In a multi-centre European study, it was found that nearly 78% of the 330 people in the study found that scaling was a problem related to their condition (de Korte
et al., 2005). As has already been described, psoriatic plaques are characterised by over production of keratinocytes which are shed from the skin in noticeable clumps. This will often limit a person’s life in that they restrict activities due to the embarrassment of the ‘snowstorm’ they create. This may be about restricting the colour of clothing chosen so that white skin scales do not show up against dark coloured clothing, or it may be about limiting holiday choices by not staying in a hotel because of all the skin cells left in sheets or on the floor. In a small unpublished study (Ersser
et al., 2000) in which patients were asked to describe how they felt about their psoriasis, one person described it thus:
It is extraordinary how much skin is being produced. When it is like that I mean I think one can get into a mindset of being sort of revolted with one’s own body. At home if I’m the last to bed, I get up and there’s flakes all over the settee … I brush it on the floor and then get a hoover so that when people come down in the morning they are not confronted with it. (p. 8)
Related to scaling is the thickness or induration of the plaque. Whilst this symptom seems to be of less importance to the patient than scaling, it is important as a measure of treatment success. A plaque that is resolving becomes flat so that when a finger is run over it there is no change in texture between the normal skin and the plaque. Psoriasis tends to clear from the centre of the plaque outwards, so the patient will not see the plaque decrease in size, instead it will become flat in the middle with an ever decreasing ring around the edge. It is important to feel the skin when looking to see if the plaques are resolving as a plaque coloured mark will remain on the skin for around 2 weeks after the plaque flattens. This is because it takes that time for the superficial blood supply to return to normal (see later for further details).
