To the Editor: We want to thank Gu et al1 for their interest in our article2 and comments. We appreciate that Gu et al1 recognized that our data showed some advantages.
Firstly, Gu et al1 raised concerns that 2 of the studies3 , 4 included in the meta-analysis genome-wide association studies (GWAS) of psoriasis we used5 do not mention that they have included doctor-diagnosed psoriasis; however, this is not accurate. Both Strange et al3 and Nair et al4 mentioned in Supplementary Table I, available via Mendeley at https://doi.org/10.17632/hff49h4zpn.1 that all psoriasis cases were doctor diagnosed. Consequently, our study2 included 13,229 doctor-diagnosed psoriasis cases. Secondly, our study2 reports all the sensitivity analyses (Weighted median, magnetic resonance [MR]-Egger, MR-Egger intercept, and MR-PRESSO). We have also included the results of the leave-one-out analysis as Supplementary Material, available via Mendeley at https://doi.org/10.17632/hff49h4zpn.1. Thirdly, the data used in our study come from the largest meta-analysis of GWAS for psoriasis,5 including data from 8 different Caucasian cohorts, so we cannot see any overlapping. Lastly, to our knowledge, there is no available GWAS of psoriasis stratified by severity to be able to examine the association between psoriasis and COVID-19 by mild, moderate, and severe psoriasis cases. We had already mentioned this as a limitation.
To conclude, using the latest available data, our study2 did not support that genetic predisposition to psoriasis is associated with higher susceptibility to being infected, hospitalized, or developing severe COVID-19.
Conflicts of interest
None disclosed.
Footnotes
Funding sources: None.
IRB approval status: Not applicable.
References
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