COVID 19 Infection Increases the Risk of Alopecia Areata and Alopecia Totalis; Vaccination Reduces the Risk

COVID19 Infection Increases the Risk for Alopecia Areata and other Autoimmune Diseases

A number of studies to date have suggest that patients infected with COVID 19 are at risk for several autoimmune diseases.

A new study set out to investigate the incidence and risks of various autoimmune and autoinflammatory diseases after COVID 19.

To do so, the authors performed a retrospective study using patient data from a nationwide database in Korea. Patients included in the study were those with a PCR positive COVID 19 diagnosis between Oct 8 2020 and Dec 31, 2021 and their data was compared to controls without COVID 19.

In total, there were 354, 527 individuals with COVID 19 that were included in the study, with a mean age 52.24 years. Data was compared to 6, 134, 940 control patients that did not have COVID 19.

Both alopecia areata as well as alopecia totalis were increased by COVID 19. The risks of alopecia areata increased 12 % (adjusted hazard ratio [aHR], 1.12; 95% CI, 1.05-1.19), and the risk of alopecia totalis increased 74 % alopecia totalis (aHR, 1.74; 95% CI, 1.39-2.17).

Many Autoimmune Diseases Increased by COVID Infection

Other diseases also were found to be increased in those with COVID19 including Antineutrophil cytoplasmic antibody– associated vasculitis (aHR, 2.76; 95% CI, 1.64-4.65), Crohn disease (aHR, 1.68; 95% CI, 1.31-2.15), and sarcoidosis (aHR, 1.59; 95% CI, 1.00-2.52). However, the risk of SLE was lower (aHR, 0.47; 95% CI, 0.36-0.61) in the COVID-19

Alopecia Areata and Totalis According to Gender

When Data was analyzed according to gender, the authors showed that both males and females with COVID 19 had an increased risk of developing alopecia totalis. In terms of alopecia areata, males had a decreased risk of alopecia areata and females had an increased risk

Alopecia Areata and Totalis According to Age

When Data was analyzed according to age, the authors showed that younger patients (under 40) with COVID 19 had a decreased risk of risk of developing alopecia totalis and no difference in the risk of alopecia areata.

 Patients over the age of 40 had an increased risk of both alopecia areata and totalis.

Alopecia Areata and Totalis According to Severity

When Data was analyzed according to severity, the authors showed that patients who were in the ICU had a much higher chance of developing alopecia totalis than those not in the ICU (2.45 vs 1.46).

Alopecia Areata and Totalis According to Vaccination Status

Patients who were vaccinated had a lower risk to develop alopecia areata and those who had more complete vaccinations had an even lower risk. Patients that were not vaccinated had a 33 % higher risk of developing alopecia areata (aHR, 1.33; 1.11-1.59) and an even higher risk to develop alopecia totalis (aHR, 2.26; 1.29-3.97)   

Discussion

This is an interesting study which again points to the increased risk of autoimmune disease in those previously infected with COVID 19.

The risk of alopecia totalis was increased in those with severe COVID 19, those over 40 and in those who were not vaccinated.

It’s hard to know exactly what to make of all this data as the data doesn’t always follow perfectly the same trends.

For example, patients under 40 infected with COVID 19 seem to have a decreased risk of alopecia totalis but those over 40 seem to have an increased risk. Males with COVID 19 have a decreased risk for Alopecia areata but females with COVID have an increased risk. (Both have an increased risk for totalis). But nevertheless the main point does seem clear – and that is that patients with COVID 19 overall seem to have an increased risk of alopecia areata and alopecia totalis.

Why are autoimmune diseases increased by COVID19 Infection?

The reasons for this increased autoimmunity area really not entirely clear. Some have hypothesized that patients infected with COVID 19 develop a variety of antibodies to SARS-COV-2 epitopes and these antibodies may cross react with tissue antigens in the human body.  Other studies have proposed that the body’s increase in cytokines (ie. the ‘cytokine storm) to try to stop the SARS-COV-2 infections (like IL1 and IL6) may trigger autoimmune reactions

What about COVID VACCINE Induced Alopecia Areata?

This study suggested that patients who are vaccinated have a lower risk of alopecia areata and patients who are not vaccinated have a higher risk to develop alopecia areata.

It’s clear that this does not apply to everyone. It’s clear that alopecia areata can rarely be triggered by vaccines as well so there is a population of patients who actually develop AA from the vaccine. A nice systematic review by Pastukhova E et al on this topic can be found in the references below,

REFERENCE

Lim SG et al. Autoimmune and Autoinflammatory Connective Tissue Disorders Following COVID-19  JAMA Netw Open . 2023 Oct 2;6(10):e2336120.

Pastukhova E et al. Alopecia Areata as a Sequela of COVID-19 Vaccination: A Systematic Review J Cutan Med Surg . 2023 Jan-Feb;27(1):64-65.

Genco L et al.  Alopecia Areata after COVID-19 Vaccines. Skin Appendage Disord. 2023 Mar;9(2):141-143.