Duloxetine use in chronic low back pain: treatment patterns and costs.

BACKGROUND: Little is known about the real-world treatment patterns and costs of patients with chronic low back pain (CLBP) who are treated with duloxetine compared with those receiving other non-surgical treatments. OBJECTIVE: Our objective was to compare the real-world treatment patterns and costs between patients with CLBP who initiated duloxetine and matched controls who initiated another non-surgical treatment. METHODS: The study sample was selected from a US privately insured claims database (2004-8). Selected patients were aged 18-64 years, and had a low back pain (LBP) diagnosis (per Healthcare Effectiveness Data and Information Set [HEDIS] specifications) with a subsequent CLBP-qualifying diagnosis recorded ≥90 days after the initial LBP diagnosis. Duloxetine-treated patients had ≥1 duloxetine prescription within 6 months after CLBP diagnosis, no prior duloxetine claim, and continuous eligibility ≥12 months before first LBP diagnosis and ≥6 months after index duloxetine prescription (study period). Because duloxetine patients had higher rates of co-morbidities, 553 duloxetine-treated patients were matched to 553 control patients who initiated another non-surgical LBP treatment based on propensity score and time from first LBP diagnosis to treatment initiation. A subset (n = 103 each) of matched employees with disability data was also analysed to assess work loss. Main outcomes measures included study period treatment rates and direct (medical and drug) costs from a third-party payer perspective and employee indirect (work-loss) costs. McNemar tests were used to compare LBP treatment rates. Bias-corrected bootstrapping t-tests were used to compare costs. RESULTS: After matching, the two groups had balanced baseline characteristics including demographics, LBP diagnostic categories, co-morbidity profiles, resource use, treatment patterns and mean direct costs. During the 6-month study period, matched duloxetine-treated patients had significantly lower rates of other pharmacological therapy (e.g. 56.2% vs 64.9% narcotic opioids, p = 0.0024; 34.9% vs 49.5% NSAIDs, p < 0.0001) and non-invasive therapy (28.8% vs 38.5% chiropractic therapy, p = 0.0007; 25.5% vs 35.4% physical therapy, p = 0.0004; 17.5% vs 28.4% exercise therapy, p < 0.0001) than controls. Duloxetine-treated patients versus controls had similar back surgery rates (2.2% vs 3.8%; p = 0.1127) and similar direct costs ($US7658 vs $US7439; p = 0.8119). Among CLBP employees, duloxetine-treated employees versus controls had lower rates of other non-surgical therapy, similar back surgery rates (0.0% vs 3.9%; p = 0.1250), lower total direct and indirect costs ($US5227 vs $US7299; p = 0.0418), and similar indirect costs ($US1806 vs $US2664; p = 0.0528). CONCLUSIONS: Duloxetine treatment in CLBP patients/employees versus other non-surgical treatment was associated with reduced rates of non-surgical therapies and similar back surgery rates, without increased costs.

Real-world practice patterns, health-care utilization, and costs in patients with low back pain: the long road to guideline-concordant care.

BACKGROUND CONTEXT: Treatment guidelines suggest that most acute low back pain (LBP) episodes substantially improve within a few weeks and that immediate use of imaging and aggressive therapies should be avoided. PURPOSE: Assess the actual practice patterns of imaging, noninvasive therapy, medication use, and surgery in patients with LBP, and compare their costs to those of matched controls without LBP. STUDY DESIGN: A retrospective analysis of claims data from 40 self-insured employers in the United States. PATIENT SAMPLE: The study sample included 211,551 patients, aged 18 to 64 years, with one LBP diagnosis or more (per Healthcare Effectiveness Data and Information Set specification) during 2004 to 2006, identified from a claims database. Patients had continuous eligibility for 12 months or more after their index LBP diagnosis (study period), for 6 months or more before their index diagnosis (baseline period), and no other LBP diagnosis during the baseline period. Patients with LBP were matched to a random cohort of patients without LBP by age, gender, employment status, and index year. OUTCOMES MEASURES: Physiological measures (eg, imaging and diagnostic tests), functional measures (eg, pharmacologic and nonpharmacologic treatment for LBP, health-care resource use), and direct (medical and prescription drug) and indirect (disability and medically related absenteeism) costs were assessed within the year after the LBP diagnosis. METHODS: Univariate analyses described treatment patterns and compared baseline characteristics and study period costs. RESULTS: Patients with LBP had significantly higher rates of baseline comorbidities and resource use compared with controls. Of patients with LBP, 41.6% had imaging mean (median) [standard deviation] 34.3 (0) [78.6] days after the LBP diagnosis. Most patients with LBP (69.4%) used medications starting 51.9 (8) [86.2] days after the diagnosis. Opioids were commonly prescribed early (41.6% of patients; after 82.8 (25) [105.9] days). Of patients with LBP, 2.05% had surgery during the study period. Patients with LBP were likely to have chiropractic treatment first, followed by pharmacotherapy with muscle relaxants and nonsteroidal anti-inflammatory drugs. Except for less surgery, these findings also held for patients with only nonspecific LBP. Patients with LBP had higher mean direct costs compared with controls ($7,211 vs. $2,382, respectively; p<.0001), with surgery patients having mean direct costs of $33,931. CONCLUSIONS: Contrary to clinical guidelines, many patients with LBP start incurring significant resource use and associated expenses soon after the index diagnosis. Achieving guideline-concordant care will require substantial changes in LBP practice patterns.