Improving Smoking Cessation After Myocardial Infarction by Systematically Implementing Evidence-Based Treatment Methods: A Retrospective Observational Cohort Study

Abstract Background: Evidence-based methods for aiding smoking cessation post-myocardial infarction are effective yet underused in clinical practice. We compared the odds of smoking cessation at 2-months post-myocardial infarction before versus after implementing a set of pre-specified routines optimizing evidence-based treatment methods for smoking cessation, initiated during admission. Methods: Structured routines for early smoking cessation counselling and treatment optimization were implemented at six cardiac rehabilitation centres in Sweden. The routines included cardiac rehabilitation nurses providing current smokers hospitalized for acute myocardial infarction with short consultation, written material, and optimal dosage of nicotine replacement therapy during admission, increasing early prescription of varenicline for eligible patients, and contacting the patients by telephone 3-5 days after discharge, after which usual care follow-up commenced. Centres were also encouraged to strive for continuity in nurse-patient care. Using logistic regression, we compared the odds for smoking cessation at 2-months post-discharge for currently smoking patients admitted (a) before (n=188, median age 60 years, 23% females) and (b) after (n=195, median age 60 years, 29% females) routine implementation. Secondary outcomes included adherence to implemented routines and the association of each routine with smoking cessation odds at 2-months.Results: In total, 159 (85%) and 179 (92%) of enrolled patients attended the 2-month follow-up, before and after implementation of the new routines. After implementation, a significantly larger proportion of patients (65% vs 54%) were abstinent from smoking at 2-months (OR 1.60 [1.04-2.48], p=0.034). Including only those counselled during admission (n=89), 74% (vs 54%) were abstinent at 2-months (OR 2.50 [1.42-4.41], p=0.002). After the new routine implementation patients were counselled more frequently during admission (50% vs 6%, p<0.001), prescribed varenicline at discharge or during follow-up (23% vs 7%, p<0.001), and contacted by telephone during the first week post-discharge (18% vs 2%, p<0.001), compared to before. Being prescribed varenicline before discharge or during follow-up had the strongest independent association with smoking abstinence at 2-months (adjusted OR 4.09 [1.68-10.00], p=0.002).Conclusions: Our results support that readily available methods for aiding smoking cessation can be implemented effectively in routine practice, with possible beneficial effects on smoking cessation for the high-risk group of smoking myocardial infarction patients.