Rheumatoid arthritis is associated with higher 90-day Hospital Readmission Rates Compared to Osteoarthritis after Hip or Knee arthroplasty: A cohort study
Jasvinder A. Singh, MBBS, MPH,1,2,3 Maria C.S. Inacio, PhD,4 Robert S. Namba, MD,5 and Elizabeth W. Paxton, MA4Hip Knee
Objective
To examine if an underlying diagnosis of rheumatoid arthritis (RA) or osteoarthritis (OA) impacts the 90-day readmission rates after total hip or knee arthroplasty (THA or TKA).
Methods
Prospectively collected data from an integrated healthcare system Total Joint Replacement Registry of adults with RA or OA undergoing unilateral primary THA or TKA during 2009-2011 were analyzed. Adjusted logistic regression models for 90-day readmission were fit. Odds ratios with 95% confidence intervals (CI) were calculated. Study year was an effect modifier for the outcome, therefore separate analyses were conducted for each of the three study years.
Results
Of the 34,311 patients, 496 had RA and 33,815 had OA. Comparing RA and OA, there were: 73% and 61% women; 45% and 70% Caucasians; and the mean age was lower, 61 vs. 67 years (p<0.001). Respective crude 90-day readmission rates were 8.5% and 6.7%. The adjusted odds of 90-day readmission increased from year to year for RA compared to OA patients, from 0.89 (95% CI, 0.46-1.71) in 2009 to 1.34 (95% CI, 0.69-2.61) in 2010 to 1.74 (95% CI, 1.16-2.60) in 2011. The two most common readmission reasons were: joint prosthesis infection (10.2%) and septicemia (10.2%) in RA; joint prosthesis infection (5.7%) and other postoperative infection (5.1%) in OA.
Conclusions
RA is a risk factor for 90-day readmission after primary TKA or THA. An increasing risk of readmissions noted in RA in 2011 is concerning and indicates further studies should examine the reasons for this increasing trend.
Link to article