New Study Adds Support to Notion that COVID19 Can Trigger Alopecia Areata

COVID-19 infection can trigger several autoimmune diseases, including rheumatoid arthritis, lupus, and many more. (For further review, see the article “Autoimmune Disease Risk Increased After COVID19 Infection”.) There is growing evidence that COVID-19 infection can trigger AA or flare AA in those who already have the disease.

• A 2023 study by Lim et al. showed an increase in both alopecia areata and alopecia totalis following COVID infection and a reduced risk in those who were vaccinated

• A 2023 study by Tesch  et al. et al. showed an increase in both alopecia areata following COVID infection

Kim et al. 2024

A new study supports the notion that COVID-19 infection increases the risk of all forms of alopecia areata in adults.

The authors conducted a cohort study to investigate the association between COVID-19 and AA. They studied patients between October 8, 2020, and September 30, 2021.

The study comprised 259 369 patients with COVID-19 and 259 369 uninfected controls.

Results

To begin with, the authors found an increased risk of telogen effluvium in the cohort with COVID-19 compared with the uninfected cohort (AHR, 6.40; 95% CI, 4.92- 8.33).

Incidence of AA Increased in COVID-19.

The incidence of alopecia areata in patients with COVID-19 was found to be almost two times higher than in patients who did not have COVID infection (i.e. 43.19 per 10 000 person-years [PY] vs 23.61 per 10 000 PY)

Incidence of both Patchy AA and AT/AU Increased in COVID-19.

The authors studied the incidence of mild and severe alopecia areata separately. They showed that the incidence of all forms of alopecia areata increased with COVID-19 infection.

For patchy AA. The incidence of patchy AA was 35.94 per 10,000 PY in patients with COVID-19 and 19.43 per 10,000 PY in controls.

For AT/AU. The incidence of alopecia totalis and unversalis was 7.24 per 10,000 PY in patients with COVID-19 and 4.18 per 10,000 PY in controls.

Adult Patients and Females at Higher Risk

The incidence of AA after COVID-19 was significantly increased in all groups older than 20 years. In this study, the risk of AA was not increased in children and adolescents following COVID-19. There was a higher risk among both females and males, with a higher risk in females than males.

The Prevalence of Alopecia is Increasing in post-pandemic Korea

The authors noted that the incidence and prevalence of AA and AT/AU remained constant from 2006 to 2015. They point out that the prevalence has now increased following the COVID-19 pandemic.

REFERENCES**

Kim J-S et al. Risk of Alopecia Areata After COVID-19. JAMA Dermatol. 2024 Feb 1;160(2):232-235. doi: 10.1001/jamadermatol.2023.5559.

Christensen RE, Jafferany M. Association between alopecia areata and COVID-19: a systematic review.JAAD Int. 2022;7:57-61. doi:10.1016/j.jdin.2022. 02.002 3.

Birkett L, Singh P, Mosahebi A, Dhar S. Possible associations between alopecia areata and COVID-19 vaccination and infection. Aesthet Surg J. 2022; 42(11):NP699-NP702. doi:10.1093/asj/sjac165

Kutlu Ö, Aktaş H, İmren IG, Metin A. Short-term stress-related increasing cases of alopecia areata during the COVID-19 pandemic. J Dermatolog Treat. 2022;33(2):1177. doi:10.1080/09546634.2020.1782820

Kim J, Hong K, Gómez Gómez RE, Kim S, Chun BC. Lack of evidence of COVID-19 being a risk factor of alopecia areata: results of a national cohort study in South Korea. Front Med (Lausanne). 2021;8:758069. doi:10.3389/fmed. 2021.758069