Interventions in the preoperative clinic for long term smoking cessation: a quantitative systematic review

To assess the efficacy of interventions offered to patients in the preoperative clinic to promote long-term (> or = three months) smoking cessation following surgery.

We searched The Cochrane Library, MEDLINE, EMBASE and CINAHL for all randomized controlled trials (RCTs) on smoking-cessation interventions initiated in the preoperative clinic. Trial inclusion, quality assessment, and data extraction were performed independently by two authors. Standard meta-analytic techniques were applied.

Four RCTs (n = 610 patients) were included in the review. Interventions included pharmacotherapy, counseling, educational literature and postoperative telephone follow-up. The follow-up period ranged between three to 12 months with only one RCT following up patients for > one year. Two studies used biochemical methods to validate subjects' self-reporting of smoking cessation at the follow-up assessment. Overall, the interventions were associated with a significantly higher cessation rate vs control at the three to six month follow-up period (pooled odds ratio: 1.58, 95% confidence interval (CI) 1.02-2.45, P value = 0.01, I(2) = 0%). The only trial with longer follow-up period (12 months), however, failed to show any significant difference between the intervention and control groups (odds ratio: 1.05, 95% CI 0.53-2.09, P value = 0.88).

This systematic review suggests that smoking-cessation interventions initiated at the preoperative clinic can increase the odds of abstinence by up to 60% within a three- to six-month follow-up period. To evaluate the possibility of longer abstinence, future trials with at least one-year follow-up are recommended.