Patient reported allergies are a risk factor for poor outcomes in total hip and knee arthroplasty

We evaluated 459 patients undergoing THA or TKA who completed preoperative and postoperative WOMAC and/or SF36 surveys. Medical comorbidities and reported allergies were also recorded. Evaluation of surveys was compared for patients with or without 4 or more reported allergies using statistical methods. Patients with 4 or more reported allergies had less improvement on SF36 Physical Component Score (∆PCS=4.2) than those with 0-3 allergies (∆PCS=10.0, P=0.0002). Regression analysis showed that this change was independent of self-reported comorbidities. Patients reporting 4 or more allergies also had less improvement in WOMAC function (∆F=21.4) than those with 0-3 allergies (∆F = 27.2, P=0.036). Similar nonsignificant trends occurred in SF36 mental and WOMAC pain and stiffness scores.