Cancers related to tobacco smoking

Tobacco smoking is the major cause of lung cancer. Cigarette smokers have a risk of lung cancer 10 to 15 times greater than nonsmokers. Tobacco and alcohol are the main risk factors for cancers of oral cavity, larynx, pharynx and oesophagus (cancers of the upper respiratory and upper digestive tract) and the effects of tobacco and alcohol are multiplicative. For these cancers, the risk associated with tobacco was about 2 to 4 among people who drink little or no alcohol. Risks of lung cancer and of cancers of the upper respiratory and upper digestive tract increase with an increasing number of cigarettes smoked per day and duration of smoking. Tobacco is also a risk factor for bladder cancer. Cigarette smoking is a possible contributory factor in the development of kidney, pancreatic and cervical cancers. Among males, lung cancer mortality increased regularly over time and today, lung cancer is the leading cause of death and illness from cancer. Substantial reductions in the number of deaths from tobacco-related cancers could be achieved if a large proportion of smokers stopped smoking.     

Prospective study of effect of switching from cigarettes to pipes or cigars on mortality from three smoking related diseases

OBJECTIVE: To estimate the extent to which cigarette smokers who switch to cigars or pipes alter their risk of dying of three-smoking related diseases-lung cancer, ischaemic heart disease, and chronic obstructive lung disease. DESIGN: A prospective study of 21520 men aged 35-64 years when recruited in 1975-82 with detailed history of smoking and measurement of carboxyhaemoglobin. MAIN OUTCOME MEASURES: Notification of deaths (to 1993) classified by cause. RESULTS: Pipe and cigar smokers who had switched from cigarettes over 20 years before entry to the study smoked less tobacco than cigarette smokers (8.1 g/day v 20 g/day), but they had the same consumption as pipe and cigar smokers who had never smoked cigarettes (8.1 g) and had higher carboxyhaemoglobin saturations (1.2% v 1.0%, P < 0.001), indicating that they inhaled tobacco smoke to a greater extent. They had a 51% higher risk of dying of the three smoking related diseases than pipe or cigar smokers who had never smoked cigarettes (relative risk 1.51; 95% confidence interval 0.96 to 2.38), a 68% higher risk than lifelong non-smokers (1.68; 1.16 to 2.45), a 57% higher risk than former cigarette smokers who gave up smoking over 20 years before entry (1.57; 1.04 to 2.38), and a 46% lower risk than continuing cigarette smokers (0.54; 0.38 to 0.77). CONCLUSION: Cigarette smokers who have difficulty in giving up smoking altogether are better off changing to cigars or pipes than continuing to smoke cigarettes. Much of the effect is due to the reduction in the quantity of tobacco smoked, and some is due to inhaling less. Men who switch do not, however, achieve the lower risk of pipe and cigar smokers who have never smoked cigarettes. All pipe and cigar smokers have a greater risk of lung cancer than lifelong non-smokers or former smokers.     

Benign symmetrical lipomatosis: Madelung''s disease

The relationship between smoking and bladder cancer risk was investigated using data from a case-control study conducted between January 1994 and July 1996 in Alexandria, Egypt. Cases were 151 males with incident, histologically confirmed invasive cancer of the bladder, and controls were 157 males admitted to hospital for acute, non-neoplastic, non-urinary tract, non-smoking-related conditions. With reference to never smokers, ex-smokers had a multivariate odds ratio (OR) of 4.4 [95% confidence interval (CI) 1.7-11.7] and current smokers of 6.6 (95% CI 3.1-13.9). The ORs were 5.4 for < 20 and 7.6 for > or = 20 cigarettes per day. After adjustment for cigarette smoking, the ORs were 0.8 for waterpipe and 0.4 for hashish smokers. The risk was significantly related to duration of smoking (OR of 16.5 for > 40 years), and inversely related to age at starting (OR of 8.8 for starting < 20 years), and inversely related to time since quitting smoking. Compared with never smokers who did not report a clinical history of schistosomiasis, the OR was 9.4 for smokers with a history of schistosomiasis, and 10.7 for smokers ever employed in high-risk occupations compared with non-smokers not reporting such a history. Thus, our results, while not giving indications of an increased bladder cancer risk with habits other than cigarette smoking, found a remarkably strong association with various measures of cigarette smoking that could explain 75% of bladder cancer cases among males from Alexandria. The prevalence of smoking was very low among women, and consequently tobacco was not a relevant risk factor for female bladder cancer.     

Smoking patterns and cancer of the oral cavity and pharynx: a case-control study in Uruguay

A case-control study of cancer of the oral cavity and pharynx was conducted in Uruguay, between 1992 and 1996. 425 patients microscopically diagnosed with squamous cell carcinoma of the oral cavity and pharynx were frequently matched on age, residence, and urban/rural status with 427 hospitalised controls. The study was restricted to males. Smokers of black tobacco cigarettes were associated with an increased risk of 12.1 (95% confidence interval (CI) 7.6-19.4), when compared with non-smokers after fitting a model which included the matching variables, birthplace, education, and total alcohol consumption. Lifelong smokers of hand-rolled cigarettes displayed an odds ratio (OR) of 8.7 (95% CI 5.6-13.4), compared with non-smokers. When smokers were excluded from the calculations, the OR for smokers of black tobacco cigarettes was 3.0 (95% CI 2.0-4.6), compared with smokers of blond tobacco cigarettes, after controlling for the same variables mentioned above, plus pack-years, years since stopping, and filter use. Hand-rolling appears to be less important than smoking black tobacco in this study (OR 1.6, 95% CI 0.9-2.5). Thus, smoking black tobacco cigarettes appears to be an important habit in oral and pharyngeal carcinogenesis.     

Notes on the intermediary form of incontinentia pigmenti

In a survey of a representative sample of 900 persons in Switzerland (excluding the Italian speaking parts comprising some 4-5 percent of the population), the smoking habits of the adult population were studied. Smokers were defined as persons smoking at least one cigarette or an equivalent weight of pipe tobacco or cigars per day. 51.8% of men and 29.0% of women over age 15 are smokers. Among male smokers of cigarettes only (42% of all men), over three quarters (77.6%) smoke ten cigarettes or more per day, i.e., a quantity found harmful to health; over one half (55.8%) smoke twenty or more cigarettes per day. Half of all female smokers smoke ten or more cigarettes, more than one in every four female smokers (28.8%) smoke twenty or more cigarettes per day. It is calculated that almost two thirds of all cigarettes sold in Switzerland are smoked by smokers of twenty or more cigarettes per day, and that almost three quarters are smoked by smokers of ten or more cigarettes. Among men, smoking habits are independent of social status, whereas among women, those with higher family incomes show more frequent smoking, but also more widespread cessation of smoking than with lower incomes. Thirty percent of adults having been smokers have given up the habit, so that among men and women above age 15, theree are now some 20% and 14% respectively, of ex-smokers. This corresponds to at least 700,000 former smokers in all of Switzerland. The trend to give up starts already in the group aged 15-24 (over 20% of men and women having ever smoked have given up) and becomes more marked with increasing age. A large part of male and female smokers would like to free themselves of the habit. 30% of male and 34% of female smokers indicate that they had tried seriously to stop smoking during the twelve months preceding the interview. Trying to give up was not significantly associated with intensity of smoking or social status. According to this survey, a majority of the population (57.6%) is in favor of reserving certain parts of restaurants to non-smokers, following the example of non-smokers-compartments in railway trains. In a situation where a non-smoker asks a co-worker in a closed room not to smoke, 78.3% take sides with the non-smoker, either by conceding to him a right to smoke-free air, or by demanding from the smoker to show consideration for the non-smoker. Only 10.9% demand from the non-smoker understanding for the smoker, or concede to the smoker a right to smoke at work. Women show more understanding for cause of the non-smoker than men. This difference is more marked among smokers and former smokers than among non-smokers. Inasmuch as the results of this study are comparable to those of earlier surveys conducted in Switzerland, ther is good agreement. The only exception is a significant increase of the proportion of former smokers in the past years.     

Tobacco and tobacco smoke

Epidemiologic studies have demonstrated a causal relation between smoking of cigarettes and cancer of the lung in man. Women smokers, cigar, and pipe smokers also face an increased risk for lung cancer. Prospective and retrospective studies have found a correlation between smoking of cigarettes, cigars, and pipes and cancer of the oral cavity, larynx, and esophagus and for cigarette smokers increased risks to develop cancer of the pancreas, kidney, and urinary bladder. Dose responses have been established between number of cigarettes smoked and cancer of the respiratory and upper digestive tract. Tobacco chewers face an increased risk for cancer of the mouth and esophagus. Tobacco smoke has induced tumors of the lung in the dogs and of the larynx of hamsters. The particulate matter of the smoke is carcinogenic to the skin of mice and rabbits, and the bronchi and connective tissue of rats. In tobacco smoke were identified tumor initiators, tumor promoters, cocarcinogens and organ specific carcinogens. Chewing tobacco is a tumor promoting agent and contains traces of tobacco specific and carcinogenic nitrosamines. Ten to 15 yr after giving up smoking the ex-smoker faces the same low risk to develop cancer of the upper digestive tract, the lung, the pancreas, and the urinary tract as the nonsmoker. It should be our goal, therefore, to prevent young people from starting the smoking habit and to convince the smoker to quit smoking. So far, we can report no success in terms of decreasing smoking habits among younger people. On the other hand, we can take satisfaction from the fact that antismoking propaganda has had an effect on college educated males, that among the population as a whole, there is a considerable number of exsmokers; that smoking cessation clinics do prove cost effective and if they were to become part of every health care center, they could help a large number of heavy smokers who cannot seem to stop smoking on their own. We can also report that there has been a significant reduction in the tar yield of American cigarettes, a reduction which we hope will continue; that the tumorigenic activity of tobacco as measured in animal studies, has decreased; and that as a consequence of the above, the risk of lung cancer and other tobacco-related cancers among smokers of these cigarettes is lower than in years past. It is unlikely that man will ever be able to inhale smoke components as harmless as unpolluted air, but as long as we have a society which accepts this habit and as long as people find satisfaction in smoking, we must work towards the day when tobacco-related cancers and other diseases will be reduced to a minimum. With the world wide coperation of the scientific community, the Departments of Agriculture, and the tobacco industry, it is our hope that this goal will be achieved.     

Detection of microbial pathogens in shellfish with multiplex PCR

This study investigated the effect of drinking tea or coffee on the lung cancer risk of male cigarette smokers in a case-control in Uruguay. Four hundred and twenty-seven lung cancer cases were frequency matched on age and residence with 428 hospitalized controls suffering from conditions unrelated to tobacco smoking and diet. Whereas coffee drinking had no effect on the lung cancer risk of the cigarette-smoking men in this study, black tea consumption decreased this risk. Heavy drinkers of tea (two or more cups of tea per day) were associated with a reduced risk of 0.34 (95% CI 0.14-0.84). This protective effect was more evident among Kreyberg I tumors (squamous cell and small cell) and among light smokers. Possible sources of bias and mechanisms of action are discussed.     

The surgical therapy of prostatic tumors]

A random sample of 26,000 Swedish women who were asked about their smoking habits in the early 1960s have now been followed for 26 years with respect to cancer incidence. Most findings regarding tobacco smoking and cancer from studies of men were confirmed also among the women. Elevated relative risk for current smokers compared with women who never smoked regularly were seen for cancers of the lung, upper aerodigestive sites, pancreas, bladder, cervix and all cancers combined, as well as a notably high relative risk for cancers of organs of the urinary tract other than kidney and bladder. Relative risk increased with dose, measured as grams of tobacco smoked per day, for cancers of the upper aerodigestive sites, lung, cervix, bladder, organs of the urinary tract other than kidney and bladder and all cancers combined. For cancers of the lung, bladder and cervix, there was an inverse relationship with age when starting to smoke tobacco. The reported inverse relationship between smoking and endometrial cancer could not be corroborated, nor was there any significant relationship between smoking and colorectal or breast cancer.     

Forward angle analyzing power in p

BACKGROUND: Independent carcinogenic effects of alcohol drinking and tobacco smoking as well as their interaction can be usefully studied in a population of heavy drinkers and smokers. METHODS: A hospital-based case-control study was conducted during 1972 to 1983 in a large Veterans hospital in East Orange, New Jersey. A total of 359 oral cavity-oropharynx cancer cases and 2280 controls were interviewed according to tobacco smoking, use of smokeless tobacco, alcoholic beverage, coffee and tea drinking, race, family origin, religion, and occupation as bartender. RESULTS: Odds ratio of oral cancer increased up to the level of 35 cigarettes per day and 21 whiskey equivalents per day: no further increase was found for higher level of exposure to either factor. A protective effect of quitting smoking was found, but the number of former smokers was small. No difference occurred in oral cancer risk according to type of alcoholic beverage drunk. An interaction effect compatible with a multiplicative model was found between the two exposures. Blacks were at lower risk than whites, and, in the latter group, individuals of Italian origin were at lower risk than individuals from northern or central European countries. CONCLUSIONS: Alcohol drinking and tobacco smoking were responsible for the majority of oral cancer cases in this population of US Veterans.     

Degradation of weathered oil by mixed marine bacteria and the toxicity of accumulated water-soluble material to two marine crustacea

From 1982 to 1984, the authors conducted a population-based case-control study of lung cancer in men and women nonsmokers in New York State. In-person interviews were completed for 437 lung cancer cases (197 never smokers, 240 former smokers) and 437 matched population controls. Cases and controls were asked to report any history of physician-diagnosed nonmalignant lung disease; cases were more likely than controls to report such a history. Statistically significant associations were found for emphysema (odds ratio (OR) = 1.94, 95% confidence interval (CI) 1.10-3.43), chronic bronchitis (OR = 1.73, 95% CI 1.10-2.72), and the combined endpoint of emphysema, chronic bronchitis, or asthma (OR = 1.82, 95% CI 1.26-2.63). After adjustment for active and passive tobacco smoke exposure, emphysema, chronic bronchitis, and asthma (each condition and the combined endpoint) were significantly associated with lung cancer risk. The risk was more marked for squamous cell carcinomas and for subjects who were diagnosed at older ages, and it remained significant when surrogate interviews were excluded. These results are consistent with the hypothesis that certain prior lung conditions increase the risk of lung cancer in men and women nonsmokers.     

Glutathione S-transferase mu1 and N-acetyltransferase 2 genetic polymorphisms and exposure to tobacco smoke in nonsmoking and smoking lung cancer patients and population controls

We conducted a case-control study to assess the risk of lung cancer in relation to genetic polymorphisms of the detoxifying enzymes glutathione-S-transferase mu1 (GSTM1) and N-acetyl transferase 2 (NAT2), focusing on never-smokers, women, and older people. The study base consisted of persons > or =30 years of age in Stockholm County from 1992 to 1995. We recruited never-smoking lung cancer cases and a sex- and age-matched sample of ever-smoking cases at the three county hospitals mainly responsible for diagnosing and treating lung cancer. A total of 185 cases (25.4% men; 47.6% never-smokers) and 164 frequency-matched population controls (28.7% men; 48.2% never-smokers) supplied blood for genotyping. Detailed information was collected by interview on active and passive smoking, occupations, residences, and diet. The overall odds ratio (OR) for lung cancer associated with the GSTM1 null (GSTM1-) versus GSTM1+ genotype was 0.8 [95% confidence interval (CI), 0.5-1.2], with an OR close to unity among smokers, and lower ORs suggested among never-smokers. For NAT2 slow versus rapid acetylator genotypes, the OR was 1.0 (95% CI, 0.6-1.5) overall, which broke down into an increased risk for slow acetylators among never-smokers but an increased risk for rapid acetylators among smokers. Among never-smokers, a gene interaction was suggested, with combined slow acetylator and GSTM1+ genotype conferring particularly high risk (OR = 3.1; 95% CI, 1.1-8.6), but no clear pattern emerged among smokers. A detailed analysis among smokers showed no interaction between pack-years of smoking and the GSTM1 genotype but suggested a steeper increase in risk with increasing pack-years of smoking exposure for rapid than for slow acetylators. Our results do not support a major role for the GSTM1 genetic polymorphism as a risk factor for lung cancer among smokers or nonsmokers. There was, however, some suggestion that the slow acetylator genotype may confer an increased risk among never-smokers and that the rapid acetylator genotype interacts with pack-year dose to produce a steeper risk gradient among smokers.     

A model for the effect of cigarette smoking on lung cancer incidence in Connecticut

Population based data on smoking history derived from NCHS surveys were used to develop a model for lung cancer incidence in Connecticut. Trends in smoking prevalence suggest that, while the prevalence in men increased earlier than women, more male smokers have quit than their female counterparts. These trends in smoking prevalence suggest striking gender differences in a period effect for the smoking prevalence. Estimates of the proportion of current smokers, ex-smokers, and the mean duration of smoking were used in a model for the lung cancer incidence rates. The form for the relationship between smoking history and the incidence rate for these subgroups was based on information from cohort studies. The models represented a mixture of the smoking subgroups where the effect of smoking was considered to be either a multiplicative effect on the underlying age distribution, or a separate effect in which the level of exposure was the sole contribution to risk among smokers. The multiplicative model explained more than 80 per cent of the deviance for the period and cohort effects, while the non-multiplicative model could only account for trends in females. Hence, these results suggest that a sizeable portion of the period and cohort contributions to the lung cancer incidence trends in Connecticut can be attributed to the multiplicative model that utilizes this smoking information, although the lack of more detailed information is a limiting factor in developing the model.     

Regular smokers, lifetime very light smokers, and reduced smokers: Comparison of psychosocial and smoking characteristics in women.

This study compared stable very light smokers ([VLS]; less than 6 cigarettes a day) with regular smokers ([RS]; greater than 14 cigarettes a day) in a cohort of women followed up for 1 yr. The VLS showed evidence of inhaling the cigarette smoke. They were not novice smokers, nor were they under particular pressure to limit their smoking. Among the 61 VLS, 34 had at one time smoked more than 10 cigarettes per day. These "reduced smokers" were broadly similar to the lifetime VLS, who differed from RS in several important respects. In a multiple logistic regression, education and smoking patterns in relatives were independently associated with very light versus regular smoking. Familial factors and personal resources may protect against dependence among those who use tobacco. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Alpha-Tocopherol and beta-carotene supplements and lung cancer incidence in the alpha-tocopherol, beta-carotene cancer prevention study: effects of base-line characteristics and study compliance

BACKGROUND: Experimental and epidemiologic investigations suggest that alpha-tocopherol (the most prevalent chemical form of vitamin E found in vegetable oils, seeds, grains, nuts, and other foods) and beta-carotene (a plant pigment and major precursor of vitamin A found in many yellow, orange, and dark-green, leafy vegetables and some fruit) might reduce the risk of cancer, particularly lung cancer. The initial findings of the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study (ATBC Study) indicated, however, that lung cancer incidence was increased among participants who received beta-carotene as a supplement. Similar results were recently reported by the Beta-Carotene and Retinol Efficacy Trial (CARET), which tested a combination of beta-carotene and vitamin A. PURPOSE: We examined the effects of alpha-tocopherol and beta-carotene supplementation on the incidence of lung cancer across subgroups of participants in the ATBC Study defined by base-line characteristics (e.g., age, number of cigarettes smoked, dietary or serum vitamin status, and alcohol consumption), by study compliance, and in relation to clinical factors, such as disease stage and histologic type. Our primary purpose was to determine whether the pattern of intervention effects across subgroups could facilitate further interpretation of the main ATBC Study results and shed light on potential mechanisms of action and relevance to other populations. METHODS: A total of 29,133 men aged 50-69 years who smoked five or more cigarettes daily were randomly assigned to receive alpha-tocopherol (50 mg), beta-carotene (20 mg), alpha-tocopherol and beta-carotene, or a placebo daily for 5-8 years (median, 6.1 years). Data regarding smoking and other risk factors for lung cancer and dietary factors were obtained at study entry, along with measurements of serum levels of alpha-tocopherol and beta-carotene. Incident cases of lung cancer (n = 894) were identified through the Finnish Cancer Registry and death certificates. Each lung cancer diagnosis was independently confirmed, and histology or cytology was available for 94% of the cases. Intervention effects were evaluated by use of survival analysis and proportional hazards models. All P values were derived from two-sided statistical tests. RESULTS: No overall effect was observed for lung cancer from alpha-tocopherol supplementation (relative risk [RR] = 0.99; 95% confidence interval [CI] = 0.87-1.13; P = .86, logrank test). beta-Carotene supplementation was associated with increased lung cancer risk (RR = 1.16; 95% CI = 1.02-1.33; P = .02, logrank test). The beta-carotene effect appeared stronger, but not substantially different, in participants who smoked at least 20 cigarettes daily (RR = 1.25; 95% CI = 1.07-1.46) compared with those who smoked five to 19 cigarettes daily (RR = 0.97; 95% CI = 0.76-1.23) and in those with a higher alcohol intake (> or = 11 g of ethanol/day [just under one drink per day]; RR = 1.35; 95% CI = 1.01-1.81) compared with those with a lower intake (RR = 1.03; 95% CI = 0.85-1.24). CONCLUSIONS: Supplementation with alpha-tocopherol or beta-carotene does not prevent lung cancer in older men who smoke. beta-Carotene supplementation at pharmacologic levels may modestly increase lung cancer incidence in cigarette smokers, and this effect may be associated with heavier smoking and higher alcohol intake. IMPLICATIONS: While the most direct way to reduce lung cancer risk is not to smoke tobacco, smokers should avoid high-dose beta-carotene supplementation.     

Impact of expenditures for veterinary services and medical supplies on dairy farm productivity and profitability

OBJECTIVES: This study was undertaken to explore smoking patterns and attitudes that influence smoking cessation and relapse among African Americans. METHODS: Baseline data from eight Community Intervention Trial for Smoking Cessation (COMMIT) sites were analyzed. RESULTS: Compared with Whites, African Americans who smoke less than 25 cigarettes per day were 1.6 times more likely to smoke within 10 minutes of awakening (a behavioral indicator of nicotine dependence), adjusting for education, age, and gender (OR = 1.2 for heavier smokers). African Americans reported a stronger desire to quit smoking and reported serious quit attempts in the past year. African Americans favored tobacco restrictions (they were 1.8 times more likely than Whites to view smoking as a serious community problem, 1.7 times more likely to favor restrictions on cigarette vending machines, and 2.1 times more likely to prohibit smoking in their car). African Americans were lighter/moderate, menthol smokers. CONCLUSIONS: African Americans find smoking socially unacceptable and are strongly motivated to quit, but their "wake-up" smoking may indicate high nicotine dependence, making abstinence difficult even for lighter smokers.     

The effects of smoking on bone mass and the rates of bone loss among elderly Japanese-American men

Bone density and bone loss rates were examined among Japanese-American men categorized as current cigarette smokers, past smokers, and nonsmokers. The design included a retrospective study of smoking and bone density and a prospective study of current smoking and bone loss rates. The mean length of follow-up was 5 years; the setting was the island of Oahu. The subjects included 1303 men in the Hawaii Osteoporosis Study, 51-82 years old at their initial examination. Twenty percent were current smokers, 45% past smokers, and 35% had never smoked. Their bone density was measured at the distal and proximal radius and calcaneus using single photon absorptiometry. Compared with never smokers, current and past smokers had significantly lower bone density, especially in the predominantly cancellous calcaneus (4.8 and 4.3% lower, respectively) and partially trabecular distal radius (1.8 and 3.3% lower, respectively). The magnitude of the smoking effect was linked strongly to the duration of smoking and also to the number of cigarettes smoked. Bone loss rates subsequent to the initial measurement were greater in the current smokers than the never smokers (20.5, 27.2, and 9.7% greater at the calcaneus, distal, and proximal radius, respectively) but the differences did not achieve significance. Smokers of more than one pack per day had 32.0, 77.6, and 30.7% greater loss rates than never smokers in these same sites; the difference achieved significance at the distal radius. The results from the distal radius suggest that these smokers may increase their fracture risk 10-30% per decade of smoking. The adverse effects of smoking appeared to be greater in cancellous than cortical bone.     

A population study of low-rate smokers: Quitting history and instability over time.

This study used 1 longitudinal and 2 cross-sectional population surveys to compare stability of low-rate daily smokers (less than 5 cigarettes per day) with other daily smokers and occasional smokers. Few low-rate smokers maintained consumption level; 36% retained smoking status after 20 months, compared with 82% and 44% for regular daily and occasional smokers, respectively. In a dynamic process, established smokers quit smoking and/or modified (decreased or increased) consumption. Low-rate and occasional smokers quit at higher rates than regular daily smokers (odds ratios 3:1) but were replenished by new members, many converted from regular daily smokers. The overall trend is an increasing proportion of low-consumption smokers while smoking prevalence declines. The dynamic process has implications for tobacco control efforts and for addiction theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relation of cigarette smoking to non-Hodgkin's lymphoma among middle-aged men

Because of previous inconsistencies in the observed relation of cigarette smoking to non-Hodgkin's lymphoma, this association was investigated in the Selected Cancers Study, a population-based case-control study of 1,193 non-Hodgkin's lymphoma cases and 1,903 controls, conducted between 1984 and 1988. Study subjects were men, and the median age of non-Hodgkin's lymphoma cases was 50 years (range, 32-60 years). As compared with the risk among men who had never smoked cigarettes, the risk among ever smokers was not increased (odds ratio (OR) = 1.05, p approximately 0.50), but the risk was significantly elevated among men who reported smoking > or = 2 1/2 packs per day and among men who had smoked for 30-39 years (OR = 1.45 in each group, p < 0.05). The estimated odds ratio among the 350 heavy smokers (> or = 50 pack-years) was 1.41 (95% confidence interval 1.08-1.85) after controlling for educational achievement, various occupational and medical exposures, and other potential confounders. The observed associations, however, tended to vary by age, with the odds ratio among heavy smokers decreasing from 2.8 among 32- to 44-year-olds to 1.1 among men over 55 years of age. These age-related differences, which may account for some of the inconsistencies seen in previous studies of cigarette smoking and non-Hodgkin's lymphoma, should be considered in future investigations.     

Frontopolar ictal epileptiform discharges on scalp electroencephalogram in temporal lobe epilepsy

OBJECTIVE: To determine the prevalence of the smoking habit among Mexican physicians as well as some of their attitudes and information on specific issues concerning smoking. MATERIAL AND METHODS: In 1993, a survey was carried out among 3,568 physicians of the three major official health care institutions in Mexico City. A questionnaire designed for The Mexican National Survey of Addictions (ENA 1993) was used. Prevalence of cigarette smoking, age of onset, number of cigarettes per day; also information and attitudes concerning smoking were assessed. RESULTS: The mean age was 37, 66% were males. Of the 3,488 (98%) surveyed, 26.9% were smokers (62% daily), 20.6% were ex-smokers and 52.5% non-smokers. There were differences related to age and sex (p < 0.05). Of daily smokers, 36% smoked between 1 and 5 cigarettes. There was a significant trend among ex-smokers that linked the time they had ceased smoking with the fear to start smoking again. Physicians were well informed of the relationship between cigarette smoking and lung cancer. Over 80% considered tobacco an addictive drug but only 65% were in favor of banning smoking from their workplaces and over 10% were not aware that it is forbidden to smoke inside health care facilities. CONCLUSIONS: These results differ from other studies that find the prevalence of smoking among physicians lower than in the general population. Our study revealed a greater prevalence of the smoking habit among female physicians and the number of cigarettes smoked per day was greater than in the general population regardless of sex.     

Smoking and lung function

In a cross-sectional survey of 3 separate communities, we studied the white residents 7 year of age and older in order to determine the relation between cigarette smoking and lung function. We identified 2,817 nonsmokers, 664 ex-smokers, and 1,209 smokers who were further classified as light smokers (1 to 20 cigarettes per day) and heavy smokers (greater than 20 cigarettes per day). Residual lung function (observed-predicted) was examined in these groups for forced expiratory volume in one second (rFEV1) and for maximal expiratory flow rates at 50% and 25% of the vital capacity (rVmax50% and rVmax 25%). Mean residuals by sex, age, and smoking category were compared and revealed an increasing progression of lung function loss with advancing age in males and females in all smoking categories. These age-related trends were due primarily to the amount smoked by persons in each group. The age of onset of these abnormalities was found to be as early as the age group 15 to 24 yr. Abnormalities were greater in smokers than ex-smokers, even when the amount smoked was taken into account. This is suggested improvement in lung function after cessation of smoking. Men and women were found to experience the same relative degree of gain. Also, the contribution of the various smoking habits to lung function loss was assessed using regression analyses and accounted for no more than 15% of the variation of the residual lung function. Combinations of variables were found to explain only slightly more variation than a single variable. The two most important variables were duration of smoking and pack-years. Inhalation and use of filters were not significant. Although the same amount of variation explained by the smoking variables after accounting for age, height, weight, and sex was small, this variation accounted for almost all of the decrease, over age, in residual lung function for smokers and ex-smokers.