WEDNESDAY, July 27 (HealthDay News) — Pre-operative smoking status is a significant predictor of 30-day postoperative complications and mortality at one year in patients undergoing elective primary total knee replacement or primary total hip replacement surgery (TKR/THR), according to a study published online July 18 inArthritis Care & Research.

Jasvinder A. Singh, M.B.B.S., M.P.H., from the University of Alabama at Birmingham, and colleagues assessed the impact of smoking on postoperative complications in 33,336 patients, 30 days after elective primary TKR or THR surgery, between 2001 and 2008. Regression models, adjusted for age, race/ethnicity, work relative value units, American Society of Anesthesiologists classification, and year of surgery, with additional adjustments for wound classification for surgical site infections, were used to analyze data from the national Veterans Affairs Surgical Quality Improvement Program. Eighty percent of the patients were Caucasian and 95 percent were male, with an average age of 64 years. Twenty-four percent of the patients were current smokers, 19 percent were prior smokers, and 57 percent had never smoked.

The investigators found that, compared to never smokers, patients who currently smoked had a significantly higher likelihood of surgical site infections (odds ratio [OR], 1.41), stroke (OR, 2.61), one-year mortality (OR, 1.63), and pneumonia (OR, 1.53). Compared to non-smokers, prior smokers had a significantly higher likelihood of pneumonia (OR, 1.34), urinary tract infection (OR, 1.26), and stroke (OR, 2.14).

“Current smoking at the time of elective THR or TKR is associated with increased post-arthroplasty complications, especially surgical site infections and pneumonia. Pre-operative smoking cessation programs should be considered in patients undergoing elective THR or TKR,” the authors write.

One of the study authors disclosed financial ties to the pharmaceutical industry.