Study Finds Smoking Increases infection Risk

Here is another reason to quit—after joint replacement surgery smokers are at an increased risk of reoperation because of infection. This was the result of a study published in the February 15 issue of The Journal of Bone & Joint Surgery and led by senior author Matthew S. Austin, M.D., of the Rothman Institute at Thomas Jefferson University, Philadelphia. Austin’s study included data on 15,264 patients who underwent a total of 17, 391 total joint replacements between 2000 and 2013. There were 8,917 hip and 8,477 knee replacements in the study.

“Our results found that current smokers had a significantly higher rate of septic reoperation compared with nonsmokers,” commented Austin “Furthermore, each additional pack-year significantly contributed to total reoperations.”

At the time of their surgery, 9% of patients were current smokers, 34% were former smokers, and 57% were nonsmokers. Current smokers were younger than were the nonsmokers. The current smoker’s average age was about 58 versus 63 years. Smokers also had higher rates of major respiratory and cardiovascular diseases.

After making adjustments for other characteristics, the researchers found that current smokers had a significantly increased risk of reoperation for infectious complications. The relative risk, compared to nonsmokers, was 80% higher. As a group, former smokers were not at increased risk.

For current and former smokers alike, the risk of 90-day non-operative readmission increased with the number of “pack-years” smoked. Smoking an extra pack per day for a decade was associated with a 12% increase in that relative risk.

“If smoking is associated with elevated perioperative risk of readmission and/or reoperation, then it may be reasonable to engage the patient in a smoking cessation program prior to total joint arthroplasty,” Austin and co-authors wrote in their research report.