Hand eczema extent and morphology--association and influence on long-term prognosis.

Hand eczema extent was a strong negative prognostic factor in a previously published follow-up study of 868 individuals. The present aims were to study in the same cohort the association between the extent and the morphology of the hand eczema and to examine whether registering both improves the prediction of long-term prognosis. The cohort was divided into subgroups regarding eczema extent and morphology. An association between eczema extent and morphology was found, with a Spearman's correlation coefficient of 0.36. Thus, widespread eczema clearly tended to be polymorphic, and vice versa. More than two-thirds (68%) of the subjects with visible signs of eczema at the examination ended up in corresponding "high" or "low" subgroups according to extent and morphology. Both widespread eczema and polymorphism were negative prognostic factors, but recording morphology did not significantly add any information to the long-term prognosis for the groups with high or low extent scores. In conclusion, the results show a clear association between extent and morphology of hand eczema, both predicting prognosis. Recording morphology did not add significant information when assessing long-term prognosis. Consequently, our study indicates that preference should be given to uncomplicated assessment of eczema extent in studies on hand eczema.