SP9.14 Prevalence, trends and outcomes from smoking in elective surgical systems: A pre-planned secondary analysis of a prospective cohort study across 442 hospitals from 29 countries across Europe

Introduction Smoking remains a public health issue in Europe, with elective surgery offering a key opportunity for intervention. This study aims to address this gap in a large observational prospective cohort study of patients undergoing abdominal surgery across Europe. Methods We performed a pre-planned secondary analysis of a prospective, international cohort study of patients undergoing elective abdominal surgery between January 24, and May 03, 2022. Multilevel logistic regression was used to explain the relationship between preoperative smoking status on postoperative overall (primary outcome) and major (secondary outcome) complications. Findings 16,327 patients from 442 hospitals across 29 countries were included. 3,179 patients (19.5%) were current smokers, ranging from 8.3% to 31.7% across the included countries. Rates of current smokers were higher in younger patients (18-40 vs 41-60 vs 61-80 vs ≥81 years: 26.8% vs 25.3% vs 15.1% vs 5.2%), male patients (compared to females: 22.1% vs 17.2%) and healthy adults (compared to one or two long-term conditions: 24.6% vs 19.6% vs 16.6%). 30-day overall complications were higher across current (OR: 1.14; 95% CI:1.03-1.27), ex-smoker <6 weeks (1.52, 1.10-2.10), ex-smoker 6 weeks - 1year (1.30, 1.01-1.68) and ex-smoker >1 year (1.13, 1.02-1.26) compared to never smokers. No difference was seen for 30-day major complications across these groups. Interpretation The high prevalence of smoking among elective surgical patients, especially in younger, healthy patients, expose a need to strengthen preoperative cessation strategies. Although uncertainty exist around perioperative outcomes, smoking cessation in the perioperative window is a good opportunity to reach people for long-term health promotion.