Gout medication treatment patterns and adherence to standards of care from a managed care perspective.

OBJECTIVE: To determine allopurinol treatment patterns and adherence to published standards of care for patients with gout. PATIENTS AND METHODS: This retrospective claims analysis in a managed care database included patients 18 years or older, with continuous eligibility for 1 year before and after the start date and 2 or more visits during which the gout disease code (274.xx) was assigned or 1 or more pharmacy prescriptions for a gout-specific medication between January 1, 2000, and December 31, 2002 (intake period). Factors associated with compliance with allopurinol therapy were measured based on the medication possession ratio, and adherence to 2 quality-of-care indicators for gout management was assessed using multivariable logistic regression analysis. RESULTS: A total of 64.9% of allopurinol users had a modal daily dose or the most commonly observed daily dose of 300 mg/d, median length of therapy was 3 months, and a high proportion of patients had a medication possession ratio of 10% or less. Suggested quality-of-care Indicators for gout had low performance: 53% of patients with renal impairment received a modal daily dose of 300 mg or greater, and 83% of patients who started taking allopurinol did not have their serum urate levels measured within 180 days. Patients with gout flares were less likely to be compliant with allopurinol (odds ratio, 0.50; 95% confidence interval, 0.40-0.63). Patients with renal impairment at baseline were 3.2 times more likely to undergo serum urate testing than patients without renal impairment (odds ratio, 3.20; 95% confidence Interval, 1.25-8.23). CONCLUSION: There was low compliance with allopurinol therapy for treatment of gout. Patients potentially received suboptimal quality of care as measured by serum urate testing and appropriateness of allopurinol dosing in patients with renal impairment.

Serum urate levels and gout flares: analysis from managed care data.

BACKGROUND: The desired serum urate level (SUA) for prevention of gout attacks is widely recommended to be in the subsaturating range, <6.0 mg/dL. OBJECTIVES: The objectives of this study were to evaluate attainment of this target SUA among gout patients on allopurinol in a naturalistic setting and to assess its impact on gout flare risk. METHODS: : This was a retrospective, observational study in a southeastern U.S. managed care organization of approximately 2.2 million members. The first gout claim/prescription within the intake period (January 1, 2000-December 31, 2002) was the index date. Included patients had > or =2 visits with gout International Classification of Diseases, 9th Revision code (274.xx) or > or =1 pharmacy script(s) for allopurinol, colchicine, probenecid, or sulfinpyrazone. Excluded patients were <18 years and/or did not have a 1-year continuous eligibility pre-/postindex date. Gout flares were defined by office/emergency room visit with gout or joint pain code(s) and > or =1 of the following within 7 days of the visit: intraarticular aspiration/injection, joint fluid microscopy, or pharmacy claim for nonsteroidal antiinflammatory drug, colchicine, corticosteroid, or ACTH. Multivariable regression analyses were conducted to evaluate gout flare risk/rate and association with target SUA. RESULTS: Approximately 40% of 5942 gout patients identified used allopurinol postindex. Among allopurinol users with pre-/postindex SUA data (n = 162), mean SUA was lowered from 8.7 mg/dL to 7.1 mg/dL; reduction was significant (P < 0.001). Among allopurinol users who did not have SUA <6.0 mg/dL preindex (n = 147), only 25% reached target levels during postindex. Despite pharmacotherapy, patients with nontarget levels were 59% more likely to flare than those at target. Allopurinol users who were not at target were 75% more likely to flare. CONCLUSION: The failure of allopurinol users to achieve target SUA levels of <6.0 mg/dL may be attributed to lack of awareness of optimal SUA, allopurinol dosing, compliance, and efficacy. Patients who did not achieve target SUA were at increased flare risk.