Comparing therapy costs for physician treatment of warts

Journal of Drugs in Dermatology, Dec, 2003 by Robert J Clemons, Annette Clemons-Miller, Sandra Marchese Johnson, Susan K Williamson, Thomas D Horn

Abstract

To compare the cost of several common modalities used to treat non-genital warts in immunocompetent patients, we identified studies published in English using standard search strategies and evaluated the literature for the following common non-genital wart therapies: cryotherapy with liquid nitrogen, carbon dioxide and pulsed-dye laser therapy, topical squaric acid, intralesional bleomycin, intralesional interferon alpha injections, and intralesional immunotherapy with Candidu antigens. Standard treatment algorithms, compiled by dermatologists experienced in the treatment of patients with moderate wart burdens, were utilized for cost-comparison analyses.

Based on the cost analysis model, the least expensive treatment option for non genital warts were carbon dioxide laser therapy ($157) and Candida antigen injections ($190). The other treatment modalities examined ranged from $495 (bleomycin) to $1227 (interferon alpha). Although treatment with the carbon dioxide laser therapy is the least expensive, pain and post-procedure complications limit the use of this modality.

Introduction

Verrucae or warts are benign epidermal tumors caused by the human papillomavirus (HPV). Non-genital warts in the immunocompetent patient are seldom more than a cosmetic disturbance, while the immunosuppressed patient may develop widely disseminated disease with the possible progression of individual verrucae to squamous cell carcinoma (1). The incidence of verrucae is staggering. In 1990, there was an estimated 79% lifetime risk of acquiring HPV with an annual incidence of 8% (2). A study of Australian schools showed that 22% of children have warts (3).

There are several options to consider for the in office treatment of non-genital warts when home therapies such as salicylic acid have failed. We chose to compare cryotherapy with liquid nitrogen, intralesional bleomycin, carbon dioxide and pulsed-dye laser therapy, topical squaric acid, intralesional interferon alpha injections, and intralesional immunotherapy with Candida antigens. Our goal was to evaluate which therapy was the most cost effective, especially important in this age of cost containment.

Methods

Addressing the issue of cost analysis for the treatment of non genital warts involved establishing the typical frequency and duration of treatment courses and obtaining a set of physician fee schedules and average wholesale costs for each of the following wart therapies: cryotherapy with liquid nitrogen, carbon dioxide and pulsed-dye laser treatment, intralesional interferon alpha, topical squaric acid, intralesional bleomycin, and Candida antigen injections. We decided to narrow our cost analysis to patients with moderate wart burdens and so arbitrarily determined that five non-genital warts on a hypothetical patient would be treated. Based on textbook guidelines, we assumed each wart to be 5 millimeters in diameter, which is considered to be the average size of an individual wart (4). In order to establish the average number of treatments required for wart clearance, a review of the literature was conducted in which the studies were categorized by treatment method, treatment schedule, and average number of treatments required for wart clearance. A thorough review of Medline from January 1, 1966 to April 1, 2002 was performed looking for studies that evaluated each of the seven treatment modalities (Table l). The search strategy employed utilized the MeSH terms and/or key words listed in Table 2. Articles were included in the study if they had greater than 20 patients, treated non-genital warts, and specified the treatment schedule or gave an average number of treatments. Studies that included immunosuppressed patients were not included in the literature review. Time to wart clearance was defined as the time required to achieve complete wart resolution. This study does not take into consideration recurrence rates, however, as several reports did not include these data.

To determine the charges for the physician services, we selected five-digit procedural codes from me American Medical Associations (AMA) physician's Current Procedural Terminology (CPT) Fourth Edition 2001 (17). The selection methods for the codes were based upon the AMA CPT 2001 coding guidelines. The AMA CPT 2001 is separated by categories such as evaluation and management, anesthesia, surgery, radiology, pathology, and medicine. We used codes from the evaluation and management and surgery sections (Table 3). For simplicity, we chose to use only the Arkansas Medicare non-facility fee schedule for the CPT codes; however, we realize that these costs may vary in other locations. The non-facility fee, which is used for private practice clinics, differs from facility (academic center) fees.

Medicare takes into account that private practice clinics pay for their own overhead and therefore provides a higher payment to assist in these costs. The average wholesale costs of medications for the treatment modalities reviewed were obtained from the 2001 Drug Topics Red Book (18) (Table 4).