The impacts of rheumatoid arthritis (RA) on perioperative risks among patients undergoing revision total knee arthroplasty (rTKA) have not been investigated yet. Thus, we hypothesized that patients with RA sustained increased perioperative risks and higher resource consumption burdens as compared to patients with osteoarthritis (OA) during the perioperative period.
The National Inpatient Sample (NIS) database was used to compare the demographic characteristics, major in-hospital complications, resource consumptions, and in-hospitalization mortality between patients with RA and OA after rTKA. A 1:1 propensity score-matching, χ2 test, independence-sample T-test, and logistic regression analysis were done in statistical analyses to answer our hypotheses.
4.3% (6363/132,405) of rTKA patients were diagnosed with RA. They tended to be women and received revision for infection but with similar ages as compared to patients with OA. Except for acute postoperative anemia (odds ratio [OR] = 1.196), blood transfusion (OR = 1.179), prolonged hospitalization (OR = 1.049), and higher total cost (OR = 1.145), patients with RA sustained decreased odds of acute renal failure (OR = 0.804) and urinary complications (OR = 0.467). Besides, the other observed in-hospital complications showed no differences between patients with RA and OA.
Despite consuming greater in-hospital resources, patients with RA did not suffer increased odds of most in-hospital complications and in-hospital mortality for a revision TKA during the perioperative period. Compared with patients with OA, patients with RA sustained equivalent perioperative risks in the United States between 2002 and 2014.