Trichoscopic findings of androgenetic alopecia and their association with disease severity

Trichoscopy is a novel tool for the diagnosis of hair loss disorders such as androgenetic alopecia ( AGA ), but there are still few reports on the association between trichoscopic findings and disease severity, especially in the Chinese population. A case–control observational study was conducted to observe the trichoscopic findings of AGA and to evaluate their relationship with disease severity. Trichoscopic examination was performed with a handheld dermoscope on 750 Chinese male AGA ( MAGA ) and 200 female AGA ( FAGA ) patients, along with 100 male and 50 female normal controls. Trichoscopically, AGA was featured by hair shaft thickness heterogeneity ( HSTH ), brown peripilar sign ( BPPS ), white peripilar sign ( WPPS ), yellow dots, pinpoint white dots, focal atrichia and scalp pigmentation. No significant difference in the occipital area was found between AGA and controls ( P  > 0.05). HSTH of more than 20% was demonstrated in all MAGA patients, and HSTH of more than 10% was seen in all FAGA patients. WPPS , yellow dots, pinpoint white dots, focal atrichia and scalp pigmentation were positively related to severity of disease ( P  < 0.05), while BPPS was the contrary ( P  < 0.05). HSTH is an essential criterion for diagnosing AGA . BPPS was more common in early AGA . However, WPPS , yellow dots, pinpoint white dots, focal atrichia and scalp pigmentation are positively correlated with advanced AGA .