A description of cigarette smoking cessation and resumption in the Framingham Study

The effect of alcohol use on smoking cessation: A systematic review

Only a small minority of all attempts to stop smoking are successful, especially among smokers who are heavy drinkers and those with an alcohol use disorder. The current systematic review focuses on the negative effects of alcohol use, either before or during attempts to quit smoking, on the success rate of these attempt(s) in alcohol-drinking tobacco smokers. We conducted a systematic review of naturalistic and experimental studies, which included at least 40 tobacco smokers with a recorded drinking status (non-drinking, heavy drinking, alcohol use disorder) and a clearly documented change in alcohol consumption. We could not conduct a meta-analysis and, thus, used consistency across studies to draw conclusions. The evidence presented here shows that alcohol use is associated with lower rates of success in quitting smoking in 20 out of 27 studies. This includes both lapses and relapses. Similarly, in 19 out of 20 long-term follow-up studies, the duration of smoking abstinence was shorter among persons with higher alcohol consumption. Finally, 12 out of 13 experimental studies showed that exposure of smokers to alcohol cues or to drinking of alcohol induce a strong propensity to smoke. It is, therefore, recommended for smokers who drink alcohol and who intend to quit smoking to use an integrated approach, i.e., to stop or substantially reduce their alcohol consumption before and/or during their attempt to quit smoking.

The association of smoking cessation with mortality from pneumonia among middle-aged and elderly community residents: The Japan Collaborative Cohort (JACC) study

Several studies have shown that smoking is a significant risk factor for pneumonia, but it is uncertain to what extent smoking cessation reduces the risk. This study aimed to investigate whether and to what extent smoking cessation is associated with reduced risk of mortality from pneumonia in a Japanese, prospective, community-based cohort. We examined 94,972 individuals (mean age, 57 years; women, 57%) who provided valid responses to a lifestyle questionnaire including questions about smoking. We used years of smoking cessation at baseline to divide former smokers into 5 groups: 0-1 year, 2-4 years, 5-9 years, 10-14 years, and 15 years or more. The endpoint was the underlying cause of death from pneumonia. During the median 19-year follow-up of 94,972 study participants, 1806 died from pneumonia. Multivariable hazard ratios (95% confidence intervals) compared with the current smokers were 1.02 (0.72-1.45) for 0-1 year of smoking cessation at baseline, 0.92 (0.70-1.22) for 2-4 years, 0.95 (0.74-1.21) for 5-9 years, 0.71 (0.53-0.96) for 10-14 years, 0.63 (0.48-0.83) for 15 years or more, and 0.50 (0.36-0.70) for never-smokers. Although smoking increases the risk of pneumonia mortality, the present study showed that the risk of pneumonia mortality decreased with years of smoking cessation, eventually improving to levels similar to those of non-smokers for 10 years or more. Continued smoking cessation may be effective in preventing pneumonia deaths.

Smoking and caffeine consumption: a genetic analysis of their association

Smoking and caffeine consumption show a strong positive correlation, but the mechanism underlying this association is unclear. Explanations include shared genetic/environmental factors or causal effects. This study employed three methods to investigate the association between smoking and caffeine. First, bivariate genetic models were applied to data of 10 368 twins from the Netherlands Twin Register in order to estimate genetic and environmental correlations between smoking and caffeine use. Second, from the summary statistics of meta-analyses of genome-wide association studies on smoking and caffeine, the genetic correlation was calculated by LD-score regression. Third, causal effects were tested using Mendelian randomization analysis in 6605 Netherlands Twin Register participants and 5714 women from the Avon Longitudinal Study of Parents and Children. Through twin modelling, a genetic correlation of r0.47 and an environmental correlation of r0.30 were estimated between current smoking (yes/no) and coffee use (high/low). Between current smoking and total caffeine use, this was r0.44 and r0.00, respectively. LD-score regression also indicated sizeable genetic correlations between smoking and coffee use (r0.44 between smoking heaviness and cups of coffee per day, r0.28 between smoking initiation and coffee use and r0.25 between smoking persistence and coffee use). Consistent with the relatively high genetic correlations and lower environmental correlations, Mendelian randomization provided no evidence for causal effects of smoking on caffeine or vice versa. Genetic factors thus explain most of the association between smoking and caffeine consumption. These findings suggest that quitting smoking may be more difficult for heavy caffeine consumers, given their genetic susceptibility.

Acute effects of low and high dose alcohol on smoking lapse behavior in a laboratory analogue task

RATIONALE

Smoking lapses (i.e., returns to smoking after quitting) often occur following alcohol consumption with observational data suggesting greater quantities of alcohol lead to greater risk. However, a causal dose-dependent effect of alcohol consumption on smoking lapse behavior has not been established, and the mechanisms that might account for such an effect have not been tested.

OBJECTIVES

In a within-subjects design, we examined the effects of low- (0.4 g/kg) and high-dose (0.8 g/kg) alcohol, relative to placebo, on smokers' ability to resist initiating smoking after acute smoking abstinence.

METHODS

Participants were 100 heavy alcohol drinkers, smoking 10-30 cigarettes per day. Across three separate days, participants consumed placebo, low-dose, or high-dose alcohol following 3 h of smoking abstinence and, 35 min later, were offered the opportunity to smoke while resisting smoking was monetarily reinforced proportional to the amount of time delayed.

RESULTS

Consistent with a dose-response effect, participants smoked 3.35 min (95 % confidence intervals (CI) [-7.09, 0.40], p = .08) earlier following low-dose alcohol and 6.36 min (95 % CI [-9.99, -2.73], p = .0006) earlier following high-dose alcohol compared to drinking a placebo beverage. Effects of dose on smoking behavior were partially mediated by increases in urge to smoke. There was no evidence that alcohol's effects on urge to smoke or ability to resist smoking were mediated through its stimulating or sedating effects.

CONCLUSIONS

Alcohol can reduce the ability to resist smoking in a dose-dependent fashion, in part, due to its effect on increasing the intensity of smoking urges.

Relations of alcohol consumption with smoking cessation milestones and tobacco dependence

OBJECTIVE

Alcohol consumption is associated with smoking cessation failure in both community and clinical research. However, little is known about the relation between alcohol consumption and smoking cessation milestones (i.e., achieving initial abstinence, avoiding lapses and relapse). Our objective in this research was to examine the relations between pretreatment alcohol consumption patterns (non/infrequent drinker, moderate drinker, binge drinker) and smoking cessation milestones and tobacco dependence.

METHOD

Data were collected from 1,504 smokers (58.2% women; 83.9% White; mean age = 44.67 years, SD = 11.08) making an aided smoking cessation attempt as part of a clinical trial. Alcohol consumption pattern was determined with the Composite International Diagnostic Interview. Tobacco dependence was assessed with the Wisconsin Inventory of Smoking Dependence Motives (WISDM).

RESULTS

Alcohol consumption pattern was significantly associated with initial cessation and lapse, and these findings remained after controlling for the effects of treatment, race, gender, and cigarettes per day. Relative to moderate drinkers, both non/infrequent drinkers and binge drinkers were less likely to achieve initial cessation (p < .05), and binge drinkers were more likely to lapse (p < .01). When drinking categories were compared on tobacco dependence indices, results showed that relative to moderate drinkers, non/infrequent drinkers scored higher on several WISDM Primary Dependence Motives subscales (Tolerance, Loss of Control, and Automaticity) and binge drinkers scored higher on WISDM Secondary Dependence Motives subscales (Cue Exposure and Social-Environmental Goads).

CONCLUSIONS

Non/infrequent drinkers' smoking cessation difficulties may be particularly related to core features of tobacco dependence, whereas binge drinkers' difficulties may be related to environmental and social influences.

Social influences on smoking in middle-aged and older women

The purpose of this study was to examine the role of 2 types of social influence--general social support and living with a smoker--on smoking behavior among middle-aged and older women in the Women's Health Initiative (WHI) Observational Study. Participants were postmenopausal women who reported smoking at some time in their lives (N=37,027), who were an average age of 63.3 years at baseline. Analyses used multiple logistic regression and controlled for age, educational level, and ethnicity. In cross-sectional analyses, social support was associated with a lower likelihood and living with a smoker was associated with a higher likelihood of being a current smoker and, among smokers, of being a heavier smoker. Moreover, in prospective analyses among baseline smokers, social support predicted a higher likelihood and living with a smoker predicted a lower likelihood of smoking cessation 1-year later. Further, in prospective analyses among former smokers who were not smoking at baseline, social support predicted a lower likelihood and living with a smoker predicted a higher likelihood of smoking relapse 1-year later. Overall, the present results indicate that social influences are important correlates of smoking status, smoking level, smoking cessation, and smoking relapse among middle-aged and older women.

Sex differences in stimulus expectancy and pharmacologic effects of a moderate dose of alcohol on smoking lapse risk in a laboratory analogue study

RATIONALE

Alcohol use is often implicated in initial lapses to smoking during quit smoking attempts. Mechanisms explaining this association are unknown but could include (a) learned associations between drinking and smoking or (b) direct pharmacologic effects of alcohol.

OBJECTIVES

In a 2 (told alcohol vs. told placebo) × 2 (0.4 g/kg vs. 0.0 g/kg ethanol) between-subjects balanced placebo design, we examined instruction and beverage condition effects on smokers' ability to resist initiating smoking and whether these effects differed by sex.

METHODS

Participants were 96 heavy alcohol drinkers, smoking 10-30 cigarettes per day. After 15 h of smoking abstinence, participants consumed either an alcoholic or a nonalcoholic beverage and 35 min later completed a smoking lapse task.

RESULTS

Overall, neither instructions nor beverage contents influenced behavior on the smoking lapse task. However, the instruction condition had different effects in men and women. Women, but not men, were more likely to smoke and reported expecting greater satisfaction from smoking when they were told alcohol compared to told placebo. The effects of instruction condition on smoking behavior were not mediated by self-reported expected satisfaction from smoking.

CONCLUSIONS

Women may be more likely to choose to smoke after drinking moderate amounts of alcohol because of their expectations rather than the pharmacological effects of the alcohol.

Depressive symptoms and smoking in middle-aged and older women

INTRODUCTION

Smoking research and intervention efforts have neglected older women. Depressive symptoms, which are common in middle-aged and older women, are related to the maintenance of adult smoking.

METHODS

This study investigated the relation of a composite measure of current depressive symptoms, derived from a short form of the Center for Epidemiological Studies Depression Scale, and history of depressive symptoms, derived from two items from the Diagnostic Interview Schedule, to smoking outcomes in the Women's Health Initiative Observational Study (N = 90,627). Participants were postmenopausal with an average age of 63.6 years at baseline. Participants were recruited from urban, suburban, and rural areas surrounding 40 clinical centers in the United States. Analyses controlled for age, educational level, and ethnicity.

RESULTS

In multinomial logistic regression analyses, depressive symptoms were related cross-sectionally to current light (odds ratio [OR] = 1.19, 95% CI = 1.14-1.23) and heavier (OR = 1.28, 95% CI = 1.23-1.32) smoking at baseline compared with nonsmokers. In prospective multiple logistic regression analyses, baseline depressive symptoms were negatively predictive of smoking cessation at a 1-year follow-up (OR = .85, 95% CI = 0.77-0.93) and at participants' final assessments in the study (OR = .92, 95% CI = 0.85-0.98). Light smokers had more than 2 times higher odds of smoking cessation than did heavier smokers.

CONCLUSIONS

The present findings demonstrate a consistent link between depressive symptoms and negative smoking-related behaviors among middle-aged and older women at both light and heavier smoking levels.

Quitting smoking and change in alcohol consumption in the International Tobacco Control (ITC) Four Country Survey

Although frequent heavy drinking has been associated with decreased odds of quitting smoking, the extent to which smoking cessation is associated with decreased alcohol consumption is less clear. The present study examined over a 2-year period whether individuals who quit smoking for at least 6 months, compared to those making a quit attempt but continuing to smoke and to those not making any attempt to quit smoking, showed greater reductions in drinking frequency, average weekly quantity of alcohol consumption, and frequency of heavy drinking. Data were drawn from the International Tobacco Control Four Country Survey, a prospective cohort study of smokers in Australia, Canada, the UK, and the US. A total of 3614 participants provided alcohol data at one study wave and were re-interviewed 2 years later regarding smoking and alcohol use. Consistent with prior studies, individuals who drank heavily (4+/5+ drinks for women and men, respectively) more than once a week had especially low rates of quitting smoking. There was little evidence, however, that those who achieved sustained smoking cessation made greater reductions in drinking compared to those who continued to smoke. These results were consistent across countries and sexes and did not differ significantly by heaviness of smoking. Results indicate that quitting smoking, in and of itself, does not lead to meaningful changes in alcohol use. Therefore, interventions and policies directed towards increasing smoking cessation are unlikely to affect rates of hazardous drinking unless they include specific elements that address alcohol consumption.

Alcohol use and initial smoking lapses among heavy drinkers in smoking cessation treatment

INTRODUCTION

This study examined alcohol use and its association with initial smoking lapses among heavy nondependent drinkers in smoking cessation treatment.

METHODS

Participants were 236 heavy drinking smokers in a randomized clinical trial testing the efficacy of incorporating brief alcohol intervention into smoking cessation treatment.

RESULTS

Of the 178 participants who reported a smoking lapse, 41.5% lapsed when drinking alcohol. Those who had alcohol-involved lapses had significantly lower tobacco dependence severity and drank more drinks per week than those who had non-alcohol-involved lapses. The majority of alcohol-involved lapses were in a bar/restaurant, with other people, and when they were in a happy/good mood. In survival analyses with alcohol consumption as a time-varying covariate, moderate drinking days were associated with almost four times greater risk of smoking lapse than non-drinking days, and heavy drinking doubled the risk of lapsing compared with moderate drinking.

DISCUSSION

Results suggest that alcohol-related lapses are qualitatively different from lapses that do not involve alcohol. Furthermore, among heavy drinkers in cessation treatment, even moderate alcohol use is associated with increased risk of smoking, with heavy drinking further increasing the risk. Smoking cessation treatments for heavy alcohol drinkers should highlight the lapse risk associated with any alcohol consumption and with heavy drinking during a quit smoking attempt.

Low-to-moderate alcohol consumption and smoking cessation rates: retrospective analysis of 4576 elderly ever-smokers

BACKGROUND

Smoking and alcohol consumption are two major risk factors for manifold morbidity and mortality outcomes and are highly correlated with each other. No conclusion has been reached concerning whether cigarette smokers drinking alcohol have more difficulties with smoking cessation. We aimed to elucidate the association of concurrent alcohol consumption with the probability of smoking cessation in non-clinical populations.

METHODS

Retrospective analysis in 4576 ever-smoking participants of the baseline survey of ESTHER, a population-based study in Germany, aged 50-74 at enrollment in general practitioner offices. Life-course histories of alcohol consumption were obtained from questionnaire items covering exposure intensities at ages 20, 30, 40, 50 and at the time of enrollment. Extended Cox regression modelling allowing for the time-varying nature of alcohol consumption was employed to model the time from smoking initiation to smoking cessation.

RESULTS

Using alcohol abstainers as the reference group and controlling for potential confounders, relative cessation rates (95% CI) increased to 1.17 (1.02, 1.34), 1.36 (1.20, 1.55), 1.45 (1.27, 1.66) and 1.32 (1.13, 1.53) with concurrent consumption of 1-39, 40-99, 100-199 and 200+g alcohol/week. This pattern persisted in extensive sensitivity analyses.

CONCLUSIONS

The results of these analyses of time-varying concurrent alcohol consumption and smoking suggest that drinking low-to-moderate amounts of alcohol as common in the general population might actually facilitate cessation in non-clinical settings.

Alcohol consumption and quitting smoking in the International Tobacco Control (ITC) Four Country Survey

Although greater alcohol consumption has been associated with decreased odds of quitting smoking in prospective studies, the aspects of drinking most strongly associated with quitting have not been fully explored and examination of potential confounder variables has been limited. Further studies are needed to inform efforts to enhance smoking cessation among the substantial portion of smokers who drink alcohol. The present study examines: (a) drinking frequency, average weekly quantity of alcohol consumption, and frequency of heavy drinking as prospective predictors of quit smoking behaviors, (b) difference across countries in this prediction, and (c) third variables that might account for the association between alcohol consumption and quitting smoking. Data were drawn from the International Tobacco Control Four Country Survey, a prospective cohort study of smokers in Australia, Canada, the UK, and the US. A total of 4831 participants provided alcohol data at one study wave and were re-interviewed 1 year later. Individuals who drank heavily (4+/5+ drinks for women and men, respectively) more than once a week had significantly lower rates of quitting smoking than all other participants, in part due to the fact that a significantly lower proportion of those making a quit attempt remained quit for more than 1 month at follow-up. The role of frequent heavy drinking did not differ by country or sex and was not accounted for by demographics, smoking dependence, or attitudes regarding quitting smoking. Neither drinking frequency nor weekly quantity of consumption showed robust associations with quitting behaviors. Results indicate further study of interventions to address heavy drinking among smokers is warranted.

Addressing heavy drinking in smoking cessation treatment: a randomized clinical trial

Heavy alcohol use frequently co-occurs with cigarette smoking and may impede smoking cessation. This clinical trial examined whether smoking cessation treatment that incorporates brief alcohol intervention can improve smoking cessation outcomes (7-day verified point prevalence abstinence) and reduce drinks consumed per week. Heavy drinkers seeking smoking cessation treatment were assigned by urn randomization to receive, along with 8 weeks of nicotine replacement therapy, either a 4-session standard smoking cessation treatment (ST, n = 119) or standard treatment of equal intensity that incorporated brief alcohol intervention (ST-BI, n = 117). Across follow-ups over 26 weeks, participants in ST-BI reported approximately 20% fewer drinks per week (p < .027) and greater smoking abstinence (adjusted odds ratio = 1.56; 95% confidence interval = 1.01, 2.43) than did those in ST; however, effects on smoking were primarily evident at 2 weeks after quit date and were essentially absent by 16 weeks. The effect of ST-BI on smoking outcome was most robust among moderately heavy drinkers compared with that on very heavy drinkers. Integrating brief alcohol intervention into smoking cessation treatment appears feasible, but further development is needed to yield lasting effects on smoking.

Cigarette smoking and the lifetime alcohol involvement continuum

Greater understanding of how alcohol use relates to the initiation, progression, and persistence of cigarette smoking is of great significance for efforts to prevent and treat smoking and excessive drinking and their substantial combined iatrogenic effects on health. Studies investigating the relationship between levels of alcohol involvement and smoking have typically been limited by analytic approaches that treat drinking behavior and alcohol use disorder diagnoses as separate phenomena rather than as indicators of a single latent alcohol involvement dimension. The purposes of the present study were (a) to create a lifetime index of alcohol involvement that integrates information about alcohol consumption and alcohol problems into a single measure and (b) to relate this index to initiation of smoking, progression from initiation to daily smoking, progression from initiation to dependence, and persistence of smoking. Rasch model analyses of data from 1508 middle-aged (34-44 years) adults showed that creating an additive index of lifetime alcohol involvement was psychometrically supported. Significant quadratic effects of alcohol involvement on initiation, progression, and persistence of smoking demonstrated that there were specific regions of the alcohol involvement continuum that were particularly strongly related to increased smoking. These results provide the most comprehensive depiction to date of the nature of the relationship between lifetime alcohol involvement and lifetime cigarette smoking and suggest potential avenues for research on the etiology and maintenance of smoking and tobacco dependence.

Compliance with risk factor modification: early-onset versus late-onset stroke patients

OBJECTIVES

To study the compliance to risk factor modifications and factors related to it, which may be different between early-onset (15-45 years) and late-onset (>45 years) stroke patients. These issues have not yet been addressed properly.

METHODS

We selected 170 early-onset and 340 late-onset stroke patients from the Asan Stroke Registry. The patients were then followed for 1-5 years (an average of 3.4 years) after the onset of stroke. We used a standardized questionnaire to assess the level of compliance and examine the factors contributing to noncompliance.

RESULTS

Ninety-six early-onset and 160 late-onset patients completed a standardized questionnaire. Early-onset patients were less compliant than late-onset patients in the use of antihypertensive medication (p < 0.01), the cessation of cigarette smoking (p < 0.05) and in regular exercise (p < 0.05). Multivariate analysis showed that factors related to noncompliance in early-onset stroke patients included 'a lack of insurance' (noncompliance with the use of antihypertensive medication) and male gender (noncompliance with participation in regular exercise). Factors related to noncompliance in late-onset stroke patients included a high number of cigarettes consumed before the stroke (noncompliance with the cessation of smoking), the lack of regular exercise and a severe modified Rankin scale (noncompliance with regular exercise).

CONCLUSION

Early-onset stroke patients are generally less compliant than late-onset stroke patients and the factors related to noncompliance in these groups are different. Therefore, strategies should be developed for improving patient compliance, based on these differences.

Genetic analysis of maximum cigarette-use phenotypes

Background

Using the Framingham Heart Study data set provided for Genetic Analysis Workshop 13, we defined the cigarette-use phenotype M for smokers to be the maximum number of cigarettes-per-day (MAXCIG) reported over the longitudinal course of the study. Adjustments were made for the significant covariates of gender and year of birth, and sib-pair based linkage analysis was performed.

Results

The primary analyses, in which individuals with MAXCIG = 0 were considered to have missing phenotype, resulted in modest linkage evidence, with LOD scores over 1 on chromosomes 5, 9, 13, 14, and 22.

Conclusions

While the results reported here do not indicate definitive evidence for linkage to specific chromosomal regions, future studies may find it useful to include direct assessments of maximum and quantitative cigarette use. In defining and analyzing quantitative or "maximum use" phenotypes, the choice of how to handle individuals with MAXCIG = 0, or alternatively, individuals who are substance-naive, is a crucial one for genetic studies of nicotine and other substance use. In this study, the linkage results vary greatly depending on whether or not these "unexposed" individuals are included in the analyses.

Evolving patterns of tobacco use in northern Sweden

BACKGROUND AND OBJECTIVES

Cross-sectional data from northern Sweden suggest that the increased use of Swedish moist snuff (snus) may have contributed to a decline in the prevalence of smoking, especially amongst men. This study describes the evolving patterns of tobacco use in this population over the period 1986-1999.

DESIGN

This is a prospective follow-up study of 1651 men and 1756 women, aged 25-64 years, who were enrolled in the northern Sweden MONICA project (entry in 1986, 1990, 1994) and who were followed-up in 1999. Information on tobacco use at entry and at follow-up was used to describe the stability of tobacco use over a period of 5-13 years ending in 1999.

RESULTS

Snus was the most stable form of tobacco use amongst men (75%); only 2% of users switched to cigarettes and 20% quit tobacco altogether. Smoking was less stable (54%); 27% of smokers were tobacco-free and 12% used snus at follow-up. Combined use (smoking and snus) was the least stable (39%), as 43% switched to snus and 6% switched to cigarettes. Former users of both products were much less stable than former users of either cigarettes or snus. The stability of smoking amongst women was 69%, which was higher than that amongst men (P < 0.05).

CONCLUSIONS

The use of snus played a major role in the decline of smoking rates amongst men in northern Sweden. The evolution from smoking to snus use occurred in the absence of a specific public health policy encouraging such a transition and probably resulted from historical and societal influences.

Eight-year follow-up of a community-based large group behavioral smoking cessation intervention

OBJECTIVE

To evaluate the effectiveness of a large group community-based behavioral smoking cessation intervention over an 8-year follow-up period and to determine precessation predictors of cessation at each follow-up time.

RESEARCH APPROACH

Behavioral intervention followed by three longitudinal follow-up interviews.

SETTING

Regional Outpatient Cancer Centre.

STUDY PARTICIPANTS

971 participants in smoking cessation clinics held between 1986 and 1990.

INTERVENTION

Eight 90-minute sessions over 4 months utilizing education, self-monitoring, nicotine fading, a group quit date and behavioral modification techniques. Up to 110 smokers participated in each group program.

MAIN OUTCOME MEASURES

Cessation rates at 3, 6, and 12 months postquit and at 8-year follow-up. Differences between successful and unsuccessful participants in precessation demographic, smoking history, and smoking behavior variables.

RESULTS

At 3 months postquit date, 39.3% of the 971 participants reported that they were not smoking, decreasing to 32.1% at 6 months and 26.0% at 12 months. At the 8-year follow-up, 33.9% of the original sample were contacted, and of those, 47.7% reported that they were currently not smoking. There were nine predictors of cessation at the end of the program (3 months), which were similar to those previously reported in the literature. Similarly, at 6 and 12 months, six factors were associated with not smoking. At the 9-year follow-up the only variable predictive of continued abstinence was being female (p < .05).

CONCLUSIONS

This program was successful in promoting smoking cessation and maintenance, even with its large-group format. Predictive factors were similar to those previously reported in the literature.

Babesia canis canis, Babesia canis vogeli, Babesia canis rossi: differentiation of the three subspecies by a restriction fragment length polymorphism analysis on amplified small subunit ribosomal RNA genes

The parasites Babesia canis and Babesia gibsoni (phylum Apicomplexa) are responsible for canine babesiosis throughout the world. Babesia canis was previously described as a group of three biologically different subspecies, namely B. canis canis, B. canis vogeli, and B. canis rossi. We report partial sequences of small subunit ribosomal RNA gene (ssu-rDNA) of each subspecies amplified in vitro with primers derived from a semi-conserved region of the ssu-rDNA genes in other Babesia species. The polymerase chain reaction combined with a restriction fragment length polymorphism analysis, using HinfI and TaqI restriction enzymes, confirmed the separation of B. canis into three subspecies. These sequences were compared with previously published sequences of other Babesia species. A phylogenetic approach showed that the three subspecies of B. canis belong to the clade of Babesia species sensu stricto where B. canis canis clusters with B. canis rossi whereas B. canis vogeli might form a monophyletic group with the cluster B. divergens and B. odocoilei. Our results show that the three subspecies of B. canis can readily be differentiated at the molecular level and suggest that they might be considered as true species.

Predictors of smoking cessation following physicians' counseling

BACKGROUND

The purpose of this study was, to identify predictors of quitting following general practitioners' (GP) anti-smoking counseling.

METHODS

We studied determinants (characterized following the Precede framework) of successful quitting (1 year sustained abstinence, biochemically confirmed at 6- and 12-month follow-up) among 861 smokers randomized to the intervention groups based on repeated counseling (RC), RC + spirometric testing, and RC + nicotine gum, in a smoking cessation trial carried out in Turin, Italy.

RESULTS

GPs' intervention worked best for male (OR = 2.30; 95% CI, 1.13-4.52) and married (OR = 3.63; 95% CI, 1.37-9.59) smokers, for smokers who had maintained abstinence for at least 1 month in the past (OR = 6.78; 95% CI, 1.56-29.52) or at their first quit attempt (OR = 10.91; 95% CI, 2.37-50.13), and for those who spontaneously reduced their coffee consumption (OR = 3.30; 95% CI, 1.59-6.82); heavy smokers (> = 20 cig/day OR = 0.48; 95% CI, 0.24-0.93) and those living with other smokers (> = 1 smokers in the household: OR = 0.44; 95% CI, 0.22-0.90) were less likely to give up. Previous antismoking advice by the GP represented a strong barrier to success for healthy smokers (OR = 0.19; 95% CI, 0.07-0.52), but not for those reporting symptoms of shortness of breath (OR = 0.63; 95% CI, 0.39-9.20). There were no interactions between predictors and treatment conditions.

CONCLUSIONS

Assessment of factors influencing quitting would allow GPs to tailor their message to address existing barriers and to help patients utilize their resources for change.

Is the intention to quit smoking influenced by other heart-healthy lifestyle habits in 30- to 60-year-old men?

The aim of this study was to analyze whether the intention to quit smoking was associated with other lifestyle habits healthy for the heart, namely a low-fat diet and regular exercise, using variables suggested by the theory of planned behavior. Self-administered postal questionnaires were sent to 3,200 men 30 to 60 years of age residing in Laval, Quebec. With a response rate of 70.9%, 671 respondents (29.6%) were smokers. A significant proportion (43%) had all three risk behaviors--smoking, a high-fat diet, and sedentariness, and 42% had two--smoking and one of the other behaviors. The remaining had a single risk behavior, namely smoking. Regression analysis suggested that a healthy diet and exercise had no significant influence on the intention to quit smoking. However, men who had a stronger intention to quit smoking than others had a more favorable attitude toward the behavior, a stronger perception of approval in achieving it on the part of important referents, stronger perceived behavioral control, and were among those who smoked fewer cigarettes per day, but had made more attempts to quit. These results can assist in designing better heart-health intervention programs for this high-risk population.

Smoking habits of future physicians: a survey among medical students of a south German university

Physicians can play a key role in promoting abstinence from tobacco. In many European countries, however, a large proportion of physicians are still smoking themselves. To assess smoking habits of future physicians, a cross-sectional study was conducted in 1992/1993 among 817 students enrolled in the first, third, and fifth years of medical school at the university of Ulm, Germany, using a self-administered questionnaire. The overall participation rate was 85.2%. Prevalence of current smoking was 17.6% among female participants and 29.2% among male participants. Among male students, smoking prevalence varied between 22.9% in the first year and 34.6% in the fifth year of medical school. Among female students, there were only minor differences in smoking prevalence between the first, third and fifth years at medical school. Most of the smokers had started to smoke prior to entry into medical school. Among third and fifth year students, slightly more students quit smoking than started to smoke during medical school, and smokers in the fifth year of medical school were more frequently willing to quit than smokers in the first and third year. Factors associated with regular smoking of medical students, after adjustment for potential confounders in multivariable analysis, were age, sex, and maternal smoking. While smoking prevalence was somewhat lower in the present study than in previous studies from Germany, further efforts are needed to reduce smoking among future physicians in this country.

Behavioral diagnosis of 30 to 60 year-old men in the Fabreville Heart Health Program

To develop effective interventions in the Fabreville Heart Health Program, a behavioral diagnosis was conducted on a sample of 1,600 men 30 to 60 years of age residing in the Fabreville district of Laval, Quebec's second most populous city. The response rate of the self-administered postal questionnaire was 73.5%. The results indicate that dietary fat consumption, smoking and a sedentary lifestyle were more prevalent among the younger respondents, particularly those less-educated. The results underline the importance of segmenting the target population so that heart health interventions can respond to the specific needs of each sub-population. Furthermore, the data seem to suggest the need to adapt educational messages to the target lifestyle habits. The results showed that in terms of diet, consumption of meat and dairy products contributed the most to fat intake. Of the 30% who were smokers, a large proportion would be reluctant to stop the habit; 20% smoked 26 cigarettes or more a day, and more than half had already tried once or more to stop. Although 60% of respondents indicated they engaged in physical activity, only 37.0% did it regularly. These results demonstrate the need to clearly target specific behaviours and subgroups in our promotion messages for a healthy heart.

What determines mortality risk in male former cigarette smokers?

OBJECTIVES

The purpose of this study was to examine what factors determine the mortality experience of male ex-cigarette smokers, those who no longer smoke at all and those who changed to pipe or cigar smoking.

METHODS

A cohort study was undertaken with 18-year mortality data on 19,018 men.

RESULTS

Ex-cigarette smokers had an intermediate mortality risk compared with never and current smokers. Ex-cigarette smokers who switched to pipe smoking had higher mortality than those who no longer smoked at all. The mortality rates for pipe and cigar smokers who were former cigarette smokers were higher than those for pipe or cigar smokers who had never smoked cigarettes. Ex-cigarette smokers who consumed more than 20 cigarettes per day for more than 20 years experienced increased mortality for both coronary heart disease and neoplasms, even after 30 years of cessation.

CONCLUSIONS

These results support the notion that an elevated mortality risk may be seen for ex-cigarette smokers, even after they have given up smoking for many years. Ex-cigarette smokers who change to a pipe have a greater mortality risk than those who no longer smoke at all.

A longitudinal analysis of predictors of quitting smoking among participants in a self-help intervention trial

Predictors of 7-day abstinence from smoking were identified among participants in a randomized self-help smoking-cessation intervention trial conducted from 1985 to 1988 in Seattle, WA. Subjects were adult smokers belonging to a health maintenance organization who responded to an offer of free quitting assistance. Self-reported smoking status was assessed at 8, 16, and 24 months following enrollment. Predictors of abstinence were identified by longitudinal data analysis using Generalized Estimating Equations (GEEs), a modeling approach which handles repeated-measures data and accommodates time-dependent as well as time-independent covariates. Seventeen items emerged as significant (p < .05) predictors, with odds ratios ranging from 1.3 to 2.1. While much of the previous work in smoking-cessation research has focused on demographic and smoking history variables, results of this study indicate that emphasis should also be placed on psychosocial/motivational factors and quitting activities as important predictors of abstinence. Longitudinal data analysis represents a powerful technique for handling correlated (repeated measures) data, which may prove very useful for future studies of smoking cessation as well as other dynamic processes.

Predictors of smoking cessation and relapse in older adults

We examined longitudinal changes in smoking behavior among older adults in three community cohorts of the Established Populations for Epidemiologic Studies of the Elderly. Smoking prevalence declined from 15% at baseline to 9% during 6 years of follow-up. Annual smoking cessation and relapse rates were 10% and less than 1%, respectively. Interval diagnosis of myocardial infarction, stroke, or cancer increased subsequent smoking cessation but not relapse. Although smoking cessation around diagnosis is increased, primary prevention could yield greater benefits.