Venous thromboembolism (VTE), which includes deep vein thrombosis (DVT) and pulmonary embolism (PE), is a leading cause of morbidity and mortality in US patients undergoing total hip, or total knee replacement (THR/TKR) surgery. We evaluated the impact of duration of thromboprophylaxis on VTE and bleeding events in patients after THR/TKR surgery.
This retrospective study was based on claims data from a large US health plan database linked to an inpatient database. Patients aged ≥18 years, underwent THR/TKR surgeries between 04/01/2004 and 12/31/2006, and had thromboprophylaxis with an ACCP-recommended agent for ≥1 day post-surgery. Patients with evidence of VTE, or who underwent orthopaedic surgery 90 days prior to THR/TKR surgery were excluded. Outcomes included VTE, DVT, PE, and major and minor bleeding events. Bivariate comparisons between short-duration (≤14 days) and extended-duration (≥15 days) outcomes were based on chi-squared tests. Logistic regression was used to assess the impact of short-duration vs extended-duration thromboprophylaxis on outcomes; adjustments were made for age, geographic region, baseline comorbidity score, as well as THR/TKR surgery, duration of thromboprophylaxis, and oral vs injectable prophylactic agent.
Of 3,195 qualified patients (THR (1123), TKR (2072)), 67% received short-duration, while 33% received extended-duration thromboprophylaxis. Based on unadjusted analysis by surgery type (Table 1), patients who were given short-duration thromboprophylaxis vs extended-duration thromboprophylaxis had more VTE events; benefits were statistically significant in the TKR group. In combined group, patients with shorter-duration prophylaxis were approximately 3 (3.96% vs 1.43%; p<0.0001), 2 (2.84% vs 1.24%; p<0.0001), 6 (1.12% vs 0.19%; p=0.0052) and 4 (1.68% vs 0.38%; p=0.0011) times more likely to experience a VTE, DVT, PE, or major bleeding event, respectively. The risk-adjusted results are similar (Table 2).
Approximately two out of three patients who underwent THR/TKR surgery received thromboprophylaxis for ≤14 days. These patients had significantly higher rates of VTE, DVT, PE, and major bleeding than patients who received prophylaxis for ≥15 days.
The presented data suggest that extended-duration thromboprophylaxis for patients undergoing THR/TKR surgery is clinically beneficial.
Wells Philip, Consultant fee, speaker bureau, advisory committee, etc. Johnson & Johnson; No Product/Research Disclosure Information