenic and smokeless tobacco co-exposure on the reproductive health of female mice. The estrous cycle of experimental animals was monitored for 30 days. Histopathological studies and comet assay of ovarian and uterine tissues were performed after 30 days of exposure to SG and arsenic (sodium arsenite, SA). Oxidative stress was estimated biochemically by taking tissue glutathione, lipid peroxidation (LPO), and superoxide dismutase activity as endpoints. Our findings indicated a prolonged diestrus phase in the SG + L + SA group (p < 0.001). Histopathological study revealed abnormal tissue architecture in treated groups. Comet assay study showed that SG + SA exposure significantly induced DNA damage in test animals. The elevated LPO level in the SG + SA group indicated oxidative stress generation in the reproductive tissues. The present study suggests that female reproductive organs are vulnerable to SA and SG and oxidative stress generation may be the possible mechanism behind DNA damage, impaired follicular growth, atresia, and altered estrous cycle in the mice test system.

Quantification of Nicotine and Cotinine in Plasma, Saliva, and Urine by HPLC Method in Chewing Tobacco Users

BACKGROUND

Nicotine acts as major alkaloid of all tobacco products including smokeless tobacco (SLT) forms. The mode of SLT consumption is in the form of chewing under the cheek or lip and induced biochemical alterations in the plasma, saliva, and urine.

MATERIALS AND METHODS

The smokeless tobacco products like Raja or blue bull tobacco brands are widely consumed by human male volunteers under the age of 18-30 years for the period of 3 years consisting of 30g per day. The concentrations of nicotine and cotinine in samples of plasma, saliva, and urine are quantified by the method of HPLC. The remaining variables of plasma are evaluated by auto analyzer and spectrophotometric methods.

RESULTS

The analysis of results presented that significant increase in the levels of nicotine and cotinine in plasma, saliva, and urine of chewing tobacco users. The lipid profile (Cholesterol, triglycerides, HDL-C, and LDL-C), liver marker enzymes (SGOT, SGPT, and ALP), kidney markers (Creatinine, urea, and uric acid), glucose, and the remaining variables are present within normal range observed in SLT users. The lipid peroxidation (LPO), nitric oxide (NO) (NO2 and NO3), protein carbonyls (PCO), and peroxynitrites (ONOO-) are reported to be higher levels in the plasma of experimental subjects in comparison with normal controls. The various brands of tobacco varieties (Raja, madhu chhap, hans chhap, miraj, badshah, blue bull, and swagat gold tobacco) are presented.

CONCLUSION

The chewing tobacco users exhibited greater amounts of nicotine and cotinine are at risk of cardiovascular due to nicotine has cardiovascular effects, and oral cancer disease complications in the future for chronic consumption of smokeless tobacco products  due to the presence of carcinogens of tobacco-specific N-nitrosamines.

LC-MS/MS Analysis of Sugars, Alditols, and Humectants in Smokeless Tobacco Products

Globally, smokeless tobacco (ST) includes a wide array of chemically diverse products generally used in the oral cavity. Although ST has been widely investigated, this study was undertaken to determine the levels of sugars (mono- and di-saccharides), alditols, and humectants present in major ST categories/subcategories by using high performance liquid chromatography coupled with a triple quadrupole mass spectrometer (HPLC-MS/MS). The products studied included chewing tobacco (loose leaf, plug, twist), US moist snuff, Swedish snus, creamy snuff, dry snuff, dissolvable tobacco products, and tobacco-coated toothpicks. The highest mean sugar level was detected in chewing tobacco (9.3-27.5%, w/w), followed by dissolvable tobacco (2.1%); all other products were lower than 1%. Creamy snuff had the highest mean alditol levels (22.6%), followed by dissolvable tobacco (15.4%); all others had levels lower than 1%. The detected mean humectant levels ranged from non-detectable to 5.9%. This study demonstrates the broad chemical diversity among ST. This research may aid researchers and public health advocates investigating the exposures and risks of ST. [Beitr. Tabakforsch. Int. 28 (2019) 203-213].

Maternal, prenatal and traditional practice factors associated with perinatal mortality in Yemen

BACKGROUND

Perinatal mortality remains a major international problem responsible for nearly six million stillbirths and neonatal deaths.

OBJECTIVES

To estimate the perinatal mortality rate in Sana'a, Yemen and to identify risk factors for perinatal deaths.

METHODS

A community-based prospective cohort study was carried out between 2015 and 2016. Nine-hundred and eighty pregnant women were identified and followed up to 7 days following birth. A multi-stage cluster sampling was used to select participants from community households', residing in the five districts of the Sana'a City, Yemen.

RESULTS

Total of 952 pregnant women were tracked up to 7 days after giving birth. The perinatal mortality rate, the stillbirth rate and the early neonatal mortality rate, were 89.3 per 1000, 46.2 per 1000 and 45.2 per 1000, respectively. In multivariable analysis older age (35+ years) of mothers at birth (Relative Risk=2.83), teenage mothers' age at first pregnancy (<18 years) (Relative Risk=1.57), primipara mothers (Relative Risk=1.90), multi-nuclear family (Relative Risk=1.74), mud house (Relative Risk=2.02), mothers who underwent female genital mutilation (Relative Risk=2.92) and mothers who chewed khat (Relative Risk=1.60) were factors associated with increased risk of perinatal death, whereas a positive mother's tetanus vaccination status (Relative Risk=0.49) were significant protective factors against perinatal deaths.

CONCLUSION

Rates of perinatal mortality were higher in Sana'a City compared to perinatal mortality at the national level estimated by World Health Organization. It is imperative there be sustainable interventions in order to improve the country's maternal and newborn health.

Individual and Integrated Effects of Potential Risk Factors for Oral Squamous Cell Carcinoma: A Hospital-Based Case-Control Study in Jazan, Saudi Arabia

Background: Oral cancer is the sixth most common cancer in the world, with a high prevalence reported in Jazan province of Saudi Arabia. The objectives of this study were to check individual and integrated effects of potential risk factors for oral squamous cell carcinoma. Materials and methods: A case control study was designed with a sample of 210 subjects, in which histopathologically confirmed incident cases (n=70) and controls (n=140) matched for age, gender and referral route, were recruited. Differences in exposure to potential risk factors between cases and controls were assessed using chi-square and McNemar analyses. A logistic regression model with interactions was applied to check individual and integrated effects. Results: Mean age of the sample was 55 years (+ 20 years). Shammah (O.R = 33.01; C.I = 3.22 – 39.88), shisha (O.R = 3.96; C.I = 0.24 – 63.38), and cigarette (O.R = 1.58; C.I = 0.13, 2.50) consumption was significantly associated (P<0.05) with oral squamous cell carcinoma development. In contrast, Khat chewing (O.R = 0.67; C.I = 0.19-2.36) was without significant effect. An increase in odds ratios was observed when combinations of shammah and shisha (O.R = 35.03; C.I = 11.50-65.66), shisha and cigarettes (O.R = 10.52; C.I = 1.03 – 33.90) or shamma and cigarettes (O.R = 10.10; C.I = 0.50 - 20.40) were used. Conclusion: Combined exposure to risk-factors has serious implications and policies on oral cancer prevention should be designed with attention to this aspect.

Simultaneous determination of nicotine, cotinine, and nicotine N-oxide in human plasma, semen, and sperm by LC-Orbitrap MS

Nicotine (Nic) distribution in human fluids and tissues has a deleterious effect on human health. In addition to its poisoning profile, Nic may contribute to the particular impact of smoking on human reproduction. Although present in seminal fluid, still nobody knows whether nicotine is available in sperm or not. Herein, we developed and validated a new bioanalytical method, for simultaneous determination of Nic, cotinine (Cot), and nicotine N'-oxide (Nox) in human plasma, semen, and sperm by LC-ESI-orbitrap-MS. Blood and semen samples were collected from 12 healthy smoking volunteers in this study. Sperm bodies were then separated quantitatively from 1 mL of semen samples by centrifugation. The developed method was fully validated for plasma following European and American guidelines for bioanalytical method validation, and partial validation was applied to semen analysis. Plasma, semen, and sperm samples were treated by trichloroacetic acid solution for protein direct precipitation in single extraction step. The established calibration range for Nic and Nox in plasma and semen was linear between 5 and 250 ng/mL, and for Cot between 10 and 500 ng/mL. Nic and Cot were detected in human sperm at concentrations as high as in plasma. In addition, Nox was present in semen and sperm but not in plasma. Graphical abstract Nicotine correlation between plasma and semen a; Nicotine correlation between semen and sperm c; Cotinine correlation between plasma and semen b; Cotinine correlation between semen and sperm d.

Non-cigarette tobacco and poly-tobacco use among persons living with HIV drawn from a nationally representative sample

INTRODUCTION

Smoking is more prevalent among persons living with HIV (PLWH) than the general population. Little is known about the prevalence of non-cigarette tobacco and poly-tobacco use (PTU; using multiple tobacco products) among this population, which, in the general population is associated with poor health and cessation outcomes. We aimed to characterize the prevalence of cigarette and non-cigarette tobacco use, PTU, and correlates of tobacco use status among a nationally-representative sample of PLWH.

METHODS

Data came from 472 HIV-positive adults from the 2005-2013 National Survey on Drug Use and Health (NSDUH).

RESULTS

The prevalence of PTU overall was 8.7% (95% CI=5.6-13.2), and 16.6% (95% CI=10.2-25.7) among past-year tobacco users. In multinomial logistic regression analyses, participants with a high school education or greater (aRRR=2.03, 95% CI=1.03-4.00) were more likely to be non-tobacco users than single product users. Past year drug users (aRRR=0.35, 95% CI=0.19-0.66) and past month binge drinkers (aRRR=0.24, 95% CI=0.12-0.50) were less likely to be non-tobacco users than single product users. Compared to 18-25 year olds, individuals age 26-34 (aRRR=0.13, 95% CI=0.03-0.65) and 35+ (aRRR=0.24, 95% CI=0.09-0.63), and with lifetime anxiety disorder(s) (aRRR=0.18, 95% CI=0.06-0.57) were less likely to be PTUs as compared to single product users. Individuals who reported liking to test themselves by doing risky things were more likely to be PTUs than single product users (aRRR=2.95, 95% CI=1.27-6.84).

CONCLUSIONS

PTU was slightly higher than in the general population, and should be taken into account when developing cessation interventions tailored to tobacco users living with HIV.

Short-term acute effects of gutkha chewing on heart rate variability among young adults: A cross-sectional study

BACKGROUND AND OBJECTIVES

An increase in the consumption of smokeless tobacco has been noticed among high school, college students, and adults. Despite the antiquity and popularity of chewing tobacco in India, its effects have not been investigated systematically in humans. The aim of this study was to investigate acute effects of gutkha chewing on heart rate variability (HRV) among healthy young adults.

MATERIALS AND METHODS

A total of 60 young adult males were included in the study. Each individual was asked to chew tobacco and subjected to HRV analysis. HRV analysis using short-term electrocardiogram recording was used to measure HRV parameters before gutkha chewing and at 5, 15, and 30 min after chewing tobacco. One-way analysis of variance and paired t-test was used to assess changes over time.

RESULTS

There was a significant increase in heart rate (HR) during tobacco chewing. Mean HR at baseline measured 73.0 ± 6.2 bpm. There was a rise in mean HR to 83.7 ± 9.1 bpm at 5 min during tobacco chewing and gradual reduction to baseline observed after 15 min followed by no significant change till 30 min. The normalized low-frequency power and LF/high-frequency (HF) power ratio were elevated after 5 min; however, normalized HF power was reduced after 5 min tobacco chewing.

CONCLUSION

Gutkha is closely associated with traditional cardiovascular risk factors as detected by a transient enhancing sympathetic activity during tobacco chewing in the form of increased HRV parameters or an imbalance between sympathetic and parasympathetic neural activity among healthy young adults.

Do Socioeconomic Risk Factors for Cigarette Smoking Extend to Smokeless Tobacco Use?

INTRODUCTION

Individuals with lower socioeconomic status (SES) are at increased risk for cigarette smoking. Less research has been conducted characterizing the relationship between SES and risk of using of other tobacco products. The present study examined SES as a risk factor for smokeless tobacco (ST) use in a US nationally representative sample, utilizing data from the 2012 National Survey on Drug Use and Health.

METHODS

Odds were generated for current cigarette smoking and ST use among adults (≥18 years) based on SES markers (educational attainment, income, blue-collar employment, and unemployment) after controlling for the influence of demographics and other substance dependence.

RESULTS

Odds of current cigarette smoking increased as a graded, inverse function of educational attainment as well as lower income and being unemployed. Odds of current ST use also increased as a function of lower educational attainment, although not in the linear manner seen with cigarette smoking. Odds of ST use but not cigarette smoking also increased with blue-collar employment. In contrast to patterns seen with cigarette smoking, ST use did not change in relation to income or unemployment.

CONCLUSIONS

Markers of SES are significantly associated with odds of cigarette smoking and ST use, but which indicators are predictive and the shape of their relationship to use differs across the two tobacco products.

Electronic Cigarettes—A Narrative Review for Clinicians

Electronic cigarettes (e-cigarettes) were introduced into the US market in 2007 and have quickly become a popular source of nicotine for many patients. They are designed to simulate smoking by heating a nicotine-containing solution producing an aerosol that the user inhales. The short- and long-term effects of e-cigarette use are still unclear, but their use is increasing. Some acute effects of e-cigarettes on heart rate, blood pressure, and airway resistance are reported. Although there are some reports of improved cessation in a subset of users, there are also studies reporting decreased cessation in dual users of regular and e-cigarettes. Additionally, there is no current regulation of these devices, and this allows virtually anyone with a form of online payment to obtain them.

Striatal dopamine release regulation by the cholinergic properties of the smokeless tobacco, gutkha

Tobacco products influence striatal dopamine (DA) release primarily through the actions of nicotine, an agonist of nicotinic acetylcholine receptors (nAChR). Gutkha is a smokeless tobacco product that contains not only nicotine, but also includes the habit-forming areca nut and other plant-based constituents that contribute muscarinic acetylcholine receptor (mAChR) agonists and other cholinergic agents. Thus, the net influence of the cholinergic agents in gutkha on striatal DA release is difficult to predict. This study investigated the influence of gutkha extract on evoked DA release in mouse striatal slices using fast-scan cyclic voltammetry. The potency of a given concentration of nicotine in the gutkha extract was found to be significantly lower than that of a comparable concentration of nicotine alone. Atropine, a mAChR antagonist, increased the potency of gutkha-associated nicotine; however, other experiments suggested that this was mediated in part by direct effects of atropine at nAChRs. Overall, these results suggest that the unique constituents of gutkha work together to oppose the influence of gutkha-associated nicotine on evoked striatal DA release.

Smokeless tobacco (shammah) in Saudi Arabia: a review of its pattern of use, prevalence, and potential role in oral cancer

BACKGROUND

Shammah is a traditional form of chewing tobacco [smokeless tobacco, (ST)] that is commonly used in the Middle East especially in Saudi Arabia (KSA), Yemen and Sudan. The Substance Abuse Research Centre (SARC) at Jazan University noted that no adequate research and information on the prevalence of shammah use in the province of Jazan, and KSA as well, has been provided in the scientific literature.

MATERIALS AND METHODS

An intensive systematic review of online databases was performed, including AMED (The Allied and Complementary Medicine Database), Biological Abstracts, Cochrane Collection Plus, Dentistry and Oral Sciences Source, E-Journals Database, EBSCO Discovery Service, MEDLINE, PEMSoft, PEP Archive, PsycARTICLES, scopus, Sciencedirect and Google Scholar.

RESULTS

Shammah is a mixture of powdered tobacco, lime, ash, black pepper, oils and flavorings. ST in KSA is placed in the buccal or lower labial vestibule of the mouth. The user (or dipper) spits out insoluble debris. The importation of ST products is prohibited in KSA. Accessible information on legislative action to control the use of ST in KSA appeared in 1990. The actual percentage use may be higher, than reported since shammah is illegal in KSA and there may be some reluctance to admit to its use.

CONCLUSIONS

This review paper is an initial step in a funded research project by SARC to understand the pattern of use of shammah and provide adequate epidemiological data. One goal of this review is to generate further data for public health education.

Physical activity, fatness, educational level and snuff consumption as determinants of semen quality: findings of the ActiART study

In this study, the association between physical activity and other potential determinants, objectively measured by accelerometry, was examined. Sixty-two men attending an infertility clinic participated in the study. Obese men (body mass index ≥ 30) and those with a waist circumference 102 cm or more had lower semen volume than the other men (P < 0.05). Higher values in sperm parameters were observed in participants who completed university studies and those who did not consume snuff, compared with the other participants (P < 0.05). Finally, men who spent an average number of 10 min-bouts of moderate-to-vigorous physical activity had significantly better semen quality than those who engaged in low or high numbers of bouts of activity (P < 0.05). No associations were found for sedentary or moderate-to-vigorous physical activity time when it was not sustained over 10 min, i.e. not in bouts. Men who have average levels of physical activity over sustained periods of 10 min are likely to have better semen quality than men who engage in low or high levels of such activity. Similarly, high levels of total and central adiposity, low educational level and snuff consumption are negatively related to semen quality.

Examining vulnerability to smokeless tobacco use among adolescents and adults meeting diagnostic criteria for major depressive disorder

Smoking prevalence is unevenly distributed in the U.S. population, with those with mental illness, other substance use disorders, and lower socioeconomic status being especially vulnerable. Less research has been conducted on the association between these same vulnerabilities and smokeless tobacco (ST) use. The present study examined cigarette and ST use among adolescents and adults who met diagnostic criteria for major depressive disorder in the National Survey on Drug Use and Health (NSDUH). Utilizing the most recent (2011) NSDUH, we compared odds for current cigarette smoking and ST use among adolescents and adults meeting criteria for past-year major depressive disorder to the general population, after adjusting for potential confounding influences of sociodemographic and other substance use characteristics. Analyses were conducted to examine sex as a moderator of the relation between major depressive disorder and tobacco use. Odds for current cigarette smoking among those classified with major depressive disorder were increased among adolescents (OR = 1.33, 95% CI [1.05, 1.69], p = .021) and adults (OR = 1.70, 95% CI [1.47, 1.97], p < .0005), and odds for current ST use did not differ among adolescents (OR = 0.90, 95% CI [0.54, 1.49], p = .678) and were lower among adults (OR = 0.68, 95% CI [0.51, 0.91], p = .010). Sex was not a significant moderator in adolescents or adults. Major depressive disorder is associated with increased risk for smoking but not ST use among adolescents and adults further demonstrating heterogeneity in predictors of vulnerability to use of different tobacco products.

Combusted but not smokeless tobacco products cause DNA damage in oral cavity cells

The aim of this work was to investigate genomic DNA damage in human oral cavity cells after exposure to different tobacco product preparations (TPPs). The oral carcinoma cell line 101A, gingival epithelial cells HGEC, and gingival fibroblasts HGF were exposed to TPM (total particulate matter from 3R4F cigarettes), ST/CAS (2S3 smokeless tobacco extract in complete artificial saliva), and NIC (nicotine). Treatments were for 24 h using TPM at its EC-50 doses, ST/CAS and NIC at doses with equi-nicotine units, and high doses for ST/CAS and NIC. Comet assays showed that TPM, but not ST/CAS or NIC, caused substantial DNA breaks in cells; only the high ST/CAS dose caused weak DNA damage. These results were confirmed by immunofluorescence for γ-H2AX protein. These data revealed that the combusted TPP caused substantial DNA damage in all cell types, whereas the two non-combusted TPPs exerted no or only minimal DNA damage. They support epidemiologic evidence on the relative risk associated with consumption of non-combusted versus combusted tobacco products, and help to understand potential genotoxic effects of such products on oral cavity cells.

Toxicity of gutkha, a smokeless tobacco product gone global: is there more to the toxicity than nicotine?

The popularity of smokeless tobacco (ST) is growing rapidly and its prevalence of use is rising globally. Consumption of Gutkha, an addictive form of ST, is particularly common amongst South Asian communities throughout the World. This includes within the US, following large-scale immigration into the country. However, there exists a lack of knowledge concerning these alternative tobacco products. To this end, a study was carried out to determine the toxicity of gutkha, and what role, if any, nicotine contributes to the effects. Adult male mice were treated daily for 3-week (5 day/week, once/day), via the oral mucosa, with equal volumes (50 μL) of either sterile water (control), a solution of nicotine dissolved in water (0.24 mg of nicotine), or a solution of lyophilized guthka dissolved in water (21 mg lyophilized gutkha). Serum cotinine, measured weekly, was 36 and 48 ng/mL in gutkha- and nicotine-treated mice, respectively. Results demonstrated that exposure to nicotine and gutkha reduced heart weight, while exposure to gutkha, but not nicotine, decreased liver weight, body weight, and serum testosterone levels (compared to controls). These findings suggest that short-term guhtka use adversely impacts growth and circulating testosterone levels, and that gutkha toxicity may be driven by components other than nicotine. As use of guthka increases worldwide, future studies are needed to further delineate toxicological implications such that appropriate policy decisions can be made.

The changing face of tobacco use among United States youth

Tobacco use, primarily in the form of cigarettes, is the leading cause of preventable morbidity and mortality in the United States (U.S.). The adverse effects of tobacco use began to be recognized in the 1940's and new hazards of active smoking and secondhand smoke (SHS) exposure from cigarettes continue to be identified to this day. This has led to a sustained and wide-ranging array of highly effective regulatory, public health, and clinical efforts that have been informed by extensive scientific data, resulting in marked decreases in the use of cigarettes. Unfortunately, the dramatic recent decline in cigarette use in the U.S., has been accompanied by an upsurge in adolescent and young adult use of new, non-cigarette tobacco and nicotine-delivery products, commonly referred to as alternative tobacco products (ATPs). Commonly used ATPs include hookah, cigars, smokeless tobacco, and electronic cigarettes. While there have been a number of review articles that focus on adult ATP use, the purpose of this review is to provide an overview of what is, and is not known about emerging ATP use among U.S. adolescents on a national scale; as well as to identify research gaps in knowledge, and discuss future health and policy needs for this growing public health concern. This paper is not meant to systemically review all published survey data, but to present clear depiction of selected ATP usage in youth populations using national survey data.

Vulnerability to smokeless tobacco use among those dependent on alcohol or illicit drugs

INTRODUCTION

Individuals dependent on alcohol or illicit drugs are vulnerable to cigarette smoking and related adverse health outcomes. Less research has been conducted regarding whether these same groups are vulnerable to smokeless tobacco (ST) use. The goal of this study is to examine vulnerability to ST use among individuals with other drug dependence.

METHODS

Utilizing the most recent (2011) National Survey on Drug Use and Health (NDSUH), we determined odds ratios (ORs) for current cigarette smoking and ST use among those with current alcohol, cocaine, heroin, and marijuana dependence, adjusting for relevant sociodemographic characteristics. Vulnerability to cigarette smoking was assessed to confirm that alcohol and illicit drug dependence were associated with increased smoking in these data sets, as shown in prior studies. Identical analyses were completed in the 2009 and 2010 NSDUH to assess generality.

RESULTS

Odds for current cigarette smoking were increased for each category of dependence (p < .0005): alcohol (OR with 99% CI = 3.30 [2.58, 4.21]), cocaine (OR = 4.50 [1.53, 13.20]), heroin (OR = 7.84 [1.92, 32.03]), and marijuana (OR = 3.55 [2.59, 4.88]). Odds for current ST use were also increased among those with alcohol dependence (OR = 1.56 [1.06, 2.30], p = .003) but not illicit drug dependence. Generality of the findings was confirmed in the 2009 and 2010 NSDUH.

CONCLUSIONS

Consistent with earlier reports, alcohol and illicit drug dependence are associated with robust increases in risk for cigarette smoking. In the case of alcohol dependence, but not illicit drug dependence, this vulnerability also extends to ST use.

Poly-tobacco use among HIV-positive smokers: implications for smoking cessation efforts

INTRODUCTION

Poly-tobacco use is defined as cigarette and other tobacco consumption with either product used daily or nondaily. While concurrent use of different types of tobacco has been documented within the general population, less is known about poly-tobacco use among HIV-positive smokers and its impact on smoking cessation efforts.

OBJECTIVE

To characterize the profile of poly-tobacco users (PTU) in a sample of HIV-positive smokers participating in a cessation program.

METHODS

The study sample consisted of 474 HIV-positive smokers enrolled in a 2-group randomized controlled trial of cigarette smoking cessation comparing a cell phone-based intervention to usual care. Prevalence was determined, and risk factors for poly-tobacco use were evaluated using logistic regression.

RESULTS

In this cohort of HIV-positive cigarette smokers, 21.6% of participants were PTU, with cigars (73.4%) the most common tobacco product consumed. Among PTU, 73.5% used other form(s) of tobacco some days, and 26.5% use them every day. Perceived discrimination and unemployment were significantly associated with poly-tobacco use after adjusting for other demographic, behavioral, and psychosocial factors. Analysis showed that participants in the cell phone group (vs. usual care) were more likely to report 24-hr abstinence, both among monocigarette users (16.6% vs. 6.3%, p < .001) and PTU (18.5% vs. 0%, p < .001).

CONCLUSION

Poly-tobacco use prevalence among adult HIV-positive smokers was considerably higher than in the general population. Special attention must be placed on concurrent use of cigarettes and cigars among HIV-positive smokers. Because PTU are a unique population less likely to succeed in brief smoking cessation interventions, effective cessation programs are needed.