Clinical Characteristics and Factors Associated with Hair Loss Severity in Chronic Hepatitis B Patients Receiving Pegylated Interferon-Alpha: A Retrospective Cohort Study.

OBJECTIVE: To characterize the phenotype and evaluate factors associated with hair loss severity in patients already experiencing alopecia during pegylated interferon alpha therapy or nucleos(t)ide analog therapy for CHB. METHODS: This retrospective cohort study included 78 CHB patients presenting with hair loss. Thirty-eight patients received Peg-IFNα combined with nucleos(t)ide analogs, and 40 received nucleos(t)ide analogs alone. Clinical and trichoscopic characteristics were assessed, and hair loss severity was categorized by daily hair shedding (<50, 50-100, >100 hairs/day). Multivariate ordered logistic regression examined the independent association between interferon therapy and hair loss severity, adjusting for age, sex, duration of alopecia, family history, and other contributing factors. RESULTS: Telogen effluvium was significantly more frequent in the interferon group than in the nucleos(t)ide analog group (73.7% vs 25.0%, P<0.001), accompanied by shorter disease duration (median 2.0 vs 24.0 months, P<0.001), and more severe daily shedding (>100 hairs/day: 26.3% vs 10.0%, P=0.014). Interferon therapy independently increased hair loss severity (OR=3.21, 95% CI: 1.00-10.28, P=0.049). Increasing age (OR=0.89, P=0.005) and male sex (OR=0.29, P=0.018) were protective. CONCLUSION: Among CHB patients presenting with alopecia, Peg-IFNα therapy is independently associated with greater hair loss severity, predominantly presenting as acute telogen effluvium. This underscores the need for proactive counseling and monitoring, particularly among younger female patients.