How Does Gout Impact Outcomes Following Primary Shoulder Arthroplasty?: Gout and Shoulder Arthroplasty

Studies have shown that the overall prevalence of gout has increased. Data shows that patients with gout have worse outcomes following total joint arthroplasty, however studies investigating the effects of gout following primary total shoulder (TSA) and reverse shoulder arthroplasty (RSA) are limited. The purpose of this study was to compare outcomes of patients with and without gout undergoing primary shoulder arthroplasty, evaluating (1) in-hospital length of stay (LOS); (2) medical complications; (3) cost of care. A retrospective query using a nationwide administrative claims database was performed from January 2005 to March 2014 for all patients who underwent primary TSA and RSA for the treatment of glenohumeral osteoarthritis, yielding a total of 11,414 patients to be included. For the TSA cohort, 7702 patients were identified within the study (n = 1,185) and control (n = 6417) cohorts. Similarly, 3712 patients were identified within the RSA cohorts (gout n = 621 and control n = 3,091). Primary endpoints were in-hospital LOS, 90-day medical complications, and total global 90-day episode of care (EOC) costs. Multivariate logistic regression analyses were used to calculate the odds (OR) of medical complications, whereas Welch's t-tests were used to compare LOS and costs of care. A P value less than .05 was considered statistically significant. Patients with gout undergoing primary TSA (3- vs. 2-days, P < .0001) and RSA (3- vs. 2-days, P < .0001) had significantly longer in-hospital LOS. Gout patients undergoing either TSA (41.2 vs. 11.3%; OR: 3.30, P < .0001) or RSA had significantly higher incidence and odds (50.6 vs. 17.9%; OR: 2.10, P < .0001) of developing 90-day medical complications compared to their counterparts. Study group patients incurred significantly higher total global 90-day episode of care costs following both TSA ($15,007.84 vs. $13,447.06, P < .0001) and RSA ($19,659.27 vs. $16,783.70, P< .0001). This study demonstrates that patients with gout undergoing primary shoulder arthroplasty have longer in-hospital LOS, in addition to higher rates of complications, and increased costs of care. The study can be used by orthopedic surgeons to educate patients who have gout on complications which may occur following their surgical procedure. Level III, retrospective comparative study.