By Pam Harrison
The most important factor associated with an increased risk of revision following total knee arthroplasty (TKA) is smoking and patients who smoke should be advised to stop smoking to decrease their risk of revision, authors of a case-control study said.
In a multivariate analysis of factors associated with TKA revision, smoking was associated with a nearly threefold increased risk (odds ratio 2.87, 95% CI 1.33-6.19), reported Benedict Nwachukwu, MD, of the Hospital for Special Surgery in New York City, and colleagues in BMC Musculoskeletal Disorders. 
The study covered 436 patients who had undergone TKA at a tertiary center over a 13-year period: 146 who had undergone both a primary and revision TKA (cases) and 290 patients with a primary TKA without an identified revision (controls).
Male sex was also associated with increased risk of revision (OR 1.73, 95% CI 1.06-2.81). Conversely, older age was associated with a 17% lower risk of requiring a revision for each 5-year increment increase in age (OR 0.83; 95% CI 0.75-0.92).