Open Journal Systems

ORIGINAL CONTRIBUTIONS

Received: March 3^rd 2015

Judged: April 28^th 2015

From evidence to expertise: concordance in the topical management of psoriasis

Fermín Jurado-Santa Cruz,^a Francisco Páez-Agraz^b,c

^aCentro Dermatológico “Dr. Ladislao de la Pascua”, Secretaría de Salud del Distrito Federal

^bUnidad de Asesoría en Investigación, Servicios de Atención Psiquiátrica, Secretaría de Salud

^cInstituto para el Fortalecimiento de Capacidades en Salud, Focus Salud México, S.C.

Ciudad de México, México

Communication with: Fermín Jurado-Santa Cruz

Telephone: (55) 5538 4314; (55) 5538 7033; (55) 5532 5638

Email: fer_jur_sc@hotmail.com

Vulgar psoriasis is an inflammatory cutaneous-systemic disease, chronic and intermittent. Its etiology is not defined, and it has a higher risk of comorbidities which affect the patients’ quality of life. The objectives of this trial were establishing the concordance between Guía de Práctica Clínica (GPC) of the plaque psoriasis pharmacological treatment and the clinical practice of a group of Mexican dermatologists, experts in the psoriasis topical treatment; as well as weighing up the interest and knowledge of quality of life and adherence to treatment. A Delphi questionnaire was applied to 30 experts to explore their therapeutic behavior and attitudes toward the assessment of quality of life and treatment adherence. A meeting was held with a subgroup of 10 dermatologists to analyze the results. A second questionnaire was responded to distinguish the decisions taken for topical treatment in institutional and private practice, as well as other items unexplored in the first questionnaire. After analyzing the questionnaires results, it was clear that the data published in the Guía de Práctica Clínica and the prescriptive attitude of the experts are consistent with respect to the topical treatment for plaque psoriasis. There is also agreement on the attitude about drug prescriptions between the physicians in the private and institutional medical care, although in the private practice it is more common to use vitamin D analogues and corticosteroids and the salicylic acid replaces corticosteroids in the institutions.

Keywords: Psoriasis; Topical administration; Quality of life

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Psoriasis vulgaris is a systemic inflammatory cutaneous disease of chronic and intermittent evolution, completely lacking defined etiology, genetically determined, pathophysiologically autoimmune, with characteristics of an auto-inflammatory disease and with an increased risk of comorbidities that impacts patients’ quality of life. It affects people of all ages, predominantly young adults. It may be associated with other inflammatory conditions such as psoriatic arthritis, inflammatory bowel disease, and cardiovascular disease. Globally, its prevalence is estimated at 2%.¹ It is thought that approximately 2.5 million people in Mexico are affected, of which 80% have milder forms and the rest moderate to severe forms.² Psoriasis vulgaris is one of the 15 most common chronic skin diseases in Mexico.  

This disease is characterized by the presence of erythematous plaques, predominantly on bony protrusions. There are different clinical varieties that have been classified based on topography, morphology, age of onset, extent (BSA, body surface area), severity (or PASI, Psoriasis Area Severity Index), and quality of life (DLQI, Dermatology Life Quality Index).³

This dermatosis has no specific treatment, and usually requires individualization and modification according to the characteristics and clinical outcome of each case. Some history must be taken into account to define the initial approach, such as previous topical and systemic treatments, findings on physical examination, and the presence of co-morbidities; one also must determine the possible contraindications to the various treatments available. Social factors should also be taken into account, such as quality of life, cultural level, and adherence to treatment, as well as economic factors and the availability of treatments.⁴ Therapies applied to each patient may vary over time, change effectiveness, or generate intolerance or risk of toxicity, which must be evaluated by the dermatologist.⁴

The objectives of this study were to determine the correlation between the clinical practice guideline (CPG) "Medication treatment for adult patients with plaque psoriasis" published by the Centro Nacional de Excelencia Tecnológica en Salud (CENETEC),⁵ and the clinical practice of a group of Mexican dermatologists, psoriasis experts, in the topical treatment of this disease. We also sought to clarify the importance of considering the quality of life and treatment adherence in patients with this dermatosis. CPGs,⁵ as CENETEC (the institution responsible for the publication of this guide) explains, are "an element of stewardship in health care, which aims to establish a national benchmark to favor clinical and managerial decision-making based on recommendations underpinned by the best available evidence in order to contribute to the quality and effectiveness of health care."⁵

The CPG mentioned was created by development groups according to the methodology agreed upon by public institutions of Mexico’s Sistema Nacional de Salud: the Secretaría de Salud, the Instituto Mexicano del Seguro Social (IMSS), the Instituto de Seguridad y Servicios Sociales de los Trabajadores del Estado (ISSSTE), the Secretaría de Defensa Nacional (SEDENA), the Secretaría de Marina (SEMAR), the Sistema Nacional para el Desarrollo Integral de la Familia (DIF), and Petroleos Mexicanos (PEMEX).

Methodology

A summary was developed of Mexican CPGs for the topical management of psoriasis in adult patients.⁵ Later, a Delphi questionnaire was administered to a group of 30 experts to explore their topical therapeutic behavior. Then, a modified Delphi questionnaire was applied to a group of 30 experts to explore their behavior and attitudes towards assessing the quality of life and adherence of the psoriasis patient. Finally, a meeting was held with a selected subgroup of 10 dermatologists to analyze the results. A psychiatrist quality of life expert provided support. The analysis subgroup found it necessary to conduct a second Delphi survey to differentiate decision-making in the topical treatment at private and institutional levels, and to assess some other points not explored in the first survey.

Summary of Clinical Practice Guidelines

The topical treatment of psoriasis mainly uses salicylic acid, coal tar, vitamin D analogues, corticosteroids, dithranol (anthralin), calcineurin inhibitors, tazarotene, and urea.

The evidence and recommendations for use of each of these therapeutic alternatives is synthesized here according to the CPGs mentioned.⁵

Salicylic acid

Salicylic acid may be compounded in most formulations. It is suggested to use concentrations of 5 to 10% in petroleum jelly in patients with mild to moderate psoriasis. One or two applications per day should be prescribed until remission of the patient's lesions. This therapy can be combined with coal tar.

Recommendation: use with topical steroids is advised to improve the bioavailability of the latter. It is suitable to use on plaques with thick scaling.⁶ Use in the anogenital region, folds, mucous membranes, eyes, and healthy skin areas should be avoided.

Coal tar

Only six studies of more than 19 documented in the guidelines of the German Society of Dermatology met the inclusion criteria for clinical guidelines. One of them was carried out as a monotherapy, so there is insufficient evidence to determine the efficacy of monotherapy with coal tar. In combination therapy with UV radiation, a PASI of 75% was recorded in 12 out of 13 patients after 26 (+ 5.9) sessions in the study of Diette et al.⁷ It is important to consider that ultraviolet light and coal tar are considered carcinogenic.

Recommendation: use as monotherapy for the treatment of psoriasis vulgaris is not suggested. The use of coal tar in combination with UV therapy may be considered in some patients.⁸

Point of good practice: for mild to moderate psoriasis, concentrations of 5 to 10% are recommended in a vehicle such as petrolatum, for a maximum period of four weeks, reducing days of application during the maintenance phase. For hairy skin there are preparations in shampoo.⁸

Vitamin D analogues

Most available information relates to calcipotriol.

Point of good practice: calcipotriol is recommended for mild to moderate psoriasis. Two applications per day in affected areas up to 30% of body surface should be prescribed as a starting dose, not to exceed 100 grams per week up to one year. Calcitriol should be prescribed twice daily for up to 35% of body surface, for periods up to six months, with longer periods; however, there is no experience with this dermatosis in accordance with the publications reviewed.

The efficacy and tolerance of vitamin D3 analogs can improve if combined with corticosteroids in the initial therapy.⁸

The combination with potent corticosteroids appears to be superior to either agent alone. A meta-analysis of 1500 patients with psoriasis vulgaris showed a PASI reduction of about 70% at four weeks of treatment with calcipotriol at 0.05% and betamethasone dipropionate at 0.5% applied once daily. On the other hand, the addition of calcipotriol therapy with PUVA (psoralen plus ultraviolet light) can accelerate and improve the response to treatment.

Recommendation: the combination of vitamin D3 analogs and steroids is suggested as induction therapy in the first four weeks for patients with mild to moderate psoriasis.⁹

It is important to remember that the effect of calcipotriol is inhibited when combined with salicylic and lactic acid. Furthermore, ultraviolet light inhibits vitamin D derivatives, so it should be applied after irradiation and not before.⁹

Calcipotriol is a safe drug even in the pediatric population.

Corticosteroids

The use of class III topical steroids for psoriasis vulgaris with mild to moderate intensity is usually recommended.⁸ According controlled studies with adequate evidence, class I corticosteroids can achieve a 50 to 68% improvement after a treatment period of two weeks. On the other hand, according to the analysis of the results of several double-blind placebo-controlled studies, good or excellent clinical improvement was found in a percentage ranging between 41 and 72% of patients with psoriasis treated with class II-VI corticosteroids in periods of three weeks. To choose the power of the steroid, factors such as the extent of dermatoses, the topography of the lesion, and the patient's age must be taken into account.  

Low-power steroids are indicated for sites like face, intertriginous areas, and for short periods; they can also be used by children. Other topographical areas in adults can be treated from the beginning with medium- or high-power agents. In general, patients with thick and chronic plaques may require very high-power steroid treatment, although for periods not exceeding two to four weeks.⁹

The combination with salicylic acid 5% improves the therapeutic effect of steroids, since its keratolytic effect decreases scales, which favors the penetration of steroids.

Recommendation: It is advised to administer combination therapy with reducers or keratolytics to improve the effectiveness of the steroids.⁸

Topical corticosteroids can also be combined with vitamin D3 analogues. The use of betamethasone dipropionate 0.05% and calcipotriol 0.005% is suggested twice daily for one month and then administered in pulses (twice a week, every other day, or only weekends) as a maintenance phase.⁹ The combination with systemic therapies in moderate to severe psoriasis is recommended.

It is important to consider the irreversible cutaneous side effects of corticosteroids, regardless of the related effects of suppression of adrenal function. It must be remembered that tachyphylaxis may occur with long-term use, which may cause rebound phenomenon with abrupt suspension.

In most studies it is recommended to apply the drug twice a day, since increasing the frequency of application increases the improvement, but also risks side effects.⁸

Dithranol (anthralin)

Dithranol is one of the oldest treatments for psoriasis that ranges from mild to moderate. It is considered a very safe therapy, since only pigmentation disorders, burning, and erythema have been reported, but no adverse systemic effects.⁸

Some studies have obtained complete remission (100% reduction of PASI) in 30-70% of patients, and partial remission (75% reduction of PASI) in a percentage that goes from 26 to 100% of patients after a period of five to eight weeks of use.

Recommendation: to enhance the therapeutic response, combine with phototherapy or other topical preparations, for example calcipotriol.⁸ It is preferred to start with preparations at 0.5% for long-term therapy or 1% for short-term therapy, then increase according to the patient's tolerance. The expected improvement is achieved after two or three weeks of use.⁹

It is important to note that this product is not currently available in Mexico.

Calcineurin inhibitors

These inhibitors act by blocking the synthesis of various inflammatory cytokines involved in the pathogenesis of psoriasis. A randomized, double-blind study in patients with facial and intertriginous psoriasis achieved 65% improvement with the administration of tacrolimus 0.1% applied twice daily for eight weeks. The most common side effects were irritation and itching, which decreased with time of application.

A therapeutic alternative is pimecrolimus at 1% in cream twice a day, in the facial, intertriginous, and anogenital regions for eight weeks or until remission of the lesions. It is recommended as an alternative in case of facial and inverted psoriasis refractory to first choice treatment.⁹

Tazarotene

Weinstein et al. compared monotherapy tazarotene cream at 0.05% and 0.1% with a placebo; 58.8% of patients treated with tazarotene 0.1% and 47.6% with the substance at 0.05% had an improvement of more than 50% after 12 weeks of treatment.⁸ The same response was observed in 26.6% of the placebo group.⁸

Tazarotene can be considered in the treatment of mild to moderate psoriasis vulgaris.⁸ If you start with 0.05% gel in the afternoon for one or two weeks, the maintenance dose (if necessary) is done with 0.1% gel another two weeks.^8,9

The combination with topical steroids enhances its effect. The best results were obtained when combined with betamethasone dipropionate and mometasone for periods of up to 12 weeks.^8,9

Recommendation: It is suggested to combine tazarotene with topical steroids and avoid contact with healthy skin.⁸

The most common side effects of tazarotene are irritation and photosensitivity.

Urea

Urea at high concentrations (over 15%) has keratolytic properties, while at low concentrations it has moisturizing properties.

Point of Good Clinical Practice: in patients with mild to moderate psoriasis, concentrations of 10 to 40% are recommended as monotherapy or in combination with other topical treatments or in the maintenance phase.

Recommendation: It is advised to prescribe urea at concentrations higher than 15% as monotherapy or in combination with other active ingredients such as salicylic acid to enhance its keratolytic effect.⁶

Its use is limited. Some patients report itching and burning sensations when applying topical preparations combined with urea.

Figure 1 shows the algorithm for the topical treatment of plaque psoriasis found in the CENETEC guide.

Delphi survey results

A first survey was applied to the 30 dermatology specialists who care for adult patients with plaque psoriasis of mild to severe intensity. The questionnaire consisted of 14 questions and was answered by 27 experts.

Topical treatment of choice for adults

For mild psoriasis, experts showed preference for vitamin D analogues (74.1%), corticosteroids (70.4%), salicylic acid (44.4%), urea (40.7%), coal tar (18.5%), calcineurin inhibitors (14.8%), tazarotene (3.7%), and dithranol (0%).

As for moderate psoriasis, preference was found for the use of vitamin D analogues (85.2%) and corticosteroids (77.8%). Salicylic acid (48.1%) and urea (40.7%) were the treatments that followed in respondents’ preference for prescription. Coal tar (22.2%) and calcineurin inhibitors (18.5%) were the next options used by specialists. The final choices were tazarotene (14.8%) and dithranol (anthralin) (3.7%).

Regarding severe psoriasis, the first choice was vitamin D analogues (70.4%) and corticosteroids (66.7%), followed by salicylic acid (33.3%), calcineurin inhibitors (25.9%), urea (22.2%), coal tar (22.2%) and tazarotene (14.8%). The drug least used, as in the previous indications, was dithranol (3.7%).

The detailed results about the topical of choice for adults can be seen in Table I.

Topical treatment of second choice

Regarding the topical treatment of second choice for mild psoriasis, responses were distributed as follows: the most prescribed were calcineurin inhibitors (51.9%), followed by coal tar (44.4%) and tazarotene (40.7%). Less often they mentioned the use of salicylic acid (25.9%), urea (18.5%), vitamin D analogues (18.5%), and corticosteroids (14.8%). The least preferred was dithranol (anthralin) (3.7%).

As for the topical treatment of second choice for moderate plaque psoriasis in adults, experts most frequently reported coal tar (44.4%), calcineurin inhibitors (40.7%), salicylic acid (40.7%), and tazarotene (37.0%). Less frequently, respondents mentioned urea (25.9%), corticosteroids (18.5%), vitamin D analogues (14.8%), and dithranol (anthralin) (3.7%).

As topical treatment of second choice in cases of severe psoriasis, experts prescribed calcineurin inhibitors (37.0%), coal tar (37.0%), tazarotene (33.3%), and salicylic acid (30.7%). To a lesser extent they used urea (22.2%), vitamin D analogues (22.2%), and corticosteroids (18.5%). The least used was dithranol (7.4%).

All results related to the topical of second choice can be seen in Table II.

Combined treatment

The responses obtained for preferences for the combined treatment of plaque psoriasis were 70.4% as coadjuvant therapy in patients with severe psoriasis, 63.0% in moderate psoriasis, 48.1% in severe psoriasis, and 48.1% after a first attempt with monotherapy. To a lesser extent, the experts indicated a preference for combined treatment from the start in severe cases (33.3%). Only a few opinions agreed on combined treatment in cases of mild psoriasis (14.8%).

Regarding the most commonly used combination therapy, respondents reported the following results:

• Steroids + vitamin D analogue in a single product (77.8%).
• Combinations of salicylic acid (44.4%).
• Steroids + vitamin D analogue separately (18.5%).
• Another treatment (not mentioned) (7.4%).

As for the features that experts took into account to indicate the combined topical for psoriasis treatment, the results were: a) number of times per day to apply the treatment (81.5%), b) psoriasis severity (77.8%), c) duration of treatment (66.7%), d) if it was an intermittent or continuous pattern (37.0%), and e) other characteristics (3.7%).

Regarding the characteristics of topical psoriasis products, respondents said they took into account: a) their effectiveness (100%), b) safety (88.9%), c) ease of application (81.5%), d) speed of action (77.8%), e) comfort of use (70.4%), f) price (70.4%), and g) other characteristics (3.7%).

Finally, the experts’ criteria were evaluated for when they consider a patient refractory to topical treatment. The results were as follows: a) if there was no improvement response after eight weeks of treatment (74.1%); b) when there was no response to combination therapy (51.9%), c) after receiving a therapeutic regimen without response regardless of time or scheme (14.8%), d) cases that do not respond to treatment with corticosteroids (7.4%), or some other characteristic (7.4%). Additional features reported by the experts included: a) when the patient had their quality of life affected, b) when there was no improvement response after eight weeks of treatment and comorbidities were controlled, c) when the patient does not respond to different treatments according to established treatment guidelines.

Quality of Life Questionnaire

The study was complemented by a survey on the quality of life and adherence to treatment according to the group of experts who treated patients with psoriasis. 24 expert responses were collected.

The quality of life of patients with psoriasis was considered fair (45.8%) to poor (33.3%), which amounts to 79.2% of cases in the opinion of specialists. It stands out that 4.1% considered quality of life very bad.

As for the assessment of the adherence to topical treatment, the experts considered it fair in 66.7% of cases and good in only 33.3%.

Regarding the factors influencing adherence to topical treatment in patients with psoriasis, respondents indicated as the main variables the cost of treatment (33.3%) and the application more than once a day (25.0%). Table III lists the factors identified by the survey.

Regarding the factors that affected the quality of life of patients with uncomplicated psoriasis, the most important was body image (87.5%), and the persistence of disease symptoms (58.3%), depression or anxiety (58.3%),¹¹ negative effects on interpersonal relationships (58.3%),¹¹ and the perception of being stigmatized (50.0%). To a lesser extent they reported negative impact on job performance (41.7%), the myth that psoriasis is a contagious disease (4.2%), and unspecified repercussions in sexuality (4.2%).

Specialists said they routinely evaluated adherence to topical treatment of psoriasis patients (83.3%), but a low percentage indicated otherwise (16.7%). Regarding the consideration of quality of life of psoriasis patients in clinical practice, only 70.8% of the experts noted that they evaluated it routinely, while 29.2% did not take it into account on a regular basis. Among those who indicated that they evaluated the quality of life of psoriasis patients, only 25% indicated that they used an instrument to evaluate adherence to topical treatment. The best-known instrument is the medication treatment satisfaction questionnaire (33.3%). Up to 20.8% of respondents said they did not know instruments to evaluate this area, and very few indicated other specialized tools (DLQI, Skindex 16, SF-36 [with physical and mental component], PQoL psoriasis quality of life questionnaire, or PDI-12).¹² The instrument used most frequently by specialists who used any was the DLQI (70.8%).

Second survey of prescription at the institutional and private levels

A second survey was made of experts, and 21 dermatologists responded to investigate the differences in the treatment of psoriasis in private or institutional practice. Hallmarks of treatment indicated in one area or another are found, which are described below.

According to this second survey, nine of the 21 experts mentioned that they used topical treatment only in mild psoriasis; 11 out of 21 used topical treatment in moderate to severe psoriasis, and fewer (six experts) used it as an adjunct to systemic therapy.

In patients with plaque psoriasis, the experts indicated that in private clinical practice they used vitamin D analogues (79.2%) and corticosteroids (79.2%); in institutions they used more corticosteroids (66.7%) and salicylic acid (66.7%).

Regarding treatment used according to the severity of plaque psoriasis in mild, moderate, and severe forms, the preferred treatment in private practice was vitamin D analogues and corticosteroids, while in institutional practice the preference was different: in mild psoriasis, the first option was corticosteroids, secondly vitamin D analogues and salicylic acid in equal proportions; in moderate psoriasis corticosteroids were the first choice and calcineurin inhibitors as a second, and for severe psoriasis corticosteroids were chosen as first choice and coal tar as a second (Table IV). 

Experts prefer combined treatment (systemic + topical) when the patient presents with moderate and severe psoriasis. The main characteristics that the physician considers to indicate systemic + topical treatment are: the severity of psoriasis, the treatment duration, and the number of times it is applied.

Experts prefer to use combined treatment (topical + topical) when the patient presents with mild to moderate psoriasis. Furthermore, this treatment is also preferred as an adjuvant in severe psoriasis.

There are several features that the doctor considers to indicate the topical + topical treatment, such as severity, practicality, economy, the frequency of application, etc.

According to the experience of the specialists, lotion is the pharmaceutical form that produces greater adherence to treatment, followed by the presentation in gel. The selection criteria for both pharmaceutical presentations are: extension (mild, moderate, or severe), ease of application, topography, and pervasiveness.

The reasons why these differences in treatment differ between private or institutional areas derive from the objectives of this work, since further study is needed, dedicated specifically to studying the factors that influence physicians’ prescribing. However, these are important characteristics that must be taken into account when applying the CPG for psoriasis.

Conclusions

There is a clear correlation between what is published in the clinical practice guideline "Medication treatment for adult patients with plaque psoriasis" and prescriptive behavior of experts in relation to the topical treatment of plaque psoriasis. Similarly, between private and institutional practice there are points of coincidence, except that the former preferred the use of vitamin D analogues and corticosteroids, while in the latter salicylic acid replaces corticosteroids.

Experts prefer combination therapy (systemic + topical) when the patient presents with moderate and severe psoriasis. They also take into account the severity of psoriasis, the duration of treatment, and the number of times that it is applied as main features to indicate systemic + topical treatment.

The current assessment instruments for quality of life have the psychometric characteristics of feasibility, validity, reliability, and sensitivity to change. Experts know them enough, although they evaluate adherence empirically.

CPGs are based on the best available scientific evidence, so it is necessary to disseminate them among dermatology specialists and primary care staff, with the aim of standardizing actions to identify which patients should use topical and systemic therapy, to determine the dosage, and the benefits and risks that may occur with each of the therapeutic modalities, including the optimal treatment of plaque psoriasis and increased adherence, which will provide for better quality of life.

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