INTRODUCTION
Psoriasis is a chronic, immune-mediated, systemic inflammatory
disease afflicting 0.6 to 4.8% of the population.1;2 There is no cure for the disease, necessitating lifelong treatment for management of the clinical symptoms. Patients suffering from psoriasis not only experience significant impact to their health-related quality of life but also face a financial and psychosocial burden.3 Healthcare costs related to psoriasis are increasing as newer and more expensive medications are developed.The estimated annual cost is approximately $11.3 billion.4-6
Treatment options for psoriasis have evolved over time as newer and more effective medications are being discovered.7 Physicians have an endless variety of options and combinations to choose from when picking the most effective therapy to treat their patients.
8 Factors influencing a physician’s decision in choosing the best therapy for a patient include disease severity, therapeutic efficacy,
treatment impact on quality of life, patient preference, cost effectiveness, and the patients’ health insurance.8;9 Treatments vary in their costs, both the out-of-pocket costs to patients and the total societal cost of the medication. For mild psoriasis, treatments
can range from corticosteroids that costs tens of dollars per tube of product to vitamin D analogs, retinoids, tacrolimus, and pimecrolimus which cost hundreds of dollars per tube of product.
Similarly, for moderate to severe psoriasis, there are more affordable treatments, such as methotrexate and cyclosporine, and biologic treatments costing tens of thousands of dollars.10;11
As health insurance status may affect access to treatment, we sought to assess the degree of influence payment type has on physician prescribing patterns in the US ambulatory office setting.
METHODS
This study is a secondary analysis of data collected in the National
Ambulatory Medical Care Survey (NAMCS) for psoriasis visits. The NAMCS is an annual, national sample of ambulatory
visits made to physicians in the US who are non-federally employed. It is conducted by the Centers for Disease Control and Prevention, National Center for Health Statistics. Data are collected using a three-staged sample design consisting of sampling geographic areas, then physicians, and finally visits
to that physician’s office for a random week. For sampled visits, medical records are used to abstract the data, either by the physician, the physician’s staff, or Census Bureau field staff. Information regarding patient demographics, diagnoses made by the physician (up to three), medications prescribed, and physician specialty, along with other visit characteristics are collected during data abstraction. Diagnoses were classified with the International Classification of Disease, 9th Revision, Clinical Modifications (ICD-9-CM).
In this study, sampled visits between 1997 and 2010 with a sole diagnosis of psoriasis (ICD-9-CM: 696.1) were included. There were 545 records meeting these criteria. We analyzed medi-
