OBJECTIVES: Accounting for high-dose, systemic corticosteroid use is critical for unbiased real-world studies of patients with inflammatory or immunological disorders. Corticosteroids may be administered in multiple forms, recorded as procedure codes for injections or infusions (HCPCS) or pharmacy-dispensed medications (NDC). Understanding the patterns of corticosteroid coding is important for the valid design of real-world studies.

METHODS:Patients initiating immunoglobulins (Ig) for the treatment of chronic inflammatory demyelinating polyneuropathy (CIDP) or primary immunodeficiency (PID) were identified in IBM Watson MarketScan Research Databases. The use of high-dose systemic corticosteroids was evaluated via HCPCS and NDC and patients identified by each code were compared.

RESULTS:

Among 3,975 CIDP patients initiating Ig, 2,268 (57.1%) had prior high-dose corticosteroid use. HCPCS identified use in 1,579 (39.7%) patients and NDC codes in 998 (25.1%) patients. Patients with HCPCS were older, more likely to be male, from the south, receiving outpatient Ig, and to have history of back pain, CNS disorders, diabetes, vascular conditions, and osteoarthritis than those with NDC; patients with HCPCS were less likely to have deep vein thrombosis, opioids, and prior immunomodulating agents than patients with NDC.

Among 17,937 PID patients initiating Ig, 11,576 (64.6%) had prior high-dose corticosteroid use. HCPCS identified prior use in 8,826 (76.2%) patients and NDC in 6,342 (54.8%) patients. Patients with HCPCS were older, more likely to be female, from the south, receiving outpatient Ig, using Medicare insurance, and to have history of cancer, vascular conditions, fibromyalgia and irritable bowl, and obesity than those with NDC; patients with HCPCS were less likely to have history of respiratory and thromboembolic conditions, and lower disease severity based on other medication use and Risk Vita Sign score than patients with NDC.

CONCLUSIONS:

HCPCS and NDC identification of high-dose corticosteroids may elucidate differences in patient populations and should be considered in real-world evidence studies.