The effect of smoking on short-term complications following total hip and knee arthroplasty

Background: Total joint arthroplasty is the most frequently performed orthopaedic procedure in the United States. The purpose of the present study was to identify differences in thirty-day morbidity and mortality following primary total hip and total knee arthroplasty according to smoking status and pack-year history of smoking. Methods: We queried the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database to identify patients who had undergone primary total hip or total knee arthroplasty between 2006 and 2012. Patients were stratified by smoking status and pack-year history of smoking. Thirty-day rates of mortality, wound complications, and total complications were compared with use of univariate and multivariate analyses. Results: We identified 78,191 patients who had undergone primary total hip or total knee arthroplasty. Of these, 81.8% (63,971) were nonsmokers, 7.9% (6158) were former smokers, and 10.3% (8062) were current smokers. Current smokers had a higher rate of wound complications (1.8%) compared with former smokers and nonsmokers (1.3% and 1.1%, respectively; p < 0.001). Former smokers had a higher rate of total complications (6.9%) compared with current smokers and nonsmokers (5.9% and 5.4%, respectively; p < 0.001). Multivariate analysis identified current smokers as being at increased risk of wound complications (odds ratio [OR], 1.47; 95% confidence interval [CI], 1.21 to 1.78), particularly deep wound infection, while both current smokers (OR, 1.18; 95% CI, 1.06 to 1.31) and former smokers (OR, 1.20; 95% CI, 1.08 to 1.34) were at increased total complication risk. Increasing pack-year history of smoking resulted in increasing total complication risk. Conclusions: On the basis of our findings, current smokers have an increased risk of wound complications and both current and former smokers have an increased total complication risk following total hip or total knee arthroplasty. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.