Introduction:
Taking into account the burden of tobacco in cardiovascular prognosis, smoking cessation should be a priority in secondary prevention programs. We analysed the predictors of relapse after a smoking cessation intervention in coronary disease patients.

Methods:
448 smoker patients (85,5% male) referred to a cardiac rehabilitation program after a recent admission for acute myocardial infarction were analyzed. Most of them were heavy smokers (mean consumption of 24,5 cig/day, 41,2 pack-year). The intervention was based in an average of 3 individual visits during the first 3 months, one group session, and one follow-up visit after 6 months. Diet and exercise counselling was given. First line smoking cessation pharmacotherapy was offered to all patients as a possibility. Smoking abstinence was confirmed with co-oximetry at 3 and 6-month follow-up visits. A multivariate analysis was performed in order to study the predictors of relapse.

Results:
Mean age was 53.6, 57% were hypertensive, 23% diabetic, 60% dislipidaemic, 27% obese and 7% had been previously diagnosed with chronic obstructive pulmonary disease (COPD). Pharmacotherapy for smoking cessation was requested in 31%, varenicline was used in 57% of them, nicotine replacement therapy in 33% and bupropion in 10%. Patients lost to follow-up (3% at month 3, 6% at month 6) were considered as having relapsed. Abstinence rate was 76,6% at month 3, and 71% at month 6. Following a multivariate analysis, the predictors of relapse were found to be the number of cigarettes smoked per day, the number of pack-year, the use of smoking cessation drugs, dropping out of the program, and having a previous condition of COPD.

Conclusions:
Smoking cessation interventions after an acute myocardial infarction are effective. A high degree of motivation facilitates the abstinence even in the absence of pharmacotherapy. A high degree of addiction and dependence, the need of smoking cessation drugs, lack of adherence and a previous condition of COPD were predictors of relapse. A more intense intervention is probably needed in patients with these features.

Funding:
No conflict of interest. No external funding.