Ann Dermatol.  2025 Aug;37(4):250-258. 10.5021/ad.25.007.

New Onset of Hair Loss Disorders During the Coronavirus Disease 2019 Pandemic: A Korean Nationwide Population-Based Study

• Cho Y
• Lim JW
• Yoon YN
• Kim CY
• Lee YW
• Choe YB
• Yu   DA

• KMID: 2570442
• DOI: http://doi.org/10.5021/ad.25.007

Abstract

Background
An increased incidence of hair loss disorders has been noted among patients with coronavirus disease 2019 (COVID-19) and individuals vaccinated against COVID-19. However, research involving large populations on this topic is lacking.
Objective
To investigate the risks associated with developing hair loss disorders in patients with COVID-19 and individuals vaccinated against COVID-19.
Methods
This nationwide, population-based, cross-sectional study included patients diagnosed with COVID-19 and healthy individuals without a history of COVID-19 infection registered in the Korean National Health Insurance Service (NHIS) database between January 1, 2021, and December 31, 2021. COVID-19 infection and vaccine databases were integrated using this NHIS database. The odds ratios of hair loss disorders were compared using multivariate logistic regression models.
Results
COVID-19 infection was associated with an increased risk of total alopecia (adjusted odds ratio [aOR], 1.076; 95% confidence interval [CI], 1.002–1.156), although this association was not significant after propensity score matching. No significant associations were found between COVID-19 infection and alopecia areata or telogen effluvium. However, COVID-19 vaccination was positively correlated with total alopecia (aOR, 1.266; 95% CI, 1.191–1.346), alopecia areata (aOR, 1.243; 95% CI, 1.154–1.339), and telogen effluvium (aOR, 1.495; 95% CI, 1.133–1.974).
Conclusion
COVID-19 vaccination was positively correlated with hair loss disorders but not COVID-19 infection. However, given the advantages of vaccines in reducing COVID-19 mortality and morbidity, alopecia may be relatively reversible and less severe. Physicians need to understand the benefits and possible side effects of the COVID-19 vaccine.

Keyword

Alopecia; Alopecia areata; COVID-19; COVID-19 vaccine