Cecilia L. Bergeria

Addiction Potential of Cigarettes With Reduced Nicotine Content in Populations With Psychiatric Disorders and Other Vulnerabilities to Tobacco Addiction.

Importance A national policy is under consideration to reduce the nicotine content of cigarettes to lower nicotine addiction potential in the United States. Objective To examine how smokers with psychiatric disorders and other vulnerabilities to tobacco addiction respond to cigarettes with reduced nicotine content. Design, Setting, and Participants A multisite, double-blind, within-participant assessment of acute response to research cigarettes with nicotine content ranging from levels below a hypothesized addiction threshold to those representative of commercial cigarettes (0.4, 2.3, 5.2, and 15.8 mg/g of tobacco) at 3 academic sites included 169 daily smokers from the following 3 vulnerable populations: individuals with affective disorders (n = 56) or opioid dependence (n = 60) and socioeconomically disadvantaged women (n = 53). Data were collected from March 23, 2015, through April 25, 2016. Interventions After a brief smoking abstinence, participants were exposed to the cigarettes with varying nicotine doses across fourteen 2- to 4-hour outpatient sessions. Main Outcomes and Measures Addiction potential of the cigarettes was assessed using concurrent choice testing, the Cigarette Purchase Task (CPT), and validated measures of subjective effects, such as the Minnesota Nicotine Withdrawal Scale. Results Among the 169 daily smokers included in the analysis (120 women [71.0%] and 49 men [29.0%]; mean [SD] age, 35.6 [11.4] years), reducing the nicotine content of cigarettes decreased the relative reinforcing effects of smoking in all 3 populations. Across populations, the 0.4-mg/g dose was chosen significantly less than the 15.8-mg/g dose in concurrent choice testing (mean [SEM] 30% [0.04%] vs 70% [0.04%]; Cohen d = 0.40; P < .001) and generated lower demand in the CPT (&agr; = .027 [95% CI, 0.023-0.031] vs &agr; = .019 [95% CI, 0.016-0.022]; Cohen d = 1.17; P < .001). Preference for higher over lower nicotine content cigarettes could be reversed by increasing the response cost necessary to obtain the higher dose (mean [SEM], 61% [0.02%] vs 39% [0.02%]; Cohen d = 0.40; P < .001). All doses reduced Minnesota Nicotine Withdrawal Scale total scores (range of mean decreases, 0.10-0.50; Cohen d range, 0.21-1.05; P < .001 for all), although duration of withdrawal symptoms was greater at higher doses (&eegr;2 = 0.008; dose-by-time interaction, P = .002). Conclusions and Relevance Reducing the nicotine content of cigarettes may decrease their addiction potential in populations that are highly vulnerable to tobacco addiction. Smokers with psychiatric conditions and socioeconomic disadvantage are more addicted and less likely to quit and experience greater adverse health impacts. Policies to reduce these disparities are needed; reducing the nicotine content in cigarettes should be a policy focus.

Physical activity and cannabis cessation.

BACKGROUND AND OBJECTIVES Based on recent empirical and theoretical work suggesting that physical activity (PA) activates many of the same physiological systems as cannabis, the present study sought to investigate the impact of PA level (ie, low [including none] vs. moderate/high) on a cannabis cessation attempt during the first 7 days post-quit. METHODS The present study was a 2 time-point prospective study of 84 cannabis dependent military veterans (3 female) who responded to study flyers, within a Veterans Affairs Medical Center, seeking individuals interested in engaging in a self-guided cessation attempt. All study measures were self-report. RESULTS Though no baseline differences between those with low and those with moderate/high levels of physical activity were observed, results revealed that participants who reported low levels of physical activity, versus moderate/high levels, were significantly more likely to report a cannabis lapse during the week following a quit attempt, particularly within the first 4 days of the cessation period. Further, individuals with low levels of PA were also more likely to report greater mean cannabis use during the first 4 days of the cessation period. CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE Findings suggest that early interventions aimed at increasing physical activity may be useful among individuals with cannabis dependence who are engaged in a cessation attempt.

Surveying Lactation Professionals Regarding Marijuana Use and Breastfeeding

BACKGROUND Breastfeeding is associated with substantial benefits for both the child and mother. Most guidelines state that women who use illicit drugs should not breastfeed. Although this recommendation has traditionally included marijuana, this drugs changing legal status and the limited scientific research regarding marijuanas effect on breastfeeding and the nursing child may lead to varying recommendations made by lactation professionals to clients who use marijuana. Additionally, to our knowledge, there are no data estimating the prevalence of marijuana use among breastfeeding women, making it unclear how common it is. This study assessed recommendations around breastfeeding and marijuana use and estimated the prevalence of marijuana use among breastfeeding women. MATERIALS AND METHODS A convenience sample of lactation professionals who practice throughout New England and were attending the 2014 Vermont Lactation Consultant Association conference was offered the opportunity to complete a five-item survey. RESULTS Of 120 conference attendees, 74 completed the survey. Forty-four percent reported their recommendations around breastfeeding and marijuana use depended on factors like the severity of maternal use. Another 41% reported recommending continued breastfeeding because the benefits outweigh the harms. The remaining 15% reported recommending that a woman should stop breastfeeding if she cannot stop using marijuana. Survey completers estimated that 15% (1,203/7,843) of their breastfeeding clients in the past year used marijuana. CONCLUSIONS Lactation professionals vary widely in their recommendations to breastfeeding clients who use marijuana. The estimate of prevalence also suggests this is a relatively common issue. More research is needed to assess the generalizability of these findings.

Preventing relapse after incentivized choice treatment: A laboratory model☆

Two experiments with rats examined relapse of an operant behavior that occurred after the behavior was suppressed by reinforcing (incentivizing) an alternative behavior. In the first phase, a target response (R1) was reinforced. In a treatment phase, R1 was still reinforced, but a new response (R2) was introduced and associated with a larger reinforcer. As in human contingency management treatments, incentivizing R2 this way was effective at suppressing R1. However, when R2s reinforcement was discontinued, there was a robust and immediate relapse to R1. Experiment 1 found that the strength of R1 during relapse testing was not different from that seen in a no treatment control. Experiment 2 found that relapse could nevertheless be reduced by presenting reinforcers not contingent on responding during the test. Either the reinforcer for R1 or the reinforcer for R2 (which were qualitatively different types of food pellets) were effective. The experiments introduce a laboratory method for studying relapse and how to prevent it after contingency management treatments, and suggest at least one treatment that discourages relapse. The incentivized choice paradigm differs from other models of relapse of operant behavior (e.g., resurgence, renewal, reinstatement) in that it does not focus on the return of behaviors that are inhibited by extinction.

Comparing Smoking Topography and Subjective Measures of Usual Brand Cigarettes Between Pregnant and Non-Pregnant Smokers

Introduction Most pregnant smokers report abruptly reducing their cigarettes per day (CPD) by ~50% after learning of pregnancy and making further smaller reductions over the remainder of their pregnancy. Laboratory and naturalistic studies with non-pregnant smokers have found that these types of reductions often lead to changes in smoking topography (i.e., changes in smoking intensity to maintain a desired blood-nicotine level). If pregnant women smoke more intensely, they may expose themselves and their offspring to similar levels of toxicants despite reporting reductions in CPD. Methods Pregnant and non-pregnant female smokers (n = 20 and 89, respectively) participated. At the experimental session, after biochemical confirmation of acute abstinence, participants smoked one usual brand cigarette ad lib through a Borgwaldt CReSS Desktop Smoking Topography device. Carbon monoxide (CO) and measures of nicotine withdrawal, craving, and reinforcement derived from smoking were also collected. Results The two groups did not differ on demographic or smoking characteristics at screening, except nicotine metabolism rate, which as expected, was faster in pregnant smokers. Analyses suggest that none of the smoking topography parameters differed between pregnant and non-pregnant smokers, although pregnant smokers had a significantly smaller CO boost. Both groups reported similar levels of relief of withdrawal and craving after smoking, but other subjective effects suggest that pregnant smokers find smoking less reinforcing than non-pregnant smokers. Conclusions Pregnant smokers do not smoke cigarettes differently than non-pregnant women, but appear to find smoking comparatively less pleasurable. Implications This is the first study to assess smoking topography in pregnant women. Pregnant women appear to be at increased risk for smoking cigarettes with more intensity because of (1) their tendency to make significant abrupt reductions in the number of cigarettes they smoke each day after learning of pregnancy and (2) an increase in nicotine metabolism induced by pregnancy. Despite these changes, the present results suggest that pregnant women do not smoke cigarettes more intensely or in a way that causes more toxicant exposure, perhaps due to a reportedly less pleasurable smoking experience.

Response to reduced nicotine content cigarettes among smokers with chronic health conditions

Individuals with chronic health conditions persist in smoking despite the presence of smoking-related illness. The aim of this study was to examine whether chronic health conditions moderate response to reduced nicotine content cigarettes (0.4, 2.4, 5.2, 15.8 mg/g of tobacco). This is a secondary analysis of a controlled clinical laboratory study that examined the acute effects of cigarettes varying in nicotine content among individuals especially vulnerable to smoking and tobacco dependence. Participants in the present study were categorized as having 0, 1–2, or ≥3 smoking-related chronic health conditions (i.e., chronic condition severity, CCS). Repeated-measures analysis of variance was used to examine whether CCS moderated response to cigarettes across measures of addiction potential (i.e., concurrent choice testing between nicotine dose pairs, Cigarette Purchase Task (CPT) performance, positive subjective effects), tobacco withdrawal, cigarette craving, and smoking topography. No main effects of CCS or interactions of CCS and nicotine dose were observed for concurrent choice testing, positive subjective effects, tobacco withdrawal, or smoking topography. Main effects of CCS were noted on the CPT with greater CCS being associated with less persistent demand. There was an interaction of CCS and nicotine dose on Factor 1 of the Questionnaire on Smoking Urges with the effects of dose significant only among those with 1–2 chronic conditions. Overall, we see minimal evidence that chronic condition severity affects response to reduced nicotine content cigarettes. A policy that reduces the nicotine content of cigarettes to minimally addictive levels may benefit smokers already experiencing smoking-related chronic conditions.

Response to reduced nicotine content cigarettes among smokers differing in tobacco dependence severity

This study examines whether tobacco dependence severity moderates the acute effects of reducing nicotine content in cigarettes on the addiction potential of smoking, craving/withdrawal, or smoking topography. Participants (N = 169) were daily smokers with mild, moderate, or high tobacco-dependence severity using the Heaviness of Smoking Index. Following brief abstinence, participants smoked research cigarettes varying in nicotine content (0.4, 2.4, 5.2, 15.8 mg nicotine/g tobacco) in a within-subject design. Results were analyzed using repeated measures analysis of co-variance. No main effects of dependence severity or interactions with nicotine dose were noted in relative reinforcing effects in concurrent choice testing or subjective effects on the modified Cigarette Evaluation Questionnaire. Demand for smoking in the Cigarette Purchase Task was greater among more dependent smokers, but reducing nicotine content decreased demand independent of dependence severity. Dependence severity did not significantly alter response to reduced nicotine content cigarettes on the Minnesota Tobacco Withdrawal Scale nor Questionnaire of Smoking Urges-brief (QSU) Factor-2 scale; dependence severity and dose interacted significantly on the QSU-brief Factor-1 scale, with reductions dependent on dose among highly but not mildly or moderately dependent smokers. Dependence severity and dose interacted significantly on only one of six measures of smoking topography (i.e., maximum flow rate), which increased as dose increased among mildly and moderately but not highly dependent smokers. These results suggest that dependence severity has no moderating influence on the ability of reduced nicotine content cigarettes to lower the addiction potential of smoking, and minimal effects on relief from craving/withdrawal or smoking topography.