PSORIASIS ASSOCIATION RESEARCH REPORT

Title of the research project
The effects of psychological distress on the efficacy of psoralen and ultraviolet A irradiation therapy in psoriasis patients

Grant Awarded £15,146

Locations of the research
Hope Hospital, Salford and City of Dublin Skin and Cancer Hospital

Lead investigator Professor Christopher Griffiths, Hope Hospital, Salford

Reasons for doing the research
To see if being a high-level worrier makes any difference to the way that people with psoriasis respond to treatment with photochemotherapy.

Type of research
A clinical study of 122 patients with chronic plaque psoriasis.

Date grant awarded 1999

Date research published 2003

Outcomes of the research
Those people who were classified as high-level worriers (using the Penn State Worry Questionnaire) were found to be slower at responding to photochemotherapy than those who were low-level worriers. On one measure, low-level worriers took about 80 days for their psoriasis to clear, whilst high-level worriers took almost 100 days. Levels of worry did not seem to be related to age, duration of psoriasis, age that the psoriasis first appeared, weekly alcohol intake or severity of psoriasis. There were more high-level worriers from families where first-degree family members also had psoriasis.

Conclusions
Psychological processes like worry may have a significant role to play in how quickly someone responds to treatment for their psoriasis, and this should be recognised when designing treatment regimes.

What does this project mean for people with psoriasis?
Treatments for psoriasis are well known to take some time before they show an effect. The research suggests that this period tends to be prolonged in people who are high-level worriers. The result of this may be that people give up on treatment earlier than they should, as high-worry levels have a prolonged response time. High-level worriers may therefore benefit from some sort of psychological intervention (for example, cognitive behavioural therapy) before the start of their treatment, in order to reduce worry levels and make response to treatment quicker.
Professor Chris Griffiths says ”The funding from the Psoriasis Association was extremely helpful in supporting our early research into the brain-skin axis as it pertains to psoriasis”.

Have there been any publications as a result of the research?
Yes. A publication directly related to the above research was published in Archives of Dermatology and a subsequent related study was published in the British Journal of Dermatology. The centre which carried out this research has gone on to become a leader in the field of investigating the links between brain and skin.

Glossary
Cognitive behavioural therapy: A form of talking therapy based on modifying thoughts, assumptions, beliefs and behaviours, with the aim of influencing disturbed emotions
Penn State Worry Questionnaire (PSWQ): This is a 16-item scale that has been shown to be a reliable measure of pathological worry. Worry is a normal phenomenon, but there is evidence that pathological worrying may be different from normal worrying. A PSQW score of greater than 60 (where 80 is the maximum possible) is accepted as indicating ‘high-level worry’.
Photochemotherapy: This is light therapy using ultraviolet light A (UVA) in combination with a drug called 8-methoxypsoralen, which is taken by mouth. The drug makes skin more sensitive to UVA.