Relationship of Hair Regrowth Pattern in Alopecia Areata Patches According to DIMT Classification with Treatment Modalities and Patch Size: A Retrospective Cross-Sectional Analysis

BACKGROUND: The morphology of hair regrowth in alopecia areata (AA) patches could be classified into four types, namely diffuse, irregular, marginal, and targetoid patterns, according to the DIMT classification. However, factors affecting hair regrowth patterns have not been investigated. OBJECTIVE: We investigated whether the DIMT-classified hair regrowth patterns of AA patches are associated with treatment modality and patch size. METHODS: We conducted a retrospective, cross-sectional study of 152 AA patches with hair regrowth. RESULTS: The associations between the diffuse pattern and patch size >2 cm (p=0.006; odds ratio [OR]: 0.36, 95% confidence interval [CI]: 0.17~0.74), between the irregular pattern and triamcinolone acetonide intralesional injection (p<0.001; OR: 274.87, 95% CI: 25.75~2,933.56), between the marginal pattern and systemic and topical corticosteroid (p=0.018; OR: 4.89, 95% CI: 1.31~18.27), and between the targetoid pattern and patch size >2 cm (p=0.028; OR: 2.50, 95% CI: 1.10~5.68) were statistically significant. CONCLUSION: Treatment modalities and patch size are the factors affecting hair regrowth patterns in AA patches.