Purpose
The prevalence of light smoking has increased in North America; however, research on the effectiveness of current treatments in this sub-population of smokers is limited. We compared quit outcomes between light (1-10 cigarettes per day (CPD)) versus heavier smokers (>10 CPD) enrolled in a treatment program at their primary care clinic.
Methods
This secondary analysis analyzed 45,087 participants (light smokers (n=9,861); heavier smokers (n=35,226)) enrolled in a smoking cessation program between April 2016 and March 2020. The program offered cost-free nicotine replacement therapy (NRT) plus in-person counselling. Type, dose and duration of NRT treatment was personalized. Data were collected at baseline, and at 6-month following enrollment to assess 7-day point prevalence abstinence (PPA), the primary outcome variable of interest. Logistic regression models were used for analyses.
Results
Seven-day PPA at 6-months was significantly higher among light smokers (30.6%) than heavier smokers (26.0%; OR=1.25, 95% CI=1.18-1.33, p<0.001). Heavier smokers were prescribed more weeks of NRT than light smokers (B=0.82, 95% CI= 0.64-1.0, p<0.001). The association between smoking cessation and daily NRT dose did not differ between groups (p=0.98). However, a stronger positive relationship between the number of clinic visits attended and 7-day PPA was found among heavier smokers in comparison to light smokers (p<0.001). All findings remained significant after adjusting for baseline variables.
Conclusion
There is a paucity of scientific literature on the effectiveness of NRT for light smokers. Our findings suggest that individualized doses of NRT may be helpful in these sub-populations, and highlights the different treatment needs of light smokers.
Implications
Current clinical guidelines do not provide formal recommendations for light smokers who want to quit smoking. Similar to heavy smokers, light smokers are at substantial risk for many adverse health problems. As such, it is important to understand what treatment options are effective in assisting light smokers to quit smoking. Findings from this study support the use of personalized treatment for all smokers who are interested in quitting smoking, including light smokers.
Background
Smoking is a chronic and relapsing disease, with up to 60% of quitters relapsing within the first year. Transcranial Direct Current Stimulation (tDCS), targets cortical circuits and acutely reduces craving and withdrawal symptoms among cigarette smokers. However, the efficacy of tDCS as an adjunct to standard smoking cessation treatments has not been studied. This study aims to investigate the effectiveness of tDCS in combination with varenicline for smoking cessation. We hypothesize that active tDCS combined with varenicline will improve cessation outcomes compared to sham tDCS combined with varenicline.
Methods
This is a double-blind, sham-controlled randomized clinical trial where fifty healthy smokers will be recruited in Toronto, Canada. Participants will be randomized 1:1 to either active tDCS (20 minutes at 2 mA) or sham tDCS (30 seconds at 2 mA, 19 minutes at 0 mA) for 10 daily sessions (2 weeks) plus 5 follow up sessions, occurring every two weeks for 10 weeks. All participants will be given standard varenicline treatment concurrently for the 12-week treatment period. The primary outcome is 30 day continuous abstinence at end of treatment, confirmed with urinary cotinine. Measurements made at each study visit include expired carbon monoxide, self-reported craving and withdrawal. Three magnetic resonance imaging (MRI) scans will be conducted: two at baseline and one at end of treatment, to assess any functional or structural changes following treatment.
Discussion
For every two smokers who quit, one life is saved from a tobacco-related mortality. Therefore, it is important to develop new and more effective treatment approaches that can improve and maintain long-term abstinence, in order to decrease the prevalence of tobacco-related deaths and disease. Furthermore, the addition of longitudinal neuroimaging can shed light on neural circuitry changes that might occur as a result of brain stimulation, furthering our understanding of tDCS in addiction treatment.
Trial registration
This trial has been registered with Clinicaltrials.gov: NCT03841292 since February 15th 2019 (https://clinicaltrials.gov/ct2/show/NCT03841292)–retrospectively registered.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.