BACKGROUND

Trichoscopy is the main non-invasive method of diagnosing androgenetic alopecia (AGA). Trichoscopic criteria for AGA have been formulated, but there are no unequivocal data on the occurrence of major trichoscopic features, including at different stages of hair loss.

OBJECTIVE

To assess the incidence of major trichoscopic markers in patients with AGA depending on gender and stage of hair loss.

MATERIAL AND METHODS

Ninety-two practically healthy patients with AGA were examined. All patients underwent trichoscopy at 20x and 60x magnification in the frontoparietal area. The main trichoscopic markers of AGA were studied: anisotrichosis, increased single follicular units and vellus hairs, “yellow dots”, and perifollicular hyperpigmentation. All patients were divided into two groups according to the AGA stage to determine the rate of the AGA signs: group 1 included patients with early stages of alopecia and group 2 with advanced stages of alopecia.

RESULTS

In patients with AGA, the most common trichoscopic features are anisotrichosis, “yellow dots”, and an increased proportion of vellus hairs; the signs were detected in 86%, 85%, and 83% of cases, respectively. The frequency of these signs is not reliably related to the gender of the patient. In advanced stages of AGA compared to early stages, a decrease in the incidence of vellus hairs was found in 64% and 91% of patients, respectively (p<0.05), and an increase in the incidence of single follicular units in 86% and 45% of patients, respectively (p<0.05).

CONCLUSION

The main trichoscopic markers in the early stages of AGA are anisotrichosis, an increased proportion of vellus hairs, and the “yellow dots”; the presence of 2 of the 3 signs provides an early diagnosis of AGA with a sensitivity of 73%. The main trichoscopic markers at advanced stages of AGA are anisotrichosis, the “yellow dots”, and an increase in solitary follicular units; the presence of 2 of 3 signs provides a diagnosis of AGA with a sensitivity of 78%.