Effects of second-hand smoke and gender on infarct size of young rats exposed in utero and in the neonatal to adolescent period

OBJECTIVES

We sought to assess the effects of second-hand smoke (SHS) and gender on infarct size in young rats exposed in utero or in the neonatal to adolescent period, or both.

BACKGROUND

We previously demonstrated that exposure to SHS increases infarct size in a rat model of ischemia and reperfusion, with a dose-response relation. These results are consistent with epidemiologic studies demonstrating that SHS increases risk of death from heart disease.

METHODS

Thirty-one pregnant female rats were randomly divided into two groups: those exposed to SHS and a control group (non-SHS). After 3 weeks, each rat had given birth to 10 to 12 rats. One hundred one neonatal rats were divided into four groups according to exposure to SHS in utero (SHSu) and randomized to SHS exposure in the neonatal to adolescent period (SHSna). After 12 weeks, all rats were subjected to 17 min of left coronary artery occlusion and 2 h of reperfusion.

RESULTS

Birth mortality was higher in the SHSu group than in the non-SHSu group (11.9% vs. 2.8%, p < 0.001). Body weight of neonatal rats at 3 and 4 weeks in the two SHSu groups was lower than that of rats in the two non-SHSu groups (p < 0.001). Exposure to SHSna increased endothelin-1 levels in plasma (p = 0.001). In all 70 young rats who survived the neonatal period, infarct size (Infarct mass/Risk area x 100%) was greater in the SHSna groups than in the non-SHSna groups (p = 0.005) and in the male groups than in the female groups (p < 0.001).

CONCLUSIONS

Exposure to SHS in the neonatal to adolescent period and male gender increased myocardial infarct size in a young rat model of ischemia and reperfusion. These results are consistent with epidemiologic studies demonstrating that SHS increases the health risk to neonates and adolescents.

The effect of ordinances requiring smoke-free restaurants and bars on revenues: a follow-up

OBJECTIVES

The purpose of this study was to extend an earlier evaluation of the economic effects of ordinances requiring smoke-free restaurants and bars.

METHODS

Sales tax data for 15 cities with smoke-free restaurant ordinances, 5 cities and 2 counties with smoke-free bar ordinances, and matched comparison locations were analyzed by multiple regression, including time and a dummy variable for the ordinance.

RESULTS

Ordinances had no significant effect on the fraction of total retail sales that went to eating and drinking places or on the ratio between sales in communities with ordinances and sales in comparison communities. Ordinances requiring smoke-free bars had no significant effect on the fraction of revenues going to eating and drinking places that serve all types of liquor.

CONCLUSIONS

Smoke-free ordinances do not adversely affect either restaurant or bar sales.

Short-term economic and health benefits of smoking cessation: myocardial infarction and stroke

BACKGROUND

Most analyses of the economic benefits of smoking cessation consider long-term effects, which are often not of interest to public and private policy makers. These analyses fail to account for the time course of the short-run cost savings from the rapid decline in risk of acute myocardial infarction (AMI) and stroke.

METHODS AND RESULTS

We estimate the time course of the fall in risk of AMI and stroke after smoking cessation and simulate the impact of a 1% absolute reduction in smoking prevalence on the number of and short-term direct medical costs associated with the prevented AMIs and strokes. In the first year, there would be 924+/-679 (mean+/-SD) fewer hospitalizations for AMI and 538+/-508 for stroke, resulting in an immediate savings of $44+/-26 million. A 7-year program that reduced smoking prevalence by 1% per year would result in a total of 63,840+/-15,521 fewer hospitalizations for AMI and 34,261+/-9133 fewer for stroke, resulting in a total savings of $3.20+/-0.59 billion in costs, and would prevent approximately 13,100 deaths resulting from AMI that occur before people reach the hospital. Creating a new nonsmoker reduces anticipated medical costs associated with AMI and stroke by $47 in the first year and by $853 during the next 7 years (discounting 2.5% per year).

CONCLUSIONS

Although primary prevention of smoking among teenagers is important, reducing adult smoking pays more immediate dividends, both in terms of health improvements and cost savings.

Chronic dietary L-arginine prevents endothelial dysfunction secondary to environmental tobacco smoke in normocholesterolemic rabbits

Our goal was to determine whether environmental tobacco smoke causes endothelial dysfunction in the absence of hypercholesterolemia and whether such an effect can be prevented by supplementation with L-arginine. Environmental tobacco smoke exposure is associated with an increase in coronary artery disease events and mortality. We have previously demonstrated that environmental tobacco smoke causes endothelial dysfunction and atherosclerosis in rabbits with diet-induced hypercholesterolemia and atherosclerosis and that chronic dietary L-arginine supplementation prevents this. The effects of L-arginine supplementation (2.25% solution ad libitum) and environmental tobacco smoke (smoking chambers for 10 weeks) were examined with a 2 x 2 design in 32 rabbits fed a normal diet. Acetylcholine, calcium ionophore A23187, and nitroglycerin-induced vasorelaxation were assessed in aortic rings precontracted with phenylephrine. Endothelial L-arginine levels were measured by chromatography. Chronic L-arginine supplementation increased serum (P < .001) and endothelial (P = .003) L-arginine levels. Environmental tobacco smoke reduced endothelium-dependent acetylcholine-induced relaxation, and L-arginine blocked this adverse effect (P = .04). Environmental tobacco smoke tended to increase phenylephrine-induced contraction (P = .06). Neither environmental tobacco smoke nor L-arginine influenced A23187-induced relaxation nor endothelium-independent nitroglycerin-induced relaxation. Endothelial dysfunction secondary to environmental tobacco smoke may occur in the absence of diet-induced hypercholesterolemia and atherosclerosis. Chronic dietary supplementation with a nitric oxide donor such as L-arginine offsets the endothelial dysfunction associated with environmental tobacco smoke in normocholesterolemic rabbits, possibly through substrate loading of the nitric oxide pathway.

Testosterone worsens endothelial dysfunction associated with hypercholesterolemia and environmental tobacco smoke exposure in male rabbit aorta

OBJECTIVES

To assess the effects of interaction of sex hormones, hypercholesterolemia (HC) and environmental tobacco smoke (ETS) exposure on endothelium-dependent relaxation, we examined vascular reactivity in vitro in an animal model of atherogenesis.

BACKGROUND

Animal and human studies indicate the presence of interactions between classic coronary artery disease risk factors and endothelium-dependent relaxation. Sex hormones have also been shown to influence release of endothelium-derived relaxing factor.

METHODS

New Zealand White rabbits were randomized to receive either an HC diet (n = 8) or ETS exposure plus HC diet (n = 8). Eight rabbits receiving a normal diet, without exposure to ETS, served as the control group. The HC diet consisted of 3% soybean oil and 0.3% cholesterol by weight over 13 weeks. The source of ETS was sidestream smoke of 4 cigarettes/15 min, 6 h/day, 5 days/week over 10 weeks in a smoking chamber. Rabbits were killed, and fresh aortic rings were harvested and maintained in oxygenated Krebs solution in an organ bath at 37 degrees C. Rings were precontracted with norepinephrine and exposed to acetylcholine in increasing doses, and isometric tension was recorded. Rings were also exposed to physiologic concentrations (1 nmol/liter) of either 17-beta-estradiol, testosterone or progesterone before pre-contraction with norepinephrine and relaxation with acetylcholine. Endothelium-independent relaxation was studied using nitroglycerin. The surface area of the ring covered by lipids was measured by Sudan IV staining.

RESULTS

HC and ETS significantly reduced endothelium-dependent relaxation (p = 0.01 and p < 0.0005, respectively) and caused atherogenesis (p < 0.0005 and p = 0.047, respectively) but did not affect endothelium-independent relaxation. Incubation with estradiol and estradiol plus progesterone did not influence endothelium-dependent relaxation. Testosterone reduced endothelium-dependent relaxation (p = 0.049) and augmented the endothelial dysfunction associated with ETS exposure and HC (p = 0.03).

CONCLUSIONS

Both HC and ETS are atherogenic and impair endothelial function but do not affect endothelium-independent relaxation. Physiologic levels of estradiol and estradiol plus progesterone do not affect endothelium-dependent relaxation. Physiologic levels of testosterone impair relaxation and augment the endothelial dysfunction associated with ETS exposure and HC.

Political realities of statewide smoking legislation: the passage of California's Assembly Bill 13

OBJECTIVE

To prepare a history of the enactment of California Assembly Bill 13 (AB 13), a state law prohibiting smoking in most workplaces passed in 1994, and to discuss its initial impacts.

METHODS

Data were gathered from open ended interviews with representatives of voluntary health organisations, local government organisations, and principal legislators involved in the process, as well as observers around the state who could provide insight into the legislative process. Information was also obtained from legislative hearings and debates, public documents, letters and personal communications, internal memoranda, and news reports.

RESULTS

The success of local tobacco control legislation in California led to a situation in which some health groups were willing to accept state preemption in order to attract the support of the state restaurant association for a bill. The decision to accept this preemption compromise was made by the state level offices of the voluntary health agencies without consulting the broader tobacco control community within California. In contrast, local tobacco control advocates did not accept this compromise, in part because of their belief that local legislation was a better device to educate the public, generate media coverage, and build community support for enforcement and implementation of clean indoor air and other tobacco control laws. Enactment of AB 13 was associated with a slowing of all local tobacco control legislation, including youth oriented laws.

CONCLUSIONS

Because its supporters initially doubted that AB 13 would pass, there was never an effort to reconcile the policy differences between state oriented and locally oriented tobacco control policies. This lack of consensus, combined with the political realities inherent in passing any state legislation, led to a bill with ambiguous preemption language which replaced the "patchwork of local laws" with a "patchwork of local enforcement."

Tobacco use is increasing in popular films

OBJECTIVE

To study the presentation of smoking in motion pictures.

DESIGN

This study examined tobacco use in a random sample of five of the top 20 grossing films each year from 1990-1996 and combined these data with our earlier study of tobacco use in films that covered 1960-1990.

MAIN OUTCOME MEASURES

Rate of tobacco use per minute of film, characters who are smoking, motivation to smoke.

RESULTS

The overall rate of tobacco use appears to have "bottomed out" in the 1980s and is now increasing back to levels observed in the 1960s. The presentation of tobacco use in films is increasingly discordant with reality, because tobacco use in the population continues to drop. Films continue to portray smokers as successful white males, although portrayal of smoking among women is increasing.

CONCLUSIONS

The gap between the representation of tobacco use in films and the reality of tobacco continues to widen, with the prevalence of smoking among lead characters four times the smoking prevalence among comparable individuals in society at large.

Question 1 tobacco education expenditures in Massachusetts, USA

BACKGROUND

In 1992, voters in Massachusetts (United States) approved Question 1, a state ballot initiative, which raised the state excise tax to provide funds for tobacco education.

OBJECTIVE

To examine Question 1 expenditures for tobacco-specific programmes in the 1994, 1995, 1996, and 1997 fiscal years.

DESIGN

This study examined trends in Question 1 expenditures. Data were collected from the Massachusetts Department of Public Health and the Massachusetts Department of Revenue for the 1994, 1995, 1996, and 1997 fiscal years.

MAIN OUTCOME MEASURES

The amount of spending on tobacco-specific programmes.

RESULTS

Excluding the 1994 fiscal year because the state allocated 18 months of new revenues, from the 1995 fiscal year to the projected 1997 fiscal year, the state will have spent 22% of Question 1 funds for tobacco-specific programmes. Question 1 expenditures for tobacco-specific programmes have declined by 15%, whereas Question 1 expenditures for the other programmes decreased only 0.4%.

CONCLUSIONS

The legislature has established a trend that has produced real reductions in Question 1 funding for tobacco education, which appears contrary to the mandate of the voters when they enacted Question 1 in 1992. These reductions undermine the effectiveness of tobacco-specific programmes that are an integral part of the Massachusetts Tobacco Control Programme. These results also highlight the fact that the initial compromises made after initiatives such as Question 1 are adopted have important long-term consequences for funding of tobacco control initiatives.

L-arginine decreases infarct size in rats exposed to environmental tobacco smoke

This study examined the effects of L-arginine on myocardial infarct size, hemodynamics, and vascular reactivity in environmental tobacco smoke (ETS)-exposed and non-ETS-exposed rats. We previously demonstrated that exposure to ETS increased myocardial infarct size in a rat model of ischemia and reperfusion. If reduced reperfusion was caused by endothelial cell damage and increased vascular tone, L-arginine (ARG) would increase nitric oxide and better protect the heart. Sixty Sprague-Dawley rats were randomly divided into four groups: ETS or non-ETS (control) with and without ARG (2.25% ARG in drinking water). The ETS groups were exposed to passive smoking (4 Marlboro cigarettes per 15 minutes, 6 hours a day) for 6 weeks. After 6 weeks, all rats were subjected to 35 minutes of left coronary artery occlusion and 120 minutes of reperfusion, with hemodynamic monitoring. Aortic rings were harvested to evaluate vascular reactivity. Average air nicotine, carbon monoxide, and total particulate concentrations were 1304 +/- 215 microgram/m3, 78 +/- 2.0 ppm, and 31 +/- .7 mg/m3 (mean +/- SEM) for the ETS-exposed rats. Infarct size (infarct mass/risk area x 100%) increased with ETS exposure but decreased significantly in the ETS-with-ARG group compared with the ETS-without-ARG group (42% +/- 6% vs 64% +/- 6%, mean +/- SEM; p = 0.043). The benefit of ARG was dependent on ETS exposure (ETS x ARG interaction, p = 0.043). There were no significant differences between groups in heart rate, systolic pressure, and rate-pressure product. ARG significantly decreased myocardial infarct size after ischemia and reperfusion in ETS-exposed rats. Neither the adverse effects of ETS on infarct size nor the blockage of this effect by ARG appears to be the result of ETS-induced alterations in hemodynamics.

On the influence of superstructure connection on implant preload: a methodological and clinical study

In a combined in vitro and in vivo study strain gauges were used to register the deformation in two terminal implant abutment cylinders, when connecting three different prosthetic appliances. The prosthetic constructions were placed on the abutments and fastened in vitro and in vivo by using different torque sequences. Furthermore, in the in vitro situation the three medial abutments were replaced by abutments which were 100 microns shorter. The results show that even if the prosthetic constructions were judged to have a good clinical fit, relatively large External Preloads were registered both in vitro and in vivo. No significant differences in axial force or in bending movement were found between the torque sequences in vivo. There were, however, significant differences in axial force as well as in bending moment in the in vitro experiment. When the shorter medial abutments were used in vitro, a change in the axial force of approximately 200 N was registered. The results confirm that the methodological approach used in this study is valid when evaluating preloads.

California's tobacco tax initiative: the development and passage of Proposition 99

In this case study, we describe and analyze the development and passage of California's tobacco tax initiative, Proposition 99, the Tobacco Tax and Health Promotion Act of 1988. We gathered information from published reports, public documents, personal correspondence, internal memorandums, polling data, and interviews with representatives from organizations that participated in the Proposition 99 campaign. Proposition 99 passed as a result of the efforts of a coalition of voluntary health agencies, medical organizations, and environmental groups. They organized a long-term effort by conducting essential polling, planning strategies, gaining media exposure, developing a coalition, and running a successful campaign to enact the tax by shifting the venue from legislative to initiative politics. To build the coalition that was needed to pass Proposition 99, public health proponents enlisted the help of medical organizations in exchange for additional revenue to be allocated to medical services. By shifting the venue from the legislature to the general public, advocates capitalized on public concern about tobacco and for youth and took advantage of the tobacco industry's low credibility. The passage of Proposition 99, despite a massive campaign against it by the tobacco industry, represents a milestone in the tobacco control and public health fields. From its passage in 1988 through 1993, tobacco use in California declined by 27 percent, which is three times faster than the United States average. As a result, Proposition 99 has served as a national model for other states and the federal government. Although allocation of tobacco tax revenues specifically to health education and prevention was a primary goal during the development and passage of Proposition 99, when the venue shifted back to the legislature for implementation, medical organizations successfully advocated illegal diversions of Proposition 99 tobacco control and research funds to medical services. Organizations seeking to enact Proposition 99-like tobacco tax increases must be prepared to mount aggressive campaigns to pass the initiative in the face of major tobacco industry opposition and then must continue to work to protect the program after passage by voters.

Tobacco information in two grade school newsweeklies: a content analysis

OBJECTIVES

This study compared tobacco-related articles from two elementary school publications, Weekly Reader and Scholastic News, published in 1989 through 1994.

METHODS

Articles for grades 4 through 6 were evaluated, and the publications were compared with each other. Also, issues of Weekly Reader published after acquisition by K-III, which is owned by the firm that formerly owned RJR Tobacco, were compared with the earlier ones.

RESULTS

Weekly Reader was less likely than Scholastic News to mention short-term consequences of smoking (32% vs 64%) or to give a clear "no-use" message (35% vs 79%). Weekly Reader was more likely to give the tobacco industry position (68% vs 32%). Post-K-III issues of Weekly Reader were less likely to provide a clear no-use message than earlier ones (62% vs 24%).

CONCLUSIONS

Health professionals need to monitor the health information carried in these publications, which reach between 1 and 2 million students per grade level each week. Although neither publication had perfect tobacco coverage, Scholastic News was significantly better than Weekly Reader.

Tobacco industry smokers' rights publications: a content analysis

OBJECTIVES

This study was undertaken to identify the content of tobacco industry smokers' rights publications and to analyze their major themes.

METHODS

Fifty-eight issues of smokers' rights publications from 1987 to 1992 were selected at random and analyzed. The number of publications per year, number of mentions (sentences) in different thematic categories per year, and number of mentions per category per publication were examined.

RESULTS

The number of smokers' rights publications increased rapidly from 1987 to 1992. The number of mentions across all thematic categories increased over time, with the largest numbers appearing in 1990, 1991, and 1992. The category of Political and Social Action comprised the highest average number of mentions across years.

CONCLUSIONS

These publications appear to be consistent with past and present tobacco industry strategies to counter tobacco control efforts and negative public perceptions by attempting to refute scientific evidence about the health impact of environmental tobacco smoke. Additionally, they serve the industry goals of encouraging smokers to take action to protect their rights, mobilizing public opinion, and delaying societal rejection of smoking and secondhand smoke and acceptance of smoking restrictions.

Environmental tobacco smoke. The Brown and Williamson documents

OBJECTIVE

To examine the tobacco industry's public and private responses to rising concern over the health effects of environmental tobacco smoke (ETS).

DATA SOURCES

Documents from Brown and Williamson Tobacco Corporation (B&W), the British American Tobacco Company (BAT), and other tobacco interests provided by an anonymous source, obtained from Congress, and received from the private papers of a former BAT officer.

STUDY SELECTION

All available materials, including confidential reports regarding research and internal memoranda exchanged between tobacco industry lawyers.

CONCLUSIONS

Privately, B&W and BAT began conducting research related to ETS in the mid 1970s. BAT researchers appear to have determined that sidestream smoke produces irritation, that it contains toxic substances including N-nitrosamines, and that it is "biologically active" (eg, carcinogenic) in laboratory tests. During the 1980s, the primary purpose of BAT's research related to ETS was to develop a new cigarette that emitted less irritating and less biologically active sidestream smoke. Publicly, the tobacco industry has denied that exposure to ETS has been proven dangerous to health. It has criticized the methodology of published research on ETS, even when some of its own consultants have privately acknowledged that the research was valid. In addition, the industry has funded scientific research with the stated purpose of anticipating and refuting the evidence against ETS. The tobacco industry's strategy regarding passive smoking has been remarkably similar to its strategy regarding active smoking. It has privately conducted internal research, at least some of which has supported the conclusion that passive smoking is dangerous to health, while it has publicly denied that the hazards have been proven.

Looking through a keyhole at the tobacco industry. The Brown and Williamson documents

OBJECTIVE

To introduce a series of papers discussing previously undocumented tobacco industry activities regarding strategies to avoid products liability litigation, understand nicotine addiction, and manipulate both internal and external scientific research on the effects of both active and passive smoking.

DATA SOURCES

Documents from Brown and Williamson Tobacco Corporation (B&W), the British American Tobacco Company (BAT), and other tobacco interests provided by an anonymous source, obtained from Congress, and received from the private papers of a former BAT officer.

STUDY SELECTION

All available materials, including confidential reports regarding research and internal memoranda exchanged between tobacco industry lawyers.

CONCLUSIONS

These documents provide our first look at the inner workings of the tobacco industry during the crucial period in which the scientific case that smoking is addictive and kills smokers solidified. The documents show a sophisticated legal and public relations strategy to avoid liability for the diseases induced by tobacco use. The documents show that lawyers steered scientists away from particular research avenues, which is inconsistent with the company's purported disbelief in the causation and addiction claims; if the company had been genuinely unconvinced by the causation and addiction hypotheses, then it should have had no concern that new research would provide ammunition for the enemy. Quite the contrary, the documents show that B&W and BAT recognized more than 30 years ago that nicotine is addictive and that tobacco smoke is "biologically active" (eg, carcinogenic).

Nicotine and addiction. The Brown and Williamson documents

OBJECTIVE

To learn how nicotine has been regarded by a major tobacco company.

DATA SOURCES

Documents from Brown and Williamson Tobacco Corporation (B&W), the British American Tobacco Company (BAT), and other tobacco interests provided by an anonymous source, obtained from Congress, and received from the private papers of a former BAT officer.

STUDY SELECTION

All available materials, including confidential reports regarding research and internal memoranda exchanged between tobacco industry lawyers.

CONCLUSIONS

During a period of 22 years (1962 to 1984), employees of B&W and BAT conducted research and commented on the pharmacology of nicotine. They consistently regarded nicotine as the pharmacological agent that explained tobacco use. In the early part of the period under study, officials of the companies wrote about nicotine addiction explicitly. Inhalation of cigarette smoke by the consumer was recognized throughout the period as necessary for the normal function of a cigarette. The documents contain little indication that research was conducted on either the taste or the flavor of nicotine. The documents reveal an intention on the part of B&W and its corporate parent to affect the function of the body with nicotine.

Lawyer control of the tobacco industry's external research program. The Brown and Williamson documents

OBJECTIVE

To examine the involvement of tobacco industry lawyers in the selection of tobacco industry scientific research projects and to examine how the research was used to influence public policy.

DATA SOURCES

Documents from Brown and Williamson Tobacco Corporation, the British American Tobacco Company (BAT), and other tobacco interests provided by an anonymous source, obtained from Congress, and received from the private papers of a former BAT officer.

STUDY SELECTION

All available materials, including confidential reports regarding research and internal memoranda exchanged between tobacco industry lawyers.

CONCLUSIONS

The involvement of tobacco industry lawyers in the selection of scientific projects to be funded is in sharp contrast to the industry's public statements about its review process for its external research program. Scientific merit played little role in the selection of external research projects. The results of the projects were used to generate good publicity for the industry, to deflect attention away from tobacco use as a health danger, and to attempt, sometimes surreptitiously, to influence policymakers.