Smoking Cessation in Mice Does Not Switch off Persistent Lung Inflammation and Does Not Restore the Expression of HDAC2 and SIRT1

Once COPD is established, pulmonary lesions can only progress and smoking cessation by itself is not sufficient to switch off persistent lung inflammation. Similarly, in former-smoker mice, neutrophil inflammation persists and lung lesions undergo progressive deterioration. The molecular mechanisms underlying disease progression and the inefficiency of smoking cessation in quenching neutrophilic inflammation were studied in male C57 Bl/6 mice after 6 months of rest from smoking cessation. As compared with the mice that continued to smoke, the former-smoker mice showed reduced expression of histone deacetylases HDAC2 and SIRT1 and marked expression of p-p38 MAPK and p-Ser10. All these factors are involved in corticosteroid insensitivity and in perpetuating inflammation. Former-smoker mice do show persistent lung neutrophilic influx and a high number of macrophages which account for the intense staining in the alveolar structures of neutrophil elastase and MMP-9 (capable of destroying lung scaffolding) and 8-OHdG (marker of oxidative stress). “Alarmins” released from necrotic cells together with these factors can sustain and perpetuate inflammation after smoking cessation. Several factors and mechanisms all together are involved in sustaining and perpetuating inflammation in former-smoker mice. This study suggests that a better control of COPD in humans may be achieved by precise targeting of the various molecular mechanisms associated with different phenotypes of disease by using a cocktail of drug active toward specific molecules.

Efficacy of non-invasive brain stimulation interventions in reducing smoking frequency in patients with nicotine dependence: a systematic review and network meta-analysis of randomized controlled trials

BACKGROUND AND AIMS

Nicotine is a highly addictive substance in tobacco products that dysregulates several neurotransmitters in the brain and impairs executive function. Non-invasive brain stimulation (NIBS) methods such as repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) are promising treatments for nicotine dependence. We investigated the efficacy and acceptability of NIBS in managing smoking cessation through a systematic review and network meta-analysis (NMA).

METHODS

We conducted a systematic review to identify randomized controlled trials (RCTs) that investigated the efficacy of NIBS for smoking cessation. All pairwise meta-analyses and NMA procedures were conducted using random-effects and frequentist models. The co-primary outcomes were (1) the change in number of cigarettes smoked per day (change in frequency of smoking) in patients with nicotine dependence after NIBS and (2) acceptability (the dropout rate). The effect sizes for co-primary outcomes of change in frequency of smoking and acceptability were assessed according to standardized mean difference (SMD) and odds ratio, respectively.

RESULTS

Twelve RCTs with 710 participants (mean age: 44.2 years, 31.2% female) were included. Compared with the sham control, 10-Hz rTMS over the left dorsolateral prefrontal cortex (DLPFC) was associated with the largest changes in smoking frequency [SMD = -1.22, 95% confidence interval (95% CI) = -1.77 to -0.66]. The 2-mA bifrontal tDCS (SMD = -0.97, 95% CI = -1.32 to -0.62) and 10-Hz deep rTMS over the bilateral DLPFC with cue provocation (SMD = -0.77, 95% CI = -1.20 to -0.34) were associated with a significantly larger decrease in smoking frequency versus the sham. None of the investigated NIBSs was associated with dropout rates significantly different from those of the sham control groups.

CONCLUSION

Prefrontal non-invasive brain stimulation interventions appear to reduce the number of cigarettes smoked with good acceptability.

The effect of preoperative smoking and smoke cessation on wound healing and infection in post-surgery subjects: A meta-analysis

A meta-analysis was performed to evaluate the preoperative smoking and smoke cessation on wound healing and infection in post-surgery subjects. A systematic literature search up to January 2022 incorporated 11 trials involving 218 567 subjects after post-surgery at the beginning of the study; 176 670 were smoke cessation or non-smokers, and 41 897 were smokers. Statistical tools like the dichotomous method were used within a random or fixed-influence model to establish the odds ratio (OR) with 95% confidence intervals (CIs) to evaluate the influence of preoperative smoking and smoke cessation on wound healing and infection in post-surgery subjects. Smoke cessation or non-smokers had significantly lower postoperative wound healing problems (OR, 0.59; 95% confidence interval, 0.43-0.82, P < .001), and surgical site wound infection (OR, 0.74; 95% CI, 0.63-0.87, P < .001) compared with smokers in post-surgery subjects. Smoke cessation or non-smokers had significantly lower postoperative wound healing problems, and surgical site wound infection compared with smokers in post-surgery subjects. Furthermore, evidence is needed to confirm the outcomes.

Factors Correlated with Smoking Cessation Success in Older Adults: A Retrospective Cohort Study in Taiwan

Smoking cessation in the elderly is very important. This study aims to explore the success rate of smoking cessation in the elderly and the factors that predict the success of smoking cessation. We collected data from smokers ≥60 years who visited a medical center in Taiwan during 2017. All patients were prescribed either varenicline or nicotine replacement therapy (NRT) for smoking cessation. The participants were asked about their smoking status after treatment. In total, 129 participants were enrolled. The three- or six-month point abstinence rate was 48.1%. No significant difference was found among baseline characteristics (including age, gender, underlying diseases, smoking duration, daily consumption amount of cigarette, carbon monoxide concentration, Fagerström test for nicotine dependence scores, and treatment method) between quitters and non-quitters, except for the type of medication used. The proportion of quitters using varenicline was significantly higher than that of non-quitters. Multivariate regression analyses showed that the patients who received varenicline were 3.22 times more likely to quit smoking than those who received NRT. Therefore, we suggest that varenicline use may help in smoking cessation in older adults, compared to NRT. Other baseline characteristics may not affect the success rate of smoking cessation in this population.

Effects of different pharmacologic smoking cessation treatments on body weight changes and success rates in patients with nicotine dependence: A network meta-analysis

Smoking cessation is a public health priority to reduce smoking-related morbidity and mortality. However, weight gain is a known primary reason for not trying to quit smoking. The aim of the current study was to investigate differences in weight gain associated with different pharmacological smoking cessation interventions. Randomized controlled trials (RCTs) that reported weight gain related to pharmacologic treatments for smoking cessation were analysed using network meta-analysis with a random effects model. Thirty-one RCTs with 5650 participants were included. Ten drugs and 22 regimens were identified. Nicotine patches plus fluoxetine, topiramate with/without nicotine patches, nicotine patches plus methylphenidate, nicotine spray/gum/lozenges, high-dose nicotine patches (42 mg/21 mg), naltrexone with/without nicotine patches, or bupropion with/without nicotine patches were associated with less weight gain than the placebo/control arm. Nicotine patches plus fluoxetine were associated with the least weight gain of all smoking cessation treatments. In addition, the nicotine patch plus topiramate and nicotine inhaler was associated with the best success rate and the least dropout rate, respectively. Overall, the nicotine patch 14 mg plus fluoxetine 40 mg, nicotine patch 14 mg plus fluoxetine 20 mg, and topiramate 200 mg would be the three best pharmacologic treatments based upon both weight gain effect and success rate.