Adolescent Waterpipe Use is Associated with Greater Body Weight: The Irbid-TRY

Background: Adult waterpipe smokers are at increased risk of obesity. However, it is unclear if adolescents, who are at the epicenter of the global waterpipe epidemic, are at similar risk. Objective: Therefore, the current study examined the waterpipe smoking relationship with obesity among adolescents. Methods: A sample of 2,313 boys and girls in grades 7–10 were surveyed about waterpipe and cigarette use in Jordan. Weight, body mass index (BMI), waist circumference, waist-to-hip ratio, and waist-to-height ratio were measured. Obesity indices were assessed as a function of smoking status (never used tobacco, current waterpipe only, current cigarettes only, and current dual smoking) as well as frequency of use of each tobacco product. Results: About 51.5% of adolescents smoked waterpipe whereas 29.8% were overweight/obese. Students who smoked waterpipe weekly had twofold greater odds of being obese than never-smokers (OR = 2.14; 95% CI = 1.08–4.21). Approximately 12% of students currently smoked waterpipe but not cigarettes, 2% smoked cigarettes but not waterpipe, and 11% smoked both. Body weight and age- and gender-specific BMI were greater for waterpipe and dual users compared to never users, especially for dual vs. never users (58.6 ±.8 vs. 55.6 ±.4 and.48 ±.07 vs..29 ±.03, respectively; p <.005). Conclusions: For dual users, greater frequency of tobacco use was associated with greater weight and BMI. Waterpipe and dual use is associated with greater obesity, BMI, and body weight among Jordanian adolescents. Given the rising epidemics of both tobacco use and obesity among Middle Eastern adolescents, the clustering of these risk factors warrants public health action.     

An electronic,smart lighter to measure cigarette smoking: A pilot study to assess feasibility and initial validity

Understanding variability in smoking patterns may inform smoking cessation interventions. Retrospective reports of cigarettes smoked per day may be biased and typically do not provide temporal precision regarding when cigarettes are smoked. However, real-time, user-initiated tracking, such as logging each time a cigarette is smoked, can be burdensome over long time frames. In this study, adult, non-treatment seeking daily smokers (N = 22) used an electronic, smart lighter to light and timestamp cigarettes for 14 days. Participants reported number of cigarettes smoked per day (CPD) via a mobile device (daily diary) and retrospectively reported CPD at the end of the study using the Timeline Followback (TLFB). Self-reported lighter satisfaction and adherence varied with 68% of participants reporting that they liked using the lighter and participants reporting using the lighter for 92% of cigarettes smoked, on average. Lighter-estimated CPD did not differ from daily diary-estimated CPD, but was significantly lower than TLFB estimates. The lighter resulted in greater day-to-day variability relative to other methods and fewer rounded cigarette counts (digit bias) relative to the TLFB. The lighter appears to be feasible for capturing data on smoking patterns in daily smokers. Though false positive cigarettes are likely low, additional technologies that augment data captured from the lighter may be necessary to reduce false negatives (missed cigarettes) and alternative lighter designs may appeal more to certain smokers.     

Gender and weight concerns in adolescent smokers

The aim of this study was to examine smoking-specific weight concerns in a well-characterized sample of adolescent daily smokers and the influence of gender, age, and body mass index (BMI). Adolescent smokers (n = 103) were asked two smoking-specific weight concern questions: “How much do cigarettes help you control your weight?” and “How concerned are you about gaining weight as a result of quitting?” A significant positive relationship was found between average daily cigarette use and belief in smoking as a means to control weight and a significant negative relationship between the years of smoking and belief that smoking controls weight. There was no significant relationship between BMI and smoking to control weight for females, whereas for males, there was a positive relationship, indicating that heavier males were more likely to report smoking to control weight. Additionally, females who smoked more cigarettes reported more concern about gaining weight upon quitting, a pattern not seen in males. Results highlight potentially important gender differences in the relationship between weight concerns and smoking and the influence these concerns may have on quitting smoking.     

Neurocognitive consequences of cigarette smoking in young adults--a comparison with pre-drug performance

The present study examined effects of current and past regular cigarette smoking in young adult subjects. One hundred and twelve 17-21-year-old subjects, assessed since infancy, were evaluated using a battery of neurocognitive tests for which commensurate measures were obtained at 9-12 years of age, prior to the initiation of regular smoking. Smokers, determined by urinalysis and self-report, were categorized as heavy (>9 cigarettes per day) and light (<9 cigarettes per day) current smokers and former smokers, the latter having smoked cigarettes regularly in the past but not for at least 6 months. A third of the subjects were currently smoking cigarettes regularly with half of these being heavy smokers. Among former smokers, the average duration of smoking was slightly less than 2 years. Overall IQ, memory, processing speed, vocabulary, attention and abstract reasoning were the primary outcomes with comparisons being made between each of the three user groups and a control group who never smoked regularly. After accounting for potentially confounding factors including clinical assessment, marihuana use and pre-drug performance in the relevant cognitive domain, current regular smokers did significantly worse than non-smokers in a variety of cognitive areas predicated upon verbal/auditory competence including receptive and expressive vocabulary, oral arithmetic, and auditory memory. This impact of current smoking appears to behave in a dose-response and duration-related fashion. In contrast, former smokers differed from the non-smokers only in the arithmetic task. These results suggest that regular smoking during early adulthood is associated with cognitive impairments in selected domains and that these deficits may be reversed upon cessation. Together, the findings add to the body of evidence to be used in persuading adolescents and young adults against the initiation of smoking and, if currently smoking, the advantages of stopping.     

Factors affecting exposure to nicotine and carbon monoxide in adult cigarette smokers

Exposure to cigarette smoke among smokers is highly variable. This variability has been attributed to differences in smoking behavior as measured by smoking topography, as well as other behavioral and subjective aspects of smoking. The objective of this study was to determine the factors affecting smoke exposure as estimated by biomarkers of exposure to nicotine and carbon monoxide (CO). In a multi-center cross-sectional study of 3585 adult smokers and 1077 adult nonsmokers, exposure to nicotine and CO was estimated by 24 h urinary excretion of nicotine and five of its metabolites and by blood carboxyhemoglobin, respectively. Number of cigarettes smoked per day (CPD) was determined from cigarette butts returned. Puffing parameters were determined through a CreSS® micro device and a 182-item adult smoker questionnaire (ASQ) was administered. The relationship between exposure and demographic factors, smoking machine measured tar yield and CPD was examined in a statistical model (Model A). Topography parameters were added to this model (Model B) which was further expanded (Model C) by adding selected questions from the ASQ identified by a data reduction process. In all the models, CPD was the most important and highest ranking factor determining daily exposure. Other statistically significant factors were number of years smoked, questions related to morning smoking, topography and tar yield categories. In conclusion, the models investigated in this analysis, explain about 30-40% of variability in exposure to nicotine and CO.     

Body mass index and regular smoking in young adult women

Little is known about the relationship between relative body weight and transition from experimentation to regular smoking in young adult women. In the current study, data from 2494 participants in wave 4 of the Missouri Adolescent Female Twin Study (aged 18–29 years) who reported ever smoking a cigarette were analyzed using logistic regression. Body mass index (BMI) at time of interview was categorized according to CDC adult guidelines, and regular smoking was defined as having ever smoked 100 or more cigarettes and having smoked at least once a week for two months in a row. Since the OR's for the overweight and obese groups did not differ significantly from one another in any model tested, these groups were combined. Forty-five percent of women who had ever smoked had become regular smokers. Testing of interactions between potential covariates and levels of the categorical BMI variable revealed a significant interaction between overweight/obesity and childhood sexual abuse (CSA; p < 0.001) associated with regular smoking. Among women reporting CSA, the association between overweight/obesity and having become a regular smoker was negative (n = 374; OR = 0.48, 95% CI: 0.28–0.81). Both underweight and overweight/obesity were positively associated with transition to regular smoking among women who did not report CSA (n = 2076; OR = 1.57, 95% CI: 1.05–2.35 and OR = 1.73, 95% CI: 1.35–2.20, respectively). These results suggest that experiencing CSA alters the association between BMI and regular smoking in women who have experimented with cigarettes.     

Smoking Topography in a Nonlaboratory Environment

The relationships between the number of cigarettes smoked/day and the number of puffs/cigarette, puff duration, and total puff time/cigarette were studied. Data were collected on 12 regular smokers for all cigarettes smoked over a 3-day period in a nonlaboratory environment. Between-subject variability was substantial on each of the topographical measures. Neither the number of cigarettes smoked per day nor the classification of Heavy (> 25 cigarettes/day) vs Moderate (< 25 cigarettes/day) smoking levels was related to the intensity with which cigarettes were smoked. Within-subject consistency on the topography measures indicates that smokers may have relatively unique smoking patterns.

Most studies of smoking in the natural environment employ number of cigarettes/day as their estimate of smoke exposure. However, total smoke exposure is determined by an interaction of various topographical features, including frequency (number of cigarettes/day, number of puffs/cigarette), durational (puff duration, interpuff interval, intercigarette interval), and volumetric (puff volume, inhalation volume) components. Employing cigarettes/day to estimate smoke exposure assumes a consistent relationship between cigarettes/day and other topographical features which contribute to total smoke exposure, but it is not clear that such a relationship exists. Laboratory studies of smoking behavior have found that cigarette frequency may vary independently of these other topographic components of smoking, lichtenstein and Antonuccio (1981) examined smoking topography in 24 male smokers while they smoked a cigarette during two 45-minute sessions. They found that cigarette rate was significantly related to intercigarette interval, but not to puff frequency, puff duration, cigarette duration, and amount of tobacco burned.

Results found in laboratory settings, however, have been found not to necessarily generalize to nonlaboratory environments. For example, OssipKlein, Martin, Lomax, Prue, and Davis (1983) examined six subjects smoking adlib in three settings: natural, clinical, and laboratory. They found that cigarette durations were shorter and that subjects took significantly longer and more puffs in a clinical or laboratory setting compared to a naturalistic setting. Thus, examination of the relationship between topographical features in naturalistic smoking would appear to require direct study outside the laboratory.

The present study is to our knowledge the first to examine topographical features of smoking and the relationship between number of cigarettes smoked/ day and other measures of smoking topography while the subject smoked ad-lib in a nonlaboratory environment. This information would potentially be important in examining the extent of individual differences in smoking topography, in assessing the extent to which cigarettes/day is related to other aspects of smoking behavior, and in determining whether categorizing smokers into smoking groups (e.g., moderate and heavy) on the basis of number of cigarettes/day accurately reflects the amount of total smoke exposure/day.     

Smoking-related weight control expectancies among African American light smokers enrolled in a smoking cessation trial

Concern about weight gain following smoking cessation has been frequently described in the literature. However, little is known about smoking-related weight expectancies among African American, light smokers (defined as 25 of last 30 days). Given the high rate of obesity among African Americans, concern about weight gain may be a significant barrier to cessation. The association of demographic, psychosocial and tobacco-related variables and smoking-related weight control expectancies were examined in 755 African American regular, light smokers enrolled in a smoking cessation trial (number of years smoked=23.9+11.9; CPD=7.6+/-3.2; age=45.1+/-10.7; BMI=31+/-8.1; 67% female). Overall, participants had minimal smoking-related weight control expectancies (M=3.7/10, SD+/-3.4); however, higher weight control expectancies were related to female gender, lower dietary fat intake and lower internal self-efficacy to refrain from smoking. Further, smoking-related weight control expectancies were not associated with cessation outcome at week-26. Findings suggest that weight control expectancies exist among some African American light smokers and are related to decreased self-efficacy to refrain from smoking. However, the relationship between smoking-related weight expectancies and health behaviors are complex and modest in magnitude.     

The influence of cigarette smoking on circulating concentrations of antioxidant micronutrients

Cigarette smoke is a significant source of oxidative stress, one potential mechanism for its untoward health effects. The antioxidant defense system is partly comprised of antioxidant micronutrients, making it important to understand the relationship between cigarette smoking and circulating concentrations of antioxidant micronutrients. A synthesis of the literature shows that compared with nonsmokers, on average, active smokers have greater than 25% lower circulating concentrations of ascorbic acid, alpha-carotene, beta-carotene, and cryptoxanthin. The differences in blood concentrations of these micronutrients in former smokers is intermediate between never and current smokers, but average circulating concentrations of alpha-carotene, beta-carotene, and cryptoxanthin were 16-22% lower in former smokers compared with never smokers. Differences in dietary habits between smokers and nonsmokers could potentially account for these associations. Dietary micronutrient intake is associated with blood micronutrient concentrations. Furthermore, patterns of micronutrient consumption by smoking status mimic the pattern of associations observed for blood concentrations. For example, when pooled across studies intake of vitamin C was 16% lower in current smokers and 2% lower in former smokers than in never smokers; the corresponding figures for beta-carotene were 17 and 4%, respectively. Despite the strong potential for confounding, the differences observed between current smokers and nonsmokers seem to be due to an acute effect of smoking based on results of studies of smoking and antioxidant micronutrient concentrations that have either adjusted for dietary antioxidant micronutrient intake and other potential confounding factors or documented short term changes in circulating antioxidant micronutrient concentrations in smokers before and after smoking cigarettes. The associations observed with active smoking also appear to hold true for passive smoking, implying that even low-dose exposures to tobacco smoke can result in lowered circulating antioxidant micronutrient concentrations. Smoking was more weakly associated with circulating concentrations of vitamin E and the nonprovitamin A carotenoids lutein/zeaxanthin and lycopene. The combined evidence supports the conclusion that cigarette smoking is independently associated with lowered circulating concentrations of ascorbic acid and provitamin A carotenoids. These associations have implications for the design and interpretation of epidemiologic studies of antioxidant micronutrients in relation to health and disease. To the extent that these micronutrients are associated with health and longevity, this evidence documents yet another deleterious consequence of cigarette smoking on human health.     

Shorter time to first cigarette of the day in menthol adolescent cigarette smokers

Menthol smoking is thought to contribute to the addictiveness of smoking. Given the high prevalence of menthol smoking among youth, the aim of the current analysis was to examine differences in consumption and tobacco dependence, including smoking urgency among menthol and non-menthol adolescent smokers. Data for the current analysis were collected from telephone interviews with adolescent smokers applying to a cessation treatment study. Of 572 adolescent smokers (mean age=15.6+/-1.6 years; 55.1% female; 46.9% African American, 48.2% European American), 531 smoked menthol cigarettes and 41 smoked non-menthol as their usual brand. Analysis using Fisher's Exact (one-tailed) Test revealed that menthol smokers had a significantly shorter time to first (TTF) cigarette of the day compared to non-menthol smokers (smoking within the first 5 min of the day, 45% vs. 29%, respectively; p<0.04). Independent t tests revealed no significant difference in number of cigarettes per day (CPD) (mean=12.2+/-8.5 vs. 11.4+/-8.8; p<0.28) or Fagerstrom Test for Nicotine Dependence (FTND) scores (3.4+/-1.4 vs. 3.2+/-1.3; p<0.23). While preliminary, our findings suggest greater smoking urgency among menthol compared to non-menthol adolescent cessation-treatment seekers. Further study in a broader sample of adolescent smokers is warranted to elucidate the mechanisms underlying the effects of menthol smoking for youths.     

Measures of initiation and progression to increased smoking among current menthol compared to non-menthol cigarette smokers based on data from four U.S. government surveys

There are no large-scale, carefully designed cohort studies that provide evidence on whether menthol cigarette use is associated with a differential risk of initiating and/or progressing to increased smoking. However, questions of whether current menthol cigarette smokers initiated smoking at a younger age or are more likely to have transitioned from non-daily to daily cigarette use compared to non-menthol smokers can be addressed using cross-sectional data from U.S. government surveys. Analyses of nationally representative samples of adult and youth smokers indicate that current menthol cigarette use is not associated with an earlier age of having initiated smoking or greater likelihood of being a daily versus non-daily smoker. Some surveys likewise provide information on cigarette type preference (menthol versus non-menthol) among youth at different stages or trajectories of smoking, based on number of days smoked during the past month and/or cigarettes smoked per day. Prevalence of menthol cigarette use does not appear to differ among new, less experienced youth smokers compared to established youth smokers. While there are limitations with regard to inferences that can be drawn from cross-sectional analyses, these data do not suggest any adverse effects for menthol cigarettes on measures of initiation and progression to increased smoking.     

Respiratory effects of non-tobacco cigarettes.

Data from the Tucson epidemiological study of airways obstructive disease on smoking of non-tobacco cigarettes such as marijuana were analysed to determine the effect of such smoking on respiratory symptoms and pulmonary function. Among adults aged under 40, 14% had smoked non-tobacco cigarettes at some time and 9% were current users. The prevalence of respiratory symptoms was increased in smokers of non-tobacco cigarettes. After tobacco smoking had been controlled for men who smoked non-tobacco cigarettes showed significant decreases in expiratory flow rates at low lung volumes and in the ratio of the forced expiratory volume in one second to the vital capacity. This effect on pulmonary function in male non-tobacco cigarette smokers was greater than the effect of tobacco cigarette smoking. These data suggest that non-tobacco cigarette smoking may be an important risk factor in young adults with respiratory symptoms or evidence of airways obstruction.     

Investigation into the risk of ultra-low tar cigarettes and lung cancer

We present analyses relating cigarette type to lung cancer based on a case-control study in five European countries. The analyses involved 3561 cases and 2301 controls with diseases not associated with smoking. Subjects completed a detailed questionnaire, including a lifetime smoking history. Analyses included never smokers, and those who smoked for at least 80% of the “critical period” from 2 to 20 years before diagnosis, ignoring those who ever smoked pipes or cigars, or chewed tobacco. The main analysis compares risk in those who, in the critical period, smoked ultra-low tar (ULT) cigarettes (machine yield ≤3 mg tar/cigarette) for 8 + years, with those who only smoked full flavour (FF) cigarettes (≥10 mg tar/cigarette). After adjustment for sex, age, country, education, age of starting smoking, mean cigarette consumption and mean tar level 21–50 years before interview, the odds ratio (OR) was 0.73 (95% confidence interval (CI) 0.50–1.06). Other analyses showed a modest, not statistically significant, reduction in risk with tar reduction. Risk in ULT smokers for 8 + years was substantially higher than in never smokers (OR 16.27, 95% CI 10.14–26.09). The study was prematurely terminated due to cost overrun, limiting the power to detect an association. More evidence is needed, particularly on lifetime ULT smoking.     

Heterogeneity of intermittent smokers in a Hispanic college student sample

Hispanics are more likely to be daily light smokers (DLS) and intermittent smokers (ITS) than non-Hispanic whites. Although daily light (≤10 cigarettes per day [CPD]) and intermittent (nondaily) smoking have increased in recent years, few studies have compared DLS and ITS, especially within a Hispanic sample. The primary aims of this study were to investigate differences between DLS and ITS, and within ITS, differences between converted ITS (CITS; previously smoked daily for ≥6 months) and native ITS (NITS; never smoked daily) in a Hispanic college student sample (M_age = 23.74, SD = 5.17; 58.1% male). Analyses were conducted using baseline data from a larger study that evaluated attitudes toward tobacco free campus policies in a U.S. university on the border with México. This study included data from 45 DLS and 216 ITS (CITS: n = 77, NITS: n = 139; N = 261). Compared to DLS, ITS were younger (on average), less likely to identify as smokers, smoked on fewer days in the past month, smoked fewer cigarettes on smoking days, and reported less nicotine dependence. Compared to CITS, NITS were younger, less likely to self-identify as smokers, smoked on fewer days in the past month, smoked fewer CPD on smoking days, and were less dependent on nicotine. Given the similarities between current and past findings (suggesting that CITS are in between DLS and NITS—regarding smoking behavior), these data suggest a similar pattern likely exists also among Hispanic smokers. Additionally, the absence of some previously observed differences is relevant in characterizing this particular Hispanic college sample. These findings provide further insight for the tailoring of interventions that target Hispanic DLS, CITS and NITS).     

The effect of cigarette burn time on exposure to nicotine and carbon monoxide in adult smokers

Cigarette burn time (CBT), conventionally defined as the time a cigarette burns during smoking, can be affected by cigarette design and smoking behavior. A previous study showed a strong negative correlation between CBT and nicotine yield under machine smoking conditions. This study for the first time examined the relationship of CBT and exposure to nicotine and carbon monoxide in adult smokers in a controlled clinical study. 24h nicotine equivalents excretion (NE), carboxyhemoglobin (COHb) and CBT were measured in two groups of 20 adults smoking Marlboro Lights and 20 adults smoking Marlboro Ultra on two consecutive days. Approximately 20% of the total variability in CBT was attributed to cigarette brand, 34% to smokers and 1% to study day. The exposure index, defined as the number of cigarettes smoked per day divided by average daily CBT for each smoker, accounted for a large proportion of the total variability in NE (R(2)=0.79-0.91) and COHb (R(2)=0.85-0.90). We conclude that CBT has an important influence on levels of NE and COHb in adult smokers. CBT, along with the number of cigarettes smoked per day, can be used to estimate adult smokers' exposure to nicotine and carbon monoxide.     

Evaluating the association between menthol cigarette use and the likelihood of being a former versus current smoker

Menthol in cigarettes has been examined for its potential to affect smoking dependence, measured primarily as number of cigarettes smoked per day and time to first cigarette after waking; the ability to quit smoking constitutes an additional measure of dependence. Successful quitting among menthol compared to non-menthol cigarette smokers is difficult to determine from the literature, due in part to the various definitions of quitting used by researchers. Nevertheless, intervention and follow-up studies of smoking cessation treatments generally indicate no differences in quitting success among menthol compared to non-menthol smokers, while cross-sectional studies suggest some differences within race/ethnicity groups. The association between menthol cigarette use and likelihood of being a former versus current smoker was examined based on data from the National Health Interview Survey and Tobacco Use Supplement to the Current Population Survey. Analyses stratified by race/ethnicity and limited to smokers who had quit at least one year prior to survey participation provided inconsistent results with regard to menthol cigarette use and quitting, both within surveys (i.e., comparing race/ethnicity groups) and between surveys (i.e., same race/ethnicity group across surveys). Evidence suggesting the existence or direction of an association between menthol in cigarettes and quitting depended on the data source.     

Cigarette smoking duration mediates the association between future thinking and norepinephrine level

Fixating on the present moment rather than considering future consequences of behavior is considered to be a hallmark of drug addiction. As an example, cigarette smokers devalue delayed consequences to a greater extent than nonsmokers, and former smokers devalue delayed consequences more than nonsmokers, but less than current smokers. Further, cigarette smokers have higher norepinephrine levels than nonsmokers, which is indicative of poor future health outcomes. It is unclear how duration of cigarette smoking may impact these associations. The current secondary analysis of publicly available data investigated whether extent of future thinking is associated with smoking duration, as well as norepinephrine level, in a large national US sample (N = 985) of current, former, and never smokers. Individuals scoring lower on future thinking tended to smoke for longer durations and had higher norepinephrine levels relative to individuals scoring higher on future thinking. In addition, duration of cigarette abstinence interacted significantly with future thinking and smoking duration for former smokers. Specifically, the mediation relationship between future thinking, smoking duration, and norepinephrine level for former smokers was strongest at shorter durations of cigarette abstinence and decreased as a function of increasing duration of cigarette abstinence. Overall, results from this study suggest the potential importance of implementing smoking cessation treatments as early as possible for smokers and support future thinking as a potential therapeutic target for smoking cessation treatment.     

Smoking behavior and motivational flexibility in light and heavy smokers

Little is known about the consistency of people's reasons for smoking and how these might influence the amount of smoking in individuals. Therefore, we developed a new concept, motivational flexibility, which suggests that a behavior is more common when people have multiple reasons for engaging in it and when the primary reason changes across occurrences of the behavior. The purpose of this study was to examine motivational flexibility in cigarette smokers. We hypothesized that smoking would be associated with greater number of reasons for smoking and greater frequency of change (shifting) in the most important motive for smoking among light smokers. Student cigarette smokers (N=116) completed daily entries for 14 days: whether they smoked or not and their reasons for doing so, with importance ratings for each reason listed. Multilevel modeling was used to examine the relationship between motivational flexibility and daily cigarette smoking. Shifting among the most important motive over the 14-day assessment was associated with greater frequency of smoking in light but not daily smokers. Also, smoking for craving and social reasons was associated with smoking fewer cigarettes and on fewer days. Results confirm the applicability of the motivational flexibility concept to smoking. The association between motive shifting and greater frequency of smoking may indicate a greater responsiveness to environmental cues. That we found this association in light but not daily smokers who are likely addicted to cigarettes may indicate that light smokers are affected more by triggers for smoking, or that they may rationalize their smoking behavior more than heavier smokers.     

Acute psychomotor,subjective and physiological responses to smoking in depressed outpatient smokers and matched controls

Rationale Cigarette smoking is highly prevalent in people diagnosed with depression, and depressed smokers are less likely to quit. Examining depressed smokers’ responses to smoking will help determine the role of depression in maintaining cigarette smoking. Objectives To determine the psychomotor, subjective and physiological effects of cigarette smoking in currently depressed smokers versus matched controls. Materials and methods Fourteen currently depressed smokers and 14 never-depressed smokers, matched in age, gender, nicotine dependence and daily cigarette consumption, smoked three cigarettes at half-hourly intervals. All smokers were non-deprived. Self-reported mood and craving for cigarettes, performance on a simple reaction time task, expired-air carbon monoxide, heart rate and blood pressure were assessed before and after smoking each cigarette. Smoking topography was also assessed. Results Depressives and controls did not differ in terms of dependence on cigarettes or expired-air carbon monoxide. Topographic and cardiovascular measures were similar in depressed and control participants, suggesting that they smoke cigarettes in a similar manner. However, depressives displayed enhanced reaction time performance after the first cigarette. Positively reinforced craving was reduced after smoking each cigarette but returned to baseline levels within 30 min in depressed but not in control smokers. Depressed smokers also displayed higher levels of negatively reinforced craving. Both depressives and controls reported improved positive mood after smoking. Conclusions Cigarette smoking in non-deprived depressed smokers enhances psychomotor performance and the reduction of positively reinforced craving in depressed smokers after smoking is transient, suggesting that enhanced craving may play a role in the maintenance of smoking in depression.     

The effects of cigarette smoking on plasma concentrations of gastric antisecretory drugs

Plasma concentrations of cimetidine and ranitidine were measured after oral administration (n = 5 for cimetidine, n = 5 for ranitidine) or intravenous administration (n = 6 for cimetidine, n = 4 for ranitidine) in habitual smokers, once when cigarettes were smoked and again on a separate day when cigarettes were prohibited. After oral administration plasma concentrations of both drugs rose more rapidly and peak plasma concentrations were achieved earlier when cigarettes were smoked. However, plasma concentrations of the drugs subsequent to the peak were significantly lower when cigarettes were smoked. Cigarette smoking had no effect on plasma blood concentrations of either drug when administered intravenously. In eight healthy smokers cigarette smoking increased the gastric emptying of a liquid test meal by 28% compared with non-smoking control rates. In habitual smokers cigarette smoking alters the blood concentrations of antisecretory drugs in a manner which appears attributable to an increase in the rate of gastric emptying. The observed changes in drug disposition may contribute to the loss of gastric secretory inhibition observed in duodenal ulcer patients who are smokers.