No Causal Relationship Between Psoriasis and COVID-19 Susceptibility, Severity

A genetic predisposition to psoriasis is not associated with increased susceptibility to COVID-19 infection, according to study findings published in the Journal of the American Academy of Dermatology.

Researchers conducted an updated Mendelian randomization (MR) analysis using summary statistics for psoriasis obtained from the largest genome-wide association meta-analysis of European ancestry. The researchers evaluated associations between a genetic predisposition for psoriasis and COVID-19 infection, including susceptibility, severe disease, and hospitalization risks. The analysis included data captured from 13,229 patients with dermatologist-diagnosed psoriasis and 21,543 control patients. Phenotype data also were obtained from the COVID-19 Host Genetics Initiative. 

The inverse variance–weighted method was used to calculate odds ratios [ORs], and a Bonferroni-corrected significance level of P <.05/3 (P =.017) was considered statistically significant. Sensitivity analyses were also conducted, including weighted median and weighted mode, as well as MR-Egger and MR-pleiotropy residual sum and outlier (PRESSO) testing.

Inverse variance-weighted analysis of patients infected with COVID-19 in the psoriasis and control groups showed no significant association between a genetic predisposition to psoriasis and increased COVID-19 susceptibility (OR, 0.994; 95% CI, 0.98-1.009; P =.465). There also were no significant associations observed between a genetic predisposition to psoriasis and an increased risk for COVID-19-related hospitalization (OR, 1.003; 95% CI, 0.965-1.043; P =.876) or severe disease (OR, 1.009; 95% CI, 0.951-1.07; P =.764), with similar findings noted in sensitivity analyses. For all 3 of these associations, evidence was scarce for horizontal pleiotropy (MR-Egger intercept, P =.499; P =.106; and P =.106, respectively).

After correction for outliers, MR-PRESSO testing demonstrated no association with any COVID-19 phenotype, and no influential single nucleotide polymorphism were noted.

In a bidirectional analysis, a genetic predisposition to COVID-19 infection was not found to increase the risk for psoriasis.

“Our study does not support that genetic predisposition to psoriasis is associated with higher susceptibility to being infected, hospitalized, or developing severe COVID-19,” the researchers concluded.

This article originally appeared on Dermatology Advisor