Hemodynamic effects of oral smokeless tobacco in dogs and young adults

The Effect of Dipping Tobacco on Pulse Wave Analysis among Adult Males

BACKGROUND

The current study investigated the effect of dipping tobacco (DT) use on arterial wall stiffness which is a known marker of increased risk of cardiovascular events.

METHODS

A case-control study which included 101 adult males was carried out in Al-Shaab Teaching Hospital. Blood pressure and pulse wave analysis parameters were recorded in 51 DT users (study group) before and after 30 minutes of placing tobacco and in 50 nontobacco users (control group). Anthropometric measurements were collected using data collection sheet. Data were entered into a computer and analyzed by using the software Statistical Package for the Social Sciences (SPSS) version 20 (SPSS Inc., Chicago, IL, USA).

RESULTS

At baseline measurements, heart rate (HR) was significantly lower in the study group compared to the control group (66.15 ± 9.21 vs. 72.87 ± 10.13 beats/min; P value ≤ 0.001). Subendocardial viability ratio (SEVR) was significantly higher in the study group compared to the control group (203.44 ± 30.34 vs. 179.11 ± 30.51%; P value ≤ 0.001). Acute effects of DT compared to pretobacco dipping showed significant increase in HR (72.50 ± 10.89 vs. 66.15 ± 9.21 beats/min; P value ≤ 0.001) and significant decrease in augmentation pressure (AP) (4.30 (2.30-8.00) vs. 3.30 (0.60-6.3) mmHg; P value ≤ 0.001), ejection duration (ED) (271.65 ± 19.42 vs. 279.53 ± 20.47 ms; P value ≤ 0.001), and SEVR (187.11 ± 29.81 vs. 203.44 ± 30.34; P value ≤ 0.001). Linear regression analysis for AP predictor showed that only HR and AIx@75 affect and predict the values of AP (Beta ± SE; -0.242 ± 0.019, P value ≤ 0.001; 0.685 ± 0.014, P value ≤ 0.001).

CONCLUSIONS

Long-term use of DT was not associated with permanent changes in heart rate and blood pressure. Acute tobacco dipping caused an acute increase in heart rate and oxygen demands of myocardium.

N, K. S, C. VK, K. ND, C. SK, Maddu N. Smokeless tobacco induced biophysical and biochemical alterations in the plasma, erythrocytes, and platelets of panmasala users: Subsequent biological effects

AIM & BACKGROUND

Smokeless tobacco (SLT) products are extensively consumed throughout the world including India. These products act as the primary addictive agents, due to the presence of nicotine among other tobacco products to humans and animals and its quitting is difficult. Higher the exposure of SLT products more is the toxic effects and alterations in erythrocytes and platelets.

OBJECTIVES

The products of smokeless tobacco could cause increase in the concentrations of oxidants (free radicals), decrease the activities antioxidant enzymes, activate the process of programmed cell death through enhanced expression of inducible nitric oxide synthase. Smokeless tobacco products represent a major modifiable risk factor for the development of redox imbalance through the enhanced production of reactive oxygen species and diminished activities of antioxidant enzymes in plasma, bio-membranes of erythrocytes, and platelets and induction of apoptosis in the blood.

MATERIALS AND METHODS

The protein expression of inducible nitric oxide synthase (iNOS) was studied by western blot and gene expression of apoptotic proteins, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) was evaluated by RT-PCR technique. Membrane fluidity of erythrocytes and platelets was studied by the fluorescence method.

RESULTS

The results of the present study revealed that significantly elevated levels of iNOS enzyme in plasma, erythrocyte, and platelet membranes of panmasala users. We found that gene expression levels of Bcl2, Bax, IL-6, caspase proteins (Caspase 8, Caspase 10, and Caspase 12) are greater and decreased levels of TNF-α with no significant change in blood of smokeless tobacco users in comparison with normal controls. In addition, there were substantial significantly higher in concentrations of nicotine, cotinine, and epinephrine in the plasma of panmasala users than non-tobacco users. Panmasala can be caused a significant increase in nitroxidative stress marker (LPO, NO, and ONOO-) values and significant decrease in the levels of antioxidant enzymes in erythrocytes and platelets.

CONCLUSION

On the basis of the present study results, it may be concluded that the chronic use of panmasala than any smokeless tobacco products may be a contributory risk factor or may give conclusive idea and has been associated with the expansion of the development of structural and functional alterations in the erythrocyte and platelet membranes induced oxidative damage and apoptosis, possibly further enhanced by nicotine and tobacco-specific N-nitrosamines. SLT exposure had implicated a threat and enormous implications on public health and is required to prove that may not be viewed as a safe alternative to any tobacco products.

Smokeless tobacco: Risk factor for cardiovascular and breathing in young Indian adolescent

BACKGROUND

Teenagers are the foremost susceptible population to smokeless tobacco usage and limited studies have surveyed the influence of smokeless tobacco on cardiac and respiratory response.

OBJECTIVE

This study aims to measure consequence (cardiovascular and breathing) of smokeless tobacco usage (gutkha and chewing tobacco) among young Indian men.

METHOD

On random basis, the applicants were divided into Group I (n=50) - healthy control group, Group II (n=50) - smokeless tobacco users. Anthropometric measurements and recording of blood pressure (BP), pulse wave analysis (PWV), heart rate variability (HRV) and pulmonary function test (PFT) was performed.

RESULT

We observed that altogether anthropometric variables were comparable among all individuals. In blood pressure variable, except DBP, other variables for example SBP, PP and MAP were significantly increased in Group II individuals, once compare to Group I. Pulse wave analysis, (such as, AP, AIx, and SEVR), was comparable in individuals of both groups. As compare to Group I, HR was significantly increased in Group II. In HRV investigation, NN, VLF, LF, LF(nu), LF/HF were increased significantly and TSP, HF, HF(nu) were decreased significantly in Group II with compare to Group I. In PFT analysis, FVC was comparable among individuals of both the group and conversely, significant decrease in FEV₁, FEV₁/FVC, FEF_25-75 and PEFR in Group II when compare with Group I.

CONCLUSION

This study illustrate that smokeless tobacco practice has increasing adverse effects on cardiovascular as well as breathing system and become an important public health problem.

Exercise performance increase in smokeless tobacco-user athletes after overnight nicotine abstinence

The use of nicotine administered through smokeless tobacco (snus) has increased among athletes. The purpose of this study was to investigate the ergogenic effects of snus on aerobic performance during exercise until exhaustion in athletes after abstinence or satiety nicotine conditions. The study utilized a randomized, controlled, within-subject design experiment. Sixteen male snus-user athletes completed an exercise until exhaustion at a constant load of their 80% of V ˙ O 2 max (calculated by a maximal incremental test) in two separate sessions, corresponding to nicotine conditions: 12-hour overnight abstinence and satiety. A portion of 1 g of snus (~8 mg/g of nicotine) was administered 25 minutes before each experimental test. In each session, time to exhaustion (TTE), global rating of perceived exertion, cardiovascular and metabolic responses, and muscle and cerebral oxygenation were measured. Nicotine and cotinine analysis confirmed session conditions (abstinence or satiety). Snus induced a significant increase (+13.1%) of TTE following abstinence (24.1 ± 10.7 minutes) compared to satiety condition (20.9 ± 8.0 minutes; P = 0.0131). The baseline values revealed that abstinence of snus induced significant increase in the oxygenation of the muscular tissues (+4%), in metabolic values and in cardiovascular parameters, when compared to satiety condition. Our results indicate an increase of exercise performance (+13.1% TTE) due to snus administration in an abstinence condition. Considering that twelve hours of abstinence from snus-contained nicotine affected metabolic, cardiovascular and muscular tissue oxygenation, we suggest that snus administration at test time might relieve these withdrawal changes and yield an increase in time to exhaustion.

Regular moist snuff dipping does not affect endurance exercise performance

Physiological and medical effects of snuff have previously been obtained either in cross-sectional studies or after snuff administration to non-tobacco users. The effects of snuff cessation after several years of daily use are unknown. 24 participants with >2 years of daily snuff-use were tested before and after >6 weeks snuff cessation (SCG). A control group (CO) of 11 snuff users kept their normal habits. Resting heart rate (HR) and blood pressure (BP) were significantly lower in SCG after snuff cessation, and body mass was increased by 1.4 ± 1.7 kg. Total cholesterol increased from 4.12 ± 0.54 (95% CI 3.89–4.35) to 4.46 ± 0.70 (95% CI 4.16–4.75) mM L^–1 in SCG, due to increased LDL, and this change was significantly different from CO. Resting values of HDL, C-reactive protein, and free fatty acids (FFA) remained unchanged in both groups. In SCG group, both HR and BP were reduced during a four-stage incremental cycling test (from 50 to 80% of VO₂max) and a prolonged cycling test (60 min at 50% of VO₂max). Oxygen uptake (VO₂), respiratory exchange ratio, blood lactate (bLa) and blood glucose (bGlu) concentration, and rate of perceived exertion (RPE) were unchanged. In CO group, all measurements were unchanged. During the prolonged cycling test, FFA was reduced, but with no significant difference between groups. During the maximal treadmill running test peak values of VO₂, pulmonary ventilation (V_E), time to exhaustion and bLa were unchanged in both groups.

In conclusion, endurance exercise performance (VO₂max and maximal endurance time) does not seem to be affected by prolonged snuff use, while effects on cardiovascular risk factors are contradictory. HR and BP during rest and submaximal exercise are reduced after cessation of regular use of snuff. Evidently, the long-time adrenergic stress on circulation is reversible.

Is smokeless tobacco a risk factor for coronary heart disease? A systematic review of epidemiological studies

BACKGROUND

There is on-going debate about the wisdom of substituting smokeless tobacco products for cigarette smoking as a 'harm reduction' strategy. It is generally believed that health risks associated with smokeless tobacco use (ST) are lower than those with cigarette smoking. However, the population attributable risk of smoking is higher for cardiovascular diseases than for any cancers, and few studies or reviews have considered the cardiovascular outcomes of ST use. A systematic review was therefore carried out to highlight the gaps in the evidence base.

METHODS

Electronic databases were searched, supplemented by screening reference lists, smoking-related websites, and contacting experts. Analytical observational studies of ST use (cohorts, case-control, cross-sectional studies) were included if they reported on cardiovascular disease (CVD) outcomes, or risk factors. Data extraction covered control of confounding, selection of cases and controls, sample size, clear definitions and measurements of the health outcome and ST use. One or two independent reviewers carried out selection, extraction and quality assessments.

RESULTS

A narrative review was carried out. Very few studies were identified; only three from Sweden consider CVD outcomes and these are discrepant. There may be a modest association between use of Swedish snuff (snus) and cardiovascular disease (e.g., relative risk=1.4, 95% confidence interval 1.2-1.6) in one prospective cohort study. Several other studies have considered associations between ST use and intermediate outcomes (CVD risk factors).

CONCLUSIONS

There may be an association between ST use and cardiovascular disease. However, further rigorous studies with adequate sample sizes are required.

Smokeless tobacco, sport and the heart

Smokeless tobacco (snuff) is a finely ground or shredded tobacco that is sniffed through the nose or placed between the cheek and gum. Chewing tobacco is used by putting a wad of tobacco inside the cheek. Smokeless tobacco is widely used by young athletes to enhance performance because nicotine improves some aspects of physiology. However, smokeless tobacco has harmful health effects, including cardiovascular disorders, linked to nicotine physiological effects, mainly through catecholamine release. Nicotine decreases heart rate variability and the ventricular fibrillation threshold, and promotes the occurrence of various arrhythmias; it also impairs endothelial-dependent vasodilation and could therefore promote premature atherogenesis. At rest, heart rate, blood pressure, inotropism, cardiac output and myocardial oxygen consumption are increased by nicotine, leading to an imbalance between myocardial oxygen demand and supply. The same occurs at submaximal levels of exercise. These increases are accompanied by a rise in systemic resistances. At maximal exercise, heart rate, cardiac output and maximal oxygen uptake (V˙O2max) are unaffected by nicotine. Because endothelial dysfunction is promoted by nicotine, paradoxical coronary vasoconstriction may occur during exercise and recovery. Nicotine induces a decrease in muscular strength and impairs anaerobic performance. However, nicotine is used in sports as it diminishes anxiety, enhances concentration and agility, improves aerobic performance and favours weight control. Importantly, smokeless tobacco, similar to cigarette smoking, leads to nicotine dependence through dopaminergic pathways. Smokeless tobacco has harmful cardiovascular effects and is addictive: it fulfils all the criteria for inclusion in the World Anti-Doping Agency prohibited list as a doping product. Smokeless tobacco use in sporting activities must be discouraged.

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

The popularity of smokeless tobacco (ST), or noncombusted tobacco, usually placed within the mouth to be chewed, sucked, or swallowed, is growing rapidly and its prevalence of use is rising globally, due (in part) to greater convenience, as allowable cigarette smoking areas are rapidly decreasing, and increased social acceptability. Though data are limited, ST usage has been directly linked to a number of adverse health outcomes. The potential role that immune dysfunction, including dysregulation of immune cells and their components, may play in the progression of these adverse health outcomes is only just beginning to emerge. Evidence suggesting reproductive outcomes, such as perinatal mortality, preterm birth, and reduced sperm viability, also exists in conjunction with ST use. Cardiovascular health may also be impacted by ST use, resulting in increased blood pressure and endothelial dysfunction, both of which may potentially lead to cardiovascular diseases. This review describes the toxicological implications associated with ST use, with emphasis on immune, reproductive, and cardiovascular outcomes. Epidemiological studies are discussed with respect to experimental studies to help develop the relationship between ST and disease pathology. This review also summarizes the gaps in ST knowledge and potential future directions that are needed to more fully delineate the complex systems driving the adverse health outcomes associated with its use.

The association between active smoking, smokeless tobacco, second-hand smoke exposure and insufficient sleep

BACKGROUND

Studies have shown that cigarette smoking is associated with sleep disorders in the general population. But studies examining the association between smokeless tobacco use, second-hand smoke exposure and insufficient rest/sleep are limited.

METHODS

We examined the association between smoking, smokeless tobacco use (n=83,072), second-hand smoke exposure (n=28,557) and insufficient rest/sleep among adults aged ≥20 years in the state-based 2008 Behavioral Risk Factor Surveillance System. Exposure to second-hand smoke was defined as >1 day of exposure to cigarette smoking either at home or in the workplace in the preceding 7 days. Insufficient rest/sleep was defined as not getting enough rest/sleep everyday in the preceding 30 days.

RESULTS

Compared to never smokeless tobacco users, the odds ratio (OR; 95% confidence interval [CI]) of insufficient rest/sleep was 1.16 (1.00-1.36) and 1.74 (1.37-2.22) among former and current users. Compared to non-smokers/non-smokeless tobacco users, the OR (95% CI) of insufficient rest/sleep for those who were both current smokers and current smokeless tobacco users was 2.21 (1.66-2.94). Regarding second-hand smoke exposure among non-smokers, those with second-hand smoke exposure had higher odds for insufficient rest/sleep than those without. In contrast, the odds of insufficient rest/sleep were similar among current smokers with or without second-hand smoke exposure.

CONCLUSIONS

In a multiethnic sample of US adults, compared to non-smokers/non-smokeless tobacco users, those who were both current smokers and current smokeless tobacco users had twice the odds of insufficient sleep. Second-hand smoke exposure was associated with insufficient rest/sleep among non-smokers.

The acute effects of smokeless tobacco on central aortic blood pressure and wave reflection characteristics

The main objectives of this study were to examine the acute effect of a single dose of smokeless tobacco (ST) on central aortic blood pressure and wave reflection characteristics. Fifteen apparently healthy male subjects (aged 30.6 ± 6.2 y) were given a 2.5 g oral dose of ST after baseline measurements were recorded. Pulse wave analysis using radial artery applanation tonometry was performed in triplicate at baseline (0 min) and at 10-min intervals during (10, 20 and 30 min) and after (40, 50 and 60 min) ST use. An acute dose of ST was associated with a significant increase in heart rate (HR), central aortic systolic and diastolic blood pressure, peripheral brachial systolic and diastolic blood pressure, and aortic augmentation index normalized to a fixed heart rate of 75 bpm (AIx@75). Furthermore, ejection duration and round trip travel time of the reflected pressure wave (Δt(p)) were significantly decreased as a result of one time ST use. As a result of changes in aortic pressure wave reflection characteristics, there was a significant increase in wasted left ventricular pressure energy (LVE(w)) and the tension-time index (TTI) as a result of ST use. In conclusion, one time use of ST elicits significant transient increases in HR, central aortic pressures, AIx@75, the TTI and LVE(w). Chronic users subjected to decades of elevated central pressures and left ventricular work may have an increased cardiovascular risk as central aortic pressures are even more strongly related to cardiovascular outcomes than peripheral blood pressures.

Risk of hypertension amongst Swedish male snuff users: a prospective study

BACKGROUND

The scientific evidence on whether long-term use of snuff is associated with high blood pressure is limited, inconsistent and based only on cross-sectional data.

OBJECTIVE

We aimed at studying the risk of hypertension in relation to long-term use of snuff based on longitudinal data.

DESIGN

Repeated health check-ups were offered to all employees in the Swedish construction industry between 1978 and 1993. Blood pressure was measured at the health check-up and information on tobacco use and other risk factors was collected through questionnaires.

SETTING

In total, 120 930 never smoking men with information on blood pressure and snuff use at baseline were included. The association of high blood pressure and snuff use at baseline was estimated by logistic regression. Further, 42 055 men were identified as normotensive at baseline and had at least one subsequent health check-up. Through repeated blood pressure measurements and linkage to the Swedish National Inpatient Register, information on hypertension was obtained. Relative risk estimates were derived from Cox proportional hazards regression model.

RESULTS

Almost 30% of all men had used snuff. The adjusted odds ratio of high blood pressure amongst snuff users at baseline was 1.23 (95% CI 1.15-1.33) compared to never snuff users. The relative risk of high blood pressure during follow-up was 1.39 (95% CI 1.08-1.79) amongst snuff users and 1.36 (95% CI 1.07-1.72) for hypertension as recorded in the Inpatient Register.

CONCLUSION

Use of Swedish moist snuff appears to be associated with a moderately increased risk of hypertension.

Circulatory disease and smokeless tobacco in Western populations: a review of the evidence

BACKGROUND

Use of oral snuff or 'snus' has risen in Sweden. Sales of snuff in the US have also risen, overtaking sales of chewing tobacco. There is some evidence that nicotine contributes to circulatory disease (CID) from smoking. We therefore reviewed the evidence relating smokeless tobacco (ST) to CID and related risk factors.

METHODS

Publications that described relevant cohort, case-control and cross-sectional studies were identified from in-house files, a Medline search in December 2005 and reference lists. Relative risks (RRs) and odds ratios (ORs) for ischaemic heart disease, stroke and all CID for ST use, stratified by smoking habit, were estimated and combined by meta-analysis to provide an overall RR estimate. For diabetes, increased blood pressure, and other risk factors, evidence was qualitatively reviewed, with results from clinical studies also considered.

RESULTS

ST use in non-smokers was associated with an increased risk of heart disease (RR 1.12, 95% CI 0.99-1.27, n = 8), stroke (1.42, 1.29-1.57, n = 5) and CID (1.25, 1.14-1.37, n = 3). The increases mainly derived from two large US studies. The Swedish studies provided little evidence of an increase for heart disease (1.06, 0.83-1.37, n = 5) or stroke (1.17, 0.80-1.70, n = 2), although the estimates by country are not notably heterogeneous, even for stroke (P = 0.29). No dose-response was evident. No increase was seen in former users of ST, or in ST users who also smoked. No clear relationship to diabetes was seen. In the US, an acute blood pressure rise following ST use was consistently reported, and isolated reports linked specific risk factors to ST. In Sweden, though one study reported that snuff acutely increased blood pressure, and two linked snuff to Raynaud-type symptoms, the overall evidence for an effect was inconclusive. Swedish studies generally showed no chronic effect of snuff on blood pressure or various risk factors.

CONCLUSIONS

Any CID risk from ST appears to be substantially less than from smoking, and no clear risk from Swedish snuff is seen. However, the overall evidence is limited.

Effect of nicotine on the renal microcirculation in anesthetized rats: a potential for medullary hypoxic injury?

BACKGROUND

Cigarette smoking has been associated with accelerated renal dysfunction among patients with chronic renal disease. Conceivably, repeated parenchymal hypoxic injury, induced by nicotine-related vasomotor changes, might contribute to the progression of renal failure in smokers.

METHODS

Renal blood flow and selective cortical and outer medullary blood flows were determined in anesthetized rats. Changes in total renal, cortical and medullary vascular resistance were calculated. Nicotine was repeatedly infused at rising doses (50-200 microg/kg) to intact (CTR) animals and to rats chronically administered with nicotine in their drinking water (NIC). In a complementary study, nicotine-treated and control rats were subjected to medullary hypoxic stress, induced by radiocontrast and indomethacin.

RESULTS

Chronic nicotine exposure led to lower baseline renal blood flow and creatinine clearance. Nicotine infusion induced a transient dose-dependent rise in blood pressure, renal blood flow and cortical flow, with a corresponding decline in renal vascular resistance and cortical resistance in both experimental groups. However, while medullary flow increased in CTR by up to 16 +/- 6%, it remained unchanged or even somewhat declined in the NIC group. Calculated medullary resistance reciprocally declined in CTR while it rose in the NIC group (p < 0.001). In animals subjected to radiocontrast and indomethacin, nicotine intensified renal dysfunction, associated with focal medullary hypoxic damage.

CONCLUSIONS

Chronic exposure to nicotine selectively compromises the outer medullary microcirculation, blunting a local vasodilatory response to acute nicotine administration. Repeated acute-on-chronic exposure to nicotine may predispose to hypoxic medullary injury.

Hemodynamic and autonomic effects of smokeless tobacco in healthy young men

OBJECTIVES

The aim of this study was to investigate the acute hemodynamic and autonomic effects of smokeless tobacco.

BACKGROUND

Smokeless tobacco use is increasing. Its cardiovascular effects are not well understood.

METHODS

Sixteen healthy, male, habitual snuff tobacco users (aged 22 +/- 1 year) were studied, using a randomized, double-blind, placebo-controlled, crossover design with two separate experimental sessions: placebo and tobacco. Muscle sympathetic nerve activity (MSNA), electrocardiogram, blood pressure, calf blood flow, nicotine, and catecholamines were measured.

RESULTS

Snuff tobacco increased plasma nicotine from 2.8 +/- 0.5 ng/ml to 10.4 +/- 1.1 ng/ml. Mean blood pressure increased by 10 +/- 1 mm Hg, and heart rate increased by 16 +/- 2 beats/min. Peripheral vascular resistance, MSNA, and norepinephrine concentration did not change with tobacco, but epinephrine increased by approximately 50%.

CONCLUSIONS

Oral snuff tobacco increases heart rate, blood pressure, and epinephrine. Despite the increase in blood pressure, there is no decrease in either MSNA or peripheral vascular resistance. Smokeless tobacco is a powerful autonomic and hemodynamic stimulus. Catecholamine release from the adrenal medulla likely contributes to this response.

Non-biochemical risk factors for cardiovascular disease in general clinic-based rural population of Bangladesh

BACKGROUND

Strategies for preventing premature cardiovascular disease include measures to control its risk factors. To plan such activities, prevalence of these factors must be known. Data regarding risk factor prevalence is limited in Bangladesh and measurement of biochemical factors is not always feasible. The aim of our study is to describe the non-biochemical risk factors in a clinic-based rural population of Bangladesh that would reflect at least a part of the problem in the rural area.

METHODS

A cross sectional study was done in a clinic based patient population aged 20 years and older (471 males and 800 females) in a rural community of Bangladesh. A questionnaire on lifestyle including dietary and smoking habit was administered and physical examinations including height, weight, waist circumference, and blood pressure were measured in standardized way.

RESULTS

Mean body mass index was 18.5 kg/m2 (standard deviation [SD]: 2.9 kg/m2) in males and 18.7 kg/m2 (SD: 3.3 kg/m2) in females. Mean systolic blood pressure was 120.0 mmHg (SD: 18.5 mmHg) and mean diastolic blood pressure 77.2 mmHg (SD: 9.9 mmHg) in all subjects. The prevalence of hypertension (140+/90+ mmHg and/or on treatment) was 17.8%. Prevalence of tobacco consumption (smoking and chewing) was 43.8% in males and 27.1 in females. Prevalence of abdominal obesity (waist circumference >94 cm in males, >80 cm in females) was 1.6 % and 11.4 % for males and females respectively. Proportion of overweight (BMI 25.0+) was 3.6%.

CONCLUSION

Prevention programs and measures should be emphasized for the control of tobacco and hypertension in general, and central obesity in females, as far as rural population of Bangladesh is concerned.

Smokeless tobacco and cardiovascular disease

Various forms of smokeless tobacco (mainly snuff and chewing tobacco) cause an immediate increase in heart rate and blood pressure, but regular users of smokeless tobacco do not have permanent changes of heart rate or blood pressure when not exposed to tobacco. Cardiac output during workload and maximal working capacity are unaffected. Users of smokeless tobacco usually do not have the biochemical stigmata that regular smokers have. Thus, the scientific literature suggests that they are similar to non-tobacco users in terms of levels of hemoglobin/hematocrit, leukocytes, antioxidant vitamins, fibrinogen, components of the fibrinolytic system, C-reactive protein, and thromboxane A2 production. Two studies have found that snuff users, as opposed to smokers, do not have increased intima-media thickness or atherosclerotic lesions when investigated by ultrasound. Results on the risk for myocardial infarction have provided conflicting evidence, 2 case-control studies showing the same risks as in non-tobacco users and one cohort study showing an increased risk for cardiovascular death. In all, the use of smokeless tobacco (with snuff being the most studied variant) involves a much lower risk for adverse cardiovascular effects than smoking does. Whether or not the apparent risk reduction is a useful strategy to help inveterate smokers to quit is a matter of debate, as are the public health effects of a high prevalence of snuff use in some populations.

Prevention of coronary heart disease in south Asia

The great increase in rates of cardiovascular disease in developing countries will probably have grave implications for south Asia, which houses nearly a quarter of the world's population. Several factors might contribute to this effect, such as increased susceptibility of south Asian people to cardiovascular disease, unrecognised targets for preventive interventions, and restricted access to high-cost tertiary cardiovascular care for economically disadvantaged communities. Furthermore, prevention and control of cardiovascular disease does not feature prominently in the health care agendas of south Asian countries. To address these issues, therefore, a multifaceted approach is needed, which should include epidemiological studies to fill in the gaps in knowledge. Additionally, political, social, cultural, and economic issues need to be considered in prevention and control of these diseases, to identify and address key limitations and opportunities specific to the region. A set of recommendations outlining the approach is crucial.

Oral spit tobacco: addiction, prevention and treatment

The prevalence of smokeless tobacco is significant and reaches as high as 17% past month use in white males aged 18-25. Smokeless tobacco use is of concern because of the potential for addiction and the associated negative health consequences. This article reviews the basis for addiction to smokeless tobacco, examining the nicotine content in smokeless tobacco products, pharmacokinetics, psychoactive effects, tolerance, and withdrawal. It also explores the negative health consequences which include a number of oral pathologies and increased cardiovascular risk factors. Furthermore, it examines the factors associated with the initiation of smokeless tobacco use, and the current prevention programs that address these factors. Current smokeless tobacco treatment approaches are also discussed as well as predictors for abstinence. Finally, the future directions are discussed in light of the limited amount of research that has been conducted in the smokeless tobacco area, particularly related to prevention and treatment.

Effects of snuff on regional blood flow to the cheek and tongue of anesthetized dogs

Regional blood flow to the cheek and tongue of anesthetized dogs was measured before and after application of six different doses of snuff (3.12 to 100 mg/kg body weight) to the right cheek. Dose-independent vasodilation was observed at the site of application, whereas dose-dependent vasoconstriction was observed contralaterally. Aortic, central venous, and ventricular pressures were significantly increased (p < 0.05) at the higher doses. Plasma nicotine concentrations increased stepwise with dose.

Ergolytic drugs in medicine and sports

Just as drugs that enhance exercise capacity and/or athletic performance are often called "ergogenic," drugs that impair these functions can be termed "ergolytic." Today's athletes hear too much about the former and too little about the latter. Ergolytic drugs used today by certain athletes include alcohol, marijuana, smokeless tobacco, cocaine, antihypertensives, eye drops, and diuretics. Some antidepressants, too, can be ergolytic, as well as some antihistamines and other common drugs--even caffeine--in some settings, for some people. Internists can help their fitness-minded patients by educating them about ergolytic drugs and by tailoring their management to foster peak performance at work and play.

Tobacco and myocardial infarction: is snuff less dangerous than cigarettes?

OBJECTIVE

To estimate the risk of myocardial infarction in snuff users, cigarette smokers, and non-tobacco users in northern Sweden, where using snuff is traditional.

DESIGN

Case-control study.

SETTING

Northern Sweden.

SUBJECTS

All 35-64 year old men who had had a first myocardial infarction and a population based sample of 35-64 year old men who had not had an infarction in the same geographical area.

MAIN OUTCOME MEASURE

Tobacco consumption (regular snuff dipping, regular cigarette smoking, non-tobacco use) and risk of acute myocardial infarction.

RESULTS

59 of 585 (10%) patients who had a first myocardial infarction and 87 of 589 (15%) randomly selected men without myocardial infarction were non-smokers who used snuff daily. The age adjusted odds ratio for myocardial infarction was 0.89 (95% confidence interval 0.62 to 1.29) for exposure to snuff and 1.87 (1.40 to 2.48) for cigarette smoking compared with non-tobacco users, showing an increased risk in smokers but not in snuff dippers. Regular cigarette smokers had a significantly higher risk of myocardial infarction than regular snuff dippers (age adjusted odds ratio 2.09; 1.39 to 3.15). Smoking, but not snuff dipping, predicted myocardial infarction in a multiple logistic regression model that included age and level of education.

CONCLUSIONS

In middle aged men snuff dipping is associated with a lower risk of myocardial infarction than cigarette smoking.

Use of smokeless tobacco: blood pressure elevation and other health hazards found in a large-scale population survey

Health hazards associated with the use of smokeless tobacco were evaluated in a cross-sectional study of 97,586 Swedish construction workers undergoing health examinations in 1971-74. All users of smokeless tobacco only (5014 subjects) and all exclusive smokers of > or = 15 cigarettes daily (8823 subjects) were compared with all non-users of any tobacco (23,885). Both smokeless tobacco users and smokers showed higher prevalences of circulatory and respiratory disorders. Hypertension was most common in smokeless tobacco users. In the 45- to 56-years age group, the odds ratio for a diastolic blood pressure of > 90 mmHg was 1.8 (95% CI, 1.5-2.1), and for a systolic blood pressure > 160 mmHg, 1.7 (95% CI, 1.3-2.1). Smokers showed the lowest prevalence of hypertension. Disability pensions due to cardiovascular disease were nearly 50% more frequent in both smokeless tobacco users and smokers. These findings indicate that an increased cardiovascular risk is also associated with the use of smokeless tobacco.

Smokeless tobacco, cardiovascular risk factors, and nicotine and cotinine levels in professional baseball players

BACKGROUND

The use of smokeless tobacco (ST), which has increased in popularity over the past 2 decades, results in considerable systemic exposure to nicotine. Nicotine might contribute to atherosclerosis by an effect on cardiovascular risk factors.

METHODS

The effects of ST use on cardiovascular risk factors and cotinine and nicotine levels were studied in 1061 professional baseball players during spring training in 1988 and 1989.

RESULTS

Of the study participants 477 (45%) were users. ST use was more common among Whites (55%) than among Blacks (29%) or Hispanics (21%), and users reported heavier consumption of alcohol (p less than .001) and had higher mean serum caffeine levels (p less than .001) than nonusers. ST users did not differ from nonusers in adjusted levels of systolic and diastolic blood pressure, pulse, and total or HDL-cholesterol. Among ST users, participants using snuff had higher mean serum cotinine levels than those who used chewing tobacco (p less than .001). There was no association between serum cotinine levels and adjusted levels of any cardiovascular risk factor studied. However, higher diastolic blood pressures were associated with higher mean serum nicotine levels (p = .02).

CONCLUSIONS

Smokeless tobacco use has at most a modest effect on cardiovascular risk factors in young physically fit men.

Nicotine intake and dependence in Swedish snuff takers

Two studies examining nicotine intake in users of Swedish moist oral snuff are reported. Absorption form a single pinch (2 g) in ten users after overnight abstinence was fairly rapid. The increment in plasma nicotine concentrations averaged 9.9 ng/ml (SD 6.5) after 10 min and peaked at 14.5 ng/ml (SD 4.6) shortly after discarding at 30 min. Among groups of habitual snuff takers (n = 27) and cigarette smokers (n = 35) studied on a day of normal snuffing/smoking, peak blood nicotine levels after use were similar [averaging 36.6 ng/ml (SD 14.4) and 36.7 ng/ml (SD 16.1), respectively], but there was a tendency to higher cotinine levels in the snuffers (399.2 ng/ml versus 306.3 ng/ml). The snuff takers and cigarette smokers reported similar levels of subjective dependence on tobacco. Epidemiological study of Swedish snuff users could clarify whether the cardiovascular risks of tobacco are attributable to nicotine or to other smoke components, as in their case nicotine intake is not accompanied by combustion products.

Oral leukoplakia and adolescent smokeless tobacco use

The recent increase in smokeless tobacco (ST) use has prompted investigators to assess the health effects of ST use. This study attempted to evaluate the prevalence of oral leukoplakia among adolescent users and to determine factors associated with its presence. During their annual physical examination, 1116 teenaged football players (567 black, 546 white) answered a 34-question survey and received an oral screening examination. Results indicated that 0.5% of nonusers, 1.5% of previous users, and 13% of current users had clinically evident oral leukoplakia. Factors statistically associated with higher leukoplakia rates included history of ST use, regular ST use, years of ST use, and the weekly quantity consumed. Factors not associated included use of alcohol, use of cigarettes, type of ST used, and hours of ST use. One brand of snuff was found to be associated with a relative risk of leukoplakia higher than that of another brand of snuff. Overall, in ST users oral leukoplakia was six times more likely to develop than in nonusers. Earlier ages of ST use may lead to greater periods of use (in years) and to possible increases in deleterious long-term health effects in current adolescents.

Health-risk warning labels on smokeless tobacco products: are they effective?

This study investigated whether adolescents attend to the health-risk warnings placed on smokeless tobacco products and the impact the warnings have on intentions to use such products. The subjects (86 male and 106 female high school students) viewed illustrations of five consumer products, including a can of oral snuff and a pouch of chewing tobacco displaying one of the three required health warnings or no warning, and then indicated via questionnaire the likelihood that they would use each of the products. Fewer than half of the subjects (43.4%) exposed to the warnings recalled seeing them, and approximately a third of those who saw the warnings (32.2%) recalled the content of the message. Males were significantly better than females (p less than .02) at recalling the content. A series of 2 x 4 (Sex x Warning Label) ANOVAs revealed that the warning labels had no significant effect on subjects' ratings of whether they would use smokeless tobacco in the future. These results question the effectiveness of the warning labels for discouraging adolescent smokeless tobacco use.

P.L. 99-252--implications for dentists and their clinical practice

This paper is one of a series attempting to determine the impact of Public Law 99-252, the Comprehensive Smokeless Tobacco Health Education Act of 1986, on decreasing smokeless tobacco use. Potential indicators are discussed that could be used by the dental profession to determine the efficacy of the profession's involvement in existing and future prevention and cessation efforts relative to this law. In this review, six major areas are considered for measuring declines in smokeless tobacco use relative to the role of the dental health practitioner. These areas encompass the following: (1) the dental profession's knowledge of smokeless tobacco health hazards, (2) dental practitioners' involvement in measuring changes in use patterns, (3) the influence dentists have with their patients and community in decreasing smokeless tobacco use, (4) the general attitude and intention to quit on the part of dental patients, (5) active governmental involvement efforts, and (6) health effects of smokeless tobacco that might be used for identifying decreasing smokeless tobacco use. Within each of these six broad categories, more specific indicators for measuring the impact of P.L. 99-252 relative to the dental profession were considered.

Effect of smokeless tobacco on the development of the CD-1 mouse fetus

The objective of this study was to examine the effect of an aqueous extract of smokeless tobacco (ST) on the development of the CD-1 mouse fetus. Three ST dosages were administered three times daily by gastric intubation during gestational days 1-17: 1 X ST equivalent to a dose of 4 mg nicotine/kg body weight, 3 X ST equivalent to 12 mg nicotine, and 5 X ST equivalent to 20 mg nicotine/kg body weight. Maternal plasma nicotine levels were determined 30 minutes after the second daily intubation at five different times during the gestational period. At these ST dosages, the weight gain of ST-treated dams was not significantly affected in comparison to treated controls, though the difference was significant (P less than .05) in comparison to untreated controls. The mean maternal plasma nicotine level for the low dosage (1 X) group was 99.0 ng/ml, which reasonably approximates human consumption levels. The 3 X ST and 5 X ST dosages produced higher nicotine plasma values, 398 ng/ml and 623 ng/ml, respectively, were considerably more toxic to the dams, and resulted in 18% and 31% maternal deaths. Fetal weights were reduced by 7.4% (P less than .001) in the highest ST dosage group (5 X), whereas at the 1 X and 3 X dosages fetal weight differences were not significantly different from treated controls. Resorptions increased in a dose-related manner (P less than .05), ranging from 4.7% in the 1 X, to 6.4% in the 3 X and 8.9% in the 5 X dosage compared to 3.2% in treated controls. External malformations were few and minor in extent. Internal malformations increased in a linear, dose-related manner (P less than .05). Placental weights were unaffected by ST. The results of skeletal examinations were inconclusive. Precocious ossification was seen in 60% and 70% of the parameters measured in the 1 X and 3 X dosage groups, respectively, in comparison to controls. In the 5 X ST group ossification levels were less than in controls for 30% of the parameters measured. Under these experimental conditions the lowest ST dosage (1 X) produced a negligible effect on the CD-1 mouse fetus and the dam. The highest ST dose (5 X) demonstrated embryotoxicity, growth retardation, few malformations, and maternal toxicity. The intermediate dose (3 X) showed a range of effects between the highest and lowest doses to both the fetus and the dam.

An interpretative review of smokeless tobacco research in the United States: Part II

This is the second part of a two-part series reviewing the published literature of smokeless tobacco in the United States. The article explores smokeless tobacco as a pharmacologically addicting substance, educational interventions designed to prevent use or help users quit, and outlines areas of future research.

Development of a validation test for self-reported abstinence from smokeless tobacco products: preliminary results

Using X-ray fluorescence spectrometry, 11 heavy elements at concentrations that are easily detectable have been identified in smokeless tobacco products. These concentrations were found to increase in cheek epithelium samples of the user after exposure to smokeless tobacco. This feasibility study suggests that the level of strontium in the cheek epithelium could be a valid measure of recent smokeless tobacco use. It also demonstrates that strontium levels become undetectable within several days of smokeless tobacco cessation. This absence of strontium could validate a self-report of abstinence from smokeless tobacco. Finally, the X-ray spectrum of heavy metal content of cheek epithelium from smokeless tobacco users could itself provide a visual stimulus to further motivate the user to terminate the use of smokeless tobacco products.

The interaction of alcohol and tobacco use in adolescents and young adults: Bogalusa Heart Study

Alcohol and tobacco usage patterns were assessed in 1,811 children and young adults, 12-24 years of age. The prevalence of cigarette smoking and alcohol consumption increased with age in all race and sex groups. Smokeless tobacco use (chewing tobacco and snuff) was primarily seen in white males with the highest prevalence rates in 12-15 year olds. Among white males who reported smokeless tobacco usage, 44% of the 12-17 year olds and 80% of the 18-24 year olds reported concurrent alcohol use. There was a significant interaction between alcohol consumption and cigarette smoking in all four race-sex groups (p less than 0.001). Given the potential synergistic relationship between ethanol and tobacco products on oral and upper gastrointestinal tract cancer, as well as between smoking and cardiovascular disease, the long term effects from these behaviors could be troublesome. Since healthy lifestyles are established in youth, early intervention on alcohol and tobacco use is needed to prevent the future morbidity and mortality from cancer and cardiovascular disease.

Smoking and mechanisms of cardiovascular control

In humans short-term administration of nicotine, whether by smoking or intravenous injection, will typically raise blood pressure by 5 to 10 mm Hg and heart rate by 10 to 25 bpm. Smoking causes reduced myocardial contractility and left ventricular function in patients with angina pectoris or heart failure. Nicotine's mechanism of action is more complex than the classic concept of nicotinic ganglionic stimulation can account for. Nicotine exerts a potent pressor effect in the ventral lateral medulla (C-1 area). Little current data are available documenting the efficacy of centrally acting antihypertensive agents and converting-enzyme inhibitors with regard to preventing nicotine's acute cardiovascular effects.

An interpretative review of smokeless tobacco research in the United States: Part I

The first part of a two-part series reviewing the published literature of smokeless tobacco in the United States and concomitant health effects associated with its use. This article delineates the current status of its prevalence, behavioral psychosocial factors associated with use, and review of the negative health effects associated with regular use.

Screening for smokeless tobacco-associated lesions: recommendations for the dental practitioner

The increasing use of smokeless tobacco and the accumulating list of associated health hazards including cancer and cardiovascular effects should be of concern to the dentist. This study documents both concern from patients' perceptions and clinical examinations of their smokeless tobacco-associated lesions. Implications for the dentists' practice among adolescents and young adults are discussed.

The prevalence of smokeless tobacco use among adolescent male athletes

In assessing the prevalence and perceptions of use of smokeless tobacco among adolescent male athletes, several findings have public health implications. Almost a third of the sample had tried smokeless tobacco and 8% were current users. Racial differences between blacks and whites were remarkable. Differences in income strata and urban/rural settings were not significant. Peer influence was the major factor that initiated smokeless tobacco use. Abnormal mucosal findings were much more prevalent in those who had dipped smokeless tobacco than in those who had not. Most significant was a prevalence of oral leukoplakia in 5.2% of those who had ever dipped, which was 50 times that of nondippers. Using smokeless tobacco for more than 2 years or using more than three tins per week seemed to be of possible predictive value regarding the incidence of oral leukoplakia. Fifteen percent of current users had observable leukoplakia. Components necessary for effective intervention/prevention programs were elucidated with an emphasis on an increased role by dentists and other health professionals.

Effect of smokeless tobacco on the development of the CD-1 mouse fetus

The objective of this study was to examine the effect of smokeless tobacco (ST) on the development of the CD-1 mouse fetus. ST was administered continuously via Alzet osmotic minipumps during the critical gestational days 7-14 and 6-13. Two ST dosages were administered, 3.2 mg/ml (Dosage I) and 6.4 mg/ml (Dosage II), which yielded plasma nicotine levels within the range comparable to those of an average ST user or smoker (36.0 ng/ml). Plasma nicotine levels were maintained in the range of 29.4 +/- 4.8 ng/ml to 44.3 +/- 16.0 ng/ml for the Dosage I group of dams, and in the range of 34.6 +/- 10.9 ng/ml of 75.5 +/- 19.9 ng/ml for the Dosage II group of dams. The main effect on the fetus was weight reduction, with Dosage I producing a tendency toward weight reduction (p = .08). Dosage II produced a significant 8.6% weight reduction from normal (p less than .0001) and an increase in fetal deaths (p less than .03). Dosage I produced an increase in the incidence of hemorrhages and supernumerary ribs, and a significant delay (p less than .05) in ossification of the supraoccipital bone, the sacrococcygeal vertebrae, and the bones of the forefoot and hindfoot. There were no significant differences between placental weights. Weights of dams were significantly reduced only at the higher ST exposure levels. We conclude that at plasma nicotine levels comparable to those of an average ST user, ST produces weight reduction, delayed ossification, and increase in hemorrhages and fetolethality in the CD-1 mouse fetus.

Personality traits of smokeless tobacco users and nonusers: a comparison

This study investigated the personality characteristics of male university students who were either users or nonusers of smokeless tobacco. The hypotheses attempted to determine any differences in personality characteristics between users and nonusers of smokeless tobacco, and examine differences in personality characteristics according to the amount of smokeless tobacco used. A university sample of 289 males revealed 19% (55) prevalence of smokeless tobacco users. Each subject was administered Cattell's Sixteen Personality Factor Questionnaire and a demographic questionnaire. An analysis of variance revealed that smokeless tobacco users exhibited significant differences (p less than .01) in both personality characteristic A (more reserved, less outgoing socially) and personality characteristic I (self-reliant, less sentimental), and significant difference (p less than .05) in personality characteristic Q2 (more conforming, group dependent). No significant differences were noted in personality among persons who used varying amounts of smokeless tobacco.

Smokeless tobacco use by middle school males: a preliminary test of the reasoned action theory

This study identified psychosocial variables associated with smokeless tobacco use within the context of the reasoned action theory. One hundred twelve male students, ages ten-14, completed a questionnaire that operationalized components of the theoretical model. Multiple regression analyses revealed intention to use smokeless tobacco correlated significantly with attitude toward the behavior and perceived social pressure. As predicted by the theory, significant differences between those who intended to use smokeless tobacco and those who did not were found on several outcome and normative beliefs. The data support the utility of the theory as a means of explaining smokeless tobacco use. Future research recommendations are offered.

Learner characteristics associated with responses to film and interactive video lessons on smokeless tobacco

To determine college students' cognitive and affective responses to alternative technologies for presenting a lesson on smokeless tobacco, and to learn if responses to experimental conditions were associated with gender, ethnicity, tobacco-use practices, and the practices of significant others, 162 undergraduate students were randomly assigned to either a control group (questionnaire only) or one of two experimental groups. Experimental subjects viewed a videotape or an interactive video version of the lesson and then completed a questionnaire to ascertain knowledge and attitude. Each main effect was significant for knowledge about smokeless tobacco [experimental condition (P less than 0.001); gender (P less than 0.024); and ethnicity (P less than 0.003)]. The interactive video group demonstrated the most accurate and comprehensive recall. Neither gender nor ethnicity interacted significantly with experimental condition, indicating that the effect of experimental condition is constant across gender and ethnicity. Attitudes to instructional formats did not vary significantly as a function of experimental condition or gender, but were associated with ethnicity (P less than 0.034). Again, neither gender nor ethnicity interacted significantly with experimental condition, suggesting that attitudes reflect a generalized view toward content irrespective of presentation mode. Responses to both experimental conditions were quite favorable. Items about present and past experiences with tobacco, with the exception of the "Do you smoke?" item, were not associated with total cognitive score or attitude.

Prevalence and patterns of smokeless tobacco use in a southeastern university

The purpose of this study was to determine prevalence and patterns of use for tobacco products, especially, the use of smokeless tobacco among students at a university in the Southeastern United States. Six-hundred and thirty-two students, representing both sexes, participated in the survey, which elicited information regarding current and former use of tobacco products. Smokeless tobacco use was considerably more prevalent among male students than among female students; the reverse was true for cigarette smoking. Overall, the prevalence of tobacco use in this study indicates a need to begin health education programs regarding the adverse health effects of smokeless tobacco use with males and to revise smoking education programs to place more emphasis on female usage.

Implications of Smokeless Tobacco Use Among Athletes

In brief: This literature review delineates the current status of smokeless tobacco. It discusses the prevalence and terminology as well as periodontal effects, buccal mucosal and soft-tissue alterations, leukoplakia, cancer, carcinogenic components, hemodynamic alterations, and potential addiction. It is clear that physicians and dentists should discourage their patients from using smokeless tobacco. Young people particularly may be influenced by popular sports figures and celebrities who convey the erroneous impression that smokeless tobacco is harmless.

Changing trends of tobacco use in a teenage population in western Pennsylvania

Information on tobacco use was obtained from an anonymous questionnaire distributed to 609 8th, 9th, and 10th grade students in the Pittsburgh area. The data disclosed that 22 per cent of the girls and 11 per cent of the boys were smoking. However, 35 per cent of the young men reported using smokeless tobacco; snuff dipping (6 per cent), tobacco chewing (10 per cent), and snuff and/or tobacco chewing (19 per cent).