Economic impact of venous thromboembolism following major orthopaedic surgery in Japan

Objectives: Venous thromboembolism (VTE) is the most frequent complication following major orthopaedic surgery (MOS). Although studies in Western populations have demonstrated significantly higher costs for patients with VTE versus those without VTE after MOS, there is a paucity of such data in Japan. This study was conducted to understand the costs and VTE rates in Japanese patients. Methods: Data were extracted from a hospital claims database. MOS was defined as total hip replacement, total knee replacement, or hip fracture repair. Subjects who underwent more than one MOS during the same admission were excluded. Identified VTE cases were matched on a 1:2 matching scheme on the basis of surgery type, hospital, and date of surgery (±6 months). The primary outcome was the difference in 90-day costs. Secondary outcomes included differences in total 6-month costs postsurgery and average length and cost of initial hospital stay. Results: The 90-day cumulative VTE incidence was 0.774%, with 94% of the cases occurring within 30 days postsurgery. Total 90-day costs were significantly higher in patients with VTE (difference of 864,153 Japanese yen [US $10,538]). Average length of stay was longer for patients with VTE (66 days vs. 42 days). Costs incurred by patients with VTE were on average much higher than those incurred by patients without VTE throughout 5 months postsurgery. Conclusions: The development of a VTE in patients undergoing MOS results in a 1.5-fold increase in the length of stay and a 1.7-fold increase in 90-day costs. Findings indicate that the avoidance of VTEs through more effective prophylaxis will help to reduce the economic burden associated with MOS.