Stability of smoking status in the US population: a longitudinal investigation

The role of sex hormones in targeting stress-induced tobacco craving, stress-reactivity, and smoking with guanfacine among women who smoke

Women who smoke are particularly vulnerable to tobacco craving, smoking behaviors, and relapse in the context of stress when compared to men who smoke. One factor in this sex difference may be sex hormones, including estradiol and progesterone; however, smoking cessation medication trials often do not explore the impact of sex hormones on drug effects. This secondary analysis of a double-blind, placebo-controlled study explored the impact of levels of actual estradiol and progesterone on guanfacine, a noradrenergic α2a agonist, which attenuates stress-induced smoking behaviors in women. Women who smoke (n = 43) completed a stress induction laboratory paradigm followed by an ad-libitum smoking period. Assessment of tobacco craving, and stress-reactivity (via cortisol response) occurred pre- and post-stress induction. Results indicated that guanfacine attenuated stress-induced tobacco craving (F = 10.94, p = 0.02) and cortisol response (F = 14.23, p < 0.001); however, high levels of estradiol overrode guanfacine's effect on craving (F = 4.00, p = 0.05), cortisol response (F = 14.23, p < 0.001), and smoking during the ad-libitum period (F = 12.23, p = 0.001). Additionally, progesterone proved to be protective against tobacco craving and enhanced guanfacine's medication effect on craving (F = 5.57, p = 0.02). The present study found that sex hormones had a significant impact on medication effects in a smoking cessation trial and thus underscore the importance of examining the role of sex hormones in future medication trials.

Changes in Smoking Behavior Before and After Gastric Bypass: A 7-year Study

OBJECTIVE

To evaluate smoking history and change in smoking behavior, from 1 year before through 7 years after Roux-en-Y gastric bypass (RYGB) surgery, and to identify risk factors for post-surgery smoking.

BACKGROUND

Smoking behavior in the context of bariatric surgery is poorly described.

METHODS

Adults undergoing RYGB surgery entered a prospective cohort study between 2006 and 2009 and were followed up to 7 years until ≤2015. Participants (N = 1770; 80% female, median age 45 years, median body mass index 47 kg/m2) self-reported smoking history pre-surgery, and current smoking behavior annually.

RESULTS

Almost half of participants (45.2%) reported a pre-surgery history of smoking. Modeled prevalence of current smoking decreased in the year before surgery from 13.7% [95% confidence interval (CI) = 12.1-15.4] to 2.2% (95% CI = 1.5-2.9) at surgery, then increased to 9.6% (95% CI = 8.1-11.2) 1-year post-surgery and continued to increase to 14.0% (95% CI = 11.8-16.0) 7-years post-surgery. Among smokers, mean packs/day was 0.60 (95% CI = 0.44-0.77) at surgery, 0.70 (95% CI = 0.62-0.78) 1-year post-surgery and 0.77 (95% CI = 0.68-0.88) 7-years post-surgery. At 7-years, smoking was reported by 61.7% (95% CI = 51.9-70.8) of participants who smoked 1-year pre-surgery (n = 221), 12.3% (95% CI = 8.5-15.7) of participants who formerly smoked but quit >1 year pre-surgery (n = 507), and 3.8% (95% CI = 2.1-4.9) of participants who reported no smoking history (n = 887). Along with smoking history (ie, less time since smoked), younger age, household income <$25,000, being married or living as married, and illicit drug use were independently associated with increased risk of post-surgery smoking.

CONCLUSION

Although most adults who smoked 1-year before RYGB quit pre-surgery, smoking prevalence rebounded across 7-years, primarily due to relapse.

Urinary cadmium and stroke - a case-cohort study in Danish never-smokers

BACKGROUND

and Purpose: Cadmium has been associated with risk of cardiovascular events, including stroke. Human cadmium exposure occurs primarily through diet and tobacco smoke. Recent cohort studies have found an association with stroke, but residual confounding from smoking, could not be ruled out. We therefore conducted a case-cohort study to evaluate whether cadmium is associated with stroke in never-smokers.

METHODS

The Danish Diet Cancer and Health cohort consists of Danes 50-64 years old, recruited in 1993-1997. From never-smoking cohort members without previous cancer or stroke we sampled a sub-cohort of 1200 persons. We also identified all (n = 534) cases in the cohort with a validated stroke diagnosis between baseline and 2009. We quantified cadmium and creatinine concentrations from baseline urine samples and used cadmium per creatinine as our main exposure metric. We used Cox proportional hazards models to estimate hazard ratios (HRs) with age as time scale and adjusting for BMI, education and urinary cotinine with and without stratification by sex.

RESULTS

The median urinary cadmium concentration was 0.21 μg cadmium/g creatinine in cases and 0.19 μg/g in the sub-cohort. The majority (83%) of stroke cases were diagnosed with ischemic stroke. The HR for stroke in the highest quartile of exposure (median 0.44 μg/g creatinine) was 1.11 (95% CI: 0.79-1.54) compared with the lowest quartile (median 0.10 μg/g creatinine). The HR per inter quartile range (IQR, 0.19 μg/g creatinine) was 1.02 (95% CI: 0.92-1.12). Among men, the HR per IQR higher levels of cadmium (0.16 μg/g creatinine) was 1.18 (95% CI: 0.92-1.52), and 1.00 (95% CI: 0.89-1.12) among women. Adjusting for creatinine or using osmolality instead of creatinine standardization generally attenuated observed relationships.

CONCLUSIONS

Our results do not support that low levels of cadmium exposure among never-smokers are strongly associated with risk of stroke, although results varied somewhat by sex and method of accounting for urinary dilution.

Sex Differences in the Ventral Tegmental Area and Nucleus Accumbens Proteome at Baseline and Following Nicotine Exposure

Sex differences in behaviors relevant to nicotine addiction have been observed in rodent models and human subjects. Behavioral, imaging, and epidemiological studies also suggest underlying sex differences in mesolimbic dopamine signaling pathways. In this study we evaluated the proteome in the ventral tegmental area (VTA) and nucleus accumbens (NAc) shell in male and female mice. Experimental groups included two mouse strains (C3H/HeJ and C57BL/6J) at baseline, a sub-chronic, rewarding regimen of nicotine in C3H/HeJ mice, and chronic nicotine administration and withdrawal in C57BL/6J mice. Isobaric labeling with a TMT 10-plex system, sample fractionation, and tandem mass spectrometry were used to quantify changes in protein abundance. In C3H/HeJ mice, similar numbers of proteins were differentially regulated between sexes at baseline compared with within each sex after sub-chronic nicotine administration. In C57BL/6J mice, there were significantly greater numbers of proteins differentially regulated between sexes at baseline compared with within each sex after chronic nicotine administration and withdrawal. Despite differences by sex, strain, and nicotine exposure parameters, glial fibrillary acidic protein (GFAP) and dopamine and cAMP-regulated phosphoprotein of 32 kDa (DARPP-32, Ppp1r1b) were repeatedly identified as significantly altered proteins, especially in the VTA. Further, network analyses showed sex- and nicotine-dependent regulation of a number of signaling pathways, including dopaminergic signaling. Sub-chronic nicotine exposure in female mice increased proteins related to dopaminergic signaling in the NAc shell but decreased them in the VTA, whereas the opposite pattern was observed in male mice. In contrast, dopaminergic signaling pathways were similarly upregulated in both male and female VTA after chronic nicotine and withdrawal. Overall, this study identifies significant sex differences in the proteome of the mesolimbic system, at baseline and after nicotine reward or withdrawal, which may help explain differential trajectories and susceptibility to nicotine addiction in males and females.

The effect of smoking on depressive symptoms

BACKGROUND

People who smoke tend to report higher levels of psychological distress than those who do not smoke. However, studies suggest that smoking reduces many sub-dimensions of distress, including depressive symptoms. A negative (i.e. depression reducing) effect of smoking on depressive symptoms might be observed in survey panel data only after adjustment for the effect of depressive symptoms on smoking. Results from analyses that make that adjustment are presented within groups jointly defined by race and gender, and for all respondents in a representative sample of the U.S.

POPULATION

METHOD

Reciprocal effects of smoking and depressive symptoms (DSx) are estimated with dynamic panel models. Data are from the Americans' Changing Lives study which assessed smoking and depressive symptoms five times over 25 years. Additional analyses provide estimates of effect of continuing to smoke versus quitting.

RESULTS

The estimated effect of smoking on DSx after adjustment for the simultaneous effect of DSx on smoking and unobserved confounders is negative among women. The estimated effect among men is not statistically significant, and no race difference is observed.

CONCLUSIONS

The tendency for smoking to reduce depressive symptoms among American women is masked in analyses that fail to account for the reciprocal effect of depressive symptoms on smoking.

Intersection of E-Cigarette Use and Gender on Transitions in Cigarette Smoking Status: Findings Across Waves 1 and 2 of the Population Assessment of Tobacco and Health Study

INTRODUCTION

Cigarette smokers report using electronic cigarettes (e-cigarettes) to reduce or quit smoking, but findings are mixed regarding the benefit and risk of e-cigarettes in this population, and effects of gender are unknown.

METHODS

The Population Assessment of Tobacco and Health (PATH; waves 1 and 2; adult interviews) was used to evaluate relationships among wave 1 e-cigarette use (daily, nondaily, never) and gender and their association with transitions (quit vs. current; relapse vs. former) in cigarette smoking status across waves 1 and 2 of the PATH study.

RESULTS

Daily e-cigarette users had higher odds of quitting smoking (odds ratio [OR] = 1.56, 95% confidence interval [CI] = 1.12 to 2.18) compared with never e-cigarette users. Conversely, daily and nondaily e-cigarette users were at greater risk of smoking relapse (OR = 1.84, 95% CI = 1.15 to 2.94 and OR = 1.85, 95% CI = 0.99 to 3.46, respectively) compared with never e-cigarette users. Women were less likely to quit smoking compared with men independent of e-cigarette use (OR = 0.76, 95% CI = 0.59 to 0.99). In stratified analyses, daily or nondaily e-cigarette use did not increase the likelihood of quitting or relapse in women. In men, daily and nondaily e-cigarette users were at greater risk of smoking relapse (OR = 2.96, 95% CI = 1.49 to 5.86 and OR = 3.05, 95% CI = 1.29 to 7.17, respectively) compared with men who were never e-cigarette users.

CONCLUSIONS

Findings identify e-cigarettes as a potential aid for smoking cessation but also as a potential risk for smoking relapse in men only. Overall, women were less likely to quit smoking, and e-cigarette use did not impact their ability to quit or to stay quit.

IMPLICATIONS

Cigarette smokers report using e-cigarettes to reduce or quit smoking, but findings are mixed regarding the benefit and risk of e-cigarettes in this population. Using data from the newly available PATH (waves 1 and 2; adult interviews), our findings identify e-cigarettes as a potential aid for smoking cessation but also identify e-cigarettes as a potential risk for smoking relapse in men only. These findings may have implications for the regulation of e-cigarettes by the Food and Drug Administration and the benefit-cost ratio of e-cigarette use in smokers.

The influence of gender and oxytocin on stress reactivity, cigarette craving, and smoking in a randomized, placebo-controlled laboratory relapse paradigm

RATIONALE

Female cigarette smokers tend to show greater cessation failure compared with males. Variables that contribute to the maintenance of smoking, including stress and craving, may differentially impact male and female smokers. Novel pharmacotherapies, such as oxytocin, may attenuate stress reactivity and craving in smokers, but work in this area is limited.

OBJECTIVES

This study assessed the influence of gender and oxytocin on stress reactivity, craving, and smoking in a randomized, placebo-controlled laboratory relapse paradigm.

METHODS

Male and female adult cigarette smokers (ages 18-45) were enrolled (women oversampled 2:1) and completed a laboratory session, in which intranasal oxytocin or placebo was administered followed by a laboratory social stress task. The role of gender and oxytocin were assessed on measures of stress reactivity, cigarette craving, latency to smoke in a resistance task, subjective responses to smoking, and ad-libitum smoking.

RESULTS

Participants (N = 144) had a mean age of 31 were 63% female and 56% White. Following stress induction, female smokers evidenced greater subjective stress than males, though males demonstrated greater neuroendocrine reactivity and smoking intensity than females. No gender differences were demonstrated for craving. Oxytocin did not attenuate any aspect of stress reactivity, craving, smoking, or subjective responses to smoking compared with placebo.

CONCLUSIONS

Gender differences in stress reactivity were shown in the hypothesized direction, but oxytocin appeared to exert little impact on subjective or behavioral metrics. Results highlight the complex relationship between gender, stress, and smoking, as well as the implications for oxytocin as a potential pharmacotherapy for smoking cessation.

Is Healthy Neuroticism Associated with Health Behaviors? A Coordinated Integrative Data Analysis

Current literature suggests that neuroticism is positively associated with maladaptive life choices, likelihood of disease, and mortality. However, recent research has identified circumstances under which neuroticism is associated with positive outcomes. The current project examined whether "healthy neuroticism", defined as the interaction of neuroticism and conscientiousness, was associated with the following health behaviors: smoking, alcohol consumption, and physical activity. Using a pre-registered multi-study coordinated integrative data analysis (IDA) approach, we investigated whether "healthy neuroticism" predicted the odds of engaging in each of the aforementioned activities. Each study estimated identical models, using the same covariates and data transformations, enabling optimal comparability of results. These results were then meta-analyzed in order to estimate an average (N-weighted) effect and to ascertain the extent of heterogeneity in the effects. Overall, these results suggest that neuroticism alone was not related to health behaviors, while individuals higher in conscientiousness were less likely to be smokers or drinkers, and more likely to engage in physical activity. In terms of the healthy neuroticism interaction of neuroticism and conscientiousness, significant interactions for smoking and physical activity suggest that the association between neuroticism and health behaviors was smaller among those high in conscientiousness. These findings lend credence to the idea that healthy neuroticism may be linked to certain health behaviors and that these effects are generalizable across several heterogeneous samples.

Increasing Depression and Substance Use Among Former Smokers in the United States, 2002-2016

INTRODUCTION

Mental health and substance use problems are associated with smoking relapse among former smokers. Yet, little is known about the prevalence of mental health and substance use among former smokers in the U.S. In addition, it is unknown whether the prevalence of these conditions has changed over time as former U.S. smokers have grown to outnumber current U.S. smokers. This study, which was conducted in 2018 and 2019, examined the prevalence and trends over time in depression (2005-2016), marijuana use (2002-2016), and alcohol use problems (2002-2016) among former U.S. smokers.

METHODS

The National Survey on Drug Use and Health is an annual, nationally representative, cross-sectional study. Data from U.S. individuals who were aged ≥18 years in 2002-2016 were included. Former smokers were defined as having smoked ≥100 lifetime cigarettes and no past-year cigarettes.

RESULTS

From 2005 to 2016, the prevalence of major depression increased from 4.88% to 6.04% (AOR=1.01, 95% CI=1.00, 1.03, p=0.04). From 2002 to 2016, past-year marijuana use rose from 5.35% to 10.09% (AOR=1.08, 95% CI=1.07, 1.09, p<0.001) among former smokers. Past-month binge alcohol use also increased from 17.22% to 22.33% (AOR=1.03, 95% CI=1.02, 1.04, p<0.001), although the prevalence of past-year alcohol abuse or dependence did not change.

CONCLUSIONS

Depression and substance use, which are factors associated with increased risk for cigarette use relapse, appear to be increasing over time among former U.S. smokers. Increased awareness of these trends may be important for clinical and public health efforts to direct attention to conditions potentially threatening sustained abstinence among former smokers.

Exogenous progesterone for smoking cessation in men and women: a pilot double-blind, placebo-controlled randomized clinical trial

BACKGROUND AND AIMS

In some clinical studies men and women have been found to differ in their ability to quit smoking, perhaps as a result of progesterone. The primary aim of this study was to provide a preliminary test of whether progesterone (PRO), compared with placebo (PBO), was more effective for smoking cessation in men and women.

DESIGN

Pilot double-blind, placebo-controlled randomized clinical trial.

SETTING

Minneapolis/St Paul metro area, Minnesota, USA.

PARTICIPANTS

A total of 216 participants were randomized, including 113 men (18-60 years; PRO = 56, PBO = 57) and 103 women (18-50 years, pre-menopausal with self-reported regular menstrual cycles; PRO = 51, PBO = 52).

INTERVENTION

Participants were randomized (1 : 1 within sex group) to either PRO (200 mg twice daily) or PBO. Participants were assigned a quit date approximately 7 days after starting medication (luteal phase for women) and were followed for 12 weeks to assess relapse.

MEASUREMENTS

The primary outcome was self-reported 7-day point prevalence abstinence (PPA) at week 4. Secondary outcomes included 7-day PPA at weeks 8 and 12, prolonged abstinence, continuous abstinence, urine cotinine < 50 ng/ml, expired carbon monoxide ≤ 5 parts per million (p.p.m.) and days to relapse.

FINDINGS

There was a significant difference in 7-day PPA at week 4 among women [PRO: 18 (35.3%) versus PBO: 9 (17.3%), odds ratio (OR) = 2.61, 95% confidence interval (CI) = 1.04, 6.54, P = 0.041], but not among men [PRO: 13 (23.2%) versus PBO: 12 (21.1%), 1.13 (0.47, 2.76), P = 0.782]. There was some evidence that PRO delayed relapse in women (days to relapse; PRO: 20.5 ± 29.6 versus PBO: 14.3 ± 26.8, P = 0.03) but not in men (PRO: 13.4 ± 25.9 versus PBO: 13.3 ± 23.8, P = 0.69).

CONCLUSIONS

Oral micronized progesterone may aid smoking cessation in women.

Variability in nicotine conditioned place preference and stress-induced reinstatement in mice: Effects of sex, initial chamber preference, and guanfacine

Relapse to smoking occurs at higher rates in women compared with men, especially when triggered by stress. Studies suggest that sex-specific interactions between nicotine reward and stress contribute to these sex differences. Accordingly, novel treatment options targeting stress pathways, such as guanfacine, an α2-adrenergic receptor agonist, may provide sex-sensitive therapeutic effects. Preclinical studies are critical for elucidating neurobiological mechanisms of stress-induced relapse and potential therapies, but rodent models of nicotine addiction are often hindered by large behavioral variability. In this study, we used nicotine conditioned place preference to investigate stress-induced reinstatement of nicotine preference in male and female mice, and the effects of guanfacine on this behavior. Our results showed that overall, nicotine induced significant place preference acquisition and swim stress-induced reinstatement in both male and female mice, but with different nicotine dose-response patterns. In addition, we explored the variability in nicotine-dependent behaviors with median split analyses and found that initial chamber preference in each sex differentially accounted for variability in stress-induced reinstatement. In groups that showed significant stress-induced reinstatement, pretreatment with guanfacine attenuated this behavior. Finally, we evaluated neuronal activation by Arc immunoreactivity in the infralimbic cortex, prelimbic cortex, anterior insula, basolateral amygdala, lateral central amygdala and nucleus accumbens core and shell. Guanfacine induced sex-dependent changes in Arc immunoreactivity in the infralimbic cortex and anterior insula. This study demonstrates sex-dependent relationships between initial chamber preference and stress-induced reinstatement of nicotine conditioned place preference, and the effects of guanfacine on both behavior and neurobiological mechanisms.

Economic demand analysis of within-session dose-reduction during nicotine self-administration

BACKGROUND

This study determined if a within-session dose-reduction design sufficiently captures elasticity of demand for nicotine in male and female rats using environmental enrichment to manipulate demand elasticity.

METHODS

Male and female Sprague-Dawley rats were trained to self-administer nicotine (60 μg/kg/infusion). In Experiment 1, rats began daily dose-reduction for nine sessions following acquisition. Rats then underwent a minimum of five within-session dose-reduction sessions where each dose was available for 10 min. In Experiment 2, rats were reared in isolated, social, or enriched housing followed by acquisition of nicotine self-administration. Rats then underwent within-session dose-reduction. Housing environments were then switched, followed by additional testing sessions. Consumption was calculated for each dose and exponential demand curves were fit.

RESULTS

No sex differences in acquisition of nicotine self-administration were detected for either experiment. In experiment 1, demand intensity (Q₀; estimated intake if nicotine were freely available), was higher with between- compared to within-session dose-reduction, although elasticity of demand (α; rate of decline in nicotine intake as a function of increasing unit price), was lower. In Experiment 2, animals reared in enrichment had fewer infusions during acquisition compared to animals in isolation. Enriched males had reduced demand intensity compared to both isolated and social males, whereas isolated females had reduced intensity compared to enriched females.

CONCLUSIONS

The within-session dose-reduction procedure for nicotine self-administration replicated effects of environmental enrichment on consumption behaviors. Additionally, this procedure captured differences in nicotine demand due to sex, laying important groundwork for future translational research on mechanisms of nicotine dependence.

Association of exercise with smoking-related symptomatology, smoking behavior and impulsivity in men and women

INTRODUCTION

Despite extensive efforts to develop effective smoking cessation interventions, 70-85% of American cigarette smokers who quit relapse within one year. Exercise has shown promise as an intervention; however, many results have been equivocal. This study explored how exercise is associated with smoking-related symptomatology, smoking behavior and impulsivity in male and female smokers.

METHODS

Participants were recruited throughout the United States using the on-line crowdsourcing platform, Amazon's Mechanical Turk. They completed a survey with self-report measures assessing exercise, smoking-related symptomatology, smoking behavior and impulsivity. Differences between men and women were tested using t- and chi-square tests. Regression analyses tested for associations between exercise and smoking-related symptomatology, smoking behavior and impulsivity.

RESULTS

Participants (N = 604) were, on average, 32 (SD = 6.2) years old, mostly Caucasian, with at least some college education and approximately half were women. Women exercised slightly less than men and had more negative affect, craving, physical symptoms and withdrawal. Women smoked more cigarettes per day, had greater nicotine dependency and more years of smoking. Positive affect was positively associated with exercise for both men and women; however, this association was significantly stronger in women. Negative affect and withdrawal were inversely associated with exercise for women only. Impulsivity was inversely associated with exercise for both men and women.

CONCLUSION

Exercise was significantly associated with several smoking-related symptomatology, smoking behavior and impulsivity variables for both men and women, suggesting that exercise may be a useful intervention for smoking cessation. Future prospective research should determine how exercise directly impacts smoking cessation.

Longitudinal Associations of Local Cigarette Prices and Smoking Bans with Smoking Behavior in the Multi-Ethnic Study of Atherosclerosis

BACKGROUND

Few studies have examined associations of geographically proximal cigarette prices with within-person changes in smoking outcomes or assessed interactions between cigarette prices and smoking bans.

METHODS

We linked neighborhood cigarette prices (inflation-adjusted) at chain supermarkets and drug stores and bar/restaurant smoking ban policies to cohort participants (632 smokers from the Multi-Ethnic Study of Atherosclerosis, 2001-2012, baseline mean age 58 years) using geocoded retailer and participant addresses. We used fixed-effects models to investigate associations of within-person changes in price and ban exposures with within-person changes in five smoking outcomes: current smoking, heavy (≥10 cigarettes) smoking, cessation, relapse, and intensity (average number of cigarettes smoked per day, natural log transformed). We assessed intensity associations among all smokers, and heavy (≥10 cigarettes per day) and light (<10) baseline smokers. Finally, we tested interactions between cigarette price and bans.

RESULTS

A $1 increase in price was associated with a 3% reduction in risk of current smoking (adjusted risk ratio [aRR]: 0.97; 95% confidence interval [CI] = 0.93, 1.0), a 7% reduction in risk of heavy smoking (aRR: 0.93; CI = 0.87, 0.99), a 20% increase in risk of smoking cessation (aRR: 1.2; CI = 0.99, 1.4), and a 35% reduction in the average number of cigarettes smoked per day by heavy baseline smokers (ratio of geometric means: 0.65; CI = 0.45, 0.93). We found no association between smoking bans and outcomes, and no evidence that price effects were modified by the presence of bans.

CONCLUSIONS

Results underscore the importance of local prices, but not hospitality smoking bans, in influencing older adults' smoking behaviors.

The Association Between Low 50 g Glucose Challenge Test Values and Adverse Pregnancy Outcomes

BACKGROUND

The implications of low values on the 50 g glucose challenge test (GCT) in pregnancy are not clearly defined. Few studies have evaluated the influence of maternal low GCT values on obstetrical outcomes. This study aimed to compare pregnancy outcomes between women with low 50 g GCT values and those with normal values.

MATERIALS AND METHODS

Women undergoing gestational diabetes mellitus screening at 24-28 weeks of gestational age between January 2010 and December 2016 were retrospectively evaluated. Women with multifetal pregnancies, prepregnancy type I or II diabetes, GCT performed before 24 or after 28 weeks of gestational age, and women undergoing multiple GCTs in the same pregnancy were excluded. Low GCT values and normal GCT values were defined as ≤85 mg/dL and 86-130 mg/dL, respectively.

RESULTS

Of 3875 screened subjects, 519 (13.4%) women were included in the low GCT group and 3356 (86.6%) in the normal GCT group. Low GCT women had a significantly higher rate of small for gestational age (SGA) infants than normal GCT women (10.8% vs. 7.9%, p = 0.02). Cesarean section and postpartum hemorrhage (PPH) were less frequent in low GCT women than in normal women (32.6% vs. 42.8%, p < 0.01 and 0.2% vs. 1.2%, p = 0.03, respectively). Low GCT women had a 1.38-fold increased risk of bearing SGA infants (95% confidence intervals: 1.01-1.88, p = 0.04).

CONCLUSIONS

Rate of SGA infants was significantly higher and cesarean delivery and PPH rates were significantly lower in women with low GCT values. Low GCT values were independently associated with an increased risk of SGA.

One-Year Smoking Trajectories Among Established Adult Smokers With Low Baseline Motivation to Quit

INTRODUCTION

The majority of smokers do not intend to quit in the near term, making unmotivated smokers a key group to target in public health efforts. Although it is often assumed that continuing smokers will have stable rates of smoking over time, limited research has addressed this issue, particularly among smokers not seeking treatment. In the current study, the aims were to (1) characterize the trajectory of naturalistic smoking among unmotivated smokers and (2) examine relationships between naturalistic smoking trajectories and other smoking-related variables.

METHODS

The study sample comprised 579 control-group (ie, untreated) smokers within a parent clinical trial, who completed a total of nine assessments over 1 year.

RESULTS

Trajectory modeling identified four smoking trajectory groups: stable (72%), shallow decreasers (20%), steep decreasers (5%), and increasers (3%). Membership in the decreasing groups was associated with higher motivation to quit, greater history of quit attempts, and higher cigarettes per day. Females were more likely to be in the increasing versus stable group.

CONCLUSIONS

Findings provide needed information on stability and change in cigarette consumption over the course of 1 year among an untreated sample of smokers and identified baseline sociodemographic and smoking-related predictors of smoking trajectory group. Refining understanding of these groups is critical in updating population-based tobacco policy modeling efforts and informing cessation induction efforts that capitalize on naturalistic changes in smoking rate over time.

IMPLICATIONS

In the current study, we found that approximately 25% of smokers who endorsed low quit motivation at baseline reduced their cigarette consumption over the course of a year, while 3% increased their cigarette consumption and the majority of smokers (72%) maintained a stable pattern. Refining understanding of smoking trajectories is critical in updating population-based tobacco policy modeling efforts and informing cessation induction efforts that capitalize on naturalistic changes in smoking rate over time.

Changes in smoking status among a longitudinal cohort of gay, bisexual, and other men who have sex with men in Vancouver, Canada

BACKGROUND

Cigarette smoking is common among gay, bisexual, and other men who have sex with men (GBMSM) and most of the mortality gap between HIV-positive and HIV-negative individuals is attributable to smoking.

METHODS

We recruited sexually active HIV-positive and HIV-negative GBMSM age ≥16 years using respondent-driven sampling. Study visits occurred every six months for up to four years and included a computer-assisted self-interview and clinical assessment. We conducted bivariate analyses to compare factors associated with "never", "former", "daily", or "non-daily" smoking at baseline and longitudinal mixed effects models to examine factors associated with cessation and (re)initiation.

RESULTS

774 participants completed a baseline visit and 525 enrolled in the cohort and completed at least one follow-up visit. At baseline, the median age was 34 years and 31.5% were daily smokers. In follow-up (median=2.5years), 116 daily or non-daily smokers (41%) quit at least once and of these, 101 (87%) remained former smokers at their last visit. Smoking cessation was positively associated with incomes ≥$60,000 and self-reported excellent health. Alcohol use, ecstasy use, and having a partner who smokes were associated with decreased odds of cessation. Substance use (cannabis, GHB, and crystal methamphetamine) and having a partner who smokes were positively associated with increasing to/resuming daily smoking. HIV-positive GBMSM were more likely to smoke but not more likely to quit.

CONCLUSIONS

Targeted, culturally relevant smoking cessation resources are needed, especially for HIV-positive GBMSM. Engaging couples in cessation interventions may be useful.

Estimating the effect of differing assumptions on the population health impact of introducing a Reduced Risk Tobacco Product in the USA

We use Population Health Impact Modelling to assess effects on tobacco prevalence and mortality of introducing a Reduced Risk Tobacco Product (RRP). Simulated samples start in 1990 with a US-representative smoking prevalence. Individual tobacco histories are updated annually until 2010 using estimated probabilities of switching between never/current/former smoking where the RRP is not introduced, with current users subdivided into cigarette/RRP/dual users where it is. RRP-related mortality reductions from lung cancer, IHD, stroke and COPD are derived from the histories and the assumed relative risks of the RRP. A basic analysis assumes a hypothetical RRP reduces effective dose 80% in users and 40% in dual users, with an uptake rate generating ∼10% RRP and ∼6% dual users among current users after 10 years. Sensitivity study changes in tobacco prevalence and mortality from varying effective doses, current smoking risks, quitting half-lives and rates of initiation, switching, re-initiation and cessation. They also study extreme situations (e.g. everyone using RRP), and investigate assumptions which might eliminate the RRP-related mortality reduction. The mortality reduction is proportional to the dose reduction, increasing rapidly with time of follow-up. Plausible increases in re-initiation or dual users' consumption, or decreased quitting by smokers would not eliminate the drop.

Neighborhood social environment as risk factors to health behavior among African Americans: The Jackson Heart Study

BACKGROUND

Few studies have focused on the impact of neighborhood social environment on changes in smoking and alcohol use over time among African Americans.

METHOD

Jackson Heart Study participants were recruited from the Jackson, MS metropolitan area from 2000 to 2004. Neighborhood social environment was characterized using census-based neighborhood socio-economic status (NSES) and survey-derived perceptions of neighborhood social cohesion, disorder, and violence. Multinomial logistic regression was used to estimate the associations of neighborhood social environment with prevalence of smoking and alcohol use and with changes in these behaviors over time adjusted for individual sociodemographic characteristics.

RESULTS

Participants (N=3166) resided in 108 census tracts. All neighborhood social environment variables were consistently associated with prevalence of current smoking at baseline (11%) and with persistence of smoking over a median of 8-years follow-up (8%). The odds of being a consistent smoker relative to never smoking was about 30% higher per 1SD higher neighborhood violence (aOR: 1.30, 95% CI: 1.16-1.46) and disorder (aOR: 1.26, 95% CI: 1.08 - 1.47) and at least 16% lower per 1SD higher in neighborhood social cohesion (aOR: 0.84, 95% CI: 0.74-0.95) and NSES (aOR: 0.79, 95% CI: 0.67-0.95). Heavy alcohol use at baseline (17%) and consistent heavy use over the study period (8%) were negatively associated with higher NSES (aOR: 0.85, 95% CI: 0.73-0.99 per 1SD increase in NSES).

CONCLUSION

Favorable neighborhood social environments may reduce unhealthy behaviors among African Americans.

Sex Differences in Tobacco Use Among Persons Living With HIV/AIDS: A Systematic Review and Meta-Analysis

BACKGROUND

Persons living with HIV/AIDS (PLWH) smoke at higher rates than other adults and experience HIV-related and non-HIV-related adverse smoking consequences. This study conducted a systematic review to synthesize current knowledge about sex differences in smoking behaviors among PLWH.

METHODS

Over 3000 abstracts from MEDLINE were reviewed and 79 publications met all the review inclusion criteria (ie, reported data on smoking behaviors for PLWH by sex). Sufficient data were available to conduct a meta-analysis for one smoking variable: current smoking prevalence.

RESULTS

Across studies (n = 51), the meta-analytic prevalence of current smoking among female PLWH was 36.3% (95% confidence interval [CI]: 28.0% to 45.4%) and male PLWH was 50.3% (95% CI: 44.4% to 56.2%; meta-analytic odds ratio = 1.78, 95% CI: 1.29 to 2.45). When analyses were repeated just on the US studies (n = 23), the prevalence of current smoking was not significantly different for female PLWH (55.1%, 95% CI: 47.6% to 62.5%) compared with male PLWH (55.5%, 95% CI: 48.2% to 62.5%; meta-analytic odds ratio = 1.04, 95% CI: 0.86 to 1.26). Few studies reported data by sex for other smoking variables (eg, quit attempts, noncigarette tobacco product use) and results for many variables were mixed.

DISCUSSION

Unlike the general US population, there was no difference in smoking prevalence for female versus male PLWH (both >50%) indicating that HIV infection status was associated with a greater relative increase in smoking for women than men. More research is needed in all areas of smoking behavior of PLWH to understand similarities and differences by sex to provide the best interventions to reduce the high smoking prevalence for all sexes.

Changes in cigarette smoking initiation, cessation, and relapse among U.S. adults: a comparison of two longitudinal samples

BACKGROUND

The tobacco epidemic in the U.S. has matured in the past decade. However, due to rapidly changing social policy and commercial environments, tailored prevention and interventions are needed to support further reduction in smoking.

METHODS

Using Tobacco Use Supplement to the Current Population Survey (TUS-CPS) 2002-2003 and 2010-2011 longitudinal cohorts, five smoking states are defined including daily-heavy, daily-light, non-daily, former and non-smoker. We quantified the changes between smoking states for the two longitudinal cohorts, and used a series of multivariable logistic regression models to examine the association of socio-demographic attributes and initial smoking states on smoking initiation, cessation, and relapse between waves within each cohort.

RESULTS

The prevalence of adult heavy smoking decreased from 9.9% (95% CI: 9.6%, 10.2%) in 2002 to 7.1% (95% CI: 6.9%, 7.4%) in 2010. Non-daily smokers were less likely to quit in the 2010-2011 cohort than the 2002-2003 cohort (37.0% vs. 44.9%). Gender, age group, smoker type, race and marital status exhibit similar patterns in terms of their association to the odds of initiation, cessation and relapse between the two cohorts, while education groups showed some inconsistent results between the two cohorts regarding the odds of cessation.

CONCLUSIONS

Transitions between smoking states are complex and increasingly unstable, requiring a holistic, population-based perspective to understand the stocks and flows that ultimately dictate the public health impact of cigarette smoking behavior. This knowledge helps to identify groups in need of increased tobacco control prevention and intervention efforts.

Cross-sectional and longitudinal associations of neighbourhood social environment and smoking behaviour: the multiethnic study of atherosclerosis

BACKGROUND

Social features of neighbourhood environments may influence smoking by creating a stressful environment or by buffering stress through social cohesion. However, the association of the overall neighbourhood social environment (NSE) with smoking, and the association of specific neighbourhood social factors with change in smoking behaviour over time, has rarely been examined.

METHODS

This study included 5856 adults aged 45-84 years from the Multi-Ethnic Study of Atherosclerosis (2000-2012, average follow-up: 7.8 years). Outcomes included current smoking status and smoking intensity (average number of cigarettes smoked per day among baseline smokers). NSE was assessed as a composite score composed of aesthetic quality, safety and social cohesion scales (derived from neighbourhood surveys). Generalised linear mixed models evaluated the association of baseline NSE (composite score and individual scales) with current smoking (modified Poisson models) and smoking intensity (negative binomial models) cross-sectionally and longitudinally.

RESULTS

Each SD increase in baseline NSE composite score was associated with 13% lower prevalence of smoking at baseline (adjusted prevalence ratio (aPR) 0.87 (95% CI 0.78 to 0.98). Neighbourhood safety and aesthetic quality were similarly associated with lower smoking prevalence (aPR 0.87 (0.78 to 0.97) and aPR 0.87 (0.77 to 0.99), respectively) but the association with social cohesion was weaker or null. No significant associations were observed for smoking intensity among baseline smokers. Baseline NSE was not associated with changes in smoking risk or intensity over time.

CONCLUSIONS

Results suggest that neighbourhood social context influences whether older adults smoke, but does not promote smoking cessation or reduction over time.

Learning and generalization from reward and punishment in opioid addiction

This study adapts a widely-used acquired equivalence paradigm to investigate how opioid-addicted individuals learn from positive and negative feedback, and how they generalize this learning. The opioid-addicted group consisted of 33 participants with a history of heroin dependency currently in a methadone maintenance program; the control group consisted of 32 healthy participants without a history of drug addiction. All participants performed a novel variant of the acquired equivalence task, where they learned to map some stimuli to correct outcomes in order to obtain reward, and to map other stimuli to correct outcomes in order to avoid punishment; some stimuli were implicitly "equivalent" in the sense of being paired with the same outcome. On the initial training phase, both groups performed similarly on learning to obtain reward, but as memory load grew, the control group outperformed the addicted group on learning to avoid punishment. On a subsequent testing phase, the addicted and control groups performed similarly on retention trials involving previously-trained stimulus-outcome pairs, as well as on generalization trials to assess acquired equivalence. Since prior work with acquired equivalence tasks has associated stimulus-outcome learning with the nigrostriatal dopamine system, and generalization with the hippocampal region, the current results are consistent with basal ganglia dysfunction in the opioid-addicted patients. Further, a selective deficit in learning from punishment could contribute to processes by which addicted individuals continue to pursue drug use even at the cost of negative consequences such as loss of income and the opportunity to engage in other life activities.

Depression motivates quit attempts but predicts relapse: differential findings for gender from the International Tobacco Control Study

AIMS

To determine whether signs of current depression predict attempts to quit smoking, and short-term abstinence among those who try, and to test moderating effects of gender and cessation support (pharmacological and behavioural).

DESIGN

Prospective cohort with approximately annual waves. Among smokers at one wave we assessed outcomes at the next wave using mixed-effects logistic regressions.

SETTING

Waves 5-8 of the Four Country International Tobacco Control Study: a quasi-experimental cohort study of smokers from Canada, USA, UK and Australia.

PARTICIPANTS

A total of 6811 tobacco smokers who participated in telephone surveys.

MEASUREMENTS

Three-level depression index: (1) neither low positive affect (LPA) nor negative affect (NA) in the last 4 weeks; (2) LPA and/or NA but not diagnosed with depression in the last 12 months; and (3) diagnosed with depression. Outcomes were quit attempts and 1-month abstinence among attempters.

FINDINGS

Depression positively predicted quit attempts, but not after controlling for quitting history and motivational variables. Controlling for all covariates, depression consistently negatively predicted abstinence. Cessation support did not moderate this effect. There was a significant interaction with gender for quit attempts (P = 0.018) and abstinence (P = 0.049) after controlling for demographics, but not after all covariates. Depression did not predict abstinence among men. Among women, depressive symptoms [odds ratio (OR) = 0.63, 95% confidence interval (CI) = 0.49-0.81] and diagnosis (OR = 0.46, 95% CI = 0.34-0.63) negatively predicted abstinence.

CONCLUSIONS

Smokers with depressive symptoms or diagnosis make more quit attempts than their non-depressed counterparts, which may be explained by higher motivation to quit, but they are also more likely to relapse in the first month. These findings are stronger in women than men.

Sex Differences in Varenicline Efficacy for Smoking Cessation: A Meta-Analysis

INTRODUCTION

Women have lower rates of quitting than men with both bupropion and nicotine replacement. It is unknown whether varenicline demonstrates differential efficacy for men and women. The purpose of this study was to conduct the first comprehensive meta-analysis of clinical trial data examining sex differences in the efficacy of varenicline for smoking cessation.

METHODS

Searching MEDLINE, EMBASE, and PsychINFO, 17 of 43 clinical trials of varenicline for smoking cessation published through December 31, 2014 were low-bias randomized double-blind placebo-controlled trials. Data (n = 6710 smokers, 34% female, n = 16 studies, 96% of available data) was analyzed with Metafor program in R. Outcome endpoints were 7-day point-prevalence (PP) and continuous-abstinence (CA) at week 12 (end of treatment), week 24 (6-month follow-up), and week 52 (12-month follow-up).

RESULTS

Using placebo, women were less likely than men to quit (PP-12, CA-24; P < .05 for sex). Using varenicline, similar rates of abstinence for men and women were demonstrated for all six outcomes (eg, PP-12 abstinence rates were 53% in both women and men). Varenicline versus placebo outcomes demonstrated that varenicline was more effective for women for short and intermediate outcomes (PP-12, CA-12, CA-24; P < .05 sex × medication interaction). For end-of-treatment PP, varenicline was 46% more effective for women. For continuous abstinence, varenicline was 34% (CA-12) and 31% (CA-24) more effective for women.

CONCLUSIONS

Unlike other smoking cessation medications, varenicline demonstrated greater efficacy among women smokers for short and immediate-term outcomes and equal efficacy for 1-year outcomes. Varenicline may be particularly useful for reducing the sex disparity typically seen in rates of smoking cessation.

IMPLICATIONS

Varenicline is currently the most effective FDA-approved smoking cessation medication and this is the first demonstration that women compared with men have a preferred therapeutic response for a smoking cessation medication when considering short-term outcomes. Importantly, this is also the first demonstration that women have similar rates of quitting to men when considering longer-term, 1-year outcomes.

Barriers to Quitting Smoking Among Substance Dependent Patients Predict Smoking Cessation Treatment Outcome

For smokers with substance use disorders (SUD), perceived barriers to quitting smoking include concerns unique to effects on sobriety as well as usual concerns. We expanded our Barriers to Quitting Smoking in Substance Abuse Treatment (BQS-SAT) scale, added importance ratings, validated it, and then used the importance scores to predict smoking treatment response in smokers with substance use disorders (SUD) undergoing smoking treatment in residential treatment programs in two studies (n=184 and 340). Both components (general barriers, weight concerns) were replicated with excellent internal consistency reliability. Construct validity was supported by significant correlations with pretreatment nicotine dependence, smoking variables, smoking self-efficacy, and expected effects of smoking. General barriers significantly predicted 1-month smoking abstinence, frequency and heaviness, and 3-month smoking frequency; weight concerns predicted 1-month smoking frequency. Implications involve addressing barriers with corrective information in smoking treatment for smokers with SUD.

The National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) Waves 1 and 2: review and summary of findings

PURPOSE

The NESARC, a "third-generation" psychiatric epidemiologic survey that integrated detailed measures of alcohol and drug use and problems has been the data source for over >850 publications. A comprehensive review of NESARC findings and their implications is lacking.

METHOD

NESARC was a survey of 43,093 participants that covered alcohol, drug and psychiatric disorders, risk factors, and consequences. Wave 1 of the NESARC was conducted in 2001-2002. Three years later, Wave 2 follow-up re-interviews were conducted with 34,653 of the original participants. Scopus and Pubmed were used to search for NESARC papers, which were sorted into topic areas and summarized.

RESULT

The most common disorders were alcohol and posttraumatic stress disorders, and major depression. Females had more internalizing disorders and males had more externalizing disorders, although the preponderance of males with alcohol disorders (the "gender gap") was less pronounced than it was in previous decades. A race/ethnic "paradox" (lower risk among disadvantaged minorities than whites) remains unexplained. Younger participants had higher risk for substance and personality disorders, but not unipolar depressive or anxiety disorders. Psychiatric comorbidity was extensive and often formed latent trans-diagnostic domains. Since 1991-1992, risk for marijuana and prescription drug disorders increased, while smoking decreased, although smoking decreases were less pronounced among those with comorbidity. A nexus of comorbidity, social support, and stress predicted transitions in diagnostic status between Waves 1 and 2. Childhood maltreatment predicted psychopathology. Alcohol and drug use disorders were seldom treated; attitudinal barriers (little perceived need, perceived alcoholism stigma, pessimism about efficacy) were more important in predicting non-treatment than financial barriers.

CONCLUSIONS

Understanding comorbidity and the effects of early stressors will require research incorporating biologic components, e.g., genetic variants and brain imaging. The lack of treatment for alcohol and drug disorders, predicted by attitudinal rather than financial variables, suggests an urgent need for public and professional education to reduce the stigma associated with these disorders and increase knowledge of treatment options.

Twenty years and still counting: including women as participants and studying sex and gender in biomedical research

BACKGROUND

This paper chronicles attempts in the United States over the past 20 years to fully represent women in clinical trials and ensure the study of sex and gender in biomedical research. We maintain that productive science with the aim of serving the public health requires examining the influence of sex and gender on health outcomes.

DISCUSSION

This section provides a historical perspective on the changes in recommendations and requirements of both the National Institutes of Health - the world's largest single funder of biomedical research - and the U.S. Food and Drug Administration - the world's most influential regulator of drugs and medical devices - for the acceptable conduct of research as it relates to sex and gender. We also cite all reports by the U.S. Institute of Medicine and the U.S. Congress' General Accountability Office issued from 1990 to the present on the inclusion of sex and gender in research, and selected high-impact published studies that illustrate and document the paucity of, yet the need for, inclusion of females and consideration of sex and gender in research across an array of biomedical disciplines. The key message of this paper is that it has been 20 years since the first requirements to include women as well as men in clinical trials and analyze results by sex were mandated by a U.S. federal law, yet not nearly enough progress has been made. Recent signs of potential change in both policy and practice of scientific inquiry suggest much more progress may be within reach. However, awaiting a cultural shift to allow the study of sex and gender to be embraced is not seen as an effective strategy for change. Rather, specific instrumental recommendations are offered for how to include the study of sex and gender in research so as to increase our understanding and promotion of health for the benefit of all.

Systematic and meta-analytic review of research examining the impact of menstrual cycle phase and ovarian hormones on smoking and cessation

INTRODUCTION

To determine the effect of ovarian hormones on smoking, we conducted a systematic review of menstrual cycle effects on smoking (i.e., ad lib smoking, smoking topography, and subjective effects) and cessation-related behaviors (i.e., cessation, withdrawal, tonic craving, and cue-induced craving).

METHODS

Thirty-six papers were identified on MEDLINE that included a menstrual-related search term (e.g., menstrual cycle, ovarian hormones), a smoking-related search term (e.g., smoking, nicotine), and met all inclusion criteria. Thirty-two studies examined menstrual phase, 1 study measured hormone levels, and 3 studies administered progesterone.

RESULTS

Sufficient data were available to conduct meta-analyses for only 2 of the 7 variables: withdrawal and tonic craving. Women reported greater withdrawal during the luteal phase than during the follicular phase, and there was a nonsignificant trend for greater tonic craving in the luteal phase. Progesterone administration was associated with decreased positive and increased negative subjective effects of nicotine. Studies of menstrual phase effects on the other outcome variables were either small in number or yielded mixed outcomes.

CONCLUSIONS

The impact of menstrual cycle phase on smoking behavior and cessation is complicated, and insufficient research is available upon which to conduct meta-analyses on most smoking outcomes. Future progress will require collecting ovarian hormone levels to more precisely quantify the impact of dynamic changes in hormone levels through the cycle on smoking behavior. Clarifying the relationship between hormones and smoking-particularly related to quitting, relapse, and medication response-could determine the best type and timing of interventions to improve quit rates for women.

Targeting the noradrenergic system for gender-sensitive medication development for tobacco dependence

INTRODUCTION

Tobacco use remains the leading cause of morbidity and mortality for both women and men in the United States, and women often experience poorer smoking cessation outcomes than men. Preliminary evidence suggests there are sex differences in medication effectiveness for smoking cessation. However, current medications do not take into account gender-sensitive treatment development and efficacy, underscoring the importance of this underdeveloped area of research.

METHODS

We reviewed preclinical and clinical evidence for gender differences in the inability to quit smoking by examining (a) the effect of increased negative affect and stress reactivity on smoking outcomes in women and (b) smoking for nicotine reinforcement in men. We also reviewed the current literature targeting the noradrenergic system as a novel gender-sensitive treatment strategy for tobacco dependence.

RESULTS

We hypothesize that noradrenergic agents that normalize noradrenergic activity may differentially attenuate stress reactivity in women and nicotine-related reinforcement in men, indicating that targeting the noradrenergic system for smoking cessation may be effective for both genders, with benefits operating through sex-specific mechanisms.

CONCLUSIONS

Converging lines of preclinical and clinical evidence suggest that gender-sensitive approaches to medication development for smoking cessation are a critical next step for addressing low quit rates and exacerbated health risks among women. Evidence reviewed indicates that smoking activates different brain systems modulated by noradrenergic activity in women versus men, and noradrenergic compounds may preferentially target these gender-sensitive systems.