Association between VTE and antibiotic prophylaxis guideline compliance and patient-reported outcomes after total hip and knee arthroplasty: an observational study.

BACKGROUND: Surgical site infection (SSI) and venous thromboembolism (VTE) are associated with high burden and cost and are considered largely preventable following total knee or hip arthroplasty (TKA, THA). The risk of developing VTE and SSI is reduced when prophylaxis is compliant with evidence-based clinical guidelines. However, the association between VTE and antibiotic prophylaxis clinical guideline compliance and patient-reported outcome measures (PROMs) after THA/TKA is unknown. This study aims to explore whether care that is non-compliant with VTE and antibiotic guideline recommendations is associated with PROMs (Oxford Hip/Knee Score and EQ-5D Index scores) at 90- and 365-days after surgery. METHODS: This prospective observational study included high-volume arthroplasty public and private sites and consenting eligible participants undergoing elective primary THA/TKA. We conducted multiple linear regression and linear mixed-effects modelling to explore the associations between non-compliance with VTE and antibiotic guidelines, and PROMs. RESULTS: The sample included 1838 participants. Compliance with VTE and antibiotic guidelines was 35% and 13.2% respectively. In adjusted modelling, non-compliance with VTE guidelines was not associated with 90-day Oxford score (ß = - 0.54, standard error [SE] = 0.34, p = 0.112) but was significantly associated with lower (worse) 365-day Oxford score (ß = - 0.76, SE = 0.29, p = 0.009), lower EQ-5D Index scores at 90- (ß = - 0.02 SE = 0.008, p = 0.011) and 365-days (ß = - 0.03, SE = 0.008, p = 0.002).. The changes in Oxford and EQ-5D Index scores were not clinically important. Noncompliance with antibiotic guidelines was not associated with either PROM at 90- (Oxford: ß = - 0.45, standard error [SE] = 0.47, p = 0.341; EQ-5D: ß = - 0.001, SE = 0.011, p = 0.891) or 365-days (Oxford score: ß = - 0.06, SE = 0.41, p = 0.880 EQ-5D: ß = - 0.010, SE = 0.012, p = 0.383). Results were consistent when complications were included in the model and in linear mixed-effects modelling with the insurance sector as a random effect. CONCLUSIONS: Non-compliance with VTE prophylaxis guidelines, but not antibiotic guidelines, is associated with statistically significant but not clinically meaningful differences in Oxford scores and EQ-5D Index scores at 365 days.