Trichoscopic Markers as Predictors of Treatment Response in Androgenetic Alopecia: A Systematic Review

BACKGROUNDAndrogenetic alopecia (AGA) is the most common form of hair loss in adults characterized by follicular miniaturization and hair thinning. Common treatments include topical minoxidil and oral finasteride. Accurate, noninvasive diagnostic tools such as trichoscopy are essential for guiding therapy and predicting treatment response.

AIMSTo evaluate key trichoscopic markers—including Hair Shaft Diameter Variability (HSDV), Terminal-to-Vellus Hair Ratio (T/V ratio), and vellus hair percentage—and their correlation with disease severity and therapeutic outcomes in AGA.

METHODSA systematic review was conducted on studies published from 2021 to 2026 that quantitatively assessed trichoscopic markers for predicting treatment response in AGA. Due to heterogeneity in study methodologies, a qualitative synthesis was performed.

RESULTSElevated HSDV reflects the coexistence of terminal and miniaturized hairs, with reductions after treatment indicating reversal of miniaturization and serving as an early sensitive marker of efficacy. The T/V ratio increases with effective treatment, mirroring follicular health improvement. Changes in vellus hair percentage provide indications of active disease progression or recovery.

CONCLUSIONTrichoscopic markers offer valuable frameworks for personalized treatment and clinical monitoring. Integration of such markers into routine practice is supported to optimize the management of AGA.

Abstract from Crossref