Ultraviolet Phototherapy Management of Moderate-to-Severe Plaque Psoriasis: An Evidence-Based Analysis

The purpose of this evidence based analysis was to determine the effectiveness and safety of ultraviolet phototherapy for moderate-to-severe plaque psoriasis.

The specific research questions for the evidence review were as follows: What is the safety of ultraviolet phototherapy for moderate-to-severe plaque psoriasis?What is the effectiveness of ultraviolet phototherapy for moderate-to-severe plaque psoriasis?

TARGET POPULATION AND CONDITION Psoriasis is a common chronic, systemic inflammatory disease affecting the skin, nails and occasionally the joints and has a lifelong waning and waxing course. It has a worldwide occurrence with a prevalence of at least 2% of the general population, making it one of the most common systemic inflammatory diseases. The immune-mediated disease has several clinical presentations with the most common (85% - 90%) being plaque psoriasis. Characteristic features of psoriasis include scaling, redness, and elevation of the skin. Patients with psoriasis may also present with a range of disabling symptoms such as pruritus (itching), pain, bleeding, or burning associated with plaque lesions and up to 30% are classified as having moderate-to-severe disease. Further, some psoriasis patients can be complex medical cases in which diabetes, inflammatory bowel disease, and hypertension are more likely to be present than in control populations and 10% also suffer from arthritis (psoriatic arthritis). The etiology of psoriasis is unknown but is thought to result from complex interactions between the environment and predisposing genes. Management of psoriasis is related to the extent of the skin involvement, although its presence on the hands, feet, face or genitalia can present challenges. Moderate-to-severe psoriasis is managed by phototherapy and a range of systemic agents including traditional immunosuppressants such as methotrexate and cyclospsorin. Treatment with modern immunosuppressant agents known as biologicals, which more specifically target the immune defects of the disease, is usually reserved for patients with contraindications and those failing or unresponsive to treatments with traditional immunosuppressants or phototherapy. Treatment plans are based on a long-term approach to managing the disease, patient's expectations, individual responses and risk of complications. The treatment goals are several fold but primarily to: 1) improve physical signs and secondary psychological effects,2) reduce inflammation and control skin shedding,3) control physical signs as long as possible, and to4) avoid factors that can aggravate the condition.Approaches are generally individualized because of the variable presentation, quality of life implications, co-existent medical conditions, and triggering factors (e.g. stress, infections and medications). Individual responses and commitments to therapy also present possible limitations. PHOTOTHERAPY: Ultraviolet phototherapy units have been licensed since February 1993 as a class 2 device in Canada. Units are available as hand held devices, hand and foot devices, full-body panel, and booth styles for institutional and home use. Units are also available with a range of ultraviolet A, broad and narrow band ultraviolet B (BB-UVB and NB-UVB) lamps. After establishing appropriate ultraviolet doses, three-times weekly treatment schedules for 20 to 25 treatments are generally needed to control symptoms.

The literature search strategy employed keywords and subject headings to capture the concepts of 1) phototherapy and 2) psoriasis. The search involved runs in the following databases: Ovid MEDLINE (1996 to March Week 3 2009), OVID MEDLINE In-Process and Other Non-Indexed Citations, EMBASE (1980 to 2009 Week 13), the Wiley Cochrane Library, and the Centre for Reviews and Dissemination/International Agency for Health Technology Assessment. Parallel search strategies were developed for the remaining databases. Search results were limited to human and English-language published between January 1999 and March 31, 2009. Search alerts were generated and reviewed for relevant literature up until May 31, 2009. Inclusion CriteriaExclusion CriteriaEnglish language reports and human studiesUltraviolet phototherapy interventions for plaque-type psoriasisReports involving efficacy and/or safety outcome studiesOriginal reports with defined study methodologyStandardized measurements on outcome events such as technical success, safety, effectiveness, durability, quality of life or patient satisfactionNon-systematic reviews, letters, comments and editorialsRandomized trials involving side-to-side or half body comparisonsRandomized trials not involving ultraviolet phototherapy intervention for plaque-type psoriasisTrials involving dosing studies, pilot feasibility studies or lacking control groups

A 2000 health technology evidence report on the overall management of psoriasis by The National Institute Health Research (NIHR) Health Technology Assessment Program of the UK was identified in the MAS evidence-based review. The report included 109 RCT studies published between 1966 and June 1999 involving four major treatment approaches - 51 on phototherapy, 32 on oral retinoids, 18 on cyclosporin and five on fumarates.. The absence of RCTs on methotrexate was noted as original studies with this agent had been performed prior to 1966. Of the 51 RCT studies involving phototherapy, 22 involved UVA, 21 involved UVB, five involved both UVA and UVB and three involved natural light as a source of UV. The RCT studies included comparisons of treatment schedules, ultraviolet source, addition of adjuvant therapies, and comparisons between phototherapy and topical treatment schedules. Because of heterogeneity, no synthesis or meta-analysis could be performed. Overall, the reviewers concluded that the efficacy of only five therapies could be supported from the RCT-based evidence review: photochemotherapy or phototherapy, cyclosporin, systemic retinoids, combination topical vitamin D(3) analogues (calcipotriol) and corticosteroids in combination with phototherapy and fumarates. Although there was no RCT evidence supporting methotrexate, it's efficacy for psoriasis is well known and it continues to be a treatment mainstay. The conclusion of the NIHR evidence review was that both photochemotherapy and phototherapy were effective treatments for clearing psoriasis, although their comparative effectiveness was unknown. Despite the conclusions on efficacy, a number of issues were identified in the evidence review and several areas for future research were discussed to address these limitations. Trials focusing on comparative effectiveness, either between ultraviolet sources or between classes of treatment such as methotrexate versus phototherapy, were recommended to refine treatment algorithms. The need for better assessment of cost-effectiveness of therapies to consider systemic drug costs and costs of surveillance, as well as drug efficacy, were also noted. Overall, the authors concluded that phototherapy and photochemotherapy had important roles in psoriasis management and were standard therapeutic options for psoriasis offered in dermatology practices. The MAS evidence-based review focusing on the RCT trial evidence for ultraviolet phototherapy management of moderate-to-severe plaque psoriasis was performed as an update to the NIHR 2000 systemic review on treatments for severe psoriasis. In this review, an additional 26 RCT reports examining phototherapy or photochemotherapy for psoriasis were identified. Among the studies were two RCTs comparing ultraviolet wavelength sources, five RCTs comparing different forms of phototherapy, four RCTs combining phototherapy with prior spa saline bathing, nine RCTs combining phototherapy with topical agents, two RCTs combining phototherapy with the systemic immunosuppressive agents methotrexate or alefacept, one RCT comparing phototherapy with an additional light source (the excimer laser), and one comparing a combination therapy with phototherapy and psychological intervention involving simultaneous audiotape sessions on mindfulness and stress reduction. Two trials also examined the effect of treatment setting on effectiveness of phototherapy, one on inpatient versus outpatient therapy and one on outpatient clinic versus home-based phototherapy.

The conclusions of the MAS evidence-based review are outlined in Table ES1. In summary, phototherapy provides good control of clinical symptoms in the short term for patients with moderate-to-severe plaque-type psoriasis that have failed or are unresponsive to management with topical agents. However, many of the evidence gaps identified in the NIHR 2000 evidence review on psoriasis management persisted. In particular, the lack of evidence on the comparative effectiveness and/or cost-effectiveness between the major treatment options for moderate-to-severe psoriasis remained. The evidence on effectiveness and safety of longer term strategies for disease management has also not been addressed. Evidence for the safety, effectiveness, or cost-effectiveness of phototherapy delivered in various settings is emerging but is limited. In addition, because all available treatments for psoriasis - a disease with a high prevalence, chronicity, and cost - are palliative rather than curative, strategies for disease control and improvements in self-efficacy employed in other chronic disease management strategies should be investigated. (ABSTRACT TRUNCATED)