Despite several recent studies, the prognostic factors of the outcome for Alopecia Areata are not yet fully determined. In order to gain a fuller understanding of prognostic indicators, researchers at Tokyo Medical University conducted a study of 1030 patients with Alopecia Areata.
The study, which was published in Journal of American Academy of Dermatology, examined the participants retrospectively for three years and followed them up for 24 months or more using a questionnaire. The key areas of interest were age at onset, severity of hair loss and treatment modalities. The researchers were also keen to see whether there was a difference in prognosis between rapidly progressive alopecia areata (RPAA) and non- RPAA patients. In total there were 199 patients with RPAA and 831 patients with non-RPAA.
The findings indicated that the most typical age at onset was early 30s for males and in the 20s for females. Regardless of the type of alopecia areata, an early onset was associated with poorer prognosis than a late onset. Similarly, a previous history of alopecia areata was related to a poor prognosis but was not related to the type of alopecia areata. One factor that appeared to be associated with a good prognosis was regeneration of vellus hairs and the authors argued that the extent of hair loss was not related to a poor prognosis. This finding is particularly interesting as it is at odds with previous reports and implies that the hair loss that has previously been associated with poor prognosis may be relevant to alopecia areata patients in general but not RPAA patients. Perhaps the most encouraging finding was that treatment modality was not related to a poor prognosis.
The value of this study comes not only from its sample size, but also from the statistical analysis that they utilised, which is more robust than previous studies. However, the nature of the study is bound to have some problems. For instance, once the large sample has been divided into groups, it becomes clear that the comparison between them is challenging as the follow up period of patients differs from case to case. Similarly, the authors note that some patients changed treatment modality throughout the study, yet these were not excluded.