Patterns of Vitamin D Analog Use for the Treatment of Psoriasis

August 2013 | Volume 12 | Issue 8 | Original Article | 906 | Copyright © August 2013


Christine S. Ahn BA,a Farah Awadalla MD,e Karen E. Huang MS,a Brad Yentzer MD,a
Tushar S. Dabade MD,a,d and Steven R. Feldman MD PhDa,b,c

aWake Forest School of Medicine, Center for Dermatology Research, Department of Dermatology, Winston-Salem, NC
bWake Forest School of Medicine, Department of Pathology, Winston-Salem, NC
cWake Forest School of Medicine, Center for Dermatology Research, Department of Public Health Sciences, Winston-Salem, NC
dTufts Medical Center, Department of Dermatology, Boston, MA
eDermSurgery Associates, Houston, TX

Abstract
BACKGROUND: Psoriasis is a chronic disease that significantly impacts patients’ quality of life. It most commonly manifests as localized disease, for which there are various treatment options.
OBJECTIVE: To determine the prescription patterns of topical corticosteroids and vitamin D analogs for the treatment of psoriasis in the United States and how their use has changed over time.
METHODS: Data from the National Ambulatory Medical Care Survey (NAMCS) from 1994 to 2010 were queried for visits linked with a psoriasis diagnosis. Prescriptions for topical corticosteroids and vitamin D analogs were described. Vitamin D analogs usage was compared across physician specialties. For each sampled visit reported in the NAMCS, visits meeting our inclusion criteria that also mentioned the following medications were identified: topical calcipotriene, topical calcipotriene/betamethasone or any topical corticosteroid indicated for the treatment of psoriasis.
RESULTS: There were an estimated 2.05 million psoriasis visits per year over the 1994-2010 interval. Dermatologists were responsible for 67% of these encounters followed by family practice (14%) and internal medicine (11%). Dermatologists prescribed a vitamin D product at 15% of psoriasis visits, followed by family physicians at 12%, and internists at 5%. Dermatologists prescribed calcipotriene, calcipotriene/betamethasone, and topical corticosteroids in 15%, 4% and 59% of psoriasis visits, respectively. Over time, there was no significant change in the use of topical steroids or vitamin D products by physicians.This study is limited by the inability to determine the severity of psoriasis from the data collected, and the lack of data on the length of treatment with different medications.
CONCLUSIONS: Despite their demonstrated efficacy and safer side effect profile, vitamin D analogs are used less often than topical corticosteroids for the treatment of psoriasis. These findings suggest that vitamin D products may not be utilized to their fullest potential as effective topical therapy or adjuncts to therapy for localized plaque psoriasis.

J Drugs Dermatol. 2013;12(8):906-910.

INTRODUCTION

Psoriasis is a chronic, immunologic disease that affects up to 4% of the population.1 The majority of individuals diagnosed with psoriasis have mild or localized disease, affecting less than 3% of body surface area.1 Although localized disease is amenable to treatment with topical therapies, the treatment of psoriasis is challenging due to the chronicity and heterogeneity of the disease, variable response to treatment, and adverse effects of long-term medication use.
The armamentarium of treatment options available to patients with psoriasis has evolved over time. Topical agents that are used for localized or milder forms of disease, include cholecalciferol (vitamin D3) analogs or metabolites, corticosteroids, retinoids, dithranol, and coal tar preparations. Phototherapy with psoralen ultraviolet A (PUVA) or ultraviolet B (UVB) is often used as an adjunct treatment for moderate psoriasis, and for moderate-to-severe or extensive disease, options for systemic treatment include cyclosporine, methotrexate, retinoids such as etretinate and acitretin, and the newer immunomodulators, or biologic agents.2
Among the topical treatments for psoriasis, potent corticosteroids such as betamethasone diproprionate are a mainstay of treatment. Betamethasone dipropionate acts on the glucocorticoid receptor, suppressing inflammation, erythema, and hyperproliferation that are features typical of plaque psoriasis lesions.3 However, long-term use of potent corticosteroids is associated with localized cutaneous reactions such as skin atrophy, striae, telangiectasias, and cutaneous infection. Systemic adverse effects occur through absorption from the skin, and may infrequently lead to suppression of the hypothalamus-pituitary axis.4 In 1994, a topical vitamin D analog, calcipotriene, was introduced in the United States as a treatment for mild plaque psoriasis.5 Vitamin D analogs exert their effect through a different mechanism; they bind to the vitamin D3 receptor, inhibiting cell proliferation and increasing cell differentiation.2
Clinically, calcipotriol is well-tolerated and effective in the treatment of psoriasis.3 In a systematic review, calcipotriol was more effective than traditional topical treatments such as dithranol