RESUMEN
Purpose: To investigate the performance of ultrasonography (US) for the detection of knee osteoarthritis (OA) in patients suffering from knee pain, compared to conventional radiographs. Methods: Cross-sectional study performed at a university teaching hospital. Consecutive patients complaining of unilateral or bilateral mechanical knee pain who signed an informed consent were included. All patients underwent simultaneously an ultrasonographic and a radiographic evaluation of the knee. Exclusion criteria were age under 18 years, prior diagnosis of knee OA, diagnosis of inflammatory arthritis, history of knee surgery or trauma, severe knee deformities, and corticosteroid injection within the last 2 months. The diagnostic properties of US for the detection of knee OA were evaluated using radiological data as the reference method. Evaluated test properties were sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and the positive and negative likelihood ratio (LR+ and LR-). Results: Three-hundred twenty-two knees (281 patients) were included. Radiographic degenerative changes were present in 56.8% (183) of the evaluated knees. Regarding the diagnostic properties of the US, the presence of either osteophytes or the compromise of the femoral hyaline cartilage had the best sensitivity to detect OA (95%), with a NPV of 92% and a LR- of 0,07, while the combined identification of osteophytes and compromise of the femoral hyaline cartilage had the best specificity (94%), with 94% PPV and a LR+ of 13. Conclusion: US demonstrated an excellent sensitivity with an adequate specificity for the detection of radiographic knee OA.
RESUMEN
OBJECTIVES: To describe the process and results of the implementation of a performance-based risk-sharing arrangement for the use of certolizumab pegol (Cimzia) in patients with rheumatoid arthritis (RA), based on rational pharmacotherapy. METHODS: In 2014, the area of Management of Drugs and Supplies of the health maintenance organization of the Hospital Italiano de Buenos Aires signed a performance-based risk-sharing arrangement with Montpellier Laboratory for the use of certolizumab pegol in patients with RA. The laboratory would reimburse the hospital the cost of the first 10 doses of the drug if an optimal clinical response was not achieved (difference greater than or equal to 1.2 in the Disease Activity Score 28 with erythrocyte sedimentation [Δ DAS28 ESR] measured at the beginning and at the end), or if the patient presented with an adverse drug reaction, during the first 12 weeks of treatment. RESULTS: Forty patients with RA were included between September 2014 and January 2018. Thirty-six patients completed 12 weeks of treatment, of which 25 (69.4 %) had an optimal clinical response (Δ DAS28 ESR ≥ 1.2). The laboratory reimbursed the hospital 116 doses of certolizumab pegol, corresponding to 12 patients (12 of 40, 30%). Eleven of them did not reach the optimal clinical response, and 1 presented with an adverse drug reaction. CONCLUSIONS: The performance-based risk-sharing arrangement proved to be a useful tool to optimize the resources of the healthcare payer and contributed to the collection of scientific evidence in real-life patients.