Project description:Among cigarette smokers, lower levels of consumption, defined as smoking fewer cigarettes per day (CPD) or not smoking daily, are becoming more common. The relationship between cigarette consumption and smoking frequency (daily or nondaily) is not well characterized, and the natural history of light smoking (defined here as smoking < or =10 CPD) is poorly understood.We assessed changes in CPD and smoking frequency over time among light smokers (< or =10 CPD) and very light smokers (< or =5 CPD), using a population-based longitudinal survey of 3,083 adult smokers in Massachusetts who were interviewed three times over a 4-year follow-up period (in 2000-2001, 2002-2003, and 2005-2006). We used logistic regression to identify factors associated with light smokers' progression to heavier smoking or smoking reduction/quitting.Seventy percent of very light smokers were nondaily smokers. Very light nondaily smokers differed from very light daily smokers by younger age, higher socioeconomic status, a social smoking pattern, later smoking initiation, less evidence of nicotine addiction, and more recent and planned cessation efforts. Very light nondaily smokers and smokers consuming 6-10 CPD were more likely to remain in the same smoking category and were less likely to increase consumption than were very light daily smokers. Factors independently associated with increasing consumption among very light smokers were smoking daily, nicotine dependence, White ethnicity, social smoking, and having more friends who smoked; among smokers consuming 6-10 CPD, male gender and lack of quitting self-efficacy were associated with increasing consumption.Our findings indicate that most light smoking is not a gateway to heavier smoking.
Project description:While most college students and other young adults who smoke fall into the light and intermittent smoking (LITS) category, they remain at risk for tobacco dependence and other adverse health effects from their smoking. This study examines smoking patterns, tobacco dependence, and other health variables among students at five universities to better understand how to identify and address tobacco use and related risks in a college health clinic setting.A health screening survey was completed by 2,091 college and graduate student volunteers seeking routine care at their university health centers or participating in a health class. Independent health variables were analyzed descriptively and in regression analyses with three levels of smoking (none, non-daily, and daily) and tobacco dependence to determine predictors and associated risks.Nearly a quarter of students reported any current smoking, 41% of whom reported smoking less than 1 cigarette/day (cpd). Of the daily smokers, 80% smoked less than 10 cpd but 45% met criteria for tobacco dependence. Any smoking was associated with high-risk alcohol use, risky driving, relational abuse, depression, less exercise, and utilization of emergency and mental health services. In regression analyses, students who experienced depression had more than double the odds of being dependent smokers (odds ratio [OR] = 2.32), as did those who reported abuse (OR = 2.07) or sought mental health counseling (OR = 2.09).Student health providers should be alerted to the multiple risks and comorbidities that occur among all smokers, including LITS, and intervene concurrently to help prevent or mitigate adverse outcomes that result from these conditions and behaviors.
Project description:Light and intermittent patterns of cigarette smoking are prevalent among U.S. college-aged individuals. It is unclear whether intermittent smokers maintain their use over time or are transitioning to daily use or nonuse, and whether they experience more adverse health outcomes than nonsmokers.This study examined the trajectories of tobacco cigarette smoking, their predictors, and health outcomes among students (N = 1,253) assessed during their first year of college (Y(1)) and annually thereafter (Y(2), Y(3), and Y(4)).In Y(1), 3.4% smoked daily and 4.1% exhibited signs of dependence (first cigarette within 30 min of waking). Growth curve modeling identified five distinct smoking trajectories. After stable nonsmokers (71.5%(wt)), the low-stable smoking trajectory was the most common (13.3%(wt)), outnumbering both low-increasing (6.5%(wt)) and high-stable smokers (5.5%(wt)) by 2:1 and high-decreasing smokers (3.2%(wt)) by 4:1. The likelihood of maintaining a low level of smoking over time was inversely related to Y(1) smoking frequency. Few demographic, smoking, and alcohol use characteristics measured in Y(1) distinguished low-increasers from low-stable smokers or high-decreasers from high-stable smokers. By Y(4), high-stable smokers rated their health significantly worse than all others except low-increasers. High-stable smokers had the most Y(4) health problems (i.e., provider visits for health problems and days of illness-related impairment), but only among nonWhites.Many college students smoke, but few smoke daily or are nicotine dependent. Intermittent smoking patterns are often stable throughout college and are associated with adverse health outcomes. Prevention strategies should be designed to mitigate the possible long-term health consequences of light and intermittent smoking.
Project description:Current theoretical models of nicotine dependence assume a close relationship between use and dependence; however, previous data suggest that many daily smokers fail to develop nicotine dependence.To determine what percentage of daily smokers fail to meet DSM-IV criteria for nicotine dependence within their lifetime, how non-dependence relates to duration and quantity of cigarette use, and whether other tobacco use and/or specific dependence criteria differentiate never-dependent and dependent smokers.Cross-sectional data collected via personal interview from a nationally representative sample of 8213 past year daily smokers were analyzed.Approximately 39.4% of daily smokers never reached nicotine dependence. While the probability of remaining non-dependent decreased with smoking quantity and duration since the onset of daily smoking, a substantial portion of individuals (37.7%) who reported smoking >or=10 cigarettes per day and began smoking daily >or=10 years prior, remained never nicotine dependent.The absence of nicotine dependence in heavy daily smokers may result from limitations in the measurement of dependence and/or nicotine exposure. Alternatively, some individuals may be relatively resistant to becoming nicotine dependent despite extensive use. The latter explanation would have important implications for understanding the nature of nicotine dependence.
Project description:Racial/ethnic disparities in cigarette use and cessation persist. This study compared cigarette consumption and former smoking trends in California (CA) with the rest of the United States (US) by racial/ethnic categories of non-Hispanic White, Black, Hispanic/Latino, and Asian/Pacific Islander groups. Data were analyzed from the 1992 to 2011 Tobacco Use Supplement to the Current Population Survey. Consumption levels across decades were examined and adjusted logistic regression models were fit to compare across CA and US. Results indicated steady declines in ever smoking prevalence for all groups with much lower magnitudes of change among US Blacks and Whites compared to their CA counterparts. After controlling for age, gender, and education, CA had significantly fewer heavy smokers (OR=0.45, 95% CI:0.38-0.54), more light and intermittent smokers (LITS; OR=1.68, 95%CI: 1.45-1.93), and a greater proportion of former smokers (OR=1.35, 95%CI: 1.24-1.48) than the rest of US. Data were stratified by race/ethnicity and the patterns shown were mostly consistent with CA performing statistically better than their US counterparts with the exception of Black LITS and Asian/Pacific Islander former smokers. California's success in reducing tobacco use disparities may serve as a prime example of tobacco control policy for the country. CA and the US will need to continue to address tobacco use and cessation in the context of the growing diversity of the population.
Project description:As many as half of intermittent (i.e., nondaily) smokers once smoked daily. Little is known about their transition from daily to intermittent smoking, a process that eventually leads them to forego smoking on some days.The present study attempted to gain insight by analyzing situations in which these individuals were likely to smoke. It used data from a California population tobacco survey with a supplemental questionnaire on smoking situations of young adults (aged 18-29 years, n = 1,581). The analysis in the present study divided smokers into three groups: daily smokers, intermittent smokers who never smoked daily (never-daily intermittent), and intermittent smokers who formerly smoked daily (former-daily intermittent).Former-daily intermittent smokers were more similar to never-daily intermittent smokers than to daily smokers in seven types of smoking situation, regardless of whether the situations were more social and episodic, such as "at parties," or more routine, such as while "driving." This held true even though these former-daily intermittent smokers were daily smokers only about 22 months on average before the survey. It appears that former-daily intermittent smokers reduce their probability of smoking across all situations.We propose a simple model to explain how a reduction in smoking probability across all situations might lead former-daily intermittent smokers to first forego smoking on days with no social events. The fact that smokers frequently go from daily to nondaily smoking has both theoretical and practical implications for nicotine research and for public health campaigns to reduce tobacco-related diseases.
Project description:The current study examined the moderating effects of smoking amount per day on the relation between anxiety sensitivity and nicotine dependence, cigarette smoking outcome expectancies, and reasons for quitting smoking among 465 adult, treatment-seeking smokers (48% female; Mage = 36.6, SD = 13.5). Smoking amount per day moderated the relation between anxiety sensitivity and nicotine dependence, smoking expectancies for negative consequences and appetite control as well as intrinsic reasons for quitting. However, no moderating effect was evident for negative reinforcement expectancies. The form of the significant interactions indicated across dependent variables lower levels of smoking amount per day suppressed the relation between anxiety sensitivity and smoking related dependent variable, such that the positive relation of anxiety sensitivity to smoking dependence and cognitive-affective aspects of smoking is weaker in heavier smokers and more robust in lighter smokers.
Project description:Although established smokers have a very regular pattern of smoking behavior, converging lines of evidence suggest that the escalation of smoking behavior is a critical factor in the development of dependence. However, the neurobiological mechanisms that underlie the escalation of smoking are unknown, because there is no animal model of the escalation of nicotine intake. On the basis of the pattern of smoking behavior in humans and presence of monoamine oxidase inhibitors in tobacco smoke, we hypothesized that the escalation of nicotine intake may only occur when animals are given extended-access (21 h per day) self-administration sessions after repeated periods of abstinence (24-48 h), and after chronic inhibition of monoamine oxidase using phenelzine sulfate. Intermittent access (every 24-48 h) to extended nicotine self-administration produced a robust escalation of nicotine intake, associated with increased responding under fixed- and progressive-ratio schedules of reinforcement, and increased somatic signs of withdrawal. The escalation of nicotine intake was not observed in rats with intermittent access to limited (1 h per day) nicotine self-administration or daily access to extended (21 h per day) nicotine self-administration. Moreover, inhibition of monoamine oxidase with daily administration of phenelzine increased nicotine intake by ? 50%. These results demonstrate that the escalation of nicotine intake only occurs in animals given intermittent periods of abstinence with extended access to nicotine, and that inhibition of monoamine oxidase may contribute to the escalation of smoking, thus validating both an animal model of the escalation of smoking behavior and the contribution of monoamine oxidase inhibition to compulsive nicotine-seeking.
Project description:BACKGROUND:Socioeconomic status (SES) is a major determinant of tobacco use but little is known whether SES affects nicotine exposure and the degree of nicotine dependence. METHODS:The Pennsylvania Adult Smoking Study is a cross-sectional study of smoke exposure and nicotine dependence among adults conducted in central Pennsylvania between June 2012 and April 2014. The study included several measures of SES, including assessments of education and household income, as well as occupation, home ownership, health insurance, household density and savings accounts. Measurements included saliva for the nicotine metabolites cotinine (COT), 3-'hydroxycotinine (3HC) and total metabolites (COT +3HC). Puffing behavior was determined using portable smoking topography devices. RESULTS:The income levels of lighter smokers (< 20 cigarettes per day) was $10,000 more than heavier smokers. Higher Fagerström Test for Nicotine Dependence scores were associated with lower income and job status, scores ranged from 5.4 in unemployed, 4.4 in blue-collar, and 3.8 in white-collar workers. In principal components analysis used to derive SES indicators, household income, number in household, and type of dwelling were the major SES correlates of the primary component. Job category was the major correlate of the second component. Lower SES predicted significantly higher adjusted total nicotine metabolite levels in the unemployed group. Job category was significantly associated with total daily puffs, with the highest level in the unemployed, followed by blue-collar workers, after adjustment for income. CONCLUSIONS:Among smokers, there was a relationship between lower SES and increased nicotine dependence, cigarettes per day and nicotine exposure, which varied by job type.
Project description:INTRODUCTION:Non-daily intermittent smokers (ITS) comprise 30% of US adult smokers. ITS smoke for nicotine and have trouble quitting, but tend to smoke in particular situations. This study tested the effect of nicotine gum, used to prevent or react to situational temptations, for helping ITS quit. METHODS:ITS (smoking 4-27 days/month) seeking help quitting were randomized to 2 mg nicotine gum (n = 181) or placebo (n = 188), to be used to anticipate or react to temptations to smoke, for 8 weeks. Participants received up to six sessions of behavioral counseling. The primary outcome was 6-month biochemically verified continuous abstinence; analyses also examined 14-day point-prevalence abstinence at multiple time points, and used event-history analyses to assess progression to abstinence, lapsing, and relapsing. Analyses adjusted for group differences in age and baseline smoking, and considered several potential moderators of treatment effects. RESULTS:Nicotine gum did not significantly improve outcomes on any measure. Biochemically verified 6-month continuous abstinence rates were 7.2% for active gum and 5.3% for placebo (AOR = 1.39, 0.58-3.29, p > .25). ITS with any degree of dependence (Fagerstrom Test of Nicotine Dependence scores >0) showed poorer outcomes on multiple endpoints, and did more poorly on active gum on some outcomes. Gum use was low, starting at 1 gum per day on average and declining over time. CONCLUSIONS:Nicotine gum (2 mg), used intermittently, did not improve cessation rates among ITS, including those demonstrating some degree of dependence. IMPLICATIONS:Nicotine replacement has been extensively tested with daily smokers, especially those who smoke relatively heavily. Nondaily smoking is now common, creating a need for treatment for ITS. Despite evidence that ITS' smoking is motivated by nicotine-seeking, a theoretically and empirically derived situational approach to using acute nicotine replacement was not successful at helping ITS quit. Gum use was low; whether higher or more frequent dosing is needed, or whether an entirely different approach is needed, is not clear. Effective treatment options are needed for ITS, especially those with some degree of dependence.