Patterns of pharmacotherapy and health care utilization and costs prior to total hip or total knee replacement in patients with osteoarthritis.

OBJECTIVE: To examine patterns of pharmacotherapy and health care utilization and costs prior to total knee replacement (TKR) or total hip replacement (THR) in patients with osteoarthritis (OA).
METHODS: Using a large US health insurance claims database, we identified all patients with OA who were ages ≥40 years and had undergone TKR or THR between January 1, 2006 and December 31, 2007. Patients with <2 years of complete data prior to TKR or THR were excluded, as were those with evidence of other conditions for which TKR or THR may be performed (e.g., rheumatoid arthritis). We then examined patterns of health care utilization and costs over the 2-year period preceding surgery.
RESULTS: A total of 16,527 patients met all study entry criteria. Their mean ± SD age was 56.6 ± 6.1 years, and 56% of them were women. In the 2 years preceding surgery, 55% of patients received prescription nonsteroidal antiinflammatory drugs, 58% received opioids, and 50% received injections of corticosteroids. The numbers of patients receiving these drugs increased steadily during the presurgery period. The mean ± SD total health care costs in the 2 years preceding surgery were $19,466 ± 29,869, of which outpatient care, inpatient care, and pharmacotherapy represented 45%, 20%, and 20%, respectively. Costs increased from $2,094 in the eighth calendar quarter prior to surgery to $3,100 in the final quarter.
CONCLUSION: Patients with OA who undergo THR or TKR have relatively high levels of use of pain-related pharmacotherapy and high total health care costs in the 2-year period preceding surgery. Levels of utilization and cost increase as the date of surgery approaches.