New medications for nicotine dependence treatment

Cardiovascular risks in smokers treated with nicotine replacement therapy: a historical cohort study

Background

Previous research suggests exposure to nicotine replacement therapy (NRT) may be associated with an increased risk of cardiovascular disease (CVD).

Methods

Using data from the United Kingdom’s Clinical Practice Research Datalink, this study aimed to evaluate CVD events and survival among individuals who attempted smoking cessation with the support of NRT compared with those aided by smoking cessation advice only. We studied CVD outcomes over 4 and 52 weeks in 50,214 smokers attempting to quit – 33,476 supported by smoking cessation advice and 16,738 with the support of NRT prescribed by their primary care physician. Patients were matched (2 smoking cessation advice patients:1 NRT patient) on demographic and clinical characteristics during a baseline year preceding their quit attempt. Cox proportional hazard regression, conditional negative binomial regression model, and conditional logistic regression were used to analyze data.

Results

Mean (standard deviation) population age was 47 (11.2) years; 51% were females. Time to first diagnosis of ischemic heart disease (IHD) among NRT and smoking cessation advice patients was similar within the first 4 weeks, but shorter for NRT patients over 52 weeks (hazard ratio [HR]: 1.35, 95% confidence interval [CI]: 1.03–1.77). A similar trend was observed for cerebrovascular disease (HR: 1.54, 95% CI: 1.08–2.19). NRT patients with a prior diagnosis of IHD or cerebrovascular disease had a higher rate of primary or secondary care consultations for IHD or cerebrovascular disease by 52 weeks (rate ratio: 1.50, 95% CI: 1.14–1.99). Patients prescribed NRT had a shorter survival time over 52 weeks, compared with those receiving advice only (HR: 1.39, 95% CI: 1.09–1.76).

Conclusion

Our findings suggest that treatment with NRT over 4 weeks does not appear to have an impact on cardiovascular risks. However, a longer follow-up period of 52 weeks resulted in an increase in cardiovascular events for patients prescribed NRT, compared with those receiving smoking cessation advice only.

The association among depressive symptoms, smoking status and antidepressant use in cardiac outpatients

Both depression and smoking are highly prevalent and related to poorer outcomes in cardiac patients. In this study, the authors examined the association between depressive symptoms and smoking status, described the frequency and type of antidepressant use, and prospectively tested the effects of antidepressant use in smokers on smoking status and psychosocial outcomes. Participants comprised 1,498 coronary artery disease (CAD) outpatients who completed a baseline survey which assessed depressive symptoms, current medications, and smoking status. A second survey was mailed 9 months later that assessed depressive symptoms, anxiety, insomnia and smoking status. Results showed that current and former-smokers had significantly greater depressive symptoms than non-smokers. Ten percent of patients were taking antidepressants, most frequently SSRIs, with significantly more smokers on antidepressants than former and non-smokers. At follow-up, smokers on antidepressants were less likely to have quit, had greater anxiety, depressive symptoms and insomnia than smokers not using antidepressants. This study demonstrated that smokers and quitters with CAD had greater depressive symptoms and use of antidepressants than non-smokers, but that the antidepressants utilized may not be optimizing outcomes.

Reversal of Triazolam Tolerance and Withdrawal-Induced Hyperlocomotor Activity and Anxiety by Bupropion in Mice

Chronic administration of triazolam (0.25 mg/kg/day, i.p.) on days 1-8 and its withdrawal produced an anxiogenic reaction in mice as assessed in the mirrored-chamber test. Daily administration of bupropion (2 or 5 mg/kg, i.p.) prior to triazolam for 8 days prevented withdrawal-induced anxiety in mice. Triazolam withdrawal also induced a significant increase in the locomotor activity of mice indicating an anxiogenic response. Daily administration of bupropion (2 or 5 mg/kg) prior to triazolam for 8 days also prevented withdrawal-induced increased locomotor activity. In conclusion, chronic administration of bupropion (2 and 5 mg/kg) exhibited a significant protection against triazolam withdrawal-induced anxiety and hyperlocomotor activity in mice. The result suggests the protective effect of bupropion in the management of triazolam withdrawal reactions.

Acute effects of self-paced walking on urges to smoke during temporary smoking abstinence

RATIONALE

Recent research highlights the need to extend our understanding of how exercise may aid smoking cessation, through exploration of different modes, intensity and duration of exercise.

OBJECTIVES

The purpose of the study was to examine the effects of a 1-mile self-paced walk on different measures of urges to smoke following temporary smoking abstinence.

METHODS

In a within-subject counterbalanced design, following 15 h of smoking abstinence, participants (N=15) exercised or sat passively on separate days. A single-item measure of strength of desire to smoke was administered during, immediately post, and at 10 and 20 min post-treatment. The two-factor Questionnaire for Smoking Urges, involving intention and desire to engage in smoking behaviour which is anticipated as pleasant, enjoyable and satisfying (desire-behave), and anticipation of relief from negative affect through smoking (desire-affect relief), was administered before and 20 min post-treatment.

RESULTS

A two-way repeated-measures MANOVA revealed a significant overall interaction effect for time by condition for strength of desire to smoke, and the two QSU scales. Two-way repeated-measures univariate ANOVAs revealed significant interaction effects for time by condition for each of the three urges to smoke measures. Planned contrasts revealed that exercise reduced cigarette cravings for up to 20 min after exercise, in comparison with the control condition. ANCOVAs revealed mixed support for independent effects of exercise on all measures of urges to smoke.

CONCLUSION

A self-paced walk, at a low intensity, lasting 15-20 min can have a rapid and measurable positive effect on both single and multi-item measures of urges to smoke, lasting at least 20 min, during temporary smoking abstinence.

Immunization to nicotine with a peptide-based vaccine composed of a conformationally biased agonist of C5a as a molecular adjuvant

This paper describes the synthesis of a nicotine hapten (Nic) that possesses a carboxyl sidearm functional group allowing for conjugation to a peptide via amide bond formation. Nic was attached to the N-terminal amino group of a 19-residue peptide composed of a conformationally biased agonist of human C5a (YSFKPMPLaR), which is used as a molecular adjuvant and a B cell epitope of human MUC1 glycoprotein (YKQGGFLGL) to yield a peptide-based nicotine vaccine, NicYKQGGFLGLYSFKPMPLaR. Rats immunized with this vaccine were significantly less sensitive to behavioral effects (a Pavlovian discrimination task) induced by their exposure to high concentrations of nicotine (0.4 mg/kg) relative to their non-vaccinated counterparts. The attenuation of these nicotine-induced behavioral effects emanated from the presence of nicotine-specific antibodies (Abs) that were present in the sera of vaccinated rats even after their repeated exposure to high concentrations of nicotine during the time required to perform the behavioral assays. These results suggest that immunization with NicYKQGGFLGLYSFKPMPLaR in the absence of adjuvant is an effective means of inducing a nicotine-specific Ab response, which is capable of attenuating nicotine-induced behavioral/psychoactive effects.