In a recent review published in Biomedicines, a group of authors explored the relationship between coronavirus disease 2019 (COVID-19) vaccination and psoriasis onset or exacerbation, utilizing data from 49 studies, while emphasizing the importance of vaccination and the need for further research.
Background
Psoriasis, a chronic skin disorder, affects millions globally and is marked by red, scaly patches. Its comorbidities include hypertension, diabetes, and anxiety, impacting mental well-being and quality of life.
Treatment considers skin lesions, comorbidities, and psychosocial aspects, with options including creams, phototherapy, and biologic therapies for varying severity. The introduction of biological drugs has notably improved effectiveness and safety. Treatment is customized based on the severity and impact on the patient’s life.
The COVID-19 pandemic brought teledermatology to the forefront for remote care and COVID-19 vaccines to control the virus. Mild to moderate adverse events occurred post-vaccination, and some reports linked vaccination with psoriasis exacerbation or onset, though conclusive research on this connection remains sparse.
About the study
The present study involved a comprehensive review of literature from databases such as PubMed, Embase, Cochrane Skin, MEDLINE, and Google Scholar until June 1, 2023. The research adhered to the preferred reporting items for systematic reviews as well as meta-analyses (PRISMA) guidelines, utilizing keywords related to COVID-19, vaccines, psoriasis, and specific vaccines.
The types of manuscripts analyzed ranged from reviews to case series. The aim was to include studies with at least one patient who showed new-onset or worsened psoriasis post- COVID-19 vaccination. Only four vaccines were considered, while studies relating to other vaccines or psoriatic arthritis were excluded. All clinical phenotypes of psoriasis were included.
The search was refined through text and abstract reviews of articles, along with a revision of bibliographies to capture possibly overlooked articles. This article didn’t involve any new studies with animal or human participants conducted by the authors.
Study results
The present review included 49 studies involving 134 patients. 27 cases of new-onset psoriasis post-COVID-19 vaccination were reported, with 37% male, 48.1% female, and 14.8% unreported gender. The average age was 54.4 ± 20.9 years. The prevalent phenotype was plaque psoriasis (33.3%), followed by guttate (25.9%), pustular (14.8%), nail (11.1%), and annular psoriasis (3.7%).
The most common vaccine associated with psoriasis onset was mRNABNT162b2 (55.5%), followed by AZD1222 (18.5%) and mRNA-1273 (11.1%). The average time between administration of the vaccine and new-onset psoriasis was 10.3 ± 6.4 days. Most cases were mild and managed with topical treatments (33.3%), systemic drugs (11.1%), biologics (18.5%), apremilast (7.4%), or no treatment (3.7%).
Regarding psoriasis exacerbation, a total of 107 cases were reported, with 57% male and 43% female, averaging 56.5 ± 13.4 years old. The most associated vaccine was mRNABNT162b2 (61.7%), followed by AZD1222 (19.6%) and mRNA-1273 (18.7%).
The average time between vaccination and psoriasis exacerbation was 13.7 ± 14.4 days. Biologic treatment was most commonly used (36.4%), with first-time biologic treatments making up 30.8% of cases. Moderate-to-severe forms of the disease were reported, leading to the use of systemic drugs and biologics in 44% of patients.
Discussion
The COVID-19 pandemic has brought changes to daily clinical practice, including vaccination as the primary strategy to contain the virus spread. Though initial safety concerns have been overcome, several cutaneous adverse events were reported, mostly mild and self-limiting.
In the context of psoriasis, the pandemic has led to reported cases of exacerbation or new-onset of the disease following COVID-19 vaccination. A review of 49 studies revealed 134 patients experiencing new-onset psoriasis or exacerbation.
The most common vaccine associated with psoriasis was mRNABNT162b2, and plaque psoriasis was the most frequent clinical phenotype. The cases were successfully treated with various medications, with a difference noted between new-onset and flare-up groups in biologic treatment. 19 (17.8%) patients under biologic treatment for psoriasis experienced exacerbation at the moment of the flare-up.
However, the literature lacks direct evidence linking COVID-19 vaccination to psoriasis development. The mechanisms of vaccine-induced immune responses differ from those implicated in psoriasis. The vaccination might theoretically contribute to exacerbation in those already diagnosed but proving a causal relationship is complex.
Cases of de novo psoriasis or exacerbation have been reported with both messenger ribonucleic acid (mRNA) and viral vector-based vaccines, suggesting a possible connection to the vaccination process rather than the mechanism of the vaccines.
It is crucial to differentiate between coincidence and causation. Psoriasis, being a common condition, might emerge coincidentally after vaccination without direct causality.
Thorough epidemiological studies are required to establish any link between COVID-19 vaccination and psoriasis development. Importantly, as it stands with current knowledge, the benefits of COVID-19 vaccination in preventing and controlling the virus far outweigh the potential risks, underlining the overall positive benefit-risk profile of vaccination.
Conclusions
Despite reported cases of new or worsening psoriasis following COVID-19 vaccination, the campaign was successful with all cases effectively managed. Many studies in this review showed that the majority of new cases were treated topically, and systemic treatments primarily addressed flare-ups.
Globally, plaque psoriasis was most common in both new and exacerbated cases, with severe cases more prevalent in those with a history of the disease, likely due to self-medication of milder forms.
However, understanding potential pathogenic mechanisms to identify "at-risk" patients requires further study. The overall benefit-risk profile of COVID-19 vaccination affirms that vaccination should continue.