Effect of various durations of smoking cessation on postoperative outcomes: A retrospective cohort analysis.

Background: Preoperative smoking cessation is commonly advised in an effort to improve postoperative outcomes. However, it remains unclear for how long smoking cessation is necessary, and even whether a brief preoperative period of abstinence is helpful and well tolerated.
Objective: We evaluated associations between various periods of preoperative smoking cessation and major morbidity and death.
Design: Retrospective cohort analysis.
Setting: Adults who had noncardiac surgery at the Cleveland Clinic Main Campus between May 2007 and December 2013.
Patients: A total of 37 511 patients whose smoking history was identified from a preoperative Health Quest questionnaire. Of these patients, 26 269 (70%) were former smokers and 11 242 (30%) were current smokers. Of the current smokers, 9482 (84%) were propensity matched with 9482 former smokers (36%). We excluded patients with American Society of Anesthesiologists' physical status exceeding four, patients who did not have general anaesthesia, and patients with missing outcomes and/or covariables. When multiple procedures were performed within the study period, only the first operation for each patient was included in the analysis.
Main Outcome Measures: The relationship between smoking cessation and in-hospital morbidity/mortality.
Results: The incidence of the primary composite of in-hospital morbidity/mortality was 6.9% (656/9482) for all former smokers; the incidence was 7.8% (152/1951) for patients who stopped smoking less than 1 year before surgery, 6.3% (118/1977) for 1 to 5 years, 7.2% (115/1596) for 5 to 10 years and 6.9% (271/3457) for more than 10 years.
Conclusion: Smoking cessation was associated with reduced in-hospital morbidity and mortality which was independent of cessation interval.