Background: Among many coronavirus disease 2019 (COVID-19)
integumentary system involvements, alopecia is one of the least
investigated. This disorder has been reported in many individuals
who have suffered from varying severities of COVID-19. We
aimed to systematically review studies evaluating the onset of
different types of alopecia following COVID-19.
Methods: The PubMed, Scopus, Web of Science, and Embase
databases were searched with a specified string of relevant
keywords. After quality assessments, the data of eligible studies
were qualitatively and quantitatively synthesized.
Results: Sixteen studies were included in our review, six of
which underwent meta-analysis for the differences in the risk of
alopecia between males and females. Though the disorder was
not differentiated in all the cases, we found that COVID-19 was
associated with several different types of alopecia, including
telogen effluvium, alopecia areata, alopecia parvimaculata, and
lichen planopilaris. Moreover, although statistically insignificant,
the odds of developing alopecia favored the female population.
Conclusion: Although many hypotheses have been suggested as
to why an individual might be more predisposed to developing
alopecia following COVID-19, the data obtained from the studies
yielded results that could not lead to definite conclusions. Therefore,
we recommend that further studies be conducted to evaluate
the association between the two phenomena more confidently.