Dr Riadh Dawood describes how psoriasis can be managed with a range of treatments including topical, ultraviolet, systemic, and biological therapies

  • Psoriasis is a disease that causes significant impairment to quality of life
  • Chronic plaque psoriasis is the most common type of psoriasis, affecting 80% to 90% of individuals with the condition
  • Management should take into account patient characteristics
  • Topical treatments for psoriasis include:
    • emollients
    • vitamin D analogues
    • tar preparations
    • dithranol
    • retinoids
    • corticosteroids
  • Although some patients with psoriasis can be managed in primary care, other individuals will need to be seen in secondary care for specialised treatments
  • Second-line treatment options for psoriasis include:
    • ultraviolet therapy
    • methotrexate
    • acitretin
    • ciclosporin
  • Patients may be eligible for treatment with biological agents if they have severe psoriasis that has not responded to standard topical and systemic therapies, and fulfil the criteria specified by NICE. These agents include adalimumab, etanercept, infliximab, and ustekinumab.

Psoriasis is a common skin disease affecting 2% of the population. It is a persistent, relapsing condition causing significant impairment to the patient's quality of life. Psoriasis can develop at any age but more commonly occurs between 15 and 30 years or after the age of 40 years. Both sexes are affected equally and there is a positive family history in some patients.1 Psoriasis can be associated with seronegative psoriatic arthritis and inflammatory bowel disease. Excessive alcohol and many drugs can precipitate psoriasis including beta blockers, chloroquine, non-steroidal anti-inflammatory drugs, and lithium.2

Types of psoriasis

There are several types of psoriasis, including:

  • chronic plaque
  • palmo-plantar (pustular or hyperkeratotic)
  • nail
  • guttate
  • erythrodermic
  • generalised pustular psoriasis
  • psoriatic arthropathy.

Chronic plaque psoriasis is the most common type with around 80%–90% of patients with psoriasis being affected.1 It encompasses scalp, flexural, and facial psoriasis, which may co-exist with seborrhoeic dermatitis (so-called sebopsoriasis).

Initial presentation

Most cases of psoriasis are mild and hence they can be treated in general practice either by the GP or GP with a Special Interest (GPwSI). Unfortunately, there is no cure for psoriasis but there are effective suppressive treatments aimed at inducing a remission or controlling the symptoms.3

Watchful waiting or no active treatment may be instigated for patients with mild longstanding disease who have accepted their condition. Treatment depends on individual patient characteristics, such as:

  • age
  • sex
  • occupation
  • general health
  • social status (e.g. does patient live alone or are they supported by a carer or a family?)
  • psychological impact of the disease
  • severity of the disease
  • location of affected body sites
  • any previous treatments.

The Psoriasis Area and Severity Index (PASI) is a measure of disease severity in chronic plaque psoriasis. A PASI score of ?10 (range 0–72) has been shown to correlate with a number of indicators commonly associated with severe disease (e.g. need for hospital admission or use of systemic therapy). The Dermatology Life Quality Index (DLQI) is a validated tool for measuring quality of life across all skin diseases. A score of >10 (range 0–30) has been shown to correlate with at least 'a very large effect' on an individual's quality of life.4

Initial treatment

The British Association of Dermatologists (BAD) and the Primary Care Dermatology Society (PCDS) guideline on the management of psoriasis recommends that patients are given both verbal and written information on treatment options. The clinician and patient should make a joint decision about the various therapeutic options, with particular attention being given to the effect of psoriasis on quality of life and the benefits and risks of treatment.3 The healthcare professional should give the patient practical demonstrations on how to apply topical treatment.3

Emollients
Almost all patients with psoriasis will need emollients and bath additives. These includes aqueous cream, emulsifying ointment, and white soft paraffin, along with many other products.2,5,6

Vitamin D analogues (calcipotriol, calcitriol, and tacalcitol)
Vitamin D analogues can be used for most types of psoriasis. They are cosmetically acceptable to the patient but they can take up to 6–8 weeks to work. They can also irritate the skin (particularly calcipotriol) especially on the face and flexural areas.2

Systemic adverse effects are rare and include hypercalcaemia and parathyroid hormone suppression. These have been reported only in people using more than 100 g per week (greater than the recommended dose).2 Neither calcitriol nor tacalcitol are licensed for used in children aged under 12 years. The use of vitamin D analogues in pregnancy and breast feeding is best avoided if possible.

Tar preparations
Tar-based preparations are a therapeutic option and are particularly suited to the treatment of scalp psoriasis;3 however they are smelly and can stain clothes. The choice of tar preparation should take into account the location of the affected skin, previous response to other treatments, and the patient's preference. Tar products can be used alone or in combination with salicylic acid, dithranol, or sulphur.

Dithranol
Dithranol is generally only used for plaque psoriasis and in patients who have psoriasis that is resistant to other topical treatments. However, the use of these preparations requires strong motivation on the part of the patient because of staining and skin irritation. Dithranol is usually used as a short-contact treatment (30–60 minutes);2–4 however, it can be difficult to apply to multiple small lesions. Dithranol comes in concentrations from 0.1% to 3% and can be very effective in a motivated patient. One effective treatment is Lassar's paste—dithranol with zinc oxide—which is applied to the plaque, covered by stockinette, and left on for 24 hours.

Retinoids
Tazarotene gel (0.05–0.1%) is a treatment option for plaque psoriasis. This therapy is teratogenic and should not be used in pregnant women and should be avoided in women who are planning a pregnancy, those who are breast feeding, and patients under the age of 18 years.5 Tazarotene can cause irritation so patients need to avoid intense sunlight and wash their hands after use.

Topical corticosteroids
Steroids are an acceptable and effective way of treating psoriasis but they carry risks with prolonged use such as skin thinning, telangiectasia, hypopigmentation, and, in rare cases, systemic absorption; in addition, flare up can occur with sudden withdrawal of the steroid.2,3

Topical corticosteroids are available in four potencies:

  • Mild (e.g. hydrocortisone)
  • Moderate (e.g. clobetasone butyrate)
  • Potent (e.g. betamethasone dipropionate, fluocinolone, mometasone)
  • Very potent (e.g. clobetasol propionate, diflucortolone valerate).

Only mild topical steroids such as hydrocortisone 1% should be used in children and on the face and flexural areas.3 For very thick plaques or on certain areas like the scalp, palms, and soles, a stronger topical steroid is needed (e.g. diflucortolone). Steroids can be used alone or in combination with an antifungal/antibacterial or a keratolytic agent, such as salicylic acid or calcipotriol.

Second-line treatment

Many patients with psoriasis are seen and followed up in primary care clinics by the GPwSI but some are triaged or referred to secondary hospital outpatient care, particularly if they require phototherapy or systemic therapy, such as methotrexate, acitretin, or ciclosporin. This is often true of patients with severe psoriasis, those unable to use other treatments, and individuals with generalised pustular or erythrodermic psoriasis.

Phototherapy
A consultant dermatologist will usually supervise the use of ultraviolet phototherapy in the management of psoriasis. It is an effective treatment for guttate or plaque psoriasis resistant to topical therapy.3

There are two types of ultraviolet phototherapy:

 

  • Ultraviolet A:7

     

    • used in combination with oral psoralen (PUVA), which is given 2 hours before treatment
  • Ultraviolet B:8

     

    • broadband ultraviolet B (BB?UVB) with a wavelength of 290–320 nm
    • narrowband ultraviolet B (NB?UVB) of 311–313 nm.

Ultraviolet treatments are usually given two to five times a week. The main risk of using phototherapy is the development of non-melanoma skin cancers.7

Systemic therapy
Patients considered for systemic therapy will usually conform to the rule of tens whereby the body surface area affected is >10%, or the PASI score is >10, or the DLQI is >10.9 The treatment is associated with significant short- and long-term side?effects, and is therefore usually initiated and followed up in secondary care in most cases. The therapeutic effect of methotrexate in psoriasis is likely to be a result of its effectson the immune system.10 Methotrexate is taken in tablet form once a week and folic acid is frequently recommended as a vitamin supplement if the patient is taking this therapy. Methotrexate is teratogenic and is contraindicated in pregnant women or those of childbearing age without adequate contraception. In addition it should be avoided in patients with severe renal failure, liver diseases, infectious diseases, or severe anaemia. Patients receiving methotrexate treatment need to have regular blood tests.11

Treatment with acitretin is effective as monotherapy or in combination with PUVA (RePUVA). However, side-effects include dryness of the mouth, lips, and eyes, and its use can lead to blood and bone abnormalities and hypertriglyceridaemia. Acitretin is not normally given to women of childbearing age.12

Ciclosporin is a drug that suppresses the immune system. It is usually taken in capsule form twice daily. The main side-effects are hypertension, renal impairment, and increased risk of malignancies. Patients taking ciclosporin should have regular blood and urine tests, along with blood-pressure measurements.13

Biological drugs

The use of biological interventions in psoriasis has been covered in a guideline by BAD;4 and NICE has issued a number of technology appraisals on the use of specific biological agents to treat this condition. Technology appraisals have been published for:14–17

  • adalimumab
  • etanercept
  • infliximab
  • ustekinumab.

Both BAD and NICE recommend that biological drugs are only to be used if the psoriasis has failed to respond to or if the patient is intolerant to conventional therapy (including systemic therapy and phototherapy) and when severe psoriasis is affecting quality of life (based on either the PASI or DLQI). Treatment continuation should be dependent on response within a certain time period.4,14–17 Biological agents do have a cost impact and their side-effects are not well known. It is important to ensure that all patients are registered with the British Association of Dermatologists Biologic Interventions Register, which will assess safety issues in the relevant population.

Referral for further care

In our locality, most referrals to dermatology services are triaged by an experienced GP with a Special Interest (GPwSI) through the Choose and Book system. The GP should consider referring the patient to secondary care in these situations: Diagnostic uncertainty

  • Failure of topical therapy
  • Extensive disease
  • Psoriasis covering more than 30%–40% of the body surface
  • Severe psychological or social impact or impact on quality of life
  • Acute unstable psoriasis (urgent referral) and erythrodermic or generalised pustular psoriasis (emergency referral).

Patient information

Healthcare professionals may find it useful to provide patients with information on support groups such as:

  • The Psoriasis Association
    7 Milton Street
    Northampton NN2 7JG
    www.psoriasis-association.org.uk
    08456 760076 or 01604 251620
  • Psoriasis and Psoriatic Arthritis Alliance
    PO Box 111
    St Albans
    Herts AL2 3JQ
    www.papaa.org
    01923 672837.

Implementation challenges

Management of psoriasis in primary care is variable—diagnosis is usually delayed and most patients are treated as having eczema. Some patients are referred to secondary care after diagnosis, while many can be treated in primary care particularly with the emergence of GPwSI services.

Patients with psoriasis usually need several topical therapies, which can be expensive. Patients can save money with a pre-payment certificate: in England, a 3 month pre-payment certificate costs £27.85 and a 12 month pre-payment certificate costs £102.50. Patients may also be prescribed insufficient quantities of medication from the GP. An additional problem is that many medications tend to disappear from the market every now and then, which can make treatment very difficult. In secondary care, there is a shortage of phototherapy machines, which can result in a prolonged wait for appropriate treatment.

Conclusion

Psoriasis is common in general practice and most cases should be diagnosed and treated in the community with the aid of GPwSIs who are in the best position to provide a holistic approach to the patient. A shared-care approach is the best way forward for individuals who are not suitable for management in primary care.

  • Psoriasis is a common disease and most cases can be managed in primary care
  • There is no mandatory tariff for dermatology outpatient services so commissioners can negotiate local tariff prices for nurse or medical time from hospitals as well as community providers
  • Commissioners will need to consider special services for patients with more severe psoriasis who need biological therapies and extensive follow up
  • The cost of biological drugs is considerable and lies outside the payment by results tariff
  • Commissioners should use contracts to ensure that biological drugs are used in line with relevant NICE Technology Appraisals and they should provide adequate funding streams for this purpose (funding to support NICE Technology Appraisals is mandatory for PCTs)
  • Tariff prices:a
    • phototherapy outpatient = £118 (JC29Z)
    • skin therapies outpatient = £138 (JC14Z).
  1. Meier M, Sheth P. Clinical spectrum and severity of psoriasis. Current Problems in Dermatol 2009; 38: 1–20.
  2. NHS Clinical Knowledge Summaries website. Psoriasis. www.cks.nhs.uk/psoriasis/management/scenario_diagnosis/diagnosis/pustular_psoriasis#-406348 (accessed 23 November 2010).
  3. British Association of Dermatologists, Primary Care Dermatology Society. Recommendations for the initial management of psoriasis. Guidelines—summarising clinical guidelines for primary care. 42nd ed. Berkhamsted: MGP Ltd, October 2010. pp 395–397.
  4. Smith C, Anstey A, Barker J et al. British Association of Dermatologists' guidelines for biologic interventions for psoriasis 2009. Br J Dermatol 2009; 161 (5): 987–1019.
  5. The British Association of Dermatologists website. Psoriasis—an overview. www.bad.org.uk/site/864/Default.aspx (accessed 23 November 2010).
  6. Mason J, Mason A, Cork M. Topical preparations for the treatment of psoriasis: a systematic review. Br J Dermatol 2002; 146 (3): 351–364.
  7. The British Association of Dermatologists website. Phototherapy. www.bad.org.uk/site/1223/default.aspx (accessed 24 November 2010).
  8. British Photodermatology Group. British Photodermatology Group guidelines for PUVA. Br J Dermatol 1994; 130: 246–255.
  9. Finlay A. Current severe psoriasis and the rule of tens. Br J Dermatol 2005; 152 (5): 861–867.
  10. Griffiths C, Clark C, Chalmers R et al. A systematic review of treatments for severe psoriasis. Health Technol Assess 2000; 4 (40): 1–125.
  11. The British Association of Dermatologists website. Methotrexate. www.bad.org.uk/site/844/Default.aspx (accessed 24 November 2010).
  12. The British Association of Dermatologists website. Acitretin. www.bad.org.uk/site/1383/Default.aspx (accessed 24 November 2010).
  13. The British Association of Dermatologists website. Ciclosporin. www.bad.org.uk/site/732/default.aspx (accessed 24 November 2010).
  14. National Institute for Health and Care Excellence. Infliximab for the treatment of psoriasis. Technology Appraisal 134. London: NICE, 2008. Available at: www.nice.org.uk/guidance/TA134
  15. National Institute for Health and Care Excellence. Etanercept and efalizumab for the treatment of adults with psoriasis. Technology Appraisal 103. London: NICE, 2006. Available at: www.nice.org.uk/guidance/TA103
  16. National Institute for Health and Care Excellence. Adalimumab for the treatment of psoriasis. Technology Appraisal 146. London: NICE, 2008. Available at: www.nice.org.uk/guidance/TA146
  17. National Institute for Health and Care Excellence. Ustekinumab for the treatment of adults with moderate to severe psoriasis. Technology Appraisal 180. London: NICE, 2009. Available at: www.nice.org.uk/guidance/TA180G