Analgesic usage for low back pain: impact on health care costs and service use.

STUDY DESIGN: Cross-sectional analysis of analgesic use by patients with low back pain (LBP).

OBJECTIVES: To describe patterns of analgesic use and their cost implications for the use of other care services among individuals with LBP enrolled in a health insurance plan during 2001. It was hypothesized that the use of analgesics would be most frequent among patients with LBP with neurologic findings.

SUMMARY OF BACKGROUND DATA: National guidelines have recommended analgesics as the primary pharmacologic treatment of LBP. The choice of specific analgesics has major cost and service use implications.

METHODS: The University of Pittsburgh Health System includes 18 affiliated hospitals, more than 5000 physicians, and a commercial health plan with 255,958 members in 2001. This study uses the System Health Plan's insurance claims database to identify members who had services provided for one of 66 International Classification of Diseases, Version 9, Clinical Modification codes that identify mechanical LBP (n = 17,148).

RESULTS: In 2001, 7631 (43.5%) members with claims for LBP services had no analgesic pharmacy claims. The other 9517 (55.5%) had analgesics claims costing a total of $1.4 million; 68% of claimants were prescribed an opioid and 58% nonselective nonsteroidal antiinflammatory drugs (NSAID). The costs of opioids, NSAID, and cyclooxygenase-2 selective NSAID for patients with LBP represented 48%, 24%, and 28%, respectively, of total health plan expenditures for all uses of these drugs, including cancer. Opioid use was associated with the high volume usage of LBP care services. Patients with LBP with and without neurologic involvement and those with acquired lumbar spine structural disorders had similar patterns of analgesic use: those with congenital structural disorders were less likely to use analgesics; and those with psychogenic pain and LBP related to orthopedic devices were more likely to use opioids.

CONCLUSIONS: With this health plan, a high proportion of patients with LBP had claims for opioids during 2001. The use of opioids by patients with LBP represents a major cost for the health plan, and is associated with specific patient characteristics and their use of other LBP services.